Patent ID: 8472019

Claim:
A spectroscopic characteristics acquisition unit, comprising: a light emitting unit to emit light to illuminate a measurement target; a lens array including a plurality of lenses arranged in one direction to receive a portion of reflected light reflected from the measurement target; a light blocking member having a pinhole array therein comprising a plurality of openings arranged in one direction, light coming from the lens array passing through the plurality of openings; a focusing unit to focus light coming from the pinhole array as an image at a given position; a diffraction unit to diffract the light to different directions depending on wavelength of light received by the focusing unit; and a light receiving unit to receive the reflected light diffracted by the diffraction unit, the light receiving unit being positioned at a position where the focusing unit focuses an image, the light receiving unit including a spectroscopic sensor array having a plurality of spectroscopy sensors arranged in one direction, each of the spectroscopy sensors including a given number of pixels arranged in one direction, each pixel being sensitive to different light having different spectral characteristics, each of the lenses constituting the lens array corresponding to one of the openings of the pinhole array, the numerical aperture NA of the lens in the arrangement direction of the lenses in the lens array satisfying the formula NA>sin(θmax) with respect to the maximum angle of view θmax of the focusing unit.