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.
Patent No.:
Date of Patent:
Dec. 30, 1986
Filed:
Apr. 18, 1985
Lars Karlsson, Taby, SE;
Pharos AB, Lidingo, SE;
Abstract
In an optical scanning device in which the active scanning means comprises a rotating polygon provided with a plurality of reflecting facets, the so-called optical invariant ##EQU1## wherein .phi. is the aperture of the scanning device, .alpha. is the field angle of the scan, the NETD is the so-called Noise Equivalent Difference Temperature, is increased by passing the beam path against the polygon so as to be reflected therefrom a multiple of times, and therein with substantially complete tracking of the facets while substantially filling the same completely over the full extension of the facets, with the exception of that facet located nearest the beam detector. This is effected with the aid of stationary beam-deflecting optical means which cause the mutual reproductions between facets with reflection of substantially full extension in the rotary direction of the polygon to take place against diametrically opposed facets at a magnification of approximately -1.