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:
Aug. 29, 2017
Filed:
Aug. 09, 2016
Topcon Corporation, Tokyo, JP;
Akinobu Sugiura, Tokyo, JP;
TOPCON CORPORATION, Tokyo, JP;
Abstract
In an automatic survey instrument that divides reflected light from a target into collimation light, range-finding light, and tracking light, a configuration of an optical absorption filter for visible light absorption to be used for SN ratio improvement is simplified, and deterioration in automatic tracking performance due to a defect inside the optical absorption filter is suppressed. Between two prisms () defining a second reflecting surface () of a dichroic prism () through which reflected light from a target enters, an optical absorption filter () that absorbs a wavelength band of visible light is inserted, and the second reflecting surface () is formed at a border between a rear surface of the optical absorption filter () with respect to a light propagation direction and a surface of the prism () on the rear side of the optical absorption filter in the light propagation direction.