Abstract: Methods for imaging patterns of features by thermal transfer involve controlling intensities of a plurality of beams. The intensities of beams that image edge portions of a feature may be set to be different from the intensities of beams that image interior portions of the feature. Beams that image home and away edges of a feature may be controlled to have different intensities. Apparatus for imaging patterns of features may comprise a controller configured to maintain intensity information for channels of a multi-channel imaging head. The controller uses the intensity information to set intensities of those channels that correspond to edge portions of features being imaged in a current swath of the imaging head.

Abstract: A multi-channel imaging head is calibrated in accordance with a pre-determined regular pattern to minimize swath-to-swath and inter-swath variations during the imaging of the regular pattern. The imaging parameters of the imaging head are optimized in accordance with the pre-determined regular pattern.

Abstract: Methods for imaging patterns of features by thermal transfer involve controlling intensities of a plurality of beams. The intensities of beams that image edge portions of a feature may be set to be different from the intensities of beams that image interior portions of the feature. Beams that image home and away edges of a feature may be controlled to have different intensities. Apparatus for imaging patterns of features may comprise a controller configured to maintain intensity information for channels of a multi-channel imaging head. The controller uses the intensity information to set intensities of those channels that correspond to edge portions of features being imaged in a current swath of the imaging head.

Abstract: A multi-channel imaging head is calibrated in accordance with a pre-determined regular pattern to minimize swath-to-swath and inter-swath variations during the imaging of the regular pattern. The imaging parameters of the imaging head are optimized in accordance with the pre-determined regular pattern.

Abstract: An optical cross-connect switch is disclosed for switching optical communication signals between any of a plurality of input optical channels and any of a plurality of output optical channels. The switch comprises a first pattern projector configured to project one or more first control signal radiation patterns and a plurality of output encoders. Each output encoder is associated with one of the plurality of output optical channels. Each output encoder is positioned, relative to its associated output optical channel and the first pattern projector, to receive the first control signal radiation patterns and to detect at least a portion of one or more corresponding output Moiré interference patterns produced by the control signal radiation patterns. Each output encoder is configured to generate a corresponding output control signal indicative of an intensity of detected output Moiré interference patterns.

Abstract: A method and apparatus are disclosed for an optical fiber cross-connect switch incorporating an absolute position encoder and a magnetic actuation system into its alignment system. The switch comprises two optically opposed arrays of fiber-optic switching units, each of which contains a single fiber active to send or receive an optical communication signal. The magnetic actuation system comprising four magnetically polarizable actuator branches positioned surrounding the fiber and a magnetizable disk circumferentially attached to the fiber end. Selective magnetic polarization of the actuator branches bends the fiber end. A two-dimensional Moiré type position encoder determines the absolute position of the fiber end. The encoder comprises at east one plurality of radiation sources, which emits pulses of radiation (control signals) directed toward the switching units.

Abstract: An optical cross-connect switch is disclosed for switching optical communication signals between any of a plurality of input optical channels and any of a plurality of output optical channels. The switch comprises a first pattern projector configured to project one or more first control signal radiation patterns and a plurality of output encoders. Each output encoder is associated with one of the plurality of output optical channels. Each output encoder is positioned, relative to its associated output optical channel and the first pattern projector, to receive the first control signal radiation patterns and to detect at least a portion of one or more corresponding output Moiré interference patterns produced by the control signal radiation patterns. Each output encoder is configured to generate a corresponding output control signal indicative of an intensity of detected output Moiré interference patterns.

Abstract: A method and apparatus are disclosed for a two-dimensional Moiré type absolute position encoder and an associated control system. A reticle having a pattern variation in two orthogonal directions is illuminated with radiation from a source which is structured so as to create a two dimensional Moiré interference at the reticle. Radiation pulses from the radiation source are multiplexed in time and the resulting interference fringes are converted into electronic signals using a detector. A controller uses the electrical signals to determine the absolute position of the reticle in two dimensions to within the area of a particular cell. After determining the particular cell location, the controller also employs the signals from the groups of radiation stripes to calculate an accurate position of the reticle within the cell.

Abstract: A method and apparatus are disclosed for a two-dimensional Moiré type absolute position encoder and an associated control system. A reticle having a pattern variation in two orthogonal directions is illuminated with radiation from a source which is structured so as to create a two dimensional Moire interference at the reticle.

Abstract: A method and apparatus are disclosed for an optical fiber cross-connect switch incorporating an absolute position encoder and a magnetic actuation system into its alignment system. The switch comprises two optically opposed arrays of fiber-optic switching units, each of which contains a single fiber active to send or receive an optical communication signal. The magnetic actuation system comprising four magnetically polarizable actuator branches positioned surrounding the fiber and a magnetizable disk circumferentially attached to the fiber end. Selective magnetic polarization of the actuator branches bends the fiber end. A two-dimensional Moir{acute over (e )} type position encoder determines the absolute position of the fiber end. The encoder comprises at east one plurality of radiation sources, which emits pulses of radiation (control signals) directed toward the switching units.