Master ophthalmology mcqs Clinical Optics & Ophthalmic Instruments with MCQ Zone – Q241–280 covering spectacle lenses, contact lenses, IOL optics, aberration correction, and optical aids. NEET PG, AIIMS, NEXT & Optometry exam-ready MCQs with detailed explanations.View More Ophthalmology MCQ
This part focuses on lens design, contact lenses, IOL optics, anti-reflective coatings, aberration control, and optical aids used in ophthalmic practice — all accurate and exam-level (NEET PG, NEXT, AIIMS, MRCSEd, Optometry exams, Ophthalmic officers, exams Like RRB and DHS).
Spectacle Lens Design & Aberration Control ophthalmology mcqs
Q241. The main purpose of aspheric lenses is:
A. Cosmetic appearance
B. Reduce spherical aberration
C. Increase magnification
D. Reduce lens weight only
View Answer
B. Reduce spherical aberration ✅ Exp: Aspheric surfaces flatten peripherally, minimizing aberrations
Q242. Aspheric lenses provide:
A. Wider field with less distortion
B. Narrower field
C. No optical benefit
D. Increased chromatic error
View Answer
A. Wider field with less distortion ✅ Exp: Improved image quality and thinness.
Q243. The “base curve” of a spectacle lens refers to:
A. Front surface curvature
B. Back surface curvature
C. Lens thickness
D. Axis orientation
View Answer
A. Front surface curvature ✅ Exp: Base curve determines lens shape and optical behavior.
Q244. A flatter base curve results in:
A. Reduced magnification and thickness
B. Increased aberration
C. Increased magnification
D. Reduced field
View Answer
A. Reduced magnification and thickness ✅ Exp: Cosmetic and optical advantages in minus lenses.
Q245. Meniscus lens has:
A. One convex and one concave surface
B. Both convex
C. Both concave
D. Flat surfaces
View Answer
A. One convex and one concave surface ✅ Exp: Combines optical advantages of both surfaces.
Q246. Pantoscopic tilt refers to:
A. Forward tilt of spectacle lens
B. Backward tilt
C. Side rotation
D. Decentration
View Answer
A. Forward tilt of spectacle lens ✅ Exp: Typically 8–12° for optimal field and minimal distortion.
Q247. Effective power of tilted lens changes due to:
A. Oblique astigmatism
B. Chromatic aberration
C. Decentration
D. Prism effect
View Answer
A. Oblique astigmatism ✅ Exp: Tilting introduces induced cylinder power.
Q248. The vertex distance is the:
A. Distance from back surface of lens to cornea
B. Between both lenses
C. Frame gap
D. Pupil distance
View Answer
A. Distance from back surface of lens to cornea ✅ Exp: Important for high-power lenses in refraction accuracy.
Q249. For high minus lenses, vertex distance should be:
A. Minimum
B. Maximum
C. Moderate
D. Irrelevant
View Answer
A. Minimum ✅ Exp: Closer lens reduces minification and aberration.
Q250. For high plus lenses, vertex distance should be:
A. Minimum
B. Slightly greater
C. Maximum
D. Irrelevant
View Answer
B. Slightly greater ✅ Exp: Slight distance prevents excessive magnification.
ophthalmology mcqs
Q251. Antireflective coating works by:
A. Interference of light waves
B. Polarization
C. Reflection cancellation only
D. Absorption
View Answer
A. Interference of light waves ✅ Exp: Destructive interference reduces glare from lens surfaces.
Q252. Hard coating on lenses primarily improves:
A. Scratch resistance
B. Optical clarity
C. Color transmission
D. Anti-fog property
View Answer
A. Scratch resistance ✅ Exp: Protects from surface abrasions on resin lenses.
Q253. Polarized lenses reduce:
A. Reflected glare
B. Light transmission
C. Chromatic error
D. Distortion
View Answer
A. Reflected glare ✅ Exp: Block horizontally polarized light reflected from surfaces.
Q254. Photochromic lenses darken due to:
A. UV activation
B. Temperature
C. Infrared light
D. Moisture
View Answer
A. UV activation ✅ Exp: Silver halide molecules darken under UV exposure.
Q255. Polycarbonate lenses are preferred because:
A. Impact resistant & light
B. Heavy and thick
C. Easily scratched
D. Expensive only
View Answer
A. Impact resistant & light ✅ Exp: Ideal for children and safety spectacles.
Q256. Refractive index of cornea ≈
A. 1.336
B. 1.4
C. 1.33
D. 1.3
View Answer
A. 1.336 ✅ Exp: Average value for optical calculations.
Q257. Purpose of contact lens:
A. Correct refractive error at corneal plane
B. Replace spectacles cosmetically
C. Reduce accommodation
D. Improve tear film
View Answer
A. Correct refractive error at corneal plane ✅ Exp: Eliminates vertex distance effects and prismatic distortion.
Q258. Rigid gas permeable lenses correct:
A. Irregular astigmatism
B. Simple myopia only
C. Hyperopia
D. Presbyopia
View Answer
A. Irregular astigmatism ✅ Exp: Create a regular refracting surface over irregular cornea.
Q259. Tear lens formed between cornea and RGP acts as:
A. Additional refractive surface
B. Absorptive medium
C. Diffuser
D. Neutral film
View Answer
A. Additional refractive surface ✅ Exp: Alters effective refractive power depending on curvature.
Q260. Soft contact lenses primarily correct:
A. Regular refractive errors
B. Irregular astigmatism
C. Aphakia
D. Keratoconus
View Answer
A. Regular refractive errors ✅ Exp: Conform to corneal shape; unsuitable for irregular surfaces.
ophthalmology mcqs
Q261. Contact lens power adjustment vs spectacle:
A. Reduced plus power for hyperopia
B. Increased minus for myopia
C. No change
D. Always more plus
View Answer
A. Reduced plus power for hyperopia ✅ Exp: Vertex distance difference alters required power.
Q262. Central corneal flattening in contact lens users may indicate:
A. Overwear or tight lens
B. Good fit
C. Loose lens
D. Low oxygen
View Answer
A. Overwear or tight lens ✅ Exp: Pressure effect on corneal curvature.
Q263. Fluorescein pattern under RGP lens checks:
A. Lens fit
B. Tear volume
C. Refractive error
D. Oxygen permeability
View Answer
A. Lens fit ✅ Exp: Pooling and touch zones reveal alignment.
Q264. Excessive central pooling =
A. Steep fit
B. Flat fit
C. Good fit
D. Edge lift
View Answer
A. Steep fit ✅ Exp: Lens curvature steeper than cornea.
Q265. Edge lift in fluorescein pattern =
A. Flat fitting lens
B. Steep fit
C. Proper alignment
D. Tight lens
View Answer
A. Flat fitting lens ✅ Exp: Flat lens leaves peripheral gap.
Q266. Oxygen permeability of contact lenses denoted by:
A. Dk
B. Ka
C. Rn
D. Di
View Answer
A. Dk ✅ Exp: Diffusion coefficient × solubility constant.
Q267. Dk/t represents:
A. Oxygen transmissibility
B. Water content
C. Tear exchange
D. Refractive index
View Answer
A. Oxygen transmissibility ✅ Exp: Accounts for material permeability and thickness.
Q268. Contact lens material with highest oxygen transmission:
A. Silicone hydrogel
B. PMMA
C. HEMA
D. Polyvinyl
View Answer
A. Silicone hydrogel ✅ Exp: Silicone allows high O₂ diffusion.
Q269. IOL power formula based on corneal curvature and axial length:
A. SRK formula
B. Donders’ rule
C. Helmholtz equation
D. Snell’s law
View answer
A. SRK formula ✅ Exp: SRK = A – 2.5L – 0.9K (simplified).
Q270. “A-constant” in IOL formula refers to:
A. Lens position factor
B. Corneal index
C. Axial length
D. Keratometry error
View Answer
A. Lens position factor ✅ Exp: Adjusted for surgical technique and lens model.
ophthalmology mcqs
Q271. Average adult IOL power ≈
A. +20 D
B. +10 D
C. +25 D
D. +30 D
View Answer
A. +20 D ✅ Exp: Range 18–22 D for emmetropic eye.
Q272. Posterior chamber IOL placed:
A. In capsular bag
B. In anterior chamber
C. In vitreous
D. Under conjunctiva
View Answer
A. In capsular bag ✅ Exp: Standard modern placement after cataract extraction.
Q273. Effective lens position (ELP) mainly affects:
A. Postoperative refraction
B. Axial length
C. Astigmatism
D. Pupil size
View Answer
A. Postoperative refraction ✅ Exp: Changes vergence of IOL’s optical system.
Q274. Aspheric IOLs reduce:
A. Spherical aberration
B. Chromatic dispersion
C. Glare
D. Tilt
View Answer
A. Spherical aberration ✅ Exp: Designed with modified curvature profiles.
Q275. Multifocal IOLs provide:
A. Multiple focal points
B. Single distant focus
C. Adjustable power
D. Continuous zoom
View Answer
A. Multiple focal points ✅ Exp: Combine zones for near and distance vision.
Q276. Toric IOL corrects:
A. Astigmatism
B. Presbyopia
C. Hyperopia
D. Myopia only
View Answer
A. Astigmatism ✅ Exp: Cylinder power incorporated into lens design.
Q277. Blue-blocking IOLs designed to:
A. Filter high-energy blue light
B. Reduce UV transmission only
C. Enhance chromatic aberration
D. Increase brightness
View Answer
A. Filter high-energy blue light ✅ Exp: Protect macula from phototoxicity.
Q278. IOL decentration causes:
A. Coma & glare
B. Chromatic error
C. Reduced magnification
D. Increased field
View Answer
A. Coma & glare ✅ Exp: Off-axis positioning distorts image symmetry.
Q279. Posterior capsule opacification caused by:
A. Lens epithelial cell proliferation
B. Infection
C. Corneal edema
D. IOL tilt
View Answer
A. Lens epithelial cell proliferation ✅ Exp: Secondary cataract after extracapsular surgery.
Q280. Nd:YAG laser used to treat:
A. Posterior capsular opacification
B. Astigmatism
C. Myopia
D. Glaucoma
View Answer
A. Posterior capsular opacification ✅ Exp: Capsulotomy creates central opening to restore vision.
ophthalmology mcqs
