How you see with your eyes: part 3 the crystalline lens

This next topic will be about the Crystalline lens.

This part of the eye structure is located behind the Iris, where it sits around a muscle called the Ciliary body. The lens itself provides about 1/3 the the total refractive power of the eye, the other 2/3 is from the cornea. How the lens work is through a process called accommodation, meaning focusing ability of the eye. The lens basically flexes in and out to achieve that level of focus, it is a Biconvex structure, that can stretch out to focus up close and relaxes to focus far away.

It is also completely transparent and contains no blood vessels, it mainly gets its nutrients from a fluid called the aques humor. How it moves and flexes is due to the muscles surrounding the lens with are attached to tiny fibers called the Zonules, each time the muscle "flexes" it moves the lens shape. It achieves focusing by moving light either on the macula(fovea) or away from it. Just amazing how all that is communicated back and forth thru your brain!

In a later piece, I will discuss a condition where the lens loses the ability to focus and will then turn into Cataracts.
Until the next time!

If you have any comments or questions please post a reply !

Read my previous post

How you see with your eyes: part 1
How you see with your eyes:part 2