| 摘要 |
PROBLEM TO BE SOLVED: To provide a displacement gauge for optically measuring a displacement amount of an object to be measured, capable of reducing an output variation caused by output fluctuation in a light source or fluctuation in ambient temperature for stable and reliable measurement values, and capable of coping with various resolutions with single sensor (displacement gauge). SOLUTION: A single polarized light from an LED 1 which is a light source is projected to an object 4, which is to be measured, through a PBS (polarizing beam splitter) 2. The projected light is reflected on the surface of the object 4, which is guided into the PBS 3. Each polarized light having been split there into P wave and S wave is inputted in a PD (photodiode) 5 and a PD 6, respectively, as detection light. The outputs of the PDs 5 and 6 are inputted in a calculation circuit 14 through amplifiers 11 and 12, where the displacement amount of the object 4 is calculated and outputted. The light quantity of the LED 1 is controlled by a light source control circuit 15, and the position of the PD 5 is variably controlled in an arrow direction. COPYRIGHT: (C)2004,JPO
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