Passive infrared detection system with substantially uniform sen

Details Passive infrared detection system with substantially uniform sen Passive infrared detection system with substantially uniform sen

1989-01-31

1990-04-24

Howell, Janice A.

Radiant energy

Invisible radiant energy responsive electric signalling

Infrared responsive

250342, G01J 508

Patent

active

049202685

ABSTRACT:
A passive infrared detection system includes a reflective optical system comprising a focusing element (e.g. an elliptical or parabolic reflector) having an apparent focal length dependent upon the displacement of incident rays from the optical axis of such element, and a plurality of planar reflectors arranged at different angles with respect to such optical axis to provide the detection system with a plurality of different zones of detection, each having a different maximum detection range associated with it. According to the invention, the planar reflectors are arranged with respect to the focusing element so that each planar reflector cooperates with a different portion of the focusing element to project onto an IR detector located at the focus of such focusing element a relatively constant size image of a given target located at the maximum detection range associated with that planar reflector. Such an optical system provides the detection system with more uniform sensitivity from one zone of detection to another.

REFERENCES:
patent: 4258255 (1981-03-01), Guscott
patent: 4514630 (1985-04-01), Takahashi
patent: 4709152 (1987-11-01), Muller et al.
patent: 4746906 (1988-03-01), Lederer

Affiliated with

Also associated with

Rating

Passive infrared detection system with substantially uniform sen does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Passive infrared detection system with substantially uniform sen, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Passive infrared detection system with substantially uniform sen will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-35786