| 摘要 |
PROBLEM TO BE SOLVED: To obtain the illuminate of 1000-12000 lumina by raising the illuminance of a display screen in a polarizer and a projection optical device using the polarlizer. SOLUTION: This projection optical device has a metal halide lamp 11, a polarization device 13, a light valve 15, an analyzer 16 are a projection lens 19 in the order of the progression of a light. The polarization device is the constitution in which a first polarizing element 20 being a reflection type and a second polarizing element 21 which has the constitution in which dye-contg. molecular are dispersed and which is an adsorption type are arranged so that transmission axes 22, 23 of them both coincide with the direction of an X axis. The first polarizing element 20 does not absorb a light and is hardly heated. A light to be absorbed by the second polarizing element 21 is limited to a Y-polarized light which is not completely reflected by the first polarizing element 20 to be remained and the polarizing element 21 is also hardly heated. The second polarizing element 21 is constituted so as to send out a polarized light having a high polarization degree. |
