Claims
- 1. An imaging system for automatically focusing an image for recordation onto an illumination surface, the system comprising:a first illumination source for producing a first illumination field; a diffractive modulator for modulating the first illumination field received from the first illumination source; a first collimating lens for collimating the first illumination field received from the diffractive modulator; a pupil for passing the first illumination field from the first collimating lens; a first IR blocking filter for shielding the first collimating lens from light reflected from the imaging surface; a focal lens for focusing light received from the pupil onto the imaging surface; and an autofocus system comprising: a second illumination source for producing a second illumination field: a second collimating lens for collimating the second illumination field received from the second illumination source; a beam splitter and mirrors for directing the second illumination field from the second collimating lens through the first collimating lens, the pupil and the focal lens to the imaging surface, a portion of the second illumination field being reflected from the imaging surface and passing through the focal lens, the pupil and the first collimating lens; a second IR blocking filter for filtering the reflected portion of the second illumination field; a cylindrical lens for receiving the reflected portion from the second IR blocking filter and introducing an astigmatism that transforms a round spot into two orthogonal ellipses; a quad cell sensor for receiving the reflected portion from the cylindrical lens to produce a sensor output signal; and a control assembly for adjusting a focal point of the optical imaging system responsive to said sensor output signal.
Parent Case Info
This application is a continuation-in-part application of U.S. patent application Ser. No. 09/712,860 filed Nov. 15, 2000 now U.S. Pat. No. 6,504,137.
US Referenced Citations (8)
Foreign Referenced Citations (1)
Number |
Date |
Country |
1285870 |
Aug 1972 |
GB |
Continuation in Parts (1)
|
Number |
Date |
Country |
Parent |
09/712860 |
Nov 2000 |
US |
Child |
10/269406 |
|
US |