Boost your NEET PG ophthalmology mcq , AIIMS, and Optometry prep with MCQ Zone. Explore Chapter 4: Optics of Lenses & Ophthalmic Instruments (A.K. Khurana) Q201–240. Includes exam-ready questions on optical aberrations, corrective lenses, telescopes, entoptic phenomena, and photometry with detailed explanations.
This batch will include optical aberrations, corrective lenses, magnification systems, telescope principles, entoptic phenomena, and photometric concepts — all accurate, unique, and exam-ready (NEET PG / NEXT / AIIMS / Optometry / Ophthalmic officers).
Q201. Spherical aberration occurs when:
A. Peripheral rays focus differently from central rays
B. Light focuses at same point
C. Axial rays are scattered
D. Chromatic dispersion happens
View Answer
A. Peripheral rays focus differently from central rays ✅ Exp: Peripheral rays refract more → image blur.
Q202. Chromatic aberration results from:
A. Wavelength-dependent refraction
B. Lens curvature defect
C. Misalignment
D. Diffraction
View Answer
A. Wavelength-dependent refraction ✅ Exp: Different colors focus at different distances due to varying refractive indices.
Q203. Longitudinal chromatic aberration affects:
A. Image position along axis
B. Image shape
C. Color saturation
D. Size only
View Answer
A. Image position along axis ✅ Exp: Focal points of various wavelengths differ along optical axis.
Q204. Transverse chromatic aberration affects:
A. Image magnification and color fringing
B. Image brightness
C. Field of view
D. Lens thickness
View Answer
A. Image magnification and color fringing ✅ Exp: Causes lateral displacement of colors.
Q205. Astigmatism in optics occurs due to:
A. Unequal curvature in lens meridians
B. Spherical lens
C. Chromatic error
View Answer
A. Unequal curvature in lens meridians ✅ Exp: Different meridians focus at different points.
Q206. Coma is an aberration causing:
A. Comet-shaped off-axis images
B. Spherical blur
C. Axial distortion
D. Color separation
View Answer
A. Comet-shaped off-axis images ✅ Exp: Light from off-axis point forms tail-like image.
Q207. Distortion arises due to:
A. Unequal magnification across field
B. Chromatic dispersion
C. Refraction difference
D. Spherical error
View Answer
A. Unequal magnification across field ✅ Exp: Barrel or pincushion effects in wide-field lenses.
Q208. The Seidel aberrations include all except:
A. Spherical
B. Chromatic
C. Coma
D. Astigmatism
View Answer
B. Chromatic ✅ Exp: Classical Seidel (monochromatic) aberrations exclude chromatic error.
Q209. Use of diaphragm or aperture stop helps reduce:
A. Spherical aberration
B. Chromatic aberration
C. Distortion
D. Astigmatism
View Answer
A. Spherical aberration ✅ Exp: Restricts peripheral rays.
Q210. Achromatic doublet lens minimizes:
A. Chromatic aberration
B. Coma
C. Astigmatism
D. Spherical aberration
View Answer
A. Chromatic aberration ✅ Exp: Combines convex + concave lenses of different glass types.
NEET PG ophthalmology mcq
Q211. A prism deviates light:
A. Toward base
B. Toward apex
C. Away from base
D. Randomly
View Answer
A. Toward base ✅ Exp: Apparent image shifts toward apex; light bends to base.
Q212. Prism power (in prism diopters) defined as:
A. 1 cm deviation at 1 m
B. 1 mm deviation at 1 cm
C. 1 degree deviation
D. 10 cm deviation
View Answer
A. 1 cm deviation at 1 m ✅ Exp: 1∆ = deviation of 1 cm at 1 m.
Q213. Base-out prism used for:
A. Esotropia correction
B. Exotropia
C. Hypertropia
D. Myopia
View Answer
A. Esotropia correction ✅ Exp: Shifts image outward → relaxes convergence.
Q214. Base-in prism used for:
A. Exotropia
B. Esotropia
C. Hypertropia
D. Hypotropia
View Answer
A. Exotropia ✅ Exp: Helps convergence excess cases.
Q215. A 25-year-old woman presents with pain, redness, and photophobia in one eye. On slit-lamp examination, there are keratic precipitates and cells in the anterior chamber. What is the most likely diagnosis?
A. Acute conjunctivitis
B. Acute anterior uveitis
C. Acute angle-closure glaucoma
D. Bacterial keratitis
View Answer
✅ Correct Answer: B. Acute anterior uveitis
Anterior uveitis presents with pain, redness (especially around the limbus), photophobia, and blurred vision. Slit-lamp findings include keratic precipitates, cells, and flare in the anterior chamber
Q216. Decentration of +2.00 D lens by 0.5 cm induces:
A. 1∆
B. 2∆
C. 0.5∆
D. 0.25∆
View Answer
A. 1∆ ✅ Exp: P = 0.5 × 2 = 1∆.
Q217. Fresnel prism made of:
A. Thin plastic sheets
B. Glass
C. Quartz
D. Fiber
View Answer
A. Thin plastic sheets ✅ Exp: Used for temporary or trial prism corrections.
Q218. A 60-year-old diabetic patient complains of gradual, painless loss of vision in both eyes. Fundoscopy shows microaneurysms, dot and blot hemorrhages, and hard exudates. What is the most likely diagnosis?
A. Proliferative diabetic retinopathy
B. Non-proliferative diabetic retinopathy
C. Hypertensive retinopathy
D. Macular degeneration
View Answer
✅ Correct Answer: B. Non-proliferative diabetic retinopathy
Non-proliferative diabetic retinopathy (NPDR) is characterized by microaneurysms, hemorrhages, and hard exudates without new vessel formation. It represents an early stage of diabetic retinal damage.
Q219. A 70-year-old man presents with sudden, painless loss of vision in one eye. Fundoscopy reveals a “blood and thunder” appearance with retinal hemorrhages and dilated tortuous veins. What is the most likely diagnosis?
A. Central retinal artery occlusion
B. Central retinal vein occlusion
C. Retinal detachment
D. Optic neuritis
View Answer
✅ Correct Answer: B. Central retinal vein occlusion
Q220. A +4 D objective and +20 D eyepiece produce magnification =
A. 5×
B. 4×
C. 10×
D. 2×
View Answer
A. 5× ✅ Exp: 20 / 4 = 5× (inverse for diopter ratio)
NEET PG ophthalmology mcq
Q221. Galilean telescope gives:
A. Upright image
B. Inverted image
C. Reversed image
D. Virtual only
View Answer
A. Upright image ✅ Exp: Convex objective + concave eyepiece yields erect image.
Q222. Keplerian telescope gives:
A. Inverted image
B. Upright
C. Virtual
D. Reduced field
View Answer
A. Inverted image ✅ Exp: Both lenses convex → real, inverted image.
Q223. Field of view in Galilean system:
A. Narrow
B. Wide
C. Large
D. Variable
View Answer
A. Narrow ✅ Exp: Concave eyepiece limits exit pupil → narrow field.
Q224. Low vision telescopes used for:
A. Distance vision improvement
B. Near vision only
C. Accommodation training
D. Binocular therapy
View Answer
A. Distance vision improvement ✅ Exp: Magnify distant images for central scotoma patients.
Q225. Magnification in Keplerian telescope can be increased by:
A. Increasing focal length of objective
B. Shorter eyepiece
C. Larger aperture
D. Longer tube only
View Answer
A. Increasing focal length of objective ✅ Exp: Larger objective → higher magnification.
Q226. Field illumination in Galilean telescope:
A. Brighter
B. Duller
C. Uniform
D. Distorted
View Answer
A. Brighter ✅ Exp: Fewer lenses → less light loss.
Q227. Binocular telescopes used in:
A. Low vision aids
B. Fundus exam
C. Perimetry
D. Tonometry
View Answer
A. Low vision aids ✅ Exp: Provide distance magnification with both eyes.
Q228. Disadvantage of Galilean telescope:
A. Narrow field of view
B. Image inversion
C. High chromatic aberration
D. Poor illumination
View Answer
A. Narrow field of view ✅ Exp: Limited exit pupil size reduces usable field.
Q229. Reading telescopes in low vision are mounted on:
A. Spectacle frames
B. Headband
C. Tripod
D. Handheld
View Answer
A. Spectacle frames ✅ Exp: Called “spectacle-mounted telescopes.”
Q230. Exit pupil lies:
A. At eyepiece in Galilean system
B. Beyond eyepiece in Keplerian
C. Inside objective
D. At retina
View Answer
A. At eyepiece in Galilean system ✅ Exp: Exit pupil determines brightness and ease of use.
NEET PG ophthalmology mcq
Q231. Entoptic phenomena are:
A. Visual sensations arising within eye
B. Optical illusions
C. Brain hallucinations
D. Retinal scotomas
View Answer
A. Visual sensations arising within eye ✅ Exp: Originates from structures of the eye itself.
Q232. Purkinje tree represents:
A. Retinal blood vessel shadows
B. Lens opacities
C. Corneal nerves
D. Floaters
View Answer
A. Retinal blood vessel shadows ✅ Exp: Seen under flickering light due to retinal vessel shadows.
Q233. Haidinger’s brushes due to:
A. Macular birefringence
B. Corneal reflection
C. Chromatic dispersion
D. Vitreous opacities
View Answer
A. Macular birefringence ✅ Exp: Blue–yellow fan seen with polarized light.
Q234. Blue field entoptic phenomenon:
A. Moving white dots due to leukocytes in retinal capillaries
B. Floaters
C. Flashes
D. Shadows
View Answer
A. Moving white dots due to leukocytes in retinal capillaries ✅ Exp: Observed when viewing bright blue light.
Q235. Moiré fringes arise from:
A. Overlapping gratings
B. Chromatic effect
C. Interference of light
D. Refraction
View Answer
A. Overlapping gratings ✅ Exp: Created when two repetitive patterns overlap.
Q236. Phosphenes are caused by:
A. Mechanical stimulation of retina
B. Light diffraction
C. Tear film
D. Lens reflection
View Answer
Exp: Visual sensation from pressure or electrical activity.
Q237. Luminous flux measured in:
A. Lumens
B. Lux
C. Candela
D. Foot-lambert
View Answer
A. Lumens ✅ Exp: Total light emitted by source.
Q238. Luminous intensity measured in:
A. Candela
B. Lumen
C. Lux
D. Watt
View Answer
A. Candela ✅ Exp: Light emitted per unit solid angle.
Q239. Illuminance (illumination) unit:
A. Lux
B. Candela
C. Lumen
D. Newton
View Answer
A. Lux ✅ Exp: Lumens per square meter.
Q240. Brightness of visual field (luminance) unit:
A. Candela/m²
B. Lux
C. Lumen
D. Watt
View Answer
A. Candela/m² ✅ Exp: Indicates surface brightness reaching the eye.
NEET PG ophthalmology mcq
