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:
May. 13, 2008
Filed:
Sep. 13, 2005
Masahiro Akiba, Yamagata, JP;
Kinpui Chan, Yamagata, JP;
Yasufumi Fukuma, Tokyo, JP;
Hiroyuki Otsuka, Tokyo, JP;
Hisashi Tsukada, Tokyo, JP;
Kazuhiko Yumikake, Tokyo, JP;
Masahiro Akiba, Yamagata, JP;
Kinpui Chan, Yamagata, JP;
Yasufumi Fukuma, Tokyo, JP;
Hiroyuki Otsuka, Tokyo, JP;
Hisashi Tsukada, Tokyo, JP;
Kazuhiko Yumikake, Tokyo, JP;
Kabushiki Kaisha Topcon, Tokyo, JP;
Abstract
Provided is an optical image measuring apparatus capable of effectively receiving interference light, particularly an alternating current component thereof using a smaller number of photo sensors. The optical image measuring apparatus includes a polarizing plate for converting a light beam from a broad-band light source to linearly polarized light, a half mirror for dividing the light beam into signal light and reference light, a piezoelectric element for vibrating a reference mirror, a wavelength plate for converting the reference light to circularly polarized light, a polarization beam splitter for extracting two different polarized light components from interference light produced from the signal light and the reference light which are superimposed on each other by the half mirror, CCDs for detecting the two different polarized light components, and a signal processing portion for producing an image of an object to be measured based on the detected polarized light components. A frequency for intensity modulation of the light beam is synchronized with a beat frequency of the interference light. A frequency of vibration of the reference mirror is synchronized with the beat frequency of the interference light and an amplitude of vibration thereof is set to be equal to or smaller than a wavelength of the interference light.