公开(公告)号：WO1991013323A1

公开(公告)日：1991-09-05

申请号：PCT/US1991000866

申请日：1991-02-11

Applicant: HUGHES AIRCRAFT COMPANY

Inventor： HUGHES AIRCRAFT COMPANY ,  VALI, Victor ,  CHANG, David, B. ,  BROWNRIGG, Patrick, C.

IPC: G01F23/28

公开(公告)号：WO1993007530A1

公开(公告)日：1993-04-15

申请号：PCT/US1992007168

申请日：1992-08-27

Applicant: HUGHES AIRCRAFT COMPANY

Inventor： HUGHES AIRCRAFT COMPANY ,  LAWRENCE, Albert, F. ,  VALI, Victor ,  CHANG, David, B. ,  LANDIS, Gary

IPC: G02F01/295

CPC classification number: G02F1/2955 ,  G01S7/48 ,  G02F1/0134 ,  G02F1/035 ,  G02F2202/20 ,  G02F2203/24 ,  H01S5/40

Abstract: Optical phased arrays employing a large number of light emitters and optical phase delays between adjacent emitters to steer and focus on optical beam from the contributions of all the light emitters. The array can include a laser oscillator (22) as the light source, with the laser light being conducted via optical waveguides (26, 30 and 32) into optical fibers (34), with phase delays being effected by piezoelectric or electro-optic effects on the optical waveguides. The array can be used in a low cost display device for generating optical images or in an optical memory.

公开(公告)号：WO1993017472A1

公开(公告)日：1993-09-02

申请号：PCT/US1993001152

申请日：1993-02-08

Applicant: HUGHES AIRCRAFT COMPANY

Inventor： HUGHES AIRCRAFT COMPANY ,  CHANG, David, B. ,  VALI, Victor

IPC: H01S03/00

CPC classification number: H01S3/0057 ,  G02F1/0134 ,  G02F1/035 ,  G02F2203/26

Abstract: This invention discloses a method and apparatus for shortening the length of a pulse of light. Generally, the method entails altering the index of refraction of an optical medium (14) through which the pulse of light is traveling at an area of the medium (14) where the front end of the pulse of light is located, such that the front end of the pulse of light travels slower than the back end, thus enabling the back end to catch up with the front end in order to shorten the length of the pulse. To accomplish this, it is proposed to generate an electric field across the optical medium (14) by a charge carrying medium (12) positioned relative to the optical medium (14), such that the index of refraction is altered by the electro-optic effect. In addition, it is possible to alter the index of refraction of the optical medium (14) by surrounding the optical medium (14) with a piezoelectric material (20) and applying an electric field to the piezoelectric material (20) such that the piezoelectric material (20) compresses the optical medium (14), thus altering the index of refraction.

公开(公告)号：WO1993014438A1

公开(公告)日：1993-07-22

申请号：PCT/US1993000144

申请日：1993-01-08

Applicant: HUGHES AIRCRAFT COMPANY

Inventor： HUGHES AIRCRAFT COMPANY ,  VALI, Victor ,  CHANG, David, B. ,  SHIH, I-Fu ,  YOUMANS, Bruce, R.

IPC: G02F01/29

CPC classification number: G02F1/29 ,  G02F1/03 ,  G02F1/0305 ,  G02F1/292 ,  G02F2201/12 ,  G02F2202/20 ,  G02F2203/18 ,  G02F2203/24 ,  G02F2203/28

Abstract: An adaptive electrooptical lens system for use in optical data storage systems, optical phased arrays, laser or other optical projectors, and raster scanning devices, and the like. The invention provides an electrooptical means for scanning an optical beam or moving an optical storage or retrieval point. Beam movement is achieved electrooptically, by changing the index of refraction of an electrooptical material by controlling electric fields applied thereto. A plurality of electrodes are disposed on one surface of the electrooptic material and a ground electrode is disposed on the other. The electrodes are adapted to apply electric fields derived from a voltage source to the electrooptic material that selectively changes its index of refraction and provides for a predetermined index of refraction profile along at least one dimension thereof, thus forming a lens. By appropriately forming the electrode pattern and properly controlling the voltages applied thereto, differing lens shapes may be formed. Since the response times of the electrooptic materials employed in the present invention are on the order of nanoseconds (10-9 sec) or less, the intrinsic response frequency of the lens system is 109 Hz or more. The present invention thus increases the data storage and retrieval capacity of optical systems in which it is employed.

公开(公告)号：WO1993015531A1

公开(公告)日：1993-08-05

申请号：PCT/US1993000763

申请日：1993-01-26

Applicant: HUGHES AIRCRAFT COMPANY

Inventor： HUGHES AIRCRAFT COMPANY ,  CHANG, David, B. ,  VALI, Victor

IPC: H01Q21/22

CPC classification number: H01Q21/22 ,  H01Q3/2676

Abstract: To reduce the sidelobe levels in a beam produced by an optical phased array, the array is arranged so that the output fields of the emitters have the amplitude and phase given by the inverse Fourier transform of the desired radiation pattern.

Abstract translation: 为了减少由光学相控阵产生的光束中的旁瓣电平，阵列被布置成使得发射器的输出场具有通过所需辐射图的傅里叶逆变换给出的幅度和相位。

公开(公告)号：WO1993003424A1

公开(公告)日：1993-02-18

申请号：PCT/US1992005042

申请日：1992-06-15

Applicant: HUGHES AIRCRAFT COMPANY

Inventor： HUGHES AIRCRAFT COMPANY ,  VALI, Victor ,  LAWRENCE, Albert, F. ,  CHANG, David, B.

IPC: G03F07/20

CPC classification number: G21K1/06 ,  G03F7/70158 ,  G03F7/70316 ,  G21K2201/062

Abstract: A dislocation-free, composite-substance crystal having a lattice constant which decreases over the length of the crystal (38) convergently focuses beams of hard X-rays or gamma rays (11). A single-substance, dislocation-free crystal (34) collimates diffuse beams of hard X-rays or gamma rays and projects the collimated radiation (11') to the focusing crystal (38). A mask (36) is interposed between the collimating crystal (34) and the focusing crystal (38) causing the collimated radiation (11'') to carry an image of the mask (36). The focusing crystal (38) produces a convergent hard X-ray beam or gamma ray beam (11''') to focus a reduced image of the mask (36) upon the photosensitive layer (41) of a wafer (39). An example of a dislocation-free crystal having a lattice constant which decreases over its length (38) is a dislocation-free silicon-germanium crystal (20) wherein the proportion of germanium to silicon varies over the length of the crystal.

公开(公告)号：WO1991005279A1

公开(公告)日：1991-04-18

申请号：PCT/US1990005619

申请日：1990-10-03

Applicant: HUGHES AIRCRAFT COMPANY

Inventor： HUGHES AIRCRAFT COMPANY ,  BROWNRIGG, Patrick ,  VALI, Victor ,  YOUMANS, Bruce

IPC: G02B06/16

CPC classification number: G02B6/02

Abstract: An optical fiber is constructed by selecting a first material for a core of the optical fiber. The first material has a known coefficient of thermal expansion, α1, and a known temperature dependent rate of change, dn/dT, of an index of refraction, n. A second material (cladding) has a predetermined coefficient of thermal expansion, α2, and a radius, R2, about the axis of the fiber. The radius, R2, of the cladding is determined such that an effective coefficient of thermal expansion for the fiber is substantially equal to the negative of the product of the reciprocal of the index of refraction of the first material and the temperature dependent rate of change of the index of refraction of the first material, i.e. α = (-1/n)dn/dT.

公开(公告)号：EP0446349A1

公开(公告)日：1991-09-18

申请号：EP90916855.0

申请日：1990-10-03

Applicant: HUGHES AIRCRAFT COMPANY

Inventor： BROWNRIGG, Patrick ,  VALI, Victor ,  YOUMANS, Bruce

IPC: G02B6

CPC classification number: G02B6/02

Abstract: On produit une fibre optique par sélection d'un premier matériau constituant l'âme de la fibre optique. Le premier matériau a un coefficient de dilatation thermique connu alpha1, et une vitesse de changement dépendante de la température connue, dn/dT, d'un indice de réfraction n. Un second matériau (gainage) a un coefficient de dilatation thermique prédéterminé, alpha2, et un rayon, R2, autour de l'axe de la fibre. Le rayon, R2, du gainage est déterminé de sorte que le coefficient de dilatation thermique effectif de la fibre est sensiblement égal à la valeur négative du produit de l'inverse de l'indice de réfraction du premier matériau et de la vitesse de changement de l'indice de réfraction dépendante de la température du premier matériau, c'est-à-dire alpha = (-1/n)dn/dT.

公开(公告)号：EP0470239A1

公开(公告)日：1992-02-12

申请号：EP91905500.0

申请日：1991-02-11

Applicant: Hughes Aircraft Company

Inventor： VALI, Victor ,  CHANG, David, B. ,  BROWNRIGG, Patrick, C.

IPC: G01F23

CPC classification number: G01F23/292 ,  Y10S250/904

Abstract: Jauge de niveau de carburant ou de liquide à fibres optiques déterminant le niveau de liquide par mesure de la quantité de perte de lumière due au transfert évanescent vers le carburant ou le liquide. Une fibre optique est supportée dans le réservoir de carburant ou de liquide, une première extrémité adjacente au niveau de liquide le plus élevé possible à mesurer, un réflecteur se situant au niveau de la première extrémité. La fibre optique s'étend vers le bas dans le réservoir, et sa seconde extrémité est connectée à une source de lumière afin d'injecter de la lumière dans la fibre. On compare l'intensité de la lumière entrée à l'intensité de lumière réfléchie par la première extrémité de la fibre, et on calcule le niveau de liquide à partir de la perte de lumière. La jauge présente une fiabilité très élevée puisqu'elle ne comporte pas de parties mécaniques mobiles.

公开(公告)号：EP0581948A1

公开(公告)日：1994-02-09

申请号：EP93905835.0

申请日：1993-02-08

Applicant: Hughes Aircraft Company

Inventor： CHANG, David, B. ,  VALI, Victor

IPC: G02F1 ,  G02F2 ,  H01S3

CPC classification number: H01S3/0057 ,  G02F1/0134 ,  G02F1/035 ,  G02F2203/26

Abstract: L'invention concerne un procédé et un appareil de raccourcissement de la longueur d'une impulsion de lumière. Le procéde consiste à modifier l'indice de réfraction d'un milieu optique (14) dans lequel l'impulsion de lumière se déplace sur une aire du milieu (14) où l'extrémité avant de l'impulsion de lumière se situe, de sorte que l'extrémité avant de l'impulsion de lumière se déplace plus lentement que l'extrémité arrière, permettant ainsi à cette dernière de rattraper l'extrémité avant afin de raccourcir la longueur de l'impulsion. Pour ce faire, on génère un champ électrique dans le milieu optique (14) au moyen d'un milieu porteur de charge (12) positionné par rapport audit milieu optique (14), de manière que l'indice de réfraction est modifié par l'effet électrooptique. De plus, il est possible de modifier l'indice de réfraction du milieu optique (14) en l'entourant d'un matériau piézo-électrique (20), et par application d'un champ électrique audit matériau piézo-électrique (20) de manière que celui-ci comprime le milieu optique (14), modifiant ainsi l'indice de réfraction.