Title:
OPTICAL MEASUREMENT DEVICE
Document Type and Number:
WIPO Patent Application WO/2024/075266
Kind Code:
A1
Abstract:
This optical measurement device comprises: a wavelength sweeping light source (1) that outputs sweep light, the wavelength of which continuously changes over time; an irradiation optical system (3) that emits, as measurement light, output light for measurement generated by the sweep light from the wavelength sweeping light source (1) into a space toward an object (8) to be measured, and that receives reflected light, which is generated when the object (8) to be measured reflects the measurement light, and outputs the reflected light as measurement reflected light; a circulating optical path (4) that has a loop part and that is configured so that reference output light generated by the sweep light from the wavelength sweeping light source (1) circulates through the loop part N (an integer of 0 or more) times, and circulating reference light is output during every circulation; a measurement signal acquisition unit (5) that multiplexes the measurement reflected light from the irradiation optical system (3) and the circulating reference light from the circulating optical path (4), and that outputs a precise measurement signal obtained by photoelectrically converting a multiplexed interference light, and outputs, on the basis of the sweep light, a plurality of rough measurement signals consisting of electrical signals obtained using a plurality of circulation number measurement light beams having different refraction index dependencies with respect to an optical path; and a signal processing unit (7) that obtains, by means of the precise measurement signal from the measurement signal acquisition unit (5), an optical path length difference between the measurement reflected light and the circulating reference light, and that obtains, by means of the plurality of rough measurement signals from the measurement signal acquisition unit (5), an optical path length difference between the measurement reflected light and the circulating reference light, so as to identify the number of circulations of the circulating reference light in the circulating optical path (4).
Inventors:
YAMAUCHI TAKANORI (JP)
KOTAKE NOBUKI (JP)
GOTO HIROKI (JP)
IMAKI MASAHARU (JP)
SONO NAOKI (JP)
KOTAKE NOBUKI (JP)
GOTO HIROKI (JP)
IMAKI MASAHARU (JP)
SONO NAOKI (JP)
Application Number:
PCT/JP2022/037544
Publication Date:
April 11, 2024
Filing Date:
October 07, 2022
Export Citation:
Assignee:
MITSUBISHI ELECTRIC CORP (JP)
International Classes:
G01C3/06; G01B9/02004; G01B11/00; G01N21/17; G01S17/34
Attorney, Agent or Firm:
SANNO PATENT ATTORNEYS OFFICE (JP)
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