The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.

The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.

Date of Patent:
Nov. 11, 1986

Filed:

Mar. 14, 1985
Applicant:
Inventors:

Mitsuo Chikano, Tokyo, JP;

Yuji Nakajima, Tokyo, JP;

Assignee:

Hoya Corporation, Tokyo, JP;

Attorney:
Primary Examiner:
Int. Cl.
CPC ...
G02B / ; G02B / ;
U.S. Cl.
CPC ...
350-16 ; 350316 ; 350318 ;
Abstract

A camera filter is provided with an ultraviolet ray absorbing substrate, on which is deposited an evaporated film which transmits blue and green light, but which sharply attenuates a portion of the red light in the higher wavelength range. Particularly, the wavelength at which the transmission factor reaches 50% is in a range from 640 to 700 nm. The evaporated film is formed on one surface of the substrate, typically the inner surface thereof relative to the camera lens, and the filter is fitted to a frame which may be suitably attached to the camera lens.


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