Abstract: An optical distance measuring apparatus includes: a scanning element scanning a coherent irradiation light from a light source and sending it to an object under measurement; a photo detector receiving the irradiation light modulated by being passed through the object under measurement in accordance with the scanning, and performing photoelectric conversion on the irradiation light; and a measuring unit obtaining phase information of the object under measurement based on a signal photoelectrically converted by the photo detector and a signal to be a reference for the scanning by the scanning element, and obtaining a measurement value regarding the object under measurement based on the phase information.

Abstract: An optical distance measuring apparatus includes: a scanning element scanning a coherent irradiation light from a light source and sending it to an object under measurement; a photo detector receiving the irradiation light modulated by being passed through the object under measurement in accordance with the scanning, and performing photoelectric conversion on the irradiation light; and a measuring unit obtaining phase information of the object under measurement based on a signal photoelectrically converted by the photo detector and a signal to be a reference for the scanning by the scanning element, and obtaining a measurement value regarding the object under measurement based on the phase information.

Abstract: A spatial frequency reproducing apparatus includes a light source, a first means for modulating a light emitted from the light source into two lights having different frequencies and separately irradiated adjacently, a second means for two-dimensionally scanning the two lights, a third means for irradiating an object under measurement with the two lights, a fourth means for receiving and converting into an electrical signal at least two or more divided lights from the object under measurement with a boundary line being interposed therebetween in a direction substantially perpendicular to the direction separating the two lights, a fifth means for amplifying respective photoelectrically converted electrical signals while varying a degree of amplification according to frequencies thereof and generating a difference signal or a summation signal of the amplified signals, and a sixth means for obtaining a phase difference or an intensity difference of these signals to obtain a measurement value.

Abstract: A distance measurement system includes: an irradiating means for irradiating two coherent electromagnetic waves having frequencies different from each other to an object under measurement in a partially displacing manner while having a same area; an electromagnetic wave detecting means for detecting electromagnetic waves from at least two or more areas on the object under measurement with a boundary line being interposed therebetween to extend in a direction substantially perpendicular to the displacement direction; a signal generating means for generating a difference signal or a summation signal of respective outputs of the electromagnetic waves detected in the electromagnetic wave detecting means at symmetrical positions with respect to the boundary line; and a measuring means for obtaining a phase difference or intensity difference of the difference signal or summation signal to obtain measurement values.

Abstract: A spatial frequency reproducing apparatus includes a light source, a first means for modulating a light emitted from the light source into two lights having different frequencies and separately irradiated adjacently, a second means for two-dimensionally scanning the two lights, a third means for irradiating an object under measurement with the two lights, a fourth means for receiving and converting into an electrical signal at least two or more divided lights from the object under measurement with a boundary line being interposed therebetween in a direction substantially perpendicular to the direction separating the two lights, a fifth means for amplifying respective photoelectrically converted electrical signals while varying a degree of amplification according to frequencies thereof and generating a difference signal or a summation signal of the amplified signals, and a sixth means for obtaining a phase difference or an intensity difference of these signals to obtain a measurement value.