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:
Jan. 29, 2013
Filed:
Mar. 03, 2010
Yoshiyuki Kuramoto, Utsunomiya, JP;
Yoshiyuki Kuramoto, Utsunomiya, JP;
Canon Kabushiki Kaisha, , JP;
Abstract
An optical interference measuring apparatus comprises a first multiple-wavelength light sourceemitting a light beam having a plurality of spectra, a second multiple-wavelength light sourceemitting a light beam having a wavelength different from that of the light beam from the first multiple-wavelength light source, a polarizing beam splitterseparating the light beams, a reference surfacereflecting the light beam from the second multiple-wavelength light source, a test surfacereflecting the light beam from the first multiple-wavelength light source, spectral optical elementsdividing interference signals of the light beams, detecting deviceswhich detect interference signals having single wavelengths of the light beams for a plurality of frequencies, and an analyzerprocessing the signals from the detecting devicesto calculate an optical path difference between the reference surfaceand the test surface