-
公开(公告)号:EP0861426A1
公开(公告)日:1998-09-02
申请号:EP96938333.0
申请日:1996-11-11
CPC分类号: G01J5/06
摘要: An infrared optical system (100) incorporates a lens (118) imaging a remote scene onto a detector (112) within a cold shield (114). Stray radiation incident on the detector (112) is reduced by an optical stop in the form of a light emitting diode (LED) (126) producing negative luminescence. The LED (126) emits less radiation than background, and contributes less to the detector photon noise than an optical stop not exhibiting negative luminescence.
-
公开(公告)号:EP0880853A1
公开(公告)日:1998-12-02
申请号:EP96931886.0
申请日:1996-09-24
CPC分类号: H04N5/33 , G01J5/522 , H04N5/3651
摘要: A thermal imaging system (10) which is accoupled and operates by scanning recreates a thermal image by superimposing measured variations in infrared emission from a scene (22) onto a reference level supplied by a light emitting diode (28). The diode (28) is both a positive and negative luminescent emitter; emitted flux is current controlled to be equivalent to black body radiation at a range of temperatures which may be colder or hotter than ambient. A signal generated when the system (10) switches between scene and diode observation is a measure of the difference between the mean scene temperature and the diode effective temperature. In response to this digital, control means adjust the bias current through the diode (28) in order to reduce the temperature difference. The reference temperature converges towards the mean scene temperature as this process is repeated. Absolute temperature is thus restored and some image defects removed.
-
公开(公告)号:EP0852818A1
公开(公告)日:1998-07-15
申请号:EP96931903.0
申请日:1996-09-26
CPC分类号: H01L33/28
摘要: A dynamic infrared scene projector for use infrared detections systems which has particular, although not exclusive, use in thermal imaging or seeker systems. In such systems, a dynamic infrared scene projector is used to simulate the thermal scene for testing and calibration purposes. The device comprises an array of electroluminescent semiconductor diode structures, capable of emitting both positive and negative luminescence, and electronic circuitry for supplying currents of both polarity to each diode independently so that the emission of positive and negative luminescence can be controlled. The diode structures in the array are based on narrow bandegap semiconductor materials, for example, the Hg1-xCdxTe, In1-xAlxSb, Hg1-xZnxTe or In1-xTlxSb materials systems (where x is the composition). In a preferred embodiment, the diodes are capable of emitting infrared radiation in the wavelength regions between 3-5 νm or 8-13 νm. By utilizing the negative luminescence properties of the diode structures, the dynamic infrared scene projector can simulate a wide range of temperatures, and in particular low temperatures, without external cryogenic cooling. The dynamic infrared scene projector also permits the use of faster thermal imager frame rates than are achievable with existing systems.
-
公开(公告)号:EP1034568A1
公开(公告)日:2000-09-13
申请号:EP98928446.8
申请日:1998-06-10
发明人: ASHLEY, Timothy , DEAN, Anthony, Brian , ELLIOTT, Charles, Thomas , PHILLIPS, Timothy, Jonathan
IPC分类号: H01L29/78 , H01L29/10 , H01L29/205
CPC分类号: H01L29/66522 , H01L29/1033 , H01L29/105 , H01L29/1079 , H01L29/205
摘要: A field effect transistor (FET) is of the type which employs base biasing to depress the intrinsic contribution to conduction and reduce leakage current. It incorporates four successive layers (102 to 108): a p+ InSb base layer (102), a p+ InAlSb barrier layer (104), a π intrinsic layer (106) and an insulating SiO¿2? layer (108); p?+¿ source and drain regions (110, 112) are implanted in the intrinsic layer (106). The FET is an enhancement mode MISFET (100) in which biasing establishes the FET channel in the intrinsic layer (106). The insulating layer (108) has a substantially flat surface supporting a gate contact (116). This avoids or reduces departures from channel straightness caused by intrusion of a gate groove, and enables a high value of current gain cut-off frequency to be obtained. In FETs with layers that are not flat, departures from channel straightness should not be more than 50 nm in extent, preferably less than 5 nm.
摘要翻译: 场效应晶体管(FET)属于采用基极偏置来降低对传导的固有贡献并降低漏电流的类型。 它包含四个连续的层(102到108):p + InSb基极层(102),p + InAlSb势垒层(104),π本征层(106)和绝缘SiO 2层 层(108); 源极和漏极区(110,112)被注入到本征层(106)中。 FET是增强型MISFET(100),其中偏置在本征层(106)中建立FET沟道。 绝缘层(108)具有支撑栅极触点(116)的基本上平坦的表面。 这避免或减少了由于沟槽侵入引起的沟道平直度的偏离,并且能够获得高电流增益截止频率值。 在层不平坦的FET中,偏离通道直线度的范围不应超过50nm,优选小于5nm。
-
公开(公告)号:EP0861426B1
公开(公告)日:2001-08-29
申请号:EP96938333.0
申请日:1996-11-11
IPC分类号: G01J5/06
CPC分类号: G01J5/06
摘要: An infrared optical system (100) incorporates a lens (118) imaging a remote scene onto a detector (112) within a cold shield (114). Stray radiation incident on the detector (112) is reduced by an optical stop in the form of a light emitting diode (LED) (126) producing negative luminescence. The LED (126) emits less radiation than background, and contributes less to the detector photon noise than an optical stop not exhibiting negative luminescence.
-
6.
公开(公告)号:EP0842581A1
公开(公告)日:1998-05-20
申请号:EP96925850.0
申请日:1996-07-29
CPC分类号: H04N5/3651 , F41G7/001 , F41G7/2253 , F41G7/2293 , H04N5/33
摘要: A thermal sensing system (10) including an array of photon detectors (14) produces a detector-dependent response to irradiation. Variations in individual detector characteristics produce a fixed pattern noise which degrades an image or other response. A switchable mirror (M1) may at one position (Pcal) direct infrared radiation from a light emitting diode (20) onto the detector array (14). The diode (20) is both a negative and positive luminescent emitter; the flux emitted is current controlled to be equivalent to black body radiation at a range of temperatures both colder and hotter than ambient. Calibration relationships comprising transfer functions relating incident intensity to signal response are derived for each detector. Alternatively the mirror (M1) may be at an observation position (Pobs) and infrared radiation from a remote scene reaches the detector array (14). Resulting detector signals are converted into corrected fluxes using individual calibration relationships previously derived and an image or response with reduced fixed pattern noise is obtained.
-
公开(公告)号:EP0401352A1
公开(公告)日:1990-12-12
申请号:EP90900935.0
申请日:1989-11-24
IPC分类号: H01L31
CPC分类号: H01L31/111 , H01L31/02327 , H01L31/02966 , H01L31/101
摘要: Un photodétecteur (10) du type non équilibré comporte trois parties (14, 16, 18) disposées de manière successive en couches. Chacune des parties (par exemple 14) contient trois couches (14A, 14B, 14C) de matériaux semiconducteurs du système d'alliage (CMT) CdxHg1-xTe. La couche centrale (14B) de chaque partie (14) a une largeur de bande interdite CMT étroite, c'est-à-dire x = 0,19 ou 0,265 permettant une absorption de 3 à 5 mum) ou 8 à 12 mum, et présente un dopage très faible (1015 cm-3) assurant une conductivité intrinsèque. Elle a une épaisseur de 1,5 mum, moins d'un tiers d'une longueur d'absorption optique. Les couches extérieures de chaque partie (14A, 14B) ont une épaisseur de 10 mum et ont une largeur de bande interdite CMT large, c'est-à-dire x = 0,4. Elles ont des concentrations dopantes de type n et p de 3x1016 cm-3 assurant une conductivité intrinsèque. Chaque couche centrale (14B) est par conséquent liée par un contact de rejet (14AB) ainsi que par un contact d'extraction (14BC), abaissant sa concentration de support à un niveau extrinsèque sous l'effetd'une polarisation électrique. Cette configuration stimule le refroidissement à basse température. Les couches centrales (14B à 18B) ont une épaisseur collective (4,5 mum approchant une longueur d'absorption optique (6 mum). Un miroir (20) est agencé pour tourner du fait du rayonnement du photodétecteur (10) qu'il transmet. Cette configuration présente une épaisseur de région active totale égale à six fois celle d'une région centrale individuelle (14B), et supérieure à une longueur d'absorption optique. Il en résulte que ledit photodétecteur (10) présente un rendement quantique élevé, malgré les problèmes que pose le matériau CMT de type n en ce domaine.
摘要翻译: PCT No.PCT / GB89 / 01406 Sec。 371日期1990年8月23日 102(e)日期1990年8月23日PCT提交1989年11月24日PCT公布。 公开号WO90 / 06597 日期:1990年6月14日。非平衡类型的光电检测器(10)包含相似层结构的三个连续设置的部分(14,16,18)。 每个部分(例如14)包含CdxHg1-xTe合金系统(CMT)的半导体材料的三层(14A,14B,14C)。 每个部分(14)的中心层(14B)具有窄带隙CMT,即在3-5μm或8-12μm的吸收为x = 0.19或0.265,并且具有非常低的掺杂(1015cm-3) 提供内在的电导率。 厚度为1.5μm,小于光吸收长度的三分之一。 每个部分(14A,14B)的外层是10μm厚,并且具有宽带隙CMT,即x = 0.4。 它们具有各自的n和p型掺杂剂浓度为3×10 16 cm -3,提供外在电导率。 因此,每个中心层(14B)由排斥接触(14AB)和提取接触(14BC)限制,其在电偏压的作用下将其载流子浓度降低到外在水平。 这将模拟冷却至低温。 中心层(14B至18B)具有接近光学吸收长度(6μm)的总体厚度(4.5μm)。 反射镜(20)布置成通过光电检测器(10)返回由其传输的辐射。 这呈现出单个中心区域(14B)的六倍的总有源区厚度并且大于光吸收长度。 因此,尽管在这方面存在n型CMT材料的缺陷,但是光电检测器(10)因此具有高的量子效率。
-
-
-
-
-
-