| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a projection type display device capable of reducing speckle noise when using a light source having a coherency. <P>SOLUTION: In a projection type display device which displays an image by a light source having a coherency, a depolarization element which changes a polarization state of incident light is provided in a light path of light emitted from a light source such as a laser. The depolarization element comprises a plurality of unit areas in line, each of which has either a constitution composed of a plurality of areas which transmit light in mutually different polarization states or a constitution which transmits light in different polarization states successively, and thereby the speckle noise can be reduced regardless of a position to which an image is projected. <P>COPYRIGHT: (C)2012,JPO&INPIT |
