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1.

Please select your category:

2.

Calculations

What is the optical power (D) of a convex spherical lens with a focal length of 25 cm?

-2.50D

-4.00D

+4.00D

+2.50D

3.

Calculations

Transpose the -4.00 DS/ -3.00 DC X 45 into positive cylinder notation?

−7.00 DS/ +3.00 DCx45

−5.50 DS/ +3.00 DCx45

−7.00 DS/ +3.00 DCx135

−5.50 DS/ +3.00 DCx135

4.

Calculations

A hypermetrope whose glasses contain +5.00 DS lenses wants to wear contact lenses. What is the dioptric power of the contact lens that he would require? (Back vertex distance = 15 mm)

+ 5.4 dioptres

+ 5.8 dioptres

- 5.0 dioptres

+4.5 dioptres

5.

Calculations

A crown glass prism in air has an apical angle of 4 degrees. What will the approximate angle of deviation be in the position of minimum deviation?

4 degrees

8 degrees

2 degrees

16 degrees

6.

Calculations

A glass prism (refractive index 1.5) of 20 prism diopters deviates an incident of ray of light through?

5 degrees

10 degrees

40 degrees

20 degrees

7.

Calculations

The spherical equivalent of a lens with power +3.00DS/-2.00 DC is?

+2.00 DS

+1.00 DS

-0.50 DS

-1.00 DS

8.

Calculations

Transpose +2.00 DS/ -1.00 DC x 180 to the base curve -2.00 D?

+4.00 DS/ (-3.00 DC x 90/-3.00 DC x 180)

+4.00 DS/ (-2.00 DC x 90/-1.00 DC x 180)

+4.00 DS/ (-2.00 DC x 90/-3.00 DC x 180)

+4.00 DS/ (-2.00 DC x 90/+1.00 DC x 180)

9.

Calculations

What is the magnification of a loupe of power +16 diopters?

x 32

x 4

x 8

x 64

10.

Calculations

An eye has axial length 23.0mm, with average keratometry readings of 42 diopters. Using the SRK formula (constant 118.9), aiming for emmetropia, the calculated power of an intraocular lens implant would be:

24.60 D

24.30 D

23.60 D

23.30 D

11.

Calculations

What is the dioptric lens power of simple magnifying glass (loupe) with a magnification of 2.5x?

25 dioptres

2.5 dioptres

10 dioptres

4 dioptres

12.

Calculations

What is the accommodative power required for a myope with a -1.5 dioptre prescription to read unaided at 25 cm?

2.5 dioptre

1 dioptre

5.5 dioptre

7 dioptre

13.

Calculations

What magnitude of accommodation will be required for a hypermetropic patient within +2 dioptre prescription to read unaided at 20cm?

10 dioptres

3 dioptres

5 dioptres

7 dioptres

14.

Calculations

A patient's prescription is +2.00 DS/ -1.00 DC axis 180. What is the topic transposition of this to the base curve -4.00 D?

+6.00 DS/ (-4.00 DC x 180/-1.00 DC x 90)

+6.00 DS/ (-4.00 DC x 90/-5.00 DC x 180)

+1.00 DS/ (+1.00 DC x 90/-5.00 DC x 180)

+1.00 DS/ (-5.00 DC x 180/+1.00 DC x 90)

15.

Calculations

What is the degree of magnification when viewing the funds of a patient with 10 dioptres of myopia with a direct ophthalmoscope?

x 15

x 17.5

x 2.5

x 12.5

16.

Calculations

What is the lens to object working distance of a simple magnifying glass of 2.5 x magnifications?

2.5 cm

5 cm

10 cm

20 cm

17.

Calculations

Which of the following transpositions is incorrect?

-3.75/ -1.75 x 80 = -5.50/ +1.75 x 170

-1.75/ -1.25 x 60 = -3.00/ +1.25 x 150

+4.50/ -2.25 x 140 = +2.25/ +2.25 x 50

+2.00/ -3.25 x 20 = +1.25/ +3.25 x 110

18.

Calculations

A +4.00D spectacle lens is decentered 5 mm nasally. What type of prism effect is induced?

2Δ Base In

2Δ Base Out

2Δ Base Up

No prism is induced

19.

Calculations

What is the tube length of an astronomical telescope with a +4.00D objective lens and a +10.00D eyepiece lens

35 cm

15 cm

30 cm

20 cm

20.

Calculations

What is the prismatic effect (prism dioptres) of a 4 dioptre lens that has been decanted by 30 mm?

30

0.75

12

120

21.

Calculations

An object is placed 50cm in front of a concave spherical mirror with a radius of curvature of 2.0m. What image is produced?

Real, diminished

Virtual, enlarged

Real, enlarged

Virtual, diminished

22.

Calculations

What is the Brewster angle when light travels from air to glass (n= 1.50)?

47.6

56.3

65.7

41.8

23.

Calculations

How much does a 15Δ prism bend light, in degrees?

15 degrees

8.53 degrees

7.5 degrees

12.4 degrees

24.

Calculations

What is the critical angle for light travelling from glass (n=1.50) to air?

47.6 degrees

41.8 degrees

65.7 degrees

56.7 degrees

25.

Calculations

Convert the following spectacle prescription from plus-cylinder to minus-cylinder notation: +2.00 / +1.50 × 90

+2.00 / -1.50 × 180

+3.50 / -1.50 × 180

+0.50 / -1.50 × 180

+3.50 / -1.50 × 90

26.

Calculations

If a cornea has an anterior radius of curvature of 7.7 mm, a posterior radius of curvature of 6.8 mm, and a centre of thickness of 0.5 mm, what will its dioptric power be if it is submerged in water? Assume index of refraction of water =1.333; index of refraction of cornea = 1.376; index of refraction of aqueous = 1.336

+32.00 D

+37.60 D

-5.89 D

-0.30 D

27.

Calculations

A cyclopegic refraction is performed for on a non verbal, adult patient at a testing distance of 67 cm. The results for the right eye is as follows: +3D share neutralises the reflex when the streak is horizontal (180 degrees); +4D sphere neutralises the reflex when the streak is vertical ( 90 degrees). What is the refraction of the right eye?

+1.50 (sphere) + 1.00 x90

+3.00 (sphere) + 1.00 x90

+1.50 (sphere) - 1.00 x90

+3.00 (sphere) - 1.00 x90

28.

Calculations

During cataract surgery on a patient with an eye of axial length of 23 mm, it becomes necessary to change the IOL type. The A constant for the original IOL is 118.4 and will give a bower of 21.5 dioptres. The A constant for the new IOL is 117.4. What is the power of the new IOL?

21.0 dioptres

22.0 dioptres

22.5 dioptres

20.5 dioptres

29.

Calculations

An object is placed 50cm in front of a concave spherical mirror with a radius of curvature of 2.0m. What is the transverse magnification of the image?

x4

x2

x3

x1

30.

Calculations

At 20 feet, the smallest letters that a child;d can read is the 20/60 line. You have the child walk towards the eye chart. How far does she walk before she can see the 20/20 line?

15 feet

7 feet

5 feet

13 feet

31.

Calculations

What is the maximum amplitude of accommodation of an emmetropic patient with a near point of 20 cm?

5 dioptres

8 dioptres

10 dioptres

2 dioptres

32.

Calculations

Using this instrument with a +13D lens where is the image

8 cm in front of the lens

0.08 cm in front of the lens

0.08 cm behind the lens

8 cm behind the lens

33.

Calculations

An object is placed 50cm in front of a concave spherical mirror with a radius of curvature of 2.0m. What is the power of the mirror?

+1.00

-2.00

-1.00

+2.00

34.

Calculations

If a 10 dioptre concave lens is decentered by 2cm temporally, this will result in a:

20 prism dioptre base-in prism

5 prism dioptre base-out prism

5 prism dioptre base-in prism

20 prism dioptre base-out prism

35.

Calculations

What is the spherical equivalent of -3.50/+1.50 axis 70?

-5.00 DS

-2.75 DS

-2.00/-1.50 axis 110

-2.00 DS

36.

Calculations

During cataract surgery a complication occurs and the decision is made to place the intraocular lens (IOL) in sulcus. A 23.5 diopter IOOL has been planned for placement in the capsular bag. Which of the following lens powers is most appropriate for placement in the sulcus?

22.50 dioptre

21.50 dioptre

24.5 dioptre

25.5 dioptre

37.

Mirrors

Which type of mirror is commonly used in car rearview mirrors?

Parabolic mirror

Concave mirror

Plane mirror

Convex mirror

38.

Mirrors

What optical principle allows a kaleidoscope to form symmetrical patterns?

Chromatic aberration

Total internal reflection

Dispersion

Diffraction

39.

Mirrors

The object lies outside the centre of curvature of a concave mirror. How is the image formed by the mirror best best described?

Real inverted enlarged

Virtual erect diminished

Virtual erect enlarged

Real inverted diminished

40.

Mirrors

How does a two-way mirror work?

It acts as a polarizer, allowing only certain wavelengths through.

It transmits light in one direction while reflecting most light from the other.

It refracts light instead of reflecting it.

It reflects all light from both sides equally.

41.

Mirrors

An object is placed between the center of curvature (C) and the focal point (F) of a concave mirror. What will be the characteristics of the image formed?

Real, inverted, and enlarged

Real, inverted, and diminished

No image is formed

Virtual, erect, and enlarged

42.

Mirrors

When an object is placed at the focal point (F) of a concave mirror, what is the most likely outcome?

A virtual, erect, and diminished image is formed.

A real, erect, and same-sized image is formed

A real, inverted, and magnified image is formed.

No image is formed because the reflected rays are parallel.

43.

Mirrors

Which of the following statements is true about the image formed by a concave mirror when the object is placed between the focal point (F) and the mirror?

The image is real, inverted, and diminished

The image is real, erect, and the same size as the object.

The image is virtual, erect, and magnified

No image is formed because light rays do not reflect.

44.

Mirrors

An object is placed beyond the center of curvature (C) of a concave mirror. What will be the characteristics of the image formed?

Real, inverted, and diminished

Real, erect, and enlarged

No image is formed

Virtual, erect, and magnified

45.

Mirrors

The image formed by a convex mirror is least likely to be?

Lateral Inverted

Diminished

Virtual

Erect

46.

Mirrors

Which of the following is least likely to describe the image formed when an object is placed between the focal point (F) and the mirror in a concave mirror?

Virtual

Inverted

Enlarged

Erect

47.

Mirrors

Which of the following is most likely a correct rule when constructing ray diagrams for a concave mirror?

A ray passing through the focal point (F) reflects parallel to the principal axis.

A ray traveling parallel to the principal axis reflects through the focal point (F).

All of the above.

A ray passing through the center of curvature (C) reflects back along the same path.

48.

Mirrors

An object located between the centre of curvature and the principle focus of a concave mirror is most likely?

Virtual

Real

Diminished

Erect

49.

Mirrors

Which of the following is least likely to describe the image formed when an object is placed beyond the center of curvature (C) in a concave mirror?

Inverted

Magnified

Real

Diminished

50.

Aberrations

Which optical aberration is most affected when a lens is tilted?

Spherical aberration

Chromatic aberration

Pincushion distortion

Coma

51.

Aberrations

Which statement about mydriasis is least likely?

There is an increased depth of field

There is an increase in the Stiles-Crawford effect

There is an increase in spherical aberration

There is decreased diffraction of light

52.

Aberrations

Which lens material has the lowest chromatic aberration?

Trivex

High-index plastic

Polycarbonate

Crown Glass

53.

Aberrations

Which type of optical aberration is characterized by different focal points for different wavelengths of light?

Chromatic aberration

Spherical aberration

Coma

Astigmatism

54.

Aberrations

Which of the following statements about dispersion and chromatic aberration is most likely?

Blue-blocking and red-blocking sunglasses improve sharpness by eliminating part of the chromatic interval, thereby reducing chromatic abberation

Red print appears nearer than blue print when both are displayed against a black background

In the human eye, blue rays focus behind red rays

Image sharpness is improved by chromatic aberration in the eyes of the patients with achromatopsia

55.

Aberrations

Coma aberration is most commonly seen in which type of optical system?

Cylindrical lenses

Off-axis point sources

On-axis point sources

High-index lenses

56.

Aberrations

Which is least likely to reduce spherical aberration?

Use of a doublet

Aplanatic surfaces

Use of stops

Pantoscopic tilt

57.

Aberrations

Which of the following adaptations of the eye does not reduce spherical aberration at the retina?

Iris position

Variable refractive index within lens

Graduated corneal curvature

Vitreous at the posterior lens surface acting as a doublet lens

58.

Aberrations

Which of the following lens types is most likely to cause chromatic aberration?

Convex lens with high refractive index

Single-element lenses made of low-dispersion glass

Bifocal lenses with spherical curvature

Lenses with a large aperture and a wide field of view

59.

Aberrations

What is the typical effect of spherical aberration in optical lenses?

Color fringing occurs around the edges of the image

Light rays passing through the optical center are deflected outward

Light rays from the center and edges of the lens focus at different points

The lens magnifies objects excessively at the center

60.

Visual Function

Which of the following is least likely a test of stereoacuity

Titmus

TNO

Frisby

Pelli-Robson

61.

Visual Function

Which of the following is true about LogMar?

A logMAR of 0 is equal to a Snellen score of 6/60

The number of letters increases as you move down the chart

The letter spacing is equal to one letter width

A LogMAR of +1 is equal to Snellen score of 6/6

62.

Visual Function

Which of the following charts can be used to assess visual acuity in a child less than 1 years old?

Kay pictures

LogMAR

Sheridan Gardner

Keeler cards

63.

Visual Function

Which of the following is false about LogMAR?

he row spacing is equal to the height of a letter from the row below

Each letter can be assigned a score of 0.01

The letter size increases in 0..1 LogMAR steps

There are five letters on each line

64.

Visual Function

What is the visual acuity of a newborn?

6/24

6/60

6/18-6/6

6/200-6/60

65.

Visual Function

What visual angle is subtentendedu by a letter on the 6/6 line of a snellen chart at 6cm?

1 minute of arc

5 minutes of arc

5 seconds of arc

1 second of arc

66.

Visual Function

Colour vision is tested using?

TNO

Cardiff

N-type

Ishihara

67.

Visual Function

Which of the following is used to tests the visual acuity of an 18-month-old child?

LogMAR

Cardiff cards

Kay pictures

Sheridan-Gardiner

68.

Visual Function

Which of the following is least likely regarding functional vision loss?

Tunnel vision is seen

Optokinetic nystagmus is absent

Normal pupil with no RAPD

Presentation is with decreased visual acuity and is more common in females

69.

Visual Function

Which of the following is least likely a test of stereo acuity?

worth 4-dot

Titmus

Frisby

Cardiff cards

70.

Visual Function

Which of the following tests sensory function?

Bagolini glasses

Prisms

Titmus

TNO

71.

Visual Function

Which of the following tests does not asses colour vision?

Farnsworth-Munsell

Ishihara

Pelli-Robson

Hardy-Rand-Rittler

72.

Visual Function

A snellen visual acuity of 20/20 is equivalent to which of the following logMAR values?

0.00

1.00

0.02

10.00

73.

Prisms

Which of the the following is least likely regarding the visual image formed by a prism?

Diminished

Virtual

Displaced towards the apex

Erect

74.

Prisms

A prism deviates light by 5 cm at a distance of 1 meter. What is its prismatic power?

10 prism diopters

50 prism diopters

5 prism diopters

0.5 prism diopters

75.

Prisms

Which of the following is least likely to use prisms in spectacle correction?

Treatment of 6th nerve palsy

Treatment of presbyopia

Correction of vertical diplopia

Correction of horizontal diplopia

76.

Prisms

In vision therapy, prisms are most commonly used to treat which of the following conditions?

Hyperopia

Astigmatism

Strabismus

77.

Prisms

Which is most likely about the image formed by a prism?

It is real and displaced towards the apex

It is real and displaced towards the base

It is virtual and displaced toward the apex

It is virtual and displaced towards the base

78.

Prisms

Which of the following least likely determines the angle of deviation of a ray of light when refracted by a prism?

Refracting angle of the prism

Angle of incidence of the ray

Refractive index of the material of which the prism is made

Wavelength of light of the incident ray

79.

Prisms

One prism diopter corresponds to a deviation of how many centimeters at a distance of one meter?

2 cm

0.5 cm

1 cm

5 cm

80.

Prisms

In the treatment of binocular vision disorders, what effect does using prisms in spectacles typically have on the image?

It causes the image to appear doubled

It shifts the image to aid fusion

It reduces the field of vision

It enlarges the image significantly

81.

Prisms

Which of the following prisms causes 180 degrees deviation with no left-to-right transposition?

Fresnel prism

Dove prism

Wollaston prism

Porro prism

82.

Prisms

Which prism causes inversion of the image without deviation or lateral transposition?

Porro prism

Fresnel prism

Dove prism

Wollaston prism

83.

Prisms

Which of the following statements regarding the Prentice position is least likely?

Glass prisms are traditionally held in the prentice position

The angle of incidence equals the angle of emergence

The deviation of light is greater in the Prentice position than in the position of minimum deviation

The incident ray is normal to one surface of the prism

84.

Refraction by the Eye

What is the average dioptric power of an aphakic eye?

22

19

43

58

85.

Refraction by the Eye

When does the eye reach its maximum axial length?

3-7 years old

Does not stop growing

13-18 years old

1-3 years old

86.

Refraction by the Eye

Which most likely describes the far point of the non-accommodated -4.00D myopic eye?

The far point is 20cm anterior to the eye

The far point is 25cm posterior to the eye

The far point is nearer to the eye than is the point of focus of the fully accommodated eye.

The far point and fovea are conjugate points, ,

87.

Refraction by the Eye

What is the size of the adult eye?

24 mm

17 mm

34 mm

28 mm

88.

Refraction by the Eye

What is the refractive index of the cornea?

1.33

1.37

1.40

1.52

89.

Refraction by the Eye

What is the radius of curvature (in mm) of the anterior surface of the cornea?

6.8 mm

7.0 mm

5.7 mm

7.7 mm

90.

Refraction by the Eye

What is the total approximate refractive power of the human eye?

20D

43D

30D

60D

91.

Refraction by the Eye

What is the primary cause of myopia?

Corneal irregularity

Excessive axial length

Weak accommodation

Reduced corneal curvature

92.

Refraction by the Eye

What is the average axial length of an emmetropic human eye?

22 mm

20 mm

24 mm

26 mm

93.

Refraction by the Eye

Which of the following best describes emmetropia?

Light focuses behind the retina without accommodation

Light is scattered throughout the eye without a focal point

Light focuses exactly on the retina without accommodation

Light focuses in front of the retina without accommodation

94.

Refraction by the Eye

What happens to the eyes during the accommodative reflex?

Convergence, miosis, and increased lens curvature

Convergence, mydriasis, and lens flattening

Divergence, miosis, and lens flattening

Divergence, mydriasis, and increased lens curvature

95.

Refraction by the Eye

Approximately how much of the eye's total refractive power comes from the cornea?

43D

25%

60D

10%

96.

Refraction by the Eye

Which of the following is NOT part of the near triad response?

Convergence

Mydriasis

Accommodation

Miosis

97.

Refraction by the Eye

A patient with an axial length of 26.5 mm is likely to have:

Hyperopia

Myopia

Presbyopia

Emmetropia

98.

Refraction by the Eye

Which statement about the optical power of an infant’s eye is true?

It is hyperopic due to a short axial length

It always has a myopic refractive error

It has a lower refractive power than an adult’s eye

It has fully developed accommodation at birth

99.

Refraction by the Eye

Which lens type is best suited for patients with high myopia (-10.00D and above)?

Bifocal lenses

Plus lenses

Aspheric high-index lenses

Standard plastic lenses

100.

Refraction by the Eye

Which of the following is true about hyperopia (farsightedness)?

It requires concave lenses for correction

The patient may accommodate to compensate for mild hyperopia

It is associated with excessive axial length

Light focuses in front of the retina

101.

Refraction by the Eye

Which of the following best describes the process of emmetropization?

The process of correcting refractive errors using spectacles or contact lenses

The eye's ability to focus light using accommodation

The gradual loss of accommodation with age

The active adjustment of the eye’s axial length and refractive components during development

102.

Refraction by the Eye

Why does the cornea provide more refractive power than the lens?

It is closer to the retina.

It has a higher refractive index.

It is thicker than the lens.

It has a greater curvature.

103.

Refraction by the Eye

Which previous model is Gullstrand's reduced eye a refinement of?

Kepler

Helmholtz

Schooner

Krunenberg

104.

Refraction by the Eye

Based on Gullstrand's reduced eye, which of the following points is 7.08mm behind the anterior corneal surface?

Nodal point

First focal point

Principle point

Second focal point

105.

Refraction by the Eye

In Gullstrand's reduced eye the, how far is the anterior focal point from the anterior cornea?

17.7 cm

15.7 cm

17.7 mm

15.7 mm

106.

Refraction by the Eye

The total refractive power of Gullstrand's reduced eye when relaxed is?

+55.64 diopter

+58.64 diopter

+50.64 diopter

+60.64 diopter

107.

Refraction by the Eye

Which of the following is not proven to slow myopic progression?

Outdoor activity

None of the above

Using reading glasses

Using atropine

108.

Refraction by the Eye

The most likely effective power of the crystalline lens in situ is?

23 diopters

37 diopters

43 diopters

15 diopter

109.

Refraction by the Eye

In a hypermetropic eye, moving a convex lens away from the eye?

The effectivity of the lens is decreased

The effectivity of the lens is increased

None of the above

The effectivity of the lens is unchanged

110.

Refraction by the Eye

Which is is least likely to be true?

The dioptric power of the accommodated eye is called its static refraction

The near point at which an object can be clearly seen when maximum accommodation is used

The range of accommodation is the distance between the far point and near point

The amplitude of accommodation is the dioptric power difference between the eye at rest and when full accommodated

111.

Refraction by the Eye

Which ocular structure has the highest refractive power?

Vitreous humour

Lens

Aqueous humour

Cornea

112.

Refraction by the Eye

Which of the following is true about the lens?

The posterior capsule thins with age

The lens becomes more spherical when looking at the distance

The posterior suture has an inverted Y shape

The anterior suture gas inverted Y shape

113.

Refraction by the Eye

A high AC/A ratio is most likely associated with?

Convergence excess esotropia

Divergence excess esotropia

Convergence weakness

Convergence excess exotropia

114.

Instruments

Which optical instrument provides an upright and non-reversed image of the retina?

Goldman contact lens + slit lamp

Direct ophthalmoscope

Indirect ophthalmoscope + 20D lens

Hruby lens

115.

Instruments

Which one of the following statements about the Geneva lens measure is true?

It is calibrated for the refractive index of crown glass

When placed on a convex surface the central pin is extended relative to the peripheral pins

It uses three spring-loaded pins to measure the surface curvature of a lens

It is possible to deduce the total power of a thin lens by measuring both surface powers and calculating the difference between them

116.

Instruments

Which optical instrument provides an inverted and reversed image of the retina?

Direct ophthalmoscope

Goldman contact lens + slit lamp

Indirect ophthalmoscope + 20D lens

Hruby lens

117.

Instruments

Looking through the inferior mirror of a Zeiss 4 mirror goniolensm you see a foreign body at 7 o'clock. Where is this foreign body in your patient?

11 O'Clock

5 O'Clock

7 O'Clock

1 O'Clock

118.

Instruments

What factor would reduce your field of view when examining a patient with this instrument:

A

Moving closer to the patient

Large pupil size

Hyperopic patient

Myopic patient

119.

Instruments

Which of the following instruments relies on total internal reflection?

Operating microscope

Gonioscopy lens

Direct ophthalmoscope

Fibre-optic intracular illumination system

120.

Instruments

Which Volk examination lenses has an image magnification factor of 0.93?

66 dioptre

90 dioptre

78 dioptre

60 dioptre

121.

Instruments

Using the following instrument, your image would be:

Inverted

Real

9 DD (Disc Diameters)

x20 magnified

122.

Instruments

You examine a patient with the following instrument. Which factor affects your image size:

Distance from patient

Patient's refractive state

Size of pupil

Illumination

123.

Instruments

Which type of patient cannot be examined using the following instrument:

Hyperopic

Myopic

Aphakic

Astigmatic

124.

Instruments

Using this instrument how can you enhance your view of the posterior pole in a myopic patient?

Ask them to keep their glasses on

Use a narrow beam

Use a green filter

Stand further away from the patient

125.

Instruments

Using this instrument how could you enhance your view of a micro-aneurysm?

Remove a myopic patients glasses

Use a narrow beam

Use a red filter

Move away from the patient

126.

Instruments

The image formed by this instrument is not:

Real

Between the patient and the condensing lens

Magnified

Inverted

127.

Instruments

What is the field of view achieved with this instrument?

25 degrees

60 degrees

10 degrees

50 degrees

128.

Instruments

Your field of illumination is restricted by what when using this instrument?

A small pupil

Using a condensing

Hyperopic observer

Hyperopic patient

129.

Instruments

Which of the following is true regarding indirect ophthalmoscopy?

The image is erect

The image is virtual

A +20D concave lens is required

The field of illumination is largest in myopia

130.

Instruments

Your field of view is restricted by what when using this instrument?

Small patient's pupil size

Small observer's pupil size

Large observer's pupil size

large patient's pupil size

131.

Instruments

You move the condensing lens away from a patient whilst using this instrument. You notice that this causes the image size to increases. This means the patient is:

Moving their head

Emmetropic

Hyperopic

Myopic

132.

Instruments

You move the condensing lens away from a patient whilst using this instrument. You notice that the image size gets smaller. This means the patient is:

Myopic

Emmetropic

Hyperopic

Poorly dilated

133.

Instruments

Which one of the following statements about the Hruby lens is incorrect?

The retinal image formed lies within the eye of the patient

The retinal image formed is virtual, erect and diminished

It is used with its concave surface towards the observer

It has a power of -58.6 dioptres

134.

Instruments

which of the following indirect ophthalmoscopy lens gives the sides field of view? 15, 20, 28 , 30 d

15 D

30d

28 D

20 D

135.

Instruments

Which of the following phenomenon is used in optical fibre?

Diffraction

Refraction

Scattering

Total Internal Reflection

136.

Imaging

In fluorescein fungus imaging which colour is the excitation filter?

Yellow

Green

Red

Blue

137.

Imaging

Which of the following properties of light is used by the scanning laser polarimeter to measure nerve fibre layer thickness?

Focal spot size

Pulse duration

Polarization

Power level

138.

Imaging

A patient purchases a pair of yellow sunglasses. Which colour will be hardest to see?

Green

Yellow

Red

Blue

139.

Imaging

Which of the following components is part of an optical coherence tomography (OCT) system?

Split prism

Double pinhole

Laser light source

Beam splitter

140.

Imaging

In fluorescein fungus imaging which colour is the barrier filter?

Blue

Green

Yellow

Red

141.

Imaging

What is the optical principle behind fundus autofluorescence imaging in retinal disease diagnosis?

Absorption of infrared light to highlight choroidal structures

Fluorescence emission from lipofuscin in the retinal pigment epithelium

Reflection of blue light from the inner retina

Light scattering from retinal nerve fiber layers

142.

Imaging

Which type of light is used in Optical Coherence Tomography (OCT)?

Ultraviolet

X-rays

Microwave

Infrared

143.

Imaging

Optical Coherence Tomography (OCT) primarily utilizes which principle to obtain high-resolution images of the retina?

Interference

Diffraction

Fluorescence

Refraction

144.

Imaging

Which of the following best describes fluorescence in ophthalmic imaging?

Scattering of light in all directions

Light absorption at one wavelength and emission at a longer wavelength

Complete absorption of light without re-emission

Reflection of light at the same wavelength

145.

Lasers

Which of the following light wavelengths can cause photokeratitis?

X rays

Visible light

Ultraviolet,

Infrared

146.

Lasers

Which of the following is absorbed by haemoglobin and melanin only?

Frequency-doubled ND:YAG

Argon blue-green

Diode laser

PRP

147.

Lasers

Ophthalmic lasers are under which laser safety class?

1-2

3a-3b

3b-4

2

148.

Lasers

which laser causes it principle effect through photo disruption?

Nd-YAG laser

Cyclodiode laser

Argon laser

Eximer laser

149.

Lasers

Which laser causes it principle effect through photoablation?

Argon laser

Nd-YAG laser

Cyclodiode laser

Eximer laser

150.

Lasers

Which of the following characteristics is a property of all ophthalmic lasers?

Stimulated emission

High efficiency

A plasma active medium

Continuous wave operation

151.

Lasers

Which ophthalmic laser primarily causes its principal effect through photocoagulation?

Nd-YAG laser

Argon laser

Eximer laser

Femtosecond laser

152.

Lasers

The ability of light wave from a laser to form interference fringes with another wave from the same beam, separated in time, is a measure of its?

Directionality

Temporal coherence

Spatial coherence

Intensity

153.

Lasers

What is the primary mechanism of the femtosecond laser in cataract surgery?

Photoablation

Photocoagulation

Thermal coagulation

Photodisruption

154.

Lasers

Which laser emits light at a wavelength of 1064 nm?

Diode laser

Argon laser

Excimer laser

Nd:YAG laser

155.

Lasers

Which laser is commonly used for selective laser trabeculoplasty (SLT) in open-angle glaucoma?

Diode laser

Argon laser

Nd:YAG laser

Excimer laser

156.

Lasers

Which laser is primarily used for panretinal photocoagulation (PRP) in diabetic retinopathy?

Femtosecond laser

Argon laser

Excimer laser

Nd:YAG laser

157.

Lasers

During retinal photocoagulation, which mechanism primarily leads to therapeutic tissue effects?

Photochemical reaction

Photothermal reaction

Photodisruption

Photoablation

158.

Lasers

Which optical principle is primarily responsible for the effect of laser photocoagulation in retinal surgery?

Dispersion of light within the vitreous to induce therapeutic heating

Refractive focusing of the laser to create a photomechanical disruption

Absorption of laser energy leading to a photothermal effect

Reflection of laser light causing retinal coagulation

159.

Cataract Surgery

How do accommodating IOLs attempt to restore dynamic near vision?

Split light into multiple focal points for simultaneous viewing

Change curvature dynamically to alter refractive power

Utilize a pinhole effect to improve near vision

Shift anteriorly and posteriorly in response to ciliary muscle contraction

160.

Cataract Surgery

Which of the following statements correctly describes the relationship between IOL power, axial length and corneal power?

The IOL power should increase as the power of the cornea increases and axial length decreases

The IOL power should ncrease as the power of the cornea decreases and axial length increases

The IOL power should increase as the power of the cornea increases and axial length increases

The IOL power should increase as the power of the cornea decreases and axial length decreases

161.

Cataract Surgery

Why is no anterior chamber depth (ACD) measurement used in the SRK equation?

The SRK was designed to eliminate the need for ACD

Regression analysis did not show increased accuracy when ACD was included in the SRK formula

Postoperative ACD is not necessarily the same as preoperative ACD

Modern IOLs are all designed to have the same AC

162.

Cataract Surgery

Which laser is commonly used for posterior capsulotomy after cataract surgery?

Argon laser

Nd:YAG laser

Femtosecond laser

Excimer laser

163.

Cataract Surgery

Which parameter is least likely to be needed to calculate IOL power before cataract surgery?

Central corneal thickness

Amount of LASIK treatment

Postoperative topography measurements

Preoperative refraction

164.

Cataract Surgery

Which value is not required in the SRK formula for intraocular lens calculation?

Axial length

A-constant for the desired IOL

Average keratometry reading

Anterior chamber depth

165.

Cataract Surgery

In a patient with LASIK, which change introduces the most error in the IOL calculations?

Axial length

Corneal curvature measurements

High-order aberrations

Anterior chamber depth

166.

Cataract Surgery

Which optical phenomenon is most commonly affected by the presence of a cataract?

Reduction in axial length, leading to myopic shift

Enhanced night vision due to lens opacification

Improved near vision due to reduced corneal astigmatism

Increased light scatter and decreased contrast sensitivity

167.

Cataract Surgery

What optical property of ultrasound waves is essential for phacoemulsification?

Infrared absorption creates controlled thermal energy to emulsify the lens

High-frequency sound waves induce cavitation and lens fragmentation

Chromatic dispersion separates nuclear layers for better emulsification

Refraction of light waves within the lens nucleus enhances fragmentation

168.

Cataract Surgery

Which optical change is commonly observed after cataract removal?

Hyperopic shift due to loss of the crystalline lens power

Increased astigmatism from irregular corneal wound healing

Reduced intraocular light scatter and improved night vision

Myopic shift due to corneal steepening

169.

Cataract Surgery

How do multifocal IOLs provide both near and distance vision correction?

They dynamically change curvature based on pupil size

They induce higher-order aberrations that compensate for presbyopia

They use diffractive optics to split incoming light into multiple focal points

They selectively absorb short wavelengths to enhance near focus

170.

Cataract Surgery

What optical principle allows monovision cataract surgery to provide both near and distance vision?

Adjusting pupil dynamics to selectively refract light

Utilizing polarized light filters within IOLs to enhance focus

Creating anisometropia by implanting different-powered IOLs in each eye

Increasing corneal curvature in one eye to mimic accommodation

171.

Cataract Surgery

Why do patients with large pupils often struggle with multifocal IOLs?

Enhanced near vision at the expense of distance vision

Reduced contrast sensitivity due to corneal light scatter

Loss of peripheral vision from excessive pupil dilation

Increased exposure to out-of-focus light rays, causing glare and halos

172.

Cataract Surgery

What is the most critical factor when implanting a toric IOL for astigmatism correction?

Precise alignment of the IOL axis to match the patient's astigmatic axis

Selecting an IOL with a lower refractive index to minimize distortion

Increasing corneal hydration to reduce astigmatic impact

Ensuring a higher-powered spherical IOL to compensate for residual cylinder

173.

Cataract Surgery

How does small incision cataract surgery (SICS) impact postoperative corneal astigmatism?

Reduces corneal astigmatism by minimizing incision-induced changes

Shifts the astigmatic axis to a more oblique orientation

Induces myopic shift due to decreased corneal thickness

Increases irregular astigmatism due to unpredictable corneal wound healing

174.

Cataract Surgery

Why are some intraocular lenses designed to filter blue light?

To reduce phototoxic damage to the retina and improve contrast sensitivity

To improve dark adaptation by blocking peripheral scatter

To decrease pupil constriction and increase retinal illumination

To enhance near vision by selectively focusing shorter wavelengths

175.

Cataract Surgery

How do Extended Depth of Focus (EDOF) intraocular lenses achieve a continuous range of vision?

Increased asphericity to induce controlled spherical aberrations

Elimination of multiple focal points to create a single elongated focus

Use of chromatic aberration correction to extend focal points

Pinhole optics to minimize out-of-focus blur

176.

Cataract Surgery

Why might a surgeon implant a secondary (piggyback) IOL in a pseudophakic patient?

To correct significant residual refractive error

To improve depth perception in monovision patients

To compensate for posterior capsule opacification

To reduce spherical aberrations caused by the first IOL

177.

Cataract Surgery

Which optical phenomenon is most likely to affect visual quality in patients with small pupils after multifocal IOL implantation?

Reduced effect of multifocal optics leading to poor near vision

Widening of peripheral field with loss of central clarity

Increased depth of focus but reduced contrast sensitivity

Increased chromatic aberration due to pupil-dependent refraction

178.

Cataract Surgery

Why are negative-power IOLs sometimes required for extremely high myopia in cataract surgery?

Negative lenses compensate for elongated axial length by neutralizing corneal power

The natural crystalline lens has strong positive power, and its removal necessitates a negative correction

Negative lenses enhance retinal image magnification in myopic patients

A posteriorly placed IOL requires negative power for proper light convergence

179.

Cataract Surgery

What optical aberration is most commonly induced when an IOL is significantly decentered postoperatively?

Chromatic aberration

Spherical aberration

Coma

Barrel distortion

180.

Cataract Surgery

How does reverse optic capture influence refractive outcomes in IOL implantation?

Minimizes glare and halos by reducing light scatter at the IOL edge

Increases posterior capsule opacification by trapping lens fibers

Reduces higher-order aberrations by stabilizing the IOL

Pushes the IOL posteriorly to induce a hyperopic shift

181.

Cataract Surgery

What optical principle contributes to positive dysphotopsia in some IOL patients?

Light scattering due to incomplete posterior capsule opacification

Pupil-dependent refraction misalignment

Excessive chromatic dispersion from multifocal optics

Internal reflection of light at the IOL edge

182.

Refractive Surgery

Which of the following is not a complication of refractive eye surgery?

Glare

PCO

Dry eyes

DLK

183.

Refractive Surgery

How long should soft contact lenses be withheld for before undergoing laser eye surgery?

7-14 days

14-21 days

21-28 days

28-35 days

184.

Refractive Surgery

A corneal flap is created, the storm is then ablated, and the flap is replaced. what is this a description of?

YAG laser capsulotomy

PRK

LASEK

LASIK

185.

Refractive Surgery

Which of the following is not an intervention for myopic correction?

Peripheral corneal ablation with LASIK

Central corneal ablation with LASIK

Negative diopter lens

Central corneal ablation with LASEK

186.

Refractive Surgery

Which of the following is a key difference between PRK and LASIK?

PRK removes less corneal tissue than LASIK

PRK does not require a corneal flap

LASIK has a slower visual recovery than PRK

LASIK has a higher risk of corneal haze

187.

Refractive Surgery

Which of the following is a contraindication for LASIK surgery?

Keratoconus

Presbyopia

A) Mild myopia (-2.00D)

History of dry eyes

188.

Refractive Surgery

Why might a phakic IOL (ICL) be preferred over LASIK in some patients?

Phakic IOLs are only used in presbyopia

Phakic IOLs preserve the cornea

LASIK is the only option for high myopia

LASIK is more effective

189.

Refractive Surgery

What is the primary advantage of SMILE (Small Incision Lenticule Extraction) over LASIK?

No need for a femtosecond laser

Better correction of hyperopia

Less risk of dry eye

Faster recovery

190.

Refractive Surgery

Which instrument is the most accurate for measuring anterior chamber depth?

Indirect ophthalmoscope

Direct ophthalmoscope

Slit lamp with Van Herick technique

Pentacam (Scheimpflug imaging)

191.

Refractive Surgery

Why are IOL power calculations more challenging in post-LASIK patients?

The axial length is affected by previous refractive surgery

Corneal power is inaccurately estimated due to altered curvature

The effective lens position is unpredictable due to changes in corneal biomechanics

The residual epithelial thickness alters the refractive index of the cornea

192.

Retinal Surgery

Which optical phenomenon contributes to improved visualization of the retina during surgery under a microscope?

Light scattering due to small pupil size

Reduction of spherical aberration using coaxial illumination

Total internal reflection at the vitreous-retinal interface

Enhancement of retinal contrast via polarized light filtering

193.

Retinal Surgery

Silicone oil in aphakic eye leads to?

No change

Hyperopic shift

Blindess

Myopic shift

194.

Retinal Surgery

Why are wide-angle viewing systems preferred in modern retinal surgery?

They magnify the central retina, allowing for more detailed surgical precision

They increase image brightness by eliminating reflections from the corneal surface

They provide a panoramic view of the peripheral retina without requiring frequent lens adjustments

They reduce chromatic aberration and enhance color contrast in retinal structures

195.

Retinal Surgery

Which optical property makes perfluorocarbon liquids (PFCL) useful in vitreoretinal surgery?

High specific gravity allowing mechanical flattening of the retina

Low refractive index, improving light transmission through the vitreous

Selective absorption of short-wavelength light, reducing phototoxicity

High viscosity, preventing intraoperative turbulence

196.

Retinal Surgery

Which refractive change is commonly observed following pars plana vitrectomy with gas tamponade?

No significant refractive change

Myopic shift

Hyperopic shift

Astigmatic shift

197.

Retinal Surgery

Which optical aberration is most commonly encountered when performing wide-field retinal imaging?

Distortion due to peripheral magnification differences

Spherical aberration from excessive lens curvature

Coma from off-axis light sources

Chromatic aberration from lens dispersion

198.

Retinal Surgery

What optical principle makes endoillumination essential for vitreoretinal surgery?

Total internal reflection of fiber-optic light enhances contrast

Polarization reduces glare and enhances macular detail

Scattering within the vitreous helps illuminate deep retinal layers

High refractive index of fiber optics ensures focused light delivery

199.

Prescriptions

Which bifocal segment design provides the widest near reading area?

Flat-top bifocal

Progressive lens

Executive bifocal

Round-segment bifocal

200.

Prescriptions

Which of the following is an advantage of soft contact lenses over RGP lenses?

Lower risk of corneal infections

More effective in correcting keratoconus

Higher oxygen permeability

Better initial comfort

201.

Prescriptions

An adult has diplopia and a left hypertrophic of 6Δ. which combination of prisms in his glasses will most likely align the two images for him?

3Δ base down (OD), 3Δ base up (OS)

4Δ base down (OD), 2Δ base down (OS)

6Δ base down (OD), nothing (OS)

3Δ base up(OD), 3Δ base down (OS)

202.

Prescriptions

Which test is commonly used to measure the amplitude of accommodation?

Push-up test

Worth 4-dot test

Bagolini striated lenses

Maddox rod test

203.

Prescriptions

What type of image distortion is most common with high-plus (hyperopic) lenses?

Pincushion distortion

Barrel distortion

Chromatic aberration

Coma

204.

Prescriptions

What strength of lens is needed so that a patient with 20/160 visual acuity can read newsprint without accommodation?

+12.50 D

+8.00 D

+10.00 D

+5.00 D

205.

Prescriptions

Which aberration is reduced by using aspheric lenses?

Distortion

Coma

Spherical aberration

Chromatic aberration

206.

Prescriptions

A Maddox rod is place in front of a patient's right eye with its axis vertical. She is asked to look at a white spot and sees a horizontal red line with the light above it. What does that indicate?

Esophoria

Right hyperphoria

Exophoria

Right hypophoria

207.

Prescriptions

You use the duochrome test to refine the refraction of a patient. The patient says the red letter are much clearer than the green. The patient is:

Astigmatic

Overplussed

Anisometropic

Overminused

208.

Prescriptions

Which optical issue do progressive lenses correct that bifocals do not?

Near vision

Distance vision

High astigmatism

Intermediate vision

209.

Prescriptions

What is the primary purpose of the Jackson Cross Cylinder (JCC) test?

To determine near addition power

To refine the axis and power of astigmatism

To assess accommodation ability

To measure spherical refractive error

210.

Prescriptions

What type of patient benefits the most from myodisc lenses?

Presbyopia

High myopia

Astigmatism

High hyperopia

211.

Prescriptions

What is the primary purpose of an anti-reflective coating on eyeglass lenses?

To prevent all light from entering the eye

To create a mirror effect on the lens surface

To reduce glare and ghost images

To increase light reflection for better contrast

212.

Prescriptions

The base curve of a contact lens is primarily chosen based on which measurement?

Central keratometry readings

Pupil size

Anterior chamber depth

Lens diameter

213.

Prescriptions

What is a key advantage of Fresnel prisms in ophthalmic use?

They do not require refraction correction.

They provide higher magnification.

They reduce chromatic aberration.

They are lightweight and flexible.

214.

Prescriptions

Which function of the tear film is most critical for successful contact lens wear?

Creating a smooth optical surface

Maintaining corneal hydration

Removing debris from the eye

Providing nutrients to the cornea

215.

Prescriptions

What is unique about gradient index (GRIN) lenses compared to standard lenses?

They can only be used in microscopes.

They have a uniform refractive index throughout the material.

They have a continuously varying refractive index.

They work only for concave lenses.

216.

Prescriptions

In clinical practice, a Maddox rod is used to assess which of the following?

Visual acuity

Intraocular pressure

Ocular alignment

Color vision

217.

Prescriptions

How does increasing the base curve radius affect a contact lens fit?

It loosens the lens fit.

It has no effect on fit.

It increases the lens power.

It tightens the lens fit.

218.

Prescriptions

What is the primary effect of high-minus spectacle lenses on retinal image size?

It induces a prismatic shift.

It increases magnification.

It reduces image size.

It has no effect on image size.

219.

Prescriptions

Which type of spherical lens is used to correct myopia?

Plano-convex lens

Cylindrical lens

Concave (diverging) lens

Convex (converging) lens

220.

Prescriptions

Which optical phenomenon may cause double vision when a prism is incorrectly placed in spectacles?

Image displacement

Chromatic aberration

Ghosting

Monocular diplopia

221.

Prescriptions

How does a pinhole improve vision in a hyperopic patient?

It increases accommodation.

It magnifies the image.

It increases the corneal curvature.

It increases depth of focus by reducing peripheral blur.

222.

Prescriptions

What is the primary purpose of a retinoscope in clinical practice?

To examine the retina

To assess intraocular pressure

To measure refractive error objectively

To visualize the anterior chamber

223.

Prescriptions

Which type of contact lens is most commonly used to correct aphakia?

Hybrid lens with aspheric optics

High-plus silicone hydrogel soft lens

Rigid gas-permeable (RGP) corneal lens

Scleral lens

224.

Prescriptions

Which of the following is a correct transcription of a 0.50 Jackson's Cross cylinder?

+0.50 DS/ -0.50 DC

+0.25 DS/ -0.25 DC

+0.25 DS/ -0.50 DC

+0.50 DS/ -0.25 DC

225.

Prescriptions

Regarding the Jackson's cross cylinder?

The handle is traditionally in line with the axis of the negative cylinder

The cylinder in the cross cylinder has twice the power of the sphere

It is equivalent to two superimposed cylindrical lenses with axes at 45 degrees to each other

The cross cylinder's handle is held in line with the axis of the trial cylinder

226.

Prescriptions

Which is least likely in spectacle correction for aphakia?

Barrel distortion

Image magnification

Pin fusion distortion

Ring scotoma

227.

Prescriptions

Which of the following regarding contact lenses is used in patients with dry eyes?

Monthly lenses

Rigid lenses

Silicone hydrogel

Soft lenses

228.

Prescriptions

A patient is fitted with a rigid gas permeable contact lens. The average K reading is 7.67mm, and the base curve of the lens in 7.5 mm. What is the shape of the resultant tear lens?

No tear lens will be formed

Concave

Plano

Convex

229.

Prescriptions

In a myopic patient, which of the following is increased with contact lens wear compared to glasses?

Image magnification

Aniseikonia

Image distortion

Optical aberrations

230.

Prescriptions

Which of the following statement is correct regarding the segment choice when prescribing bifocals for a patient with hyperopia?

A round-top segment is preferred because it lessens image jump

The use of a round-top segment reduces the prismatic displacement effect and increases image jump

A flat-top segment is preferred because of its thin upper edge which causes less prismatic effect

The practitioner should leave the choice of the segment type to the optician,

231.

Prescriptions

A patient with a red Maddox rod with the cylinders orientated horizontally placed over her left eye. What does she see when she views a distant white fixation light?

White light, vertical red line

Red light, horizontal red line

White light, horizontal red line

Red light, vertical red line

232.

Astigmatism

Which of the following is an advantage of rigid gas permeable (RGP) contact lenses over soft lenses?

Greater initial comfort

Higher oxygen permeability

Does not require lens care

Reduced risk of corneal hypoxia

233.

Astigmatism

Which type of lens is used to correct astigmatism?

Cylindrical lens

Prism lens

Spherical lens

Plano-convex lens

234.

Astigmatism

In against-the-rule (ATR) astigmatism, the steepest meridian is located at approximately:

180°

45°

135°

90°

235.

Astigmatism

In simple myopic astigmatism, how does light focus?

Both focal points are in front of the retina.

Both focal points are behind the retina.

One focal point is on the retina, and the other is behind the retina.

One focal point is on the retina, and the other is in front of the retina.

236.

Astigmatism

What type of astigmatism is more commonly seen in older adults?

With-the-rule astigmatism

Oblique astigmatism

Against-the-rule astigmatism

Irregular astigmatism

237.

Astigmatism

In a cylindrical lens, where does the full power of the lens act?

At 45° to the axis

Perpendicular to the axis

Along the axis

Evenly across the entire lens

238.

Astigmatism

In a patient with regular astigmatism, how are the principal meridians positioned?

Parallel to each other

At 30-degree intervals

Perpendicular to each other

Randomly aligned

239.

Astigmatism

Where does a cylindrical lens exert its refractive power?

At the center of the lens

Equally across the entire lens

Along the axis of the lens

Perpendicular to the axis of the lens

240.

Astigmatism

A patient’s vision improves with a stenopaic slit placed at 90°. What type of refractive error does this suggest?

Simple hyperopia

Against-the-rule astigmatism

Simple myopia

With-the-rule astigmatism

241.

Astigmatism

Which of the following is used to manage keratoconus?

Rigid contact Lenses

LASEK

LASIK

Toric lenses

242.

Astigmatism

In simple hypermetropic astigmatism?

Both focal lines are in front of the retina

One focal line is on the retina whilst the other is behind it

Both focal lines are behind the retina

The focal lines are straddling the retina

243.

Astigmatism

Which of the following prescriptions is an example of 'with the rule' astigmatism?

-5.25 DS/ +2.50 DC axis 180

-1.50 DS/ -1.00 DC axis 45

+3.50 DS/ -0.75 DC axis 90

+3.00 DS/ +2.25 DC axis 85

244.

Astigmatism

Keratoconus most likely causes?

Refractive myopia

Refractive hypermetropia

Axial hypermetropia

Axial myopia

245.

Astigmatism

If rays of light from all meridians come into focus behind the retina, this is called?

Simple hypermetropic astigmatism

Compound myopic astigmatism

Compound hypermetropic astigmatism

Simple myopic astigmatism

246.

Low Vision Aids

Which low vision aid can help a patient with Age Related Macular Degeneration watch TV?

Hubble telescope

Magnifying glass

loop magnifiers

Galilean telescope

247.

Low Vision Aids

What is the primary purpose of low vision aids in the management of patients with visual impairment?

To treat underlying eye diseases

To restore normal vision

To eliminate the need for corrective lenses

To magnify images for clearer vision

248.

Low Vision Aids

Which of the following low vision aids is best suited for improving distance vision in individuals with low vision?

Reading glasses

Magnification spectacles

Telescopic lenses

Bifocal lenses

249.

Low Vision Aids

Which of the following low vision aids is most commonly used for close-up tasks such as reading?

Fresnel prisms

High-powered magnifying glasses

Visual field expanders

Telescopic lenses

250.

Low Vision Aids

Which of the following statements about the Galilean telescope is least likely?

The objective and eye piece lenses are separated by the difference between their focal lengths

It is composed of two convex lenses

It has an extremely narrow field of view

The image is typically dimmer than seen with the unaided eye

251.

Low Vision Aids

What role do prisms play in binoculars?

They invert and erect the image.

They increase the brightness of the image.

They reduce chromatic aberration.

They allow light to be focused at a single point.

252.

Low Vision Aids

Which of the following best describes the image produced by a Galilean telescope?

Virtual, inverted, magnified, at the sum of the focal lengths of the object and eyepiece lens

Virtual, erect, magnified, at the sum of the focal lengths of the objective and eyepiece lens

Virtual, inverted, magnified, at infinity

Virtual, erect, magnified at infinity

253.

Low Vision Aids

Which optical application commonly uses a plano-convex lens?

Camera telephoto lens

Magnifying glass

Optical fiber focusing

Myopia correction

254.

Clinical

Which of the following is not associated with myopia?

Congenital glaucoma

RRD

Uveal effusion syndrome

ROP

255.

Clinical

Which of the following is used to distinguish between open and closed angle glaucoma?

Perimetry

Gonioscopy

Fundoscopy

Tonometry

256.

Clinical

What investigation is used to measure corneal curvature?

Tonometry

Pachymetry

Keratometry

Perimetry

257.

Clinical

A patient with presbyopia says he can now see without his reading glasses, Which cataract does the patient have?

Cortical

Nuclear sclerotic

Anterior subcapsular

Posterior subcapsular

258.

Clinical

Which of the following structures is affected leading to presbyopia?

Zonules

Lens

Iris

Cornea

259.

Clinical

Which of the following factors increases the risk of infection in a patient using extended wear contact lenses?

Intact corneal epithelium

Switching to daily -wear contacts

Exposure to smoke

Normal eyelid function

260.

Clinical

Regarding the prevalence of myopia (of at least -0.5 dioptres):

It is lower in adults than in young children

Time spent outdoors as a child is a protective factor agains myopia

It is high in white Europeans compared to other ethnicities

Myopis tends to decrease with nuclear sclerosis of the lens

261.

Clinical

A child has a cycloplegia refraction 0D +6.00D, OS +2.00. What is the best way to manage the anisometropia?

Occlusion therapy

Paleoptic therapy

Full correction

Partial correction

262.

Clinical

Which lens can be used to examine the anterior chamber angle?

Wide field lens

Hruby lens

90D lens

Three mirror lens

263.

Clinical

Which of the following indirect ophthalmoscopy lenses gives the greater magnification?

15 D

20 D

28 D

30 D

264.

Clinical

How does corneal edema primarily affect vision?

Induces myopia

Increases light scatter

Enhances contrast sensitivity

Causes hyperopia

265.

Clinical

Which of the following is a common optical correction for presbyopia?

Progressive addition lenses (PALs)

Single-vision myopic glasses

Cylindrical lenses

Plano convex lenses

266.

Clinical

What is the primary cause of presbyopia?

Loss of lens elasticity

Weakening of the extraocular muscles

Corneal steepening

Increase in axial length

267.

Clinical

Which factor is least likely to influence the onset of presbyopia?

Age

Geographic location

Gender

Refractive error

268.

Spherical Lenses

How is the image formed by a convex lens of an object located inside the first focal point best described?

Inverted, real, outside the second focal point, magnified

Erect, real, inside age second focal point, diminished

Erect, virtual, further from lens than object, magnified

Inverted, virtual, at infinity, diminished

269.

Spherical Lenses

What role does a concave lens play in a Keplerian telescope?

It enhances color contrast by removing chromatic aberration

It magnifies the image without altering the focal length

It corrects the inverted image formed by the convex objective lens

It increases the field of view while maintaining image size

270.

Spherical Lenses

For a convex lens, placing an object outside the first principle focus results in an image that is

Magnified, inverted, virtual

Inverted, real

Erect, real

Enlarged, erect, virtual

271.

Spherical Lenses

A higher refractive index lens has which of the following advantages?

Reduced lens thickness

Increased lens thickness

Increased spherical aberrations

Increased chromatic aberration

272.

Spherical Lenses

The image formed by a thin concave lens is?

Virtual, inverted, diminished at infinity

Virtual, erect, diminished, inside the second focal point

Real erect, magnified, further from the lens than the object

Real, inverted, magnified, outside the second focal point

273.

Spherical Lenses

Tilting a spherical lens can induce which type of optical effect?

Elimination of aberrations

No effect

Induced prism

Reduced power

274.

Spherical Lenses

What happens when the curvature of a spherical lens increases?

The lens starts to behave like a prism instead of a spherical lens

The focal length increases, reducing the lens’s optical power

The focal length decreases, making the lens more powerful

The refractive index of the lens material changes

275.

Spherical Lenses

Which factor increases the optical power of a spherical lens, assuming the shape remains the same?

Reducing the curvature of the lens surfaces

Using a material with a higher refractive index

Increasing the focal length of the lens

Decreasing the thickness of the lens

276.

Spherical Lenses

What type of image is always produced by a concave (diverging) spherical lens?

Virtual, inverted, and same size as the object

Virtual, upright, and smaller than the object

Real, upright, and larger than the object

Real, inverted, and magnified

277.

Spherical Lenses

Which factor increases the optical power of a spherical lens, assuming the shape remains the same?

Decreasing the thickness of the lens

Reducing the curvature of the lens surfaces

Increasing the focal length of the lens

Using a material with a higher refractive index

278.

Spherical Lenses

Which statement is true regarding the difference between a biconcave and a plano-concave lens?

A plano-concave lens has equal power on both sides

A biconcave lens forms only real images

A biconcave lens has two concave surfaces and more negative power

A plano-concave lens is used to converge light rays

279.

Spherical Lenses

What happens to the focal length of a convex lens when it is submerged in water?

It remains the same because focal length is a material property

It depends only on the lens curvature, not the surrounding medium

It decreases because water enhances light bending

It increases because the refractive index contrast between the lens and water is reduced

280.

Jokes

😉 Why do people randomly test themselves for color blindness online?

Because they want to prove their friends wrong in an argument about "blue or green?"

Because they need to know whether they’d survive as a bomb defuser in an action movie.

Because it’s a convenient way to procrastinate at work.

Because they saw a meme that convinced them they’ve been colorblind their whole life.

281.

Jokes

😉 What’s the real reason optometrists get excited about astigmatism?

Because prescribing cylindrical correction makes them feel like wizards.

Because they secretly enjoy watching patients struggle with JCC testing.

Because saying “with-the-rule astigmatism” makes them feel fancy.

Because it’s a good excuse to show off their maths skills.

282.

Jokes

😉 What is the most common reaction after LASIK surgery?

“Wow, I can see! Time to read the fine print on my medical bills.”

“So… I paid thousands of dollars and now I have dry eyes forever?”

“Can I get a refund if I still need glasses?”

“My vision is so clear, I can now see all my life mistakes.”

283.

Properties of Light

A beam of light passes from air into glass at an angle. What happens to its frequency?

It increases.

It decreases.

It becomes zero.

It remains the same.

284.

Properties of Light

Which of the following is least likely to happen when constructing a correct ray diagram?

At least two rays are required to locate an image.

If the rays appear to diverge, a virtual image is formed.

Rays that do not intersect will eventually converge if extended.

The image forms where the reflected or refracted rays intersect.

285.

Properties of Light

Destructive interference is most likely in:

Antireflective lens coatings

Corneal endothelium

Corneal epithelium

Refraction

286.

Properties of Light

When light moves from air to water and travels towards the normal at the interface, which of the following is more likely to happen?

The light will undergo total internal reflection.

The light will bend away from the normal

The light will not bend at all.

The light will bend towards the normal.

287.

Properties of Light

Which statement about the speed of light is correct?

Light speeds up when entering a denser medium.

Light travels fastest in water.

Light slows down when entering a denser medium.

Light travels at the same speed in all mediums.

288.

Properties of Light

Which of the following terms best describes a substance which only allows the transmission of light in an incident plane aligned with its structure, by absorbing other light waves?

Scattering

Mirrored

birefringent

Dichroic

289.

Properties of Light

Which of the following is most likely the correct rule for drawing a principal ray in a concave mirror ray diagram?

A ray incident at the mirror surface always travels straight without reflection.

A ray passing through the centre of curvature (C) reflects at a random angle.

A ray parallel to the principal axis reflects through the center of curvature (C).

A ray passing through the focal point (F) reflects parallel to the principal axis.

290.

Properties of Light

Which change is most likely when a ray of light passes into a denser medium?

Velocity and frequency

Velocity only

Velocity and plane

Frequency and plane

291.

Properties of Light

Which definition most likely describes radiant flux?

The amount of light emitted from a source

The intensity if light emitted from a source

The amount of light falling in a surface

The amount of light reflected from a surface

292.

Properties of Light

The image of an object formed by reflection at a plane surface is least likely to be?

Laterally inverted

Virtual

Erect

Diminished

293.

Properties of Light

How is surface illumination related to the distance from the light source?

Inversely proportional

Directly proportional to the square root

Directly proportional

Inversely proportional the square root

294.

Properties of Light

Regarding optical radiation, which of the following is least likely?

The energy of a photon is directly proportional to its wavelength

The wavelength of light decreases as it enters a transparent material from a vacuum

Light emitted through fluorescence typically has a longer wavelength than the excitation light that trigger it

Shorter wavelengths undergo increased scatter

295.

Properties of Light

What causes the appearance of a secondary rainbow?

Diffraction of light waves

Multiple internal reflections inside raindrops

A different type of water droplet composition

A change in the sun’s intensity

296.

Properties of Light

Wavelength is best defined as?

The maximum displacement of an imaginary particle on the wave from the baseline

Any portion of the cycle

One complete oscillation

The distance between two symmetrical parts of the wave motion

297.

Properties of Light

What type of reflection occurs on a rough surface?

Diffuse reflection

Polarized reflection

Total internal reflection

Specular reflection

298.

Properties of Light

What does polarized light consist of?

Light waves with equal wavelengths

Light waves with reduced intensity

Light waves oscillating in multiple planes

Light waves oscillating in a single plane

299.

Properties of Light

Total internal reflection occurs is most likely if the incident ray strikes the interface of media at?

The critical angle

An angle greater than the critical angle

90 degrees

An angle less than the critical angle

300.

Properties of Light

The most likely unit of illuminance is?

Lux (human per square metre)

Watts per steradian

Lumen

Cadelas (lumen per steradian)

301.

Properties of Light

Which catastrophic image is most likely to form an inverted image?

Add description here!

Posterior corneal surface

Anterior lens surface

Posterior lens surface

Anterior corneal surface

302.

Properties of Light

Which type of light wave carries the most energy?

Blue light

Red light

Ultraviolet light

Infrared light

303.

Properties of Light

Which of the following statements about convave lenses is TRUE?

They converge parallel light rays to a focal point

They cause light to diverge

They are used to correct myopia

They always produce virtual images

304.

Properties of Light

Which of the following correctly describes light?

It requires a medium to travel.

It is a longitudinal wave.

It can exhibit both wave and particle properties.

It travels at the same speed in all materials.

305.

Properties of Light

Which of the following factors affects the scattering of light in the eye?

Lens elasticity

Corneal thickness

Wavelength of light

Intraocular pressure

306.

Properties of Light

What is the main law governing the reflection of light?

Fermat’s Principle

Brewster’s Law

Law of Equal Angles

Snell’s Law

307.

Properties of Light

What happens to light as it moves from a less dense medium (air) to a denser medium (cornea)?

It speeds up

It slows down and bends toward the normal

It bends away from the normal

It remains unaltered

308.

Properties of Light

Which of the following pairs is matched correctly?

Prism diopter-meters per centimetre

Dioptre-meter

Wavelength-nanometers

Refractive index-meters per second

309.

Properties of Light

Which of the following statements about convex lenses is TRUE?

They are used to correct myopia

They converge parallel light rays to a focal point

They always produce virtual images

They cause light to diverge

310.

Properties of Light

Which optical principle explains the formation of mirages?

Refraction

Reflection

Diffraction

Dispersion

311.

Properties of Light

Which color of visible light has the shortest wavelength?

Green

Yellow

Red

Blue

312.

Properties of Light

When the angle of incidence is greater than the critical angle?

Total Internal reflection occurs

Total external refraction occurs

Reflection mostly occurs with some refraction

The angle of incidence cannot be greater than the critical angle