BEAM SCANNER USING DEFLECTION DISK

摘要

PROBLEM TO BE SOLVED: To obtain a beam scanner using a diffraction deflection disk having an effect so that a high-density hologram pattern is formed by providing a deflection disk with hologram patterns formed on its upper and back surfaces and for diffracting a beam emitted from a light source. SOLUTION: The deflection disk 31 is fixed on the rotary shaft 32a of a driving motor 32 so as to be rotated, and the hologram patterns are formed on the upper and back surfaces of the disk 31. That is, a primary hologram pattern 33 for primarily diffracting the beam emitted from the light source 10 is formed on the back surface of the deflection disk 31, and a secondary hologram pattern 34 for diffracting the beam diffracted by the pattern 33 again is formed on the upper surface of the disk 31. Thus, the hologram patterns 33 and 34 are separately formed with low density. It is preferable that the hologram pattern 34 on the upper surface is formed so as to correct the bowing phenomenon of the beam diffracted by the hologram pattern 33 on the back surface.