摘要 |
<P>PROBLEM TO BE SOLVED: To restrict speckle of an illuminating device using coherent light source. <P>SOLUTION: Laser beam L50 generated by a laser light source 50 is reflected by a light beam scanner device 60 to be radiated on a hologram recording medium 45. On the hologram recording medium 45, an image 35 of a scattering plate is recorded as a hologram using reference light focused on scanning reference point B. The optical beam scanner device 60 refracts the laser beam L50 at the scanning reference point B to be radiated on the hologram recording medium 45. At this moment, refraction state of the laser beam is changed in time so as to perform scanning such that a radiation position of the refracted laser beam L60 with respect to the hologram recording medium 45 is changed in time. Regardless of the radiation position of the beam, diffraction light L45 from the hologram recording medium 45 reconstructs the image 35 of the same linear scattering plate at the same position. On a light receiving surface R of an object 70 to be illuminated, an illumination spot is formed in which speckle is restricted by the reconstructed image 35 of the hologram. <P>COPYRIGHT: (C)2012,JPO&INPIT |