| 摘要 |
PURPOSE:To obtain high energy efficiency and to make a device compact by compensating wavelength dispersion generated among acoustooptic elements of a composite system by a dispersion optical system. CONSTITUTION:The wavelength dispersion generated between an acoustooptic modulator 3 and an acoustooptic deflector 6 is compensated as the whole composite system by one dispersion optical system by arranging a prism 5 between both, and placing the acoustooptic modulator 3 and prism 5 in conjugate relation by an incidence-side relay lens system 41 and the acoustooptic deflector 5 and prism 5 in conjugate relation by a projection-side relay lens system 42. Then the wavelength dispersion of the acoustooptic elements is compensated as the composite system by the dispersion optical system, so the number of dispersion optical members for compensation can be decreased. Consequently, the number of components of the optical system is decreased and the optical path lens is also shortened, so the energy loss of the optical system is reduced and the whole optical system can be made compact. |
