# Homework Help: Size of projected image on retina

1. Dec 20, 2011

### SoggyBottoms

1. The problem statement, all variables and given/known data
The eye sits a distance L above a horizontal plane filled with square tiles with sides of length B. Neglect the curvature of the retina. Find formulae for:

1) The width b of the projected image on the retina for a tile at distance D
2) The height c of the projected image on the retina for a tile at distance D
3) The area a of the projected image on the retina for a tile at distance D

http://img155.imageshack.us/img155/1661/46682727.jpg [Broken]

3. The attempt at a solution

1 & 2) $$\frac{BS}{\sqrt{D^2 + L^2}} = b = c$$

I get the same thing for both. Is this correct?

3) I would say a = bc, but there might be more to it?

Last edited by a moderator: May 5, 2017