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. 13, 2000
Filed:
Mar. 23, 1999
Shigenori Nagano, Tokyo, JP;
Makoto Fujino, Tokyo, JP;
Akira Takada, Tokyo, JP;
Nobuo Hori, Tokyo, JP;
Kabushiki Kaisha Topcon, Tokyo, JP;
Abstract
Provided is a signal formation apparatus for use in an interference measurement which is capable of achieving a simplicity of optical adjustments and a subminiature of the apparatus, as well as a reduction of an influence by a wavelength variation of a laser light to the utmost. A coherent light emitted from a light source section 1 is supplied to a light emission portion 3 via a connection section 2. The light emission portion 3 comprises a straight type incidence waveguide 32, a dividing waveguide 33, emission waveguides 34 and 35, and a phase modulation section 36, which are provided on an optical substrate 31. The light emission portion 3 performs a phase modulation for one of luminous fluxes and emits irradiation luminous fluxes while keeping the other luminous flux as it is. In an irradiation optical portion 4, these irradiation luminous fluxes are collimating and deflected, and irradiated onto a measurement spot of a scale section 5. In the scale section 5, the two luminous fluxes are diffracted into approximately the same direction and incident onto a light receiving portion 6. A light receiving portion 7 convert the received luminous flux to an electrical received signal, and a displacement of the scale section 5 can be obtained by a displacement measurement section 8, based on the received signal.