Flatness measuring apparatus

Details Flatness measuring apparatus Flatness measuring apparatus

1980-12-11

1982-06-01

Punter, William H.

Optics: measuring and testing

By polarized light examination

With light attenuation

356376, 364571, G01B 1130, G01B 1124, G01C 2500

Patent

active

043324770

ABSTRACT:
A flatness measuring apparatus or the like for measuring the flatness of a thin specimen such as a wafer for producing semi-conductor devices by detecting, with a photoreceptor, the first-order time-differentiated signal of the reflection angle of a laser scanning beam representing the surface configuration and electrically integrating said signal in time, said apparatus being featured in having a signal forming apparatus for providing, in case said thin specimen is inclined from a standard position, a correction signal corresponding to the amount of said inclination.

REFERENCES:
patent: 3768910 (1973-10-01), Zanoni
patent: 3857637 (1974-12-01), Obenreder
patent: 3885875 (1975-05-01), Rosenfeld et al.

Affiliated with

Also associated with

Rating

Flatness measuring apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Flatness measuring apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Flatness measuring apparatus will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1847188