| 摘要 |
PROBLEM TO BE SOLVED: To obtain a two-dimensional array-type confocal optical apparatus by which the influence of adjacent beams is reduced without increasing the ratio of a spot diameter to a spot pitch by a method wherein illumination light radiated from a pinhole is changed so as to have mutually rectangular planes of polarization and reflected light from an object is transmitted selectively in such a way that the planes of polarization are at right angles between pinholes. SOLUTION: Illumination light which is changed into linearly polarized light by an optical- path branching optical element 5 is condensed by a microlens array part 6, it is passed through a pinhole which corresponds to a pinhole array part 7, and it is incident on a liquid-crystal cell 20. The illumination light is changed into linearly polarized light whose planes of polarization are different by 90 deg. according to whether a transparent electrode exist inside a cell 20 or not, and the illumination light from adjacent pinholes has rectangular planes of polarization. The illumination light which is radiated from the cell 20 is changed into circularly polarized light by a 1/4 phase difference plate 10, a phase jump at 180 deg. is generated when the light is reflected by an object A, and reflected light is passed through the phase difference plate 10 so as to be polarized at 90 deg. with reference to the illumination light. The reflected light inside the cell 20 is rotated and polarized by 90 deg. by using the pattern of the transparent electrode so as to be passed through the pinhole. |
