Title:
OPTICAL ELEMENT
Document Type and Number:
Japanese Patent JPS58202421
Kind Code:
A
Abstract:
An optical element for location between a source of radiation and a detector (13) includes a first optical surface (10) have a central transmissive area (11) and a surrounding area (12) reflective to radiation from direction of the detector (13). A second optical surface (15) is spaced from the first surface (10) towards the detector (13) and has a central reflective area (16) arranged to reflect radiation passing through area 11 towards the reflective area 12. A transmissive area (18) of the second surface (15) surrounds the central area (16), and is itself surrounded by a reflecting area (17) concentric with the detector (13) and forming a reflective shield for the detector.
Inventors:
HIRARII GIRU SHIRITSUTO
Application Number:
JP7309583A
Publication Date:
November 25, 1983
Filing Date:
April 27, 1983
Export Citation:
Assignee:
FERRANTI LTD
International Classes:
G01J5/08; G02B17/06; G02B17/08; (IPC1-7): G02B17/08
Attorney, Agent or Firm:
Warren G. Simor