公开(公告)号：US06100944A

公开(公告)日：2000-08-08

申请号：US948860

申请日：1997-10-10

申请人： Gary Sharp ,  Steven A. Serati ,  Teresa Kaye Ewing

发明人： Gary Sharp ,  Steven A. Serati ,  Teresa Kaye Ewing

IPC分类号： G02F1/1347 ,  G02F1/21 ,  G02F1/133

CPC分类号： G02F1/13473 ,  G02F1/21

摘要： The present invention provides a polarizing interferometer multiplex spectrometer using a zero-order switch, a multi-order switch and an output polarizer to multiplex the recovery of an entire input spectrum. The zero-order switch and multi-order switch require input light of a fixed polarization; thus the present invention provides a preferred embodiment that uses a zero-order switch and a multi-order switch positioned between an input polarizer and an output polarizer. For a sequence of time delays incremented by the multi-order and zero-order switches, the total transmitted power at all wavelengths is measured. From these, the coefficients of a Fourier series representation of the input spectrum are obtained, and the entire spectrum is mathematically reconstructed. Although the structure is similar to a tunable interference filter, the PIMS does not function as a filter, and more particularly, does not scan the transmission wavelength and measure power as a function of wavelength. The present invention further provides a multi-order switch that uses an active LC device to switch between summing and differencing the retardances of two fixed retarders. The present invention further provides a method of obtaining a Fourier series representation of a spectrum of input light.

摘要翻译： 本发明提供一种使用零级开关，多阶开关和输出偏振器的偏振干涉仪多路复用光谱仪来复用整个输入光谱的恢复。 零阶开关和多阶开关需要固定极化的输入光; 因此本发明提供了使用位于输入偏振器和输出偏振器之间的零级开关和多阶开关的优选实施例。 对于通过多阶和零阶开关递增的时间延迟序列，测量所有波长的总发射功率。 由此得到输入光谱的傅里叶级数表示的系数，并且对数据重构整个光谱。 虽然该结构类似于可调谐干涉滤波器，但是PIMS不用作滤波器，更具体地说，不扫描透射波长并且测量功率作为波长的函数。 本发明还提供了一种使用有源LC器件在两个固定延迟器的相加和差分减法之间切换的多阶开关。 本发明还提供一种获得输入光谱的傅里叶级数表示的方法。

公开(公告)号：US5574553A

公开(公告)日：1996-11-12

申请号：US363793

申请日：1994-12-27

申请人： Paul F. McManamon ,  Gary D. Sharp ,  Michael S. Salisbury ,  Steven A. Serati

发明人： Paul F. McManamon ,  Gary D. Sharp ,  Michael S. Salisbury ,  Steven A. Serati

IPC分类号： G01S7/491 ,  H04B10/148 ,  H04B10/158 ,  G01C3/08 ,  G01P3/36 ,  H04B10/00

CPC分类号： H04B10/64 ,  G01S7/4917 ,  H04B10/61 ,  H04B10/614

摘要： To greatly increase the sensitivity of a Heterodyne Ladar System, the receiver incorporates an optical preamplifier to amplify the ladar return signal prior to detection. This results in an increase in return signal power on the order of 25 dB. Spontaneous emission noise added by the fiber amplifier counters this gain in a normal scheme. The proposed receiver, however, incorporates a Polarization Optical Mixer to perform balanced mixing, thus rejecting added spontaneous emission beat noise terms and resulting in a large increase in system sensitivity.

摘要翻译： 为了大大增加Heterodyne Ladar系统的灵敏度，接收机包含一个光学前置放大器，用于在检测之前放大后退返回信号。 这导致25dB的信号功率增加。 由光纤放大器增加的自发辐射噪声以正常方案计数此增益。 然而，所提出的接收机包含偏振光混合器以进行平衡混合，从而拒绝添加的自发发射节拍噪声项，并导致系统灵敏度的大幅增加。

公开(公告)号：US5418380A

公开(公告)日：1995-05-23

申请号：US226461

申请日：1994-04-12

申请人： Darren M. Simon ,  Steven A. Serati

发明人： Darren M. Simon ,  Steven A. Serati

IPC分类号： G02B27/28 ,  G06E3/00 ,  G06K9/74 ,  G02B27/42

CPC分类号： G06K9/74 ,  G02B27/288 ,  G06E3/005

摘要： An optical correlator uses ferroelectric liquid crystal spatial light modulators (FLC-SLM's) in both the reference and filter planes. The SLM's include an electrically addressable memory to store images in the form a two-dimensional array of reflective pixels beneath the FLC layer. The SLM's selectively rotate the polarization of the light reflected by each pixel in accordance with the stored image. In particular, a laser produces a polarized beam that is directed through a first polarizing beamsplitter and onto the reference SLM. This beamsplitter blocks unmodulated light reflected by the reference SLM and transmits modulated light through a set of Fourier tranform lenses. The resulting beam is directed through a second polarizing beam splitter onto a filter SLM that has been programmed with the complex conjugate of the Fourier transform of a desired target image. Unmodulated light reflected from the filter SLM is blocked by the second polarizing beamsplitter and modulated light is reflected by the second polarizing beamsplitter through a set of inverse Fourier transform lenses. A CCD camera detects any correlation peak produced by the inverse Fourier transform lenses. A computer system downloads images to the SLM's and analyzes the correlation peaks detected by the camera. A half-wave plate can be included between both sets of SLM's and polarizing beamsplitters to allow manual adjustment of the polarization of the incident beam entering the SLM.

摘要翻译： 光学相关器在参考和滤波器平面中使用铁电液晶空间光调制器（FLC-SLM）。 SLM包括一个电可寻址存储器，用于以FLC层下面的反射像素的二维阵列的形式存储图像。 SLM根据存储的图像选择性地旋转由每个像素反射的光的偏振。 特别地，激光器产生被引导通过第一偏振分束器并且到参考SLM的偏振光束。 该分束器阻挡由参考SLM反射的未调制光，并通过一组傅立叶变换透镜传输调制光。 所得到的光束通过第二偏振分束器被引导到已经用期望目标图像的傅立叶变换的复共轭编程的滤波器SLM上。 从滤波器SLM反射的未调制光被第二偏振分束器阻挡，并且调制的光被第二偏振分束器通过一组傅立叶逆变换透镜反射。 CCD相机检测由傅里叶逆变换透镜产生的任何相关峰值。 计算机系统将图像下载到SLM并分析相机检测到的相关峰值。 两组SLM和偏振分束器之间可以包括半波片，以便手动调整进入SLM的入射光束的极化。