Abstract: A high frequency transducer having a dome diaphragm with a configuration of a bisected ellipse to overcome the distortion and breaking point of prior art even domes at frequencies above 30 kHz. The dome diaphragm having an annular skirt extending therefrom in an integral fashion and connecting to a disc shaped plate of the transducer. A voice coil of cylindrical section being directly connected to the skirt at a region of close proximity to said dome. The dome being constructed of a rigid material such as a metal, an alloy, a metalloid such as, but not limited to, titanium, aluminum, and boron, or a combination thereof. The dome being constructed in accordance with a general formula for an ellipse (x2/a2)+(y2/b2)=1, and a>b. Wherein a is half of the distance of major axis and b is half of the distance of a minor axis.

Abstract: A method of inserting additional information, such as a digital signature, in a digital image comprises the following steps: detecting (E10) the points of interest in said image (I); selecting (E11) a subset of points of interest adapted to define a geometric reference frame in said image (I); calculating (E12), for the geometric reference frame, reference information necessary for determining the geometric transformation applied to the image for a class of predetermined geometric transformations; coding (E13) said reference information in a reference key (Kr); and inserting (E16-E19) the additional information in said digital image (I). Use notably for geometrically re-fixing the image before extracting the signature.

Abstract: Methods and apparatus for watermarking a digital media object, and for detecting watermarks, are presented. The basic concept underlying the disclosed approach is watermarking/detection in a transform space that allows the same level of watermarking to be applied to all samples. For instance, in one embodiment, a watermarking system first nonlinearly transforms the original signal to a perceptually uniform domain, and then embeds the watermark in this domain without varying the statistical properties of the watermark at each sample. At the watermark detector, a candidate image is transformed to the same perceptually uniform domain, and then correlated with the original watermark sequence. Under such conditions, it is shown that an optimal watermark detector can be derived. This approach is particularly attractive when the original image is unavailable at the detector, as it effectively prevents the image content from biasing the watermark detection score.

Abstract: A method for embedding a watermark signal that contains message data in a digital image sequence having two or more frames, includes the steps of: producing a set of two or more different carrier signals from a single secure key; assigning a carrier signal from the set of carrier signals to each frame in the sequence; and embedding a watermark signal in each frame using the corresponding assigned carrier signal.

Abstract: The present invention is embodied in a system and method for performing sparse transformed template matching using three dimensional rasterization by comparing and matching a first set of digital data to at least a second set of digital data. The system and method includes raster transforming at least one of the first set of digital data and the second set of digital data, placing multiple images of the digital data in texture memory as multiple textures, gathering statistics between the textures and statistically comparing and matching the raster transformed sets of digital data to appropriately corresponding portions of each other. The first or the second set of digital data can be transformed during statistical analysis to enhance statistical analysis of the digital data.

Abstract: A method and an apparatus for inspecting microbes, etc. including, as an apparatus for detecting microbes, etc., a cultivating device, an image taking-in device, and an arithmetic processing unit, in which an image of a medium to be inspected obtained from a sample collected from a substance or a physical solid having proper color microbes or the medium subjected to illumination treatment, dyeing treatment, etc. prior to or after cultivation in accordance with necessity is separated into the three primary colors, or the like, then, chromatic information of histogram, color and hue for each primary color are calculated, and the information thus obtained is compared with integrated data obtained by combining second data of generic information of microbes, etc. with first data of microbes, etc.

Abstract: A method for processing a digital image of a document to provide one or more bitonal digital copies of selected image quality that are optimized for specific purposes. The method is suited for use with such documents as bank checks and commercial forms that have printed or handwritten textual characters overlaid on potentially obscuring backgrounds. The method may provide a clean bitonal digital copy with reduced background optimized for use in optical character recognition or an archival copy with meaningful background retained that is optimized for archiving the original document. A set of bitonal copies of the digital image of a document is derived covering a range of contrast sensitivities. The copies are compared and a numerical measure is provided representing the amount of change in going from one copy to the next. The collection of such numerical measures defines a numerical sequence representing variations in the digital image as the contrast sensitivity is monotonically varied.

Abstract: The present invention comprises a digital image processing method for detecting human eyes in a digital image. This method comprises the steps of: detecting iris pixels in the image; clustering the iris pixels, and selecting at least one of the following methods to identify eye positions: applying geometric reasoning to detect eye positions using the iris pixel clusters; applying a summation of squared difference method using the iris pixel clusters to detect eye positions; and applying a summation of squared difference method to detect eye positions from the pixels in the image. The method applied is selected on the basis of the number of iris pixel clusters. In another embodiment, the present invention also comprises a computer program product.

Abstract: The present invention is embodied in a system and method for detecting a face within an image using a relational template over a geometric distribution of a non-intensity image property. In general, the system of the present invention includes a hypothesis module for defining a sub-region in which to search for a face, a feature extraction module for extracting image feature values image based on a non-intensity image property, an averaging module for grouping the extracted image feature values into geometrically distributed facial regions, and a relational template module that uses a relational template and facial regions to determine whether a face has been detected. In a preferred embodiment the image property used is edge density, although other suitable properties (such as pixel color) may also be used.

Abstract: A method beginning at (10) is provided for creating high-fidelity visible coloring from infrared images of a scene under surveillance. The infrared images captured at (12) are analyzed at (14) to determine if an object, such as a face, is identifiable within the image. If an object is identifiable at (16) the object features are compared to a plurality of stored object features at (20). If there is a match at (22), the color characteristics of the object are obtained at (24) and the object is colored at (26) based on the stored database feature information. If there is no match at (22) or identifiable object at (16) and object color cannot be identified at (23), the image is analyzed at (28) to determine if a pattern, such as clothing, is identifiable within the image. If a pattern is identifiable at (30), the color characteristics of the pattern are obtained at (34) and the pattern is colored at (36) according to infrared reflectance characterization in conjunction with the stored pattern information.

Abstract: A method for providing a preliminary diagnosis of skin cancer, more specifically a screening risk assessment of pigmented lesions receiving digital photographs of skin abnormalities from a plurality of consumers at a server, receiving medical information related to each of the plurality of consumers at the server, assigning an identification to at least one of the consumers and the digital photographs, reviewing the digital photographs and categorizing the digital photographs into at least three categories so as to define category information, the at least three categories including a first category of a first risk, a second category of risk lower than the first category and a third category of insufficient photograph quality, and providing the category information as a function of the identification.

Abstract: A method of forming an image of detailed cilium wrapped by mucus which exists in the epithelial layer of a cellular structure of a bronchus, where the method includes the steps of: irradiating an illumination light to the epithelial layer; generating Fresnel reflected light; irradiating the Fresnel reflected light to an image pick-up optical system; enlarging the Fresnel reflected light by the image pick-up optical system so that the enlarged Fresnel reflected light can be received by the image pick-up element; scanning at a velocity which is more than the velocity of motion of the cilium by the image pick-up element; transmitting image information from the image pick-up element to an observable medium with the naked eye; and displaying the image of detailed cilium by the observable medium.

Abstract: A method of determining the orientation of subject data in a two-dimensional data set includes: determining a center of the subject data; determining angles from the center to each subject data; generating a frequency distribution based on the angles; and determining the orientation of the subject data based on the frequency distribution.

Abstract: A system digitizes a three-dimensional object as a three-dimension model by placing the object on a turntable while taking two sets of corresponding images. The first set of images and the second set of images are obtained while rotating the turntable to a various positions and illuminated the object with the overhead lights and backlights. There is a one to one correspondence for images in each set for each position of the turntable. Object shape data and texture data are respectively extracted from the first and second set of images. The object shape data is correlated with the object texture data to construct the three-dimensional digital model stored in a memory of a computer system.

Abstract: A system and method for processing digital video. The invention allows for manual level and gain adjustment of the video similar to that used in a histogram based automatic level and gain control system using a cumulative distribution function. Level changes are made by an offset to the existing automatic level and gain. Level changes are first made by applying an offset L and the midscale gray intensity bin on the histogram is located. Gain changes are made by changing the relative gain multiplier (G) which acts on the automatic level and gain algorithm causing the gain to change equally about midscale gray (i.e., midscale gray is maintained). In accordance with the invention, as part of the histogram based manual level and gain algorithm, the local gain is clipped to a predetermined maximum in order to prevent an overly noisy picture when too much gain is applied. The inventive method determines how to prevent a shift in the level when increasing the gain (i.e., G>1) even when clipping is applied.

Abstract: A histogram is modified by using an adaptive system. Two different thresholds are set: a threshold of a number of pixels which can be changed, and another threshold indicative of a total number of pixels which can be combined together. The thresholds can be adaptively based on results of frame operations.

Abstract: The invention relates to improving the functions and applicability of a mobile station (201), (301), (401). Advantageous embodiments of the invention include a method in which graphic information may be input to a terminal equipment via a touch-sensitive writing pad and at the same time presented on a display in parallel with the independent execution of other functions, and a portable terminal equipment according to the method, which comprises a voice communicator (for text and file storage and transmission functions) and a display for presenting visual information as well as a graphic writing pad for entering input data in graphic format to the terminal equipment. In a communicator according to an embodiment of the invention a video terminal may be used in the information input simultaneously as a graphic writing pad and a display of the video terminal. The invention enables deaf and dumb people to communicate and take part in a video conference, for example.

Abstract: A method and image processing system are disclosed that extract feature information from an image using a model. An object in the image is first identified. The model is used at the front-end to quickly determine/define the approximate location/position of specific features of the object. Based in this modeling information, the location/position of the specific features are then determined. A feedback process may also be used to update/customize the model and improve performance.

Abstract: The present invention is directed to a method for extracting textual as well as tabular data material from financial documents. Initially, a comparison is made to determine the type of data schedule material provided in the document. Subsequently, the character strings of the financial document are compared to character strings provided in previous documents or in various databases. The database of the previous document would include the textual material in a first plane, and the tabular material also in that first plane. If a character string match is made between a new document and an old document, the new tabular data material would be provided in a data matrix in a second plane but the corresponding textual material would not be included in the textual matrix provided in that second plane. Only character strings not matched in the textual material of the first plane would be provided in the textual matrix of the second plane.

Abstract: A method or apparatus according to an embodiment of the invention allows for entry of multi-stroke characters via a natural drawing interface and without requiring an expensive stylus-drawing surface combination.

Abstract: An object recognition system including a position sensor, an image sensor and a controller is provided. The position sensor determines the position of an object, and the image sensor captures an image of the object. The controller sets a processing area within the image captured by the image sensor based on the position of the object determined by the position sensor and a predetermined size for the object to be recognized. The controller extracts horizontal edges from the processing area, and judges whether each of the extracted edges belongs to the object based on characteristics of the object to be recognized. More practically, the controller can check if each of the extracted edges contains a pixel on a boundary of the processing area. If so, the controller judges to the edge to belong to an object other than the object. The controller can also examine the linearity of each of the extracted edges.

Abstract: A method and apparatus is described for providing a camera accessory to a wireless mobile terminal in a wireless radiocommunication system. The wireless mobile terminal has an image data interface and a physical interface for detachably coupling the camera accessory thereto. One or more frames of image data is captured in the camera accessory and compressed according to one or more compression formats. The captured and compressed frames are transferred to the wireless mobile terminal over the image data interface. The camera accessory does not include a display. Image data is captured in a predetermined format including a CIF format. Still image frames are compressed using a JPEG format and an image stream is compressed using an MPEG format. The captured and compressed frames are transferred to the wireless mobile terminal over the image data interface using respective predetermined formats including RGB CIF, YUV CIF, JPEG, MPEG, and MPEG-4 with CIF to QCIF conversion format.

Abstract: A method and apparatus for reducing information artifacts imparted to a decoded video information stream by an MPEG-like decoder utilizing discrete transform (DCT) domain compression to produce a size-reduced reference image information frame. Specifically, the invention responsively selects one of a plurality of pre-defined DCT coefficient matrices in response to the amount of compression to be imparted to the reference image information frame, and the presence or absence of field-mode encoding the reference image information frame.

Abstract: A compression and decompression apparatus, method and computer program product, wherein compression and decompression of image data is performed via a combination of two-dimensional reversible wavelet transform processing, context model processing, and binary entropy encode/decode processing. Faster processing, as compared to conventional devices and methods, is achieved by performing the context model processing and the binary entropy encoding/decoding processing in parallel, such that two-story pipeline processing is performed, resulting in a reduction of a basic cycle time.

Abstract: An image data compression technique includes division of an image data stream into a plurality of subregions and optimal compression of each subregion. The subregions may represent adjacent pixels in a reconstructed image, and may all be of the same length. The length of the subregions may be set to a default, and may be altered based upon image characteristics. The subregions are analyzed for selection of an optimal compression algorithm for each subregion from a set of candidate algorithms. Criteria for selection of the optimal algorithms may include the relative entropy levels of data within the subregions, and the length of compressed data code resulting from application of each of the candidate algorithms.

Abstract: An image coding apparatus according to the present invention is provided with, as shown in FIG. 4, a blocking circuit 401 for dividing an input image signal into two-dimensional blocks each comprising plural pixels; a frequency distribution verifier 408 for calculating the average and variance from a plurality of image feature data 402 to 407 and the frequency distribution of each feature data for each block in a predetermined period; a filter characteristic decider 409, a filter circuit 410, and an encoder 411. In the image coding apparatus so constructed, the input image signal is divided into local regions each comprising plural pixels, the image feature data of each local region is extracted, the average and the variance of the extracted image feature data are calculated from the frequency distribution of the image feature data for a predetermined period, and a filter characteristic and a quantization step are decided for each local region according to the degree of singularity of each local region.

Abstract: Compressed image data is input, and it is checked according to the attributes of that image if the compression ratio of the compressed image is to be changed by a compression ratio determination unit. A compression ratio change unit changes the compression ratio of the compressed image to increase by deleting a high-frequency subband or lower bit plane of the compressed image data. Upon changing the compression ratio, codes of a non-region-of-interest of that image data are deleted, and if a desired compression ratio cannot be obtained by only such deletion, codes of a region of interest of that data are deleted to change the compression ratio.

Abstract: A system and method for compressing a video image. The system includes an object database and a compression processor coupled to the object database for receiving video image information from a video source. The compression processor includes an image analyzer for determining status of one or more pixels of the video image over time, a shape determiner for determining a shape that defines a group of pixels that are determined to have the same status over a period of time, an object retriever for retrieving an object from the object database that corresponds to the determined shape from a stored set of objects, and a saving component for saving information relating to the selected object and dimensional information of the determined shape.

Abstract: A reversible Discrete Cosine Transform (DCT) is described. The reversible DCT may be part of a compressor in a system. The system may include a decompressor with a reversible inverse DCT for lossless decompression or a legacy decompressor with an inverse DCT for lossy decompression.

Abstract: Disclosed is an input image data compressor which comprises an image recording controller for generating image information on respective input objects from the input image data, generating image information on a moving object using the image information, comparing the previously input image data with the presently input image data, generating new image information on the moving object and compressing the new image information; a storage unit for storing signals or data generated during compression operation of the image recording controller in a corresponding established address; and a compressed image storage unit for storing the compressed image data compressed by the control operation of the image recording controller.

Abstract: Images are to be efficiently and easily encoded while suppressing block distortion and pseudo-contour generation. A quantization characteristics determining unit receives pixel values from a pixel value input unit, measures the length S of the consecutive occurrence of the same pixel values in connection with a pixel to be encoded and the pixel value differences D, and determines quantization characteristics n with reference to the result of sensory evaluation. A quantization/inverse quantization unit quantizes pixel values to be inputted with the quantization characteristics n, and further inverse quantizes them to reduce the number of gray-scale levels. The output pixel values of the quantization/inverse quantization unit are encoded and outputted by an entropy encoding unit.

Abstract: A system and method are provided for digital image enhancement. In one example of an embodiment, the system includes a processor and a memory that are electrically coupled to a local interface that may be, for example, a data bus and associated control bus. The system also includes a display electrically coupled to the local interface through a display interface. Stored in the memory and executed by the processor is image enhancement logic. The image enhancement logic includes logic to generate a user interface displaying a digital image and at least one image parameter adjustment mechanism. The image enhancement also includes logic to adjust at least one image parameter of the digital image in response to a manipulation of the image parameter adjustment mechanism, thereby altering the digital image displayed in the user interface.

Abstract: A detector imaging system having an apparatus and method for correcting defective pixels in a current acquired image is disclosed herein. The system performs the correction of defective pixels using image feature information and temporal information. The system includes a correction scheme which includes determining a temporal matrix based on the current acquired image, at least one prior acquired image, and a filter weight; determining a local gradient based in part on the temporal matrix and a gradient kernel; and providing a correction value based on the local gradient to correct the defective pixel. The correction scheme is repeated a plurality of times as desired to correct all the defective pixels in the current acquired image.

Abstract: A tone correction system, method and interface is described in which a digital image is initially filtered to obtain a corresponding locally averaged value for each pixel value of the image. The image is optimally filtered using a cone-type filter having a small filter radius and which favorably weights the center pixel values of the radius. Shadow and highlight values are obtained from selected shadow and highlight functions, respectively, using the locally averaged values. A tone function is derived from each of the shadow an highlight values for each pixel. Each pixel value of the image is then remapped according to its derived shadow and highlight tone functions. The tone corrected image can be reinteratively corrected by adjusting parameters of the shadow and highlight functions and remapping the image data until a desired image quality is achieved.

Abstract: An image input device identifies what part of the optical input system needs cleaning when there is dust or other foreign matter in the optical input system. This image input device has an image noise position detector for capturing image data from a scanner, and detecting the main scanning address of noise information corresponding to image noise present in the image data; a focus calculator for calculating focus information around the main scanning address detected by the image noise position detector; focus information storage for storing focus information for each subscanning line; and a foreign matter position determining circuit for determining the location of foreign matter on the scanner based on the focus information stored in the focus information storage.

Abstract: One aspect of the invention is a method of automatically enhancing a digital image. The magnitudes of grain traces are measured in at least two segments in the digital negative and the digital negative is enhanced using the magnitudes of the grain traces measured in the at least two segments.

Abstract: A method and apparatus for searching, browsing and summarizing moving image data using the fidelity of a tree-structured moving image hierarchy, which can partition or divide the moving image data into predetermined units, extract a key frame or representative frame from each of the partitioned or divided units, create a tree-structured key frame hierarchy on the basis of the extracted key frames, store a fidelity value of each of the key frames, which is a sub-tree information representative degree of each key frame, at an edge between adjacent ones of the key frames and effectively and efficiently search, browse and summarize the moving image data using the stored fidelity values. Therefore, a query image or video clip desired by a user can more rapidly and accurately be searched for.

Abstract: Images in an image database are indexed according to semantic labels from a surface color code book in order to allow querying and retrieving of images based on color content. Regions of unsegmented images in a database are localized and described with semantic labels from a surface color code book. A database index is then built using this image region information and corresponding labels. This pre-generated color-region index allows querying by semantic labels in order to locate and retrieve similar images from a database. Querying for similar images by presenting a target image is also possible using the described color-region index. In this second type of query mode a target image is analyzed to determine semantic labels of color surfaces present in that image and these labels, in turn, are used to locate similar entries in the color-region index.

Abstract: A sensing device for sensing region identity data and generating movement data when the sensing device is moved relative to a region of a surface, the region identity data being indicative of an identity of the region, the movement data being indicative of the movement of the sensing device relative to the region, the surface having disposed upon it coded data indicative of at least one region associated with the surface, the sensing device including: region identity sensing means configured to sense the region identity data using at least some of the coded data; motion sensing means configured to generate the movement data; and communications means configured to communicate the region identity data and the movement data to a computer system.

Abstract: A method of thermally poling a silica based waveguide (12) comprises exposing a region of the waveguide (12) to an electric field (for example, via capillary electrodes (22, 24) inserted into holes in the waveguide); directing a laser beam (18) into the region exposed to the electric field to effect localized heating of the region via direct absorption; and scanning the laser beam (18) over the region at a rate selected to avoid heating of the region above the glass transition temperature. Reversing the electric field while scanning the laser beam (18) allows the formation of periodic poled gratings. The waveguide (12) can comprise an optical fiber.

Abstract: An optical switch includes at least one light-receiving core for receiving an optical signal, a plurality of light-emitting cores which are used selectively for emitting the optical signal, and a plurality of waveguides connecting the light-receiving core and the plurality of light-emitting cores. A nonlinear optical element which, when pumped, changes its refractive index by 2% or above relative to the surroundings to control a traveling direction of the optical signal is disposed near at least one of the plurality of waveguides.

Abstract: A device for compensating the polarization dispersion suffered by an optical signal when it is transmitted by an optical line includes a polarization controller. It generates a differential time delay between two orthogonal polarization modes and controls the polarization controller so that it converts the signal transmitted by the line into a compensated optical signal. If the quality of the compensated optical signal remains below a reference quality the device modifies the state of polarization of the optical signal. Applications include long distance optical transmission via standard fibers.

Abstract: A chiral fiber sensor implemented in a chiral fiber is provided that mimics advantageous optical properties of a cholesteric liquid crystal structure. In a passive sensor embodiment the chiral fiber sensor of the present invention includes a chiral fiber element configured to shift its reflection band in response to a change in a particular external condition (such as temperature, pressure and axial twist). The chiral fiber element is subjected to a broadband emission while monitoring its refection or the transmission spectrum. Changes in the monitored spectrum indicate changes in the particular external condition. In an active sensor embodiment, the chiral fiber element is configured as an optically pumped chiral laser having a lasing wavelength that shifts in response to a change in a particular external condition (such as temperature, pressure and axial twist). The lasing wavelength is monitored and shifts in the wavelength indicate changes in the particular external condition.

Abstract: A method for maximizing light transmission through an optical switch which includes a first mirror to direct a beam of light received from an input optical port to a second mirror that redirects the beam of light to an output optical port, the first and second mirrors each being pivotally actuated in first and second directions. The input and output mirrors are simultaneously moved through a sequence of coordinate positions about an origin, the input and output mirrors moving in both the first and second directions, with a light intensity value being read at each coordinate position to find a maximum light intensity value. It is emphasized that this abstract is provided to comply with the rules requiring an abstract that will allow a searcher or other reader to quickly ascertain the subject matter of the technical disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims.

Abstract: The invention relates to a receiver optical sub-assembly (ROSA) for use in a high-speed small-form factor transceiver. The ROSA, according to the present invention, includes a stacked chip design in which a semiconductor micro-bench, upon which the photodiode and trans-impedance amplifier are mounted, is disposed perpendicular to the direction that the light travels. A flexible electrical connector is attached to the semiconductor micro-bench for electrically connecting the ROSA to a host a transceiver device. The flexible electrical connector is fixed to the surface of the semiconductor micro-bench with portions cut-out to receive the amplifier and other electrical components extending therefrom. To facilitate assembly, wells are etched from the semiconductor micro-bench corresponding to bumps extending from a mounting flange for the optical coupler.

Abstract: The Multimode Interference coupler according to the invention has smoothly continuous inwardly tapered sidewalls (301) which define the width of the multimode region (W1) along the propagation axis of the device. The inward taper causes the average width of the device to be reduced in comparison to known couplers having straight sidewalls (202). Further, invention allows the access waveguides (303, 309) to remain sufficiently spaced, while reducing the overall length of the device, to avoid lithographic gap fill-in and unwanted optical coupling between the waveguides.

Abstract: Described is a device for directing an optical signal from a first optical fiber (101, 102, . . . ) along one of a plurality of selectable switching paths each terminating in a corresponding one of a plurality of second optical fibers (401, 402, . . . ) via an optical element (201, 202, . . . ), the optical element (201, 202, . . . ) being moveable by a controllable actuator (60) from a first to a second position to change the switching path of incident optical signal. The optical element (201, 202, . . . ) is slideably mounted in parallel to a first mounting plate (10) comprising a conduit (11) through which the optical signals from the first optical fiber (101, 102, . . . ) can be directed by the optical element (201, 202, . . . ) along the selected one of the switching paths to one of a plurality of conduits (21) in a second mounting plate (20) parallel to the first mounting plate (10), and further to the corresponding one of second optical fibers (401, 402, . . . ).

Abstract: Methods, apparatus and systems for signaling information between an optical cross-connect switch and attached network equipment such as Internet Protocol (IP) routers, WDM terminals, SONET add/drop multiplexers and ATM switches. In one embodiment, an out-of-band signaling interface between an optical cross-connect switch and attached network equipment is realized by using an out-of-band communication channel over a network. In another embodiment, a decentralized signaling interface is provided by one or more dedicated signal lines between an optical cross-connect switch and attached network equipment.

Abstract: A free space all-optical crossbar switches light from a plurality of sources onto a plurality of receivers, in any arbitrary permutation or combination (including one-to-one and many-to-one permutations). The sources and receivers may, for example, be single mode optical fibers. The polarization of the light from each source is controlled by a series of polarization control devices associated with the source so as to obtain desired angular deflections through a series of polarization-dependent angular deflectors in a first deflection unit. A lens may then direct the light from each source towards its desired receiver. An optional second deflection unit containing polarization control devices associated with individual receivers redirects the light so that it is incident normally on the receivers, an advantage if the receivers are single mode optical fibers. Alternative embodiments are described to reduce the number of optical components and to provide uninterrupted high speed data flow.

Abstract: An optical switch has first to fourth optical matrix switches in each of which a plurality of 2-input/2-output optical switch elements are arranged in a matrix to form a plurality of input ports, a plurality of auxiliary input ports, a plurality of output ports, and a plurality of auxiliary output ports. The auxiliary output ports in the first optical matrix switch are connected to the respective input ports in the third optical matrix switch, the output ports in the second optical matrix switch are connected to the respective auxiliary input ports in the third optical matrix switch, the output ports in the first optical matrix switch are connected to the respective auxiliary input ports in the fourth optical matrix switch, and the auxiliary output ports in the second optical matrix switch are connected to the respective input ports in the fourth optical matrix switch.