| 摘要 |
<p>PURPOSE:To obtain a hologram scanner which is small-sized and oscillates less by providing a mechanism for generating a rotating magnetic field around a holo top and making common use of the holo top itself as a shaft and a rotor. CONSTITUTION:The scanner is constituted of the holo top 20, electromagnets 26 and a sensor 27. The outside circumferential member 24 of the holo top 20 is formed of a magnetic material. The holo top is freely rotatably supported by means of a bearing 25. Holograms 21, 22 are mounted to the lower two surfaces thereof and a transmission type Fresnel lens 23 is provided to the inside. Plural pieces of the electromagnets 26 are disposed equidistantly to the outside circumference of the top 20 in promixity thereto so that the rotating magnetic field is generated when electric current is supplied thereto. The sensor 27 is provided at the focusing point of the reimaging light on the central axis of rotation of the top 20. The top 20 is rationally driven by the rotating magnetic field generated when the electric current is supplied to the electromagnets 26. The reimaging light 28 incident on the holograms 21, 22 is condensed by the holograms 21, 22 and the lens 23 and is read by the sensor 27.</p> |
