Prism polarizer e.g. Glan-Thompson polarizer, for e.g. micro lithography-projection illumination system, has prisms, where birefringent characteristics of prisms are independent of stress-induced birefringence in wavelength area of light

摘要

The polarizer has a polarization divider unit attached between two prisms (2, 3), where the unit is provided for transmission of light in a polarization direction and for reflection of light in another polarization direction, where a plate (4) is used as the unit. The prisms are made of an optical uniaxial birefringent material that is synthetically manufactured. The birefringent characteristics of the prisms are independent of stress-induced birefringence in a wavelength area of the light. The material has a specified refractive index difference in the wavelength area.