| 摘要 |
PURPOSE:To read recording information by moving an element array or a recording medium successively in the array direction by a small pitch extent at every time, and photodetecting light by a photoelectric converting element array at each movement position and performing arithmetic processing. CONSTITUTION:Light from a light source 41 such as a laser or LED is passed through the slit-shaped aperture 42a of a light shield plate 42 to illuminate a card 23. This card 23 has a difference in reflection factor between a part where pits are formed in correspondence to recording information and a part where no pit is formed and part of light reflected by the card 23 which is irradiated in a slit shape is reflected by a half-mirror 45 to form an image on a photodiode array 22 through an image forming lens 46. When the image forming lens 46 is capable of magnifying, one pitch of recording information is expanded and pitch intervals of a photodiode array 22 need not be a natural multiple or integral multiple of recording information pitch invariably, which is utilized. Consequently, a read of extremely high density recording information is realized by the relatively simple structure.
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