公开(公告)号：US07129491B2

公开(公告)日：2006-10-31

申请号：US10843899

申请日：2004-05-12

Applicant: Bradley Ferguson ,  Shaohong Wang ,  Xi-Cheng Zhang

Inventor： Bradley Ferguson ,  Shaohong Wang ,  Xi-Cheng Zhang

IPC: G01J5/02

CPC classification number: G01N21/3581 ,  G01N21/4795

Abstract: A method of obtaining a series of images of a three-dimensional object. The method includes the steps of transmitting pulsed terahertz (THz) radiation through the entire object from a plurality of angles, optically detecting changes in the transmitted THz radiation using pulsed laser radiation, and constructing a plurality of imaged slices of the three-dimensional object using the detected changes in the transmitted THz radiation. The THz radiation is transmitted through the object as a two-dimensional array of parallel rays. The optical detection is an array of detectors such as a CCD sensor.

Abstract translation: 一种获得三维物体的一系列图像的方法。 该方法包括以下步骤：从多个角度通过整个物体传输脉冲太赫兹（THz）辐射;使用脉冲激光辐射光学地检测所发射的太赫兹辐射的变化;以及使用以下步骤构建所述三维物体的多个成像切片 检测到的传输太赫兹辐射的变化。 太赫兹辐射通过物体作为平行光线的二维阵列传播。 光学检测是诸如CCD传感器的检测器阵列。

公开(公告)号：US20060214114A1

公开(公告)日：2006-09-28

申请号：US11086623

申请日：2005-03-22

Applicant: Kai Liu ,  Xi-Cheng Zhang ,  Jingzhou Xu

Inventor： Kai Liu ,  Xi-Cheng Zhang ,  Jingzhou Xu

IPC: G01N21/00

CPC classification number: G01J3/42 ,  G01N21/21 ,  G01N21/3581

Abstract: A broad bandwidth detector to measure intensity information of terahertz (THz) frequency pulses. The detector includes: coupling optics coupled to a coherent optical source; a GaSe substrate aligned such that the probe beam path intersects a first surface at a phase-matching angle; a polarization detector aligned in the probe beam path; and calculation means coupled to the polarization detector. The coupling optics direct the probe optical beam along a beam path that is substantially collinear with the pulse beam path of the THz frequency pulses. The polarization of the probe optical beam is varied based on interactions between the probe optical beam and the THz frequency pulses within the GaSe substrate. The polarization detector detects the varied polarization of the probe optical beam. The calculation means determine the intensity information of the THz frequency pulses based on the detected probe polarization of the probe optical beam.

Abstract translation: 用于测量太赫兹（THz）频率脉冲的强度信息的宽带宽检测器。 检测器包括：耦合到相干光源的耦合光学器件; GaSe衬底对准，使得探针光束路径以相位匹配角度与第一表面相交; 在探测光束路径中对准的偏振检测器; 以及耦合到偏振检测器的计算装置。 耦合光学器件沿着与THz频率脉冲的脉冲光束路径基本共线的光束路径来引导探测光束。 基于探针光束和GaSe衬底内的THz频率脉冲之间的相互作用，探针光束的极化发生变化。 偏振检测器检测探针光束的变化极化。 计算装置根据探测光束的检测探头偏振来确定THz频率脉冲的强度信息。

公开(公告)号：US07087902B2

公开(公告)日：2006-08-08

申请号：US10417597

申请日：2003-04-17

Applicant: Shaohong Wang ,  Xi-Cheng Zhang

Inventor： Shaohong Wang ,  Xi-Cheng Zhang

IPC: A61B6/00 ,  G01J5/02

CPC classification number: G01N21/3581 ,  G01N21/4795 ,  G02B27/2278

Abstract: Systems and methods for reconstructing a plurality of images of an object. An exemplary system includes a radiation source adapted to emit radiation at a plurality of frequencies; a lens with frequency-dependent focal length, such as a Fresnel lens, adapted to receive radiation modified by the object and to project onto a fixed image plane a frequency-dependent image of a slice of the object perpendicular to the radiation path; a sensor for capturing the frequency-dependent image of the object; and apparatus for facilitating creation and capture of a plurality of frequency-dependent images of the object at the plurality of frequencies. A system for reconstructing a tomographic image of the object further includes apparatus for assembling the plurality of frequency-dependent images to reconstruct the tomographic image. Methods and systems are described for use in the visible, audible, and THz frequency ranges and with broadband or narrowband radiation sources.

Abstract translation: 用于重建对象的多个图像的系统和方法。 示例性系统包括适于以多个频率发射辐射的辐射源; 具有频率相关焦距的透镜，例如菲涅尔透镜，适于接收由对象修改的辐射，并投射到固定的图像平面上，垂直于辐射路径的物体切片的频率相关图像; 用于捕获对象的频率相关图像的传感器; 以及用于促进在多个频率处创建和捕获对象的多个频率相关图像的装置。 用于重建物体的断层图像的系统还包括用于组装多个频率相关图像以重建断层图像的装置。 描述了用于可见光，听觉和THz频率范围以及宽带或窄带辐射源的方法和系统。

公开(公告)号：US20050253071A1

公开(公告)日：2005-11-17

申请号：US10843899

申请日：2004-05-12

Applicant: Bradley Ferguson ,  Shaohong Wang ,  Xi-Cheng Zhang

Inventor： Bradley Ferguson ,  Shaohong Wang ,  Xi-Cheng Zhang

IPC: G01J5/02 ,  G01N21/35 ,  G01N21/47

CPC classification number: G01N21/3581 ,  G01N21/4795

Abstract: A method of obtaining a series of images of a three-dimensional object. The method includes the steps of transmitting pulsed terahertz (THz) radiation through the entire object from a plurality of angles, optically detecting changes in the transmitted THz radiation using pulsed laser radiation, and constructing a plurality of imaged slices of the three-dimensional object using the detected changes in the transmitted THz radiation. The THz radiation is transmitted through the object as a two-dimensional array of parallel rays. The optical detection is an array of detectors such as a CCD sensor.

Abstract translation: 一种获得三维物体的一系列图像的方法。 该方法包括以下步骤：从多个角度通过整个物体传输脉冲太赫兹（THz）辐射;使用脉冲激光辐射光学地检测所发射的太赫兹辐射的变化;以及使用以下步骤构建所述三维物体的多个成像切片 检测到的传输太赫兹辐射的变化。 太赫兹辐射通过物体作为平行光线的二维阵列传播。 光学检测是诸如CCD传感器的检测器阵列。

公开(公告)号：US20050230625A1

公开(公告)日：2005-10-20

申请号：US10434329

申请日：2003-05-08

Applicant: Xi-Cheng Zhang ,  Jingzhou Xu ,  Tao Yuan

Inventor： Xi-Cheng Zhang ,  Jingzhou Xu ,  Tao Yuan

IPC: G01N21/35 ,  G02B21/00

CPC classification number: G01N21/3581 ,  G01N21/3563 ,  G02B21/00

Abstract: A microscope for producing an image of a target using THz radiation. The microscope comprises a source for providing an optical pump pulse and an optical probe pulse; a THz emitter for activation by pump pulse to emit a THz pulse that irradiates the target to form a target-modified THz pulse; a THz detector for modulating the probe pulse with the target-modified THz pulse to create a modulated optical probe pulse characteristic of the target; an optical detection system for modifying and detecting the modulated optical probe pulse and converting the modulated optical probe pulse to electronic information; and a processor for receiving the electronic information and producing an image of the sample using the electronic information. The THz emitter and detector comprise one or more EO crystals. The target is positioned on one of the EO crystals in a near-field of the THz pulse.

Abstract translation: 用于使用太赫兹辐射产生目标图像的显微镜。 显微镜包括用于提供光泵浦脉冲和光探针脉冲的源; 用于通过泵浦脉冲激活的THz发射器发射照射目标以形成目标修正的THz脉冲的THz脉冲; THz检测器，用于用目标修正的THz脉冲调制探针脉冲，以产生目标的调制光探针脉冲特性; 光学检测系统，用于修改和检测调制的光探针脉冲并将调制的光探针脉冲转换成电子信息; 以及处理器，用于接收电子信息并使用电子信息产生样本的图像。 太赫兹发射器和检测器包括一个或多个EO晶体。 目标位于太赫兹脉冲的近场中的一个EO晶体上。

公开(公告)号：US06844552B2

公开(公告)日：2005-01-18

申请号：US09826458

申请日：2001-04-05

Applicant: Xi-Cheng Zhang ,  Masahiko Tani ,  Zhiping Jiang ,  Qin Chen

Inventor： Xi-Cheng Zhang ,  Masahiko Tani ,  Zhiping Jiang ,  Qin Chen

IPC: G01N21/17 ,  G01J11/00 ,  G01N21/35 ,  G01J5/02

CPC classification number: G01N21/3581 ,  G01J11/00

Abstract: A system for emitting and detecting terahertz frequency electromagnetic pulses. The system comprises a single transceiver device, which may be an electro-optic crystal or photoconductive antenna, for both emitting and detecting the pulses. A related method comprises using a single transceiver device to both emit and detect electromagnetic terahertz frequency pulses. The transceiver device is excited by a pump pulse to emit a terahertz output pulse, which is modulated with a chopper. An object reflects the terahertz pulse and the reflected pulse is detected in the transceiver using a probe pulse. A lock-in amplifier set to the same frequency of the chopper is used to reduce noise in the signal detected by the transceiver. An image of the object may be created using the intensity or the timing of the peak amplitude of the terahertz pulses reflected from the object.

Abstract translation: 用于发射和检测太赫兹频率电磁脉冲的系统。 该系统包括单个收发器装置，其可以是电光晶体或光电导天线，用于发射和检测脉冲。 相关方法包括使用单个收发器装置来发射和检测电磁太赫兹频率脉冲。 收发器设备被泵浦脉冲激发以发射用斩波器调制的太赫兹输出脉冲。 一个对象反映了太赫兹脉冲，并且使用探针脉冲在收发器中检测到反射的脉冲。 设置为与斩波器相同频率的锁定放大器用于降低由收发器检测到的信号中的噪声。 可以使用从对象反射的太赫兹脉冲的峰值振幅的强度或定时来创建对象的图像。

公开(公告)号：US06690001B2

公开(公告)日：2004-02-10

申请号：US09826457

申请日：2001-04-05

Applicant: Zhiping Jiang ,  Xi-Cheng Zhang

Inventor： Zhiping Jiang ,  Xi-Cheng Zhang

IPC: H01J4014

CPC classification number: G04F13/026

Abstract: A method and apparatus for measuring electromagnetic pulses as a function of time. Radiation measurement, including measurement of single-shot, free-space terahertz femtosecond pulses, is realized using an electro-optical modulator in combination with an optical streak camera. This method and apparatus allow measurement of electromagnetic pulses previously unmeasurable due to the time resolution restrictions dictated by the time-frequency correlation.

Abstract translation: 一种用于测量电磁脉冲作为时间的函数的方法和装置。 使用电光调制器与光学条纹相机组合，实现了单次，自由空间太赫兹飞秒脉冲的测量。 该方法和装置允许测量由于时间 - 频率相关所规定的时间分辨率限制的先前不可测量的电磁脉冲。

公开(公告)号：US06556306B2

公开(公告)日：2003-04-29

申请号：US09754183

申请日：2001-01-04

Applicant: Zhiping Jiang ,  Ming Li ,  Xi-Cheng Zhang

Inventor： Zhiping Jiang ,  Ming Li ,  Xi-Cheng Zhang

IPC: G01B902

CPC classification number: G01N21/41 ,  G01N21/3563 ,  G01N21/3586

Abstract: A non-contact, free-space method for determining the index of refraction of a thin film at a desired angular frequency. The method includes generating an input desired-frequency pulse and an optically detectable probe pulse. The thin film is moved in and out of the path of the input pulse, creating an output pulse that alternates between a transmitted signal, created when the film intercepts the input pulse path, and a reference signal, created when the sample is outside the input pulse path. The output pulse modulates the probe pulse, which is then detected with a photo detector, and the difference between the transmitted signal and the reference signal is calculated. The above steps are repeated over a plurality of delay times between the input pulse and the probe pulse until a complete field waveform of the differential signal is characterized. The index of refraction is calculated as a function of a ratio between the differential signal for the thin film and the reference signal. A complete field waveform of the reference signal may be characterized by repeating the above steps for a reference plate identical to the sample except having a non-transmissive film instead of the thin, transmissive film.

公开(公告)号：US6111416A

公开(公告)日：2000-08-29

申请号：US920561

申请日：1997-08-29

Applicant: Xi-Cheng Zhang ,  Jenifer Ann Riordan ,  Feng-Guo Sun

Inventor： Xi-Cheng Zhang ,  Jenifer Ann Riordan ,  Feng-Guo Sun

IPC: G01R33/032 ,  G01J4/00 ,  G01N21/21 ,  G01N21/35 ,  G01R29/08 ,  G01R31/302 ,  G01R31/308

CPC classification number: G01R29/0885 ,  G01N21/3581 ,  G02F1/09 ,  G02F1/3515 ,  G02F1/353 ,  G02F2202/10 ,  G02F2202/101 ,  G02F2203/13

Abstract: Apparatus and methods for characterizing free-space electromagnetic energy, and in particular, apparatus/method suitable for real-time two-dimensional far-infrared imaging applications are presented. The sensing technique is based on a non-linear coupling between a low-frequency electric (or magnetic) field and a laser beam in an electro-optic (or magnetic-optic) crystal. In addition to a practical counter-propagating sensing technique, a co-linear approach is described which provides longer radiated field-optical beam interaction length, thereby making imaging applications practical.

Abstract translation: 提出了表征自由空间电磁能的装置和方法，特别是适用于实时二维远红外成像应用的装置/方法。 感测技术基于电光（或磁光）晶体中的低频电（或磁）场和激光束之间的非线性耦合。 除了实际的反向传播感测技术之外，描述了提供更长的辐射场 - 光束相互作用长度的共线方法，从而使成像应用成为可行的。

公开(公告)号：US08653462B2

公开(公告)日：2014-02-18

申请号：US13095267

申请日：2011-04-27

Applicant: Xi-Cheng Zhang ,  Jingle Liu

Inventor： Xi-Cheng Zhang ,  Jingle Liu

IPC: G01J5/02

CPC classification number: G01J1/58 ,  G01J3/4406

Abstract: Methods and systems for detecting radiation, particularly, terahertz (THz) radiation, are disclosed. The methods and systems disclosed include directing an optical beam in a volume of gas; ionizing at least a portion of the volume of gas with the optical beam to produce a plasma; and detecting a fluorescence produced from an interaction of a radiation wave with the plasma. The information contained in the characteristics of the detected fluorescence, for example, the amplitude and/or phase are used to characterize the radiation wave. Aspects of the invention may be used for homeland security, medicine, and astronomy, among other fields.

Abstract translation: 公开了用于检测辐射，特别是太赫兹（THz）辐射的方法和系统。 公开的方法和系统包括将光束引导到一定体积的气体中; 用光束电离至少一部分体积的气体以产生等离子体; 并且检测由辐射波与等离子体的相互作用产生的荧光。 包含在检测到的荧光特性中的信息，例如幅度和/或相位用于表征辐射波。 本发明的方面可用于国土安全，医药和天文学等领域。