Siemens Aktiengesellschaft

Hans Eschler

Gerd Goldmann

Hartwig E Ruell

Dietlind Pekau

Horst Kiemle

Peter Graf

Rudolf Oberbacher

Manfred Lang

Wolf E Bulst

Ulrich V Hundelshausen, Deceased

By Irmela Bismarck, Heir

By Burkhard Hundelshausen, Heir

An acoustic wave filter comprising a piezoelectric substrate body upon which at least two digital structures are formed and which comprise input and output transducers and form a selective wave reflective pair with at least one of the digital structures having a wide band amplitude characteristic F1 and at least one of the other digital structures having a narrower frequency band amplitude characteristic and wherein the center frequency f1 of the wider band F1 digital structure is displaced relative to the center frequency f2 of the digital structure which has a narrower frequency band F2 by a frequency of .DELTA..sub.f on either side of the center frequency f1 so that one of the zero locations f.sub.R1'2 of the distortion signal F.sub.R of interdigital reflections is placed close to the value of the center frequency f.sub.0 of the filter.

Acoustic wave filter

A process and apparatus for non-mechanically deflecting of a light beam with high resolution characterized by passing a linearly polarized beam through at least one electro-optical deflector and preferably two to obtain four possible beam directions, passing the four beam directions through a multicomponent deflector of prisms which direct each of the four beam directions to a given point on an acousto-optical light deflector which is a two-dimensional acousto-optical light deflector that deflects the beam into two-dimensional arrays on a screen or storage medium, with each one of the four beam directions causing the two-dimensional arrays to be disposed in a different quadrant of the screen or medium. Preferably, the beams leaving the acousto-optic deflector are passed through a four component polarizing filter which prevents undesired overlap between the zero order undeflected portion of the beam and the first orders. In one embodiment, at least one of the electro-optical deflectors which comprises a polarization switch or rotator and a polarization dividing filter which is a birefringement discriminator, such as a Wollaston prism or a Nicols prism is separated with the polarization switch disposed ahead of the acousto-optical deflector and the polarization dividing filter receiving the deflected beams from the acousto-optical device.

Process and apparatus for high resolution non-mechanical deflection of

An acousto-optical component or other high frequency and wide-band ultrasonic component comprises a piezoelectric transducer and a crystalline or glass sound medium which are bonded together by a multi-layer metal molecular adhesion bond. During fabrication, the surfaces of the piezoelectric body and the sound medium which are to be connected are first polished to a degree of smoothness which is well below that of a Newton ring. These surfaces are then completely cleansed and a first metal layer having a thickness of 0.5-2 nm is vapor deposited onto each the cleansed surfaces. Next, a second metal layer having a thickness of 5-20 nm is vapor deposited onto each of the first layers. The transducer is then applied, by molecular adhesion, to the sound medium. To form a strong and reliable bond, only moderate pressures of about 250 to 1500 psi are necessary. A metal layer having a thickness of 0.3-0.6 .mu.m is vapor deposited over an extending portion of the multi-layer bond as a terminal for connection to a high frequency supply. Subsequently, the transducer is ground to a desired thickness in order to obtain a desired resonant frequency and a second electrode is applied to another surface of the piezoelectric body for connection to the high frequency supply.

Techniques for producing an acousto-optical component or a wide-band

A linear data input transducer for modulating an object beam from a laser which is subsequently projected along with a reference beam onto a storage medium to holographically record data characterized by the transducer having a first acousto-optical light deflector for deflecting the object beam in a first direction, a second acousto-optical light deflector for deflecting the beam in a second direction, each of the first and second deflectors having sound waves extending at right angles to each other, and a device for applying a signal input to each deflector which includes a chain of high frequency oscillators which are independently actuated and an adder circuit for combining the output of the oscillators into the signal input. In one embodiment of the invention, the transducer has a single acousto-optical cell with the sound transducers disposed on the surface extending at right angles so that the transducer is a compact light deflector. In another embodiment, the transducer is composed of two separate cells which are aligned with the second light deflector receiving the beams deflected by the first light deflector.

Linear data input transducer

Apparatus and method for holographic storage of data utilizing a light source and a number of light deflectors such that a single beam can be used to read data from a number of different holograms simultaneously.

Apparatus and method for holographic storage of data

The present invention is directed to the improvements in an apparatus for holographically recording data on a storage medium with the data being block-organized holographic data by spatially modulating a laser beam into a plurality of object beams which are directed at a storage medium to interfere with a reference beam to form the holographic recording. The improvements are that the means for spatially modulating comprises an acousto-optical light deflector having a large area, piezoelectric sound transducers disposed on the one side thereof, the sound transducer having n electrodes spaced thereon to form n transducer units which receive a signal with a frequency mixture of m frequencies to deflect the beam passing through each unit into m beam directions with the light frequency of each beam having a Doppler shift associated with the amount of deflection. The apparatus also includes providing a lens raster consisting of n times m lens elements arranged in a manner to widen each of the object beams to illuminate the entire hologram and means for compensating for the Doppler shift in the light frequencies of the object beams.

Acousto-optical data input transducer with optical data storage and

An acousto-optic light deflector for controllably deflecting light beams in an optical system characterized by the deflectors being arranged in a matrix and wherein each deflector has a shape so that a standing sound wave is utilized to form a phase grating therein. Each of the units is provided with a piezoelectric transducer which creates a high frequency ultrasonic standing wave having a frequency between 30 and 200 MHz. The system may include an optical device for focusing all of the beams deflected in the same direction to a single spot on a plane.

Apparatus and process for deflecting the direction of light beams in a

A method and apparatus for recording data in parallel extending information channels or tracks on a storage tape characterized by the object beam and reference beam being commonly and sequentially deflected in a direction perpendicular to the parallel information tracks or channels. The invention is also directed to a method of retrieving or reading-out the information which includes focusing a retrieval beam on the tracks with a cylindrical lens to either simultaneously illuminate each of the tracks and sequentially detect the information contained in the individual tracks or deflecting the focused beam sequentially in a vertical direction from track to track for sequentially retrieving the information recorded thereon.

Growing community of inventors

Munich, Germany

Hans Eschler