Best focus determining method

Details Best focus determining method Best focus determining method

1996-07-24

1998-05-12

Young, Christopher G.

Radiation imagery chemistry: process, composition, or product th

Registration or layout process other than color proofing

430 30, 355 63, G03F 900

Patent

active

057502943

ABSTRACT:
Disclosed is a method of determining a best focus position or best exposure amount of a projection lens in an arrangement wherein a reticle is placed on a plane perpendicular to an optical axis of the projection lens, wherein a pattern having periodicity in a predetermined direction is provided on a surface of the reticle, wherein the pattern is transferred to a photosensitive substrate by the projection lens to form a printed pattern thereon. The method includes providing the pattern by using a plurality of zigzag openings of a constant line width, extending in a direction perpendicular to the predetermined direction and being arrayed with a constant periodicity along that direction, transferring the pattern to the photosensitive substrate sequentially with different focus positions to form plural printed patterns thereon, imaging the printed patterns upon an image pickup surface of photoelectrically converting means; calculating, from an imagewise signal produced by the photoelectrically converting means, information related to one frequency component of zigzag lines, constituting an outline of an image of the zigzag opening, and determining the best focus position on the basis of the information.

REFERENCES:
patent: 5044750 (1991-09-01), Shamble
patent: 5578401 (1996-11-01), Hwang
patent: 5610718 (1997-03-01), Sentoku et al.
patent: 5656403 (1997-08-01), Shieh

Affiliated with

Also associated with

Rating

Best focus determining method does not yet have a rating. At this time, there are no reviews or comments for this patent.

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

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-977940