| 摘要 |
PURPOSE:To accurately inspect the direction of a wave length board in the optical head by a simple method regarding the method for inspecting the accurate assemblage of the wave length board while assembling the optical head used for reading information recorded on an optical magnetic disk medium. CONSTITUTION:This optical head is provided with the wave length board 8 for rotating the polarization angle of a signal light reflected by the optical magnetic disk medium and making it incident on a polarized light beam splitter 9 and when the direction of incorporating the wave length board 8 is inspected, a wave length board 15 is arranged between a light source 14 for issuing a straight line polarized light 16 and the wave length board 8 to be inspected. Or, by rotating the light source 14 for generating the straight line polarized light 16 around its light axis, a straight line polarized light 17 made incident on the wave length board 8 to be inspected is rotated by a specified angle beforehand and the generation of a big difference in the amount of light between the transmissive and reflective lights of the polarized light beam splitter 9. |
