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:
Jun. 16, 2009
Filed:
May. 10, 2005
Ryota Murakami, Koriyama, JP;
Yoshiharu Ooi, Koriyama, JP;
Ryota Murakami, Koriyama, JP;
Yoshiharu Ooi, Koriyama, JP;
Asahi Glass Company, Limited, Tokyo, JP;
Abstract
A double-wavelength light source unit capable of stable signal detection, is realized. The double-wavelength light source unit comprises a double-wavelength light source, a photodetector and a double-wavelength diffraction element, wherein the double-wavelength diffraction element comprises a diffraction grating which transmits a light beam of λand diffracts a light beam of λamong the light beams of wavelengths λand λ(λ≠λ) emitted from two laser diode diodes as the double-wavelength light source, a diffraction grating which diffracts a light beam of λand transmits a light beam of λ, a diffraction grating constituted by a grating-material forming a grating and a filler which transmits a light beam of λsince the refractive indices of both of these materials are equal at λand diffracts a light beam of λsince the refractive indices are different at λ, and a diffraction grating which transmits a light beam of λhaving a first polarization plane and diffracts a light beam of λhaving a polarization plane perpendicular to the first polarization plane.