REFRACTION OPTICAL SYSTEM USING A POLARIZATION EFFECT REMOVING PANEL

摘要

PURPOSE: A refraction optical system is capable of easily producing a needed wavelength by use of a polarization effect removing panel without affecting a pattern formation instead of 1/4 wavelength panel or 1/2 wavelength panel. CONSTITUTION: The refraction optical system comprises: a reticle(1) having a pattern to be illuminated; a first lens(2) for correcting a difference between rays of light through the reticle; a first rectangular prism(5) for receiving the corrected ray of light by the first lens; a dielectric multi thin film layer(6) for refracting a S-waveform and passing a P-waveform, wherein the dielectric multi thin film layer is comprised of a high refraction material and a low refraction material deposited in turn; a 1/4 wavelength panel(4) for receiving the S-waveform refracted by the dielectric multi thin film layer, producing a phase difference between a normal ray of light and an abnormal ray of light, and changing the S-waveform to a circular polarized light, wherein the 1/4 wavelength panel produces a phase difference between a normal ray of light of the polarized light and an abnormal ray of light thereof, and then changes the polarized light to the P-waveform; a reflector(3) for refracting the polarized light through the 1/4 wavelength panel to re-receiving the light thus refracted to the 1/4 wavelength panel; a second rectangular prism(7) for receiving the P-waveform to the first rectangular prism and the dielectric multi thin film layer; a second lens(8) for receiving the P-waveform through the second rectangular prism; and a polarization effect removing panel(9) for making the polarization of light through the second lens irregular, and for illuminating the light to the wafer.