公开(公告)号：US20010030745A1

公开(公告)日：2001-10-18

申请号：US09753673

申请日：2001-01-04

Applicant: EXFO Electro-Optical Engineering Inc.

Inventor： Gang He ,  Daniel Gariepy ,  Gregory Walter Schinn

IPC: G01J003/28

CPC classification number: G01J3/447 ,  G01J3/12

Abstract: An optical spectrum analyzer comprises a diffraction grating (DG), a polarization decomposing unit (PDM) for decomposing the input light beam into first and second light beams having mutually-perpendicular linear states of polarization, and two output ports (FP2/1, FP2/2) each for receiving from the grating, substantially exclusively, a respective one of the polarized light beams (LT, LR) after diffraction by the diffraction grating (DG). Each of the linearly-polarized light beams is directed onto the diffraction grating with its linear state of polarization at any prescribed angle to a corresponding plane of diffraction of the diffraction grating The arrangement is such that the state of polarization of the light beams, at any particular wavelength within an operating band of the analyzer remains substantially unchanged with respect to time, The analyzer also may have a reflector (RAM) for reflecting the light beams leaving the diffraction grating after diffraction a first time so as to return them to the diffraction grating for diffraction a second time.

Abstract translation: 光谱分析仪包括衍射光栅（DG），用于将输入光束分解成具有相互垂直的极化状态的第一和第二光束的偏振分解单元（PDM）和两个输出端口（FP2 / 1，FP2 / 2），每个用于在衍射光栅（DG）衍射之后从光栅接收基本上仅相应的一个偏振光束（LT，LR）。 每个线性偏振光束以与其衍射光栅的相应衍射平面成任意规定角度的线性极化状态被引导到衍射光栅上。这种布置使得光束的偏振状态 分析仪的工作频带内的特定波长相对于时间保持基本不变。分析仪还可以具有用于在衍射之后第一次反射离开衍射光栅的光束的反射器（RAM），以便将它们返回到衍射光栅 用于衍射第二次。