Patent EP0417709A2 successfully refreshed from Google Patents.
EP0417709A2
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EP
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Spectrum measuring equipment
Assignee: Advantest Corp
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Filing: 1990-09-10
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Granted: —
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Expires: 2010-09-10
Abstract
Abstract In spectrum measuring equipment the light to be measured is separated by a double-image polarizing element (12) into two polarized wave components whose planes of polarization perpendicularly cross each other and which have different optical axes, the two polarized wave components are applied to a dispersing element (14) so that their planes of polarization intersect the direction of light separation at ±45° thereto, respectively, and the sum of optical powers of the two polarized wave components separated by the dispersing element (14) is measured by a photodetector (16), whereby spectrum measurement not dependent on the polarization of the light to be measured can be achieved.
Inventors
- 👤 Masataka C/O Fujitsu Limited Shirasaki
- 👤 Hirochika C/O Fujitsu Limited Nakajima
- 👤 Yukimitsu C/O Advantest Corporation Watanabe
- 👤 Rinichiro C/O Advantest Corporation Yamamoto
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-08 03:37
CPC Classifications
G; G01; G01J; G01J3/00; G01J3/12; G01J3/18; G02; G02B; G02B27/00; G02B27/28; G02B27/283; G02B5/00; G02B5/30; G02B5/3083; G01J3/02; G01J3/0205; G01J3/0224
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
127 words
Spectrum measuring equipment comprising: a double-image polarizing element whereby light to be measured is separated to two polarized wave components which have their planes of polarization perpendicularly intersecting each other and have different optical axes; a dispersing element which is irradiated by said two polarized wave components from said double-image polarizing element so that the planes of polarization of said two polarized wave components cross the direction of light separation at an angle of ±45° thereto, respectively and whereby components of each wavelength contained in said two two polarized wave components are separated at the same angle of separation; and light-quantity measuring means for measuring the sum of the quantities of light of the two polarized wave components of the same wavelength separated by said dispersing element.
Claim 2
Dependent Claim
127 words
Spectrum measuring equipment comprising: a double-image polarizing element whereby light to be measured is separated to two polarized wave components which have their planes of polarization perpendicularly intersecting each other and have different optical axes; a dispersing element which is irradiated by said two polarized wave components from said double-image polarizing element so that the planes of polarization of said two polarized wave components cross the direction of light separation at an angle of ±45° thereto, respectively and whereby components of each wavelength contained in said two two polarized wave components are separated at the same angle of separation; and light-quantity measuring means for measuring the sum of the quantities of light of the two polarized wave components of the same wavelength separated by said dispersing element.
Claim 3
Dependent Claim
15 words
The spectrum measuring equipment of claim 1, wherein said dispersing element is a diffraction grating.
Claim 4
Dependent Claim
35 words
The spectrum measuring equipment of claim 1, further comprising collimator means whereby said two polarized wave components emitted from said double-image polarizing element are rendered respectively into parallel rays for incidence to said dispersing element.
Claim 5
Dependent Claim
19 words
The spectrum measuring equipment of claim 1, 2, or 3, wherein said double-image polarizing element is a Savart plate.
Claim 6
Dependent Claim
28 words
The spectrum measuring equipment of claim 1, further comprising collimator means for rendering said light to be measured into parallel rays for incidence to said double-image polarizing element.
Claim 7
Dependent Claim
20 words
The spectrum measuring equipment of claim 1, 2, or 5, wherein said double-image polarizing element is a double Wollaston prism.
Claim 8
Dependent Claim
39 words
The spectrum measuring equipment of claim 6, wherein said double Wollaston prism is composed of two Wollaston prisms disposed on the same optical axis with their directions of separation of polarized light held at right angles to each other.
Claim 9
Dependent Claim
34 words
The spectrum measuring equipment of claim 1, 2, 3, or 5, further comprising converging means which is irradiated by light waves separated by said dispersing element and converges them onto said light-quantity measuring means.
Claim 10
Dependent Claim
38 words
The spectrum measuring equipment of claim 1, wherein said light-quantity measuring means is a single photodetector which is irradiated by said two polarized wave components and outputs an electric signal corresponding to the sum of their optical powers.
Claim 11
Dependent Claim
75 words
The spectrum measuring equipment of claim 1, 2, 3, or 5, wherein said light-quantity measuring equipment includes a slit whereby separated light of said two polarized wave components from said dispersing element is selectively extracted with a width of a desired wavelength, the length of said slit being selected such that said polarized wave component thus extracted passes through the slit without being cut off in a direction perpendicular to said direction of light separation.
Claim 12
Dependent Claim
40 words
The spectrum measuring equipment of claim 1, 2, 3, or 5, wherein said double-image polarizing element is disposed so that said two polarized wave components are shifted from each other in a direction perpendicular to said direction of light separation.
References Cited (Backward Citations)
No citation records indexed.
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