公开(公告)号：US08902948B2

公开(公告)日：2014-12-02

申请号：US13947910

申请日：2013-07-22

Applicant: Gigaphoton Inc.

Inventor： Shinji Nagai ,  Fumika Yoshida ,  Osamu Wakabayashi ,  Kouji Kakizaki

IPC: H01S3/22 ,  H01S3/23 ,  H01S3/10 ,  H01S3/00 ,  H01S3/225

CPC classification number: H01S3/10061 ,  H01S3/005 ,  H01S3/2251 ,  H01S3/2316

Abstract: A degree of polarization control device includes: a calcium fluoride crystal substrate for transmitting a laser beam; a polarization monitor for measuring the degree of polarization of a laser beam transmitted through the calcium fluoride crystal substrate; and a controller for controlling the rotation angle of the calcium fluoride crystal substrate according to the degree of polarization measured by the polarization monitor; the calcium fluoride crystal substrate being formed by a flat plate having a laser beam entering surface and a laser beam exiting surface running in parallel with the (111) crystal face, the Brewster angle being selected for the incident angle, the rotation angle around the [111] axis operating as a central axis being controlled by the controller.

公开(公告)号：US08855167B2

公开(公告)日：2014-10-07

申请号：US13931840

申请日：2013-06-29

Applicant: Gigaphoton Inc.

Inventor： Shinji Nagai ,  Fumika Yoshida ,  Osamu Wakabayashi ,  Kouji Kakizaki

IPC: H01S3/08 ,  G02B5/30 ,  G02B1/02 ,  H01S3/034 ,  H01S3/081 ,  H01S3/225

CPC classification number: H01S3/034 ,  G02B1/02 ,  G02B5/3091 ,  H01S3/0346 ,  H01S3/08054 ,  H01S3/0816 ,  H01S3/225 ,  H01S3/2251

Abstract: A gas discharge chamber that uses a calcium fluoride crystal which reduces a breakage due to mechanical stress (window holder and laser gas pressure), thermal stress from light absorption, and the like, increases the degree of linear polarization of output laser, and suppresses degradation due to strong ultraviolet (ArF, in particular) laser light irradiation. A first window (2) and a second window (3) of the gas discharge chamber have an incident plane and an emitting plane in parallel with a (111) crystal plane of their calcium fluoride crystal. With respect to an arrangement where laser light entering the calcium fluoride crystal passes through a plane including a axis and a axis of each of the first window (2) and the second window (3) as seen from inside the chamber (1), the first window (2) and the second window (3) are arranged in positions rotated in the same direction by the same angle about their axis.

Abstract translation: 使用减少由于机械应力（窗口保持器和激光气体压力）的破裂的氟化钙晶体，来自光吸收等的热应力的气体放电室增加了输出激光器的线性极化的程度，并抑制了劣化 由于强紫外线（特别是ArF）激光照射。 气体放电室的第一窗口（2）和第二窗口（3）具有与其氟化钙晶体的（111）晶面平行的入射面和发射平面。 关于进入氟化钙晶体的激光通过包括第一窗口（2）和第二窗口（3）中的每一个的<111>轴和<001>轴的平面的布置，从内侧看 室（1），第一窗口（2）和第二窗口（3）被布置在围绕其<111>轴线沿相同方向旋转相同角度的位置。