High resolution etalon - grating monochromator spectroscope

摘要

High resolution etalon - lattice type spectroscope or it is the monochromator. It is very useful in band width measurement of the narrow band excimer laser to which desirable execution form gives the slit function where the ultraviolet range is very narrow, is used for integrated circuit flat printing method. The light where light from the laser comes out of the combination burning and diffuser in the diffuser and spreads irradiates the etalon. Portion of the light which comes out of the etalon, is gathered in the slit which is arranged with stripe pattern of the etalon and is led. The light which passes the slit is parallel converted, the lattice which is almost arranged with Littrow which the light which the said parallel is converted, follows to wave length and makes light disperse constitution is irradiated. Portion of the light which displays the wave length which corresponds to the etalon stripe which is selected and is dispersed, passes the 2nd slit, monitoring is done by the photodetector. When being adjusted the wave length where the etalon and the lattice are the same accurate, slit function, approximately 0.034pm (FWHM) and approximately 0.091pm (95 percent integral calculus) the way is decided as very narrow ones. The etalon and the lattice are accommodated in the container which does not have a leak to which the gas like nitrogen or helium is filled. At the time of constituting the spectroscope, wave length scan of the spectroscope is done by changing the gas pressure inside the container which is in the midst of scanning. At the time of monochromator constituting, band width of the laser beam leads portion of the laser beam in the monochromator, it is possible to measure very accurately by scanning the laser wave length which covers the range which includes monochromator slit wave length.