SYSTEMS AND METHODS FOR ISOLATING GAIN ELEMENTS IN LASER SYSTEMS

Methods and apparatus for protecting a seed laser in a laser-generated plasma (LPP) extreme ultraviolet (EUV) light system are disclosed. An isolation stage positioned on the optical path diverts light reflected from further components in the LPPEUV light system from reaching the seed laser. The isolation stage includes two AOMs separated by a delay line. The AOM directs light onto the optical path when opened and away from the optical path when closed. The delay introduced by the delay line is determined such that the opening and closing of the AOM can be timed to direct forward moving pulses onto the optical path and divert reflected light at other times. Isolation stages may be positioned between the gain elements to prevent amplified reflected light from reaching the seed laser and other potentially detrimental effects. 公开了用于保护激光产生等离子体(LPP)极紫外(EUV)光系统中的种子激光器的方法和设备。被定位在光路上的隔离级使从LPPEUV光系统中的进一步的部件反射的光转向，以免到达种子激光器。隔离级包括通过延迟线分离的两个AOM。AOM当打开时将光引导到光路上，并且当关闭时将光远离光路引导。由延迟线引入的延迟被确定为使得AOM的打开和关闭可以被定时以将前向移动的脉冲引导到光路上并且