Position detecting method having reflectively scattered light pr

Details Position detecting method having reflectively scattered light pr Position detecting method having reflectively scattered light pr

1992-11-06

1993-07-20

Nelms, David C.

Radiant energy

Photocells; circuits and apparatus

Photocell controls its own optical systems

356401, G01N 2186

Patent

active

052296172

ABSTRACT:
A method of detecting the position of a substrate by using a grating pattern formed on the substrate is disclosed. In this method, a radiation beam is projected to the grating pattern by which a diffraction beam is produced and received by a sensor, wherein any reflectively scattered light from an edge of an outer peripheral part of the diffraction pattern is substantially prevented from being received by the sensor; and wherein an output signal from the sensor responsive substantially only to the diffraction beam from the grating pattern is used to determine the position of the substrate.

REFERENCES:
patent: 4211489 (1980-07-01), Kleinknecht et al.
patent: 4600309 (1986-07-01), Fay
patent: 4704033 (1987-11-01), Fay et al.
patent: 4948983 (1990-08-01), Maruyama et al.
patent: 4962318 (1990-10-01), Nishi

Affiliated with

Also associated with

Rating

Position detecting method having reflectively scattered light pr does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Position detecting method having reflectively scattered light pr, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Position detecting method having reflectively scattered light pr will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1762592