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:
Sep. 28, 2004
Filed:
Aug. 15, 2003
Kenji Kaneko, Tokyo, JP;
PENTAX Precision Co., Ltd., Tokyo, JP;
Abstract
A survey point indicating instrument, for recognizing a line of sight visually, includes a collimating lens, two light sources being positioned so that optical axes of the two light sources intersect each other on an optical axis of the collimating lens at a focal point of the collimating lens; a driving circuit for controlling light emissions of the two light sources independently from each other; and a light shield plate having a slit, and positioned between the focal point and the two light sources so that light rays emitted from each of the two light sources to travel in an area between the optical axes are allowed to pass through the slit while other light rays emitted from each of the two light sources are cut off by the light shield plate to prevent the other light rays from traveling outside the area between the optical axes.