PHYSIOLOGY - Accomodation Flashcards
What is the main refractive power of cornea and lens?
Cornea - +45D
Lens - +15D
Total = + 60D
What are the differences in light rays towards the eye from a distant object vs a near object?
distant object - parallel rays from infinity towards eye
near object - diverging rays from object towards eye therefore requires more converging power to focus on retina.
What is the definition of accomodation?
The necessary increase in the conergence power of the eyeball by increasing the refractive power of the crystalline lens, by increasing the curvature of its anterior surface –> accomodation.
How much does the anterior curvature radius change when in accomodation?
anterior surface radius curvature changes from 10mm to 6mm
posterior surface radius curvature remains the same at 10mm
What structure connects the ciliary body to the equator of the lens?
the suspensory ligament of lens
