Official websites use .gov
A
.gov website belongs to an official
government organization in the United States.
Secure .gov websites use HTTPS
A lock (
) or https:// means you've safely
connected to the .gov website. Share sensitive
information only on official, secure websites.
(a) Picture surface LR in physical space, with the eye at E. The diameter of the picture is d, its angular subtense in the visual field is α. (b) The configuration at left transformed into angle–log distance space. The location of the eye is at minus infinity, all visual rays are parallel. The circles concentric with the eye in physical space appear as the straight orthotomics of the visual rays. In this space the blue line is curved.
