| 摘要 |
PURPOSE:To improve condensing efficiency by installing an optical element which has the characteristics of diffusing light only in the direction of diffraction grating slits between an incident slit and a condenser mirror. CONSTITUTION:Between an incident slit 3 and a condenser mirror 5, a cylindrical lens 9 to enlarge a focus in the vertical direction without affecting a horizontal spectrum focal plane is inserted. By so doing, focusing points in the horizontal direction and the vertical direction can be approached with each other, condensing density can be increased and monochromatic light of high light intensity can be obtained. By changing the focal length of the cylindrical lens 9, the spectrum focal plane in the vertical direction after correction can be moved. |
