Patent ID: 6394606
Filing Date: 2002-05-28
Classification: G02B,H04N

Abstract:
A projection-type display device, comprising:a reflection-type image-forming means for spatially modulating illumination light of a predetermined plane polarization to emit an optical image with a plane polarization rotated with respect to the plane polarization of the illumination light, a projection optical system for projecting said optical image, a light source for emitting said illumination light, and a polarization beam splitter for emitting said illumination light emitted from said light source toward said reflection-type image-forming means and emitting a predetermined polarization component in the optical light incident from said reflection-type image-forming means to said projection optical system, said polarization beam splitter being formed by a member satisfying the following relationship: 5.00Ã—102&GreaterEqual;K&CenterDot;Î±&CenterDot;E&CenterDot;CpÏ &it;&Integral;Î»2Î»1&it;(1-T)&it;&dd;Î»where,K: photoelasticity constant of said member (nm/mmÂ·mm2/N), &agr;: linear expansion coefficient of said member (10âˆ’6/K), E: Young's modulus of said member (103N/mm2), &lgr;: wavelength of the illumination light (nm), T: internal transmittance of said member at the wavelength &lgr;, &rgr;: specific gravity of said member (g/cm3), and Cp: specific heat of said member (J/gÂ·k), the integration range in Equation being a range of the light absorption wavelength band of the member.