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:
Feb. 17, 2009
Filed:
Jan. 03, 2008
Futoshi Osada, Kanagawa, JP;
Futoshi Osada, Kanagawa, JP;
Sokkia Co., Ltd., Kanagawa, JP;
Abstract
An electric optical distance meter is provided that makes an input power level of a reference light entering a light receiving device via an internal optical path comparable between low and high reflectivity targets. The electric optical distance meter has a shutterfor switching between an external optical path Po, through which a distance measuring light emitted by a light source is placed to and from a target, and the internal optical path Pi is placed from the light source to the light receiving device, where the shutter has: a rotating axis; blocking plateswhich are arranged at two locations symmetric with respect to the rotating axis, and alternately block the respective distance measuring lights L entering the external optical path and the internal optical path; and an attenuation platewhich is placed at one of the two locations where the blocking plates are not arranged and between the blocking plates, and attenuates the distance measuring light entering the internal optical path when the target is of a low reflectivity.