Radiant energy – Photocells; circuits and apparatus – Photocell controls its own optical systems
Patent
1996-03-15
1998-02-03
Le, Que
Radiant energy
Photocells; circuits and apparatus
Photocell controls its own optical systems
2502013, 355 55, 396 79, G01J 120
Patent
active
057147493
ABSTRACT:
A focus detecting apparatus of the present invention comprises (a) an image projection unit which projects a first checking light through a first region out of two regions formed by splitting a space into two along a border plane including the optical axis of the objective optical system, onto the measured object to form an image of the light source thereon, and (b) an image detection unit which condenses a second checking light emerging from the image of the light source through the second region opposed to the first region with the border plane inbetween, on a light-receiving surface of a photodetector to form image of the measured object thereon. The image projection unit comprises a first converging optical system, which has a first refractive power in a first plane parallel to the border plane, which has a second refractive power substantially different from the first refractive power in a second plane parallel to the optical axis of the objective optical system and perpendicular to the border plane. The apparatus so arranged can be substantially free of influence of light scattering at a level-difference edge on the object surface and can maintain a high utilization factor of light, whereby it can detect the focus information of the objective optical system on the object with high accuracy.
REFERENCES:
patent: 3721827 (1973-03-01), Reinheimer
patent: 4798948 (1989-01-01), Neumann et al.
patent: 5440367 (1995-08-01), Suda
Mizuno Jiro
Otomo Masahiko
Yonezawa Yasuo
Le Que
Nikon Corporation
LandOfFree
Focus detecting apparatus and microscope apparatus equipped with does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Focus detecting apparatus and microscope apparatus equipped with, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Focus detecting apparatus and microscope apparatus equipped with will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-664825