Automatic focusing device

Details Automatic focusing device Automatic focusing device

1982-12-10

1985-04-09

Perkey, William B.

G03B 310

Patent

active

045098417

ABSTRACT:
The disclosed automatic focusing device operates by detecting a motor signal which is produced according to the lens movement and by forming a limit signal when the motor signal is not produced for a period longer than a predetermined time. A reference signal forming circuit produces a reference signal corresponding to the shift in focus per unit time. The motor signal is compared with the reference signal and the lens drive speed is adjusted to reduce the difference between the two signals. The invention avoids a mechanical limit switch and maintains an unvarying shift in focus per unit time for different kinds of lenses.

REFERENCES:
patent: 4200378 (1980-04-01), Shenk

Affiliated with

Also associated with

Rating

Automatic focusing device does not yet have a rating. At this time, there are no reviews or comments for this patent.

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

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1166855