Folded optical system for radiation detection device
US4689486A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 29, 1985 |
| Grant date | Aug 25, 1987 |
| Priority date | — |
| Expiry date | Nov 29, 2005 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S250/01
- WIPO fieldControl
- WIPO sectorInstruments
Abstract
A folded modular optical system adapted for use, for example, in a passive infrared intruder detection device for directing radiation from a plurality of discrete fields of view onto a radiation-sensitive detector comprises an elongated rectangularly-shaped spherical reflector and a multifaceted reflective element. The latter comprises a plurality of elongated, generally parallel, planar reflectors which serve to direct radiation onto different portions of the spherical reflector. To minimize the effects of spherical aberration, the planar reflectors are arranged so that the portions of the spherical reflector which they irradiate are substantially perpendicular to the longer dimension of the rectangularly-shaped spherical reflector. Preferably, each of the planar reflectors is canted relative to the others so that its field of view is substantially co-planar with those of the other planar reflectors. It is also preferred that the planar reflectors vary in size and, hence, light-gathering power as a function of the intended range of protection they provide.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.