Abstract: A system for transmitting power and data between two circuit boards may include a fixed circuit board having a primary coil and a rotatable circuit board having a secondary coil. The system may further include a sensor in communication with the secondary coil of the rotatable circuit board. The fixed circuit board's primary coil may be inductively coupled to the secondary coil and may provide power and receive data from the sensor when inductively coupled to the secondary coil.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Focus assemblies for laser radar are situated to receive a measurement beam that is focused at or in the focus assemblies. In some examples, focus assemblies include a corner cube and a return reflector, and the measurement beam is focused on, at, or within the corner cube or return reflector. A polarizing beam splitter and a quarter wave plate can be situated so that an input measurement beam and an output measurement beam can be separated.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Laser radar systems include a pentaprism configured to scan a measurement beam with respect to a target surface. A focusing optical assembly includes a corner cube that is used to adjust measurement beam focus. Target distance is estimated based on heterodyne frequencies between a return beam and a local oscillator beam. The local oscillator beam is configured to propagate to and from the focusing optical assembly before mixing with the return beam. In some examples, heterodyne frequencies are calibrated with respect to target distance using a Fabry-Perot interferometer having mirrors fixed to a lithium aluminosilicate glass-ceramic tube.

Abstract: Boresight and other pointing errors are detected based on a monitor beam formed by diverting a portion of a probe beam. The monitor beam is directed to a position sensitive photodetector, and the optical power received at the position sensitive photodetector is used to estimate or correct such pointing errors.

Abstract: An exemplary method involves, in a system comprising a tool that performs a task on a workpiece, a method for determining displacement of the workpiece relative to the tool. Respective displacements of loci of at least a region of the workpiece are mapped using a Goos-Hänchen-insensitive (GH-insensitive) displacement sensor to produce a first set of physical displacement data for the region. Also mapped are respective displacements, from the tool, of the loci using a GH sensitive sensor to produce a second set of optical displacement data for the region. Goodness of fit (GOF) is determined of the second set of data with the first set. According to the GOF, respective GH-correction (GHC) coefficients are determined for at least one locus of the region. When measuring displacement of the at least one locus in the region relative to the tool, the respective GHC coefficient is applied to the measured displacement to reduce an error that otherwise would be present in the measured displacement due to a GH effect.

Abstract: Fringe projection autofocus systems are provided with variable pitch diffraction gratings or multiple diffraction gratings so that a reference beam and a measurement beam propagate along a common path. Alternatively, an input beam can be directed to a diffraction grating so that the selected diffraction orders propagate along a common path. In some examples, distinct spectral bands are used for reference and measurement beams.

Abstract: A gas turbine engine is disclosed having a cooling passage that rotates with a turbine and is capable of providing cooling flow to the turbine. In one embodiment the cooling passage can receive cooling flow from an interior of a shaft of the gas turbine engine and increase the pressure of the cooling flow before delivering it to a location near a blade of the turbine. In one form the cooling passage can have an inducer section. In one form the cooling passage can have internal vanes useful in increasing the pressure of the cooling flow.

Abstract: Fringe patterns at first and second spatial frequencies are projected onto a work piece surface and a reference surface, respectively. An image of the projected fringe patterns is obtained and a measurement signal associated with work piece displacements and a reference signal are obtained based on the first and second spatial frequencies. The image of the projected fringe patterns can exhibit substantial or complete overlap of the fringe patterns at the first and second spatial frequencies, and the overlapping patterns can be separated based on the spatial frequencies. Fringe pattern shifts at one or both of the first and second spatial frequencies can be used to adjust a pattern transfer system to permit accurate pattern transfer.

Abstract: An exemplary method involves, in a system comprising a tool that performs a task on a workpiece, a method for determining displacement of the workpiece relative to the tool. Respective displacements of loci of at least a region of the workpiece are mapped using a Goos-Hänchen-insensitive (GH-insensitive) displacement sensor to produce a first set of physical displacement data for the region. Also mapped are respective displacements, from the tool, of the loci using a GH sensitive sensor to produce a second set of optical displacement data for the region. Goodness of fit (GOF) is determined of the second set of data with the first set. According to the GOF, respective GH-correction (GHC) coefficients are determined for at least one locus of the region. When measuring displacement of the at least one locus in the region relative to the tool, the respective GHC coefficient is applied to the measured displacement to reduce an error that otherwise would be present in the measured displacement due to a GH effect.

Abstract: An exemplary method involves, in a system comprising a tool that performs a task on a workpiece, a method for determining displacement of the workpiece relative to the tool. Respective displacements of loci of at least a region of the workpiece are mapped using a Goos-Hänchen-insensitive (GH-insensitive) displacement sensor to produce a first set of physical displacement data for the region. Also mapped are respective displacements, from the tool, of the loci using a GH sensitive sensor to produce a second set of optical displacement data for the region. Goodness of fit (GOF) is determined of the second set of data with the first set. According to the GOF, respective GH-correction (GHC) coefficients are determined for at least one locus of the region. When measuring displacement of the at least one locus in the region relative to the tool, the respective GHC coefficient is applied to the measured displacement to reduce an error that otherwise would be present in the measured displacement due to a GH effect.

Abstract: A way of predicting distribution of light in an illumination pupil, comprising: (a) identifying one or more component(s) of an illumination system having an illumination pupil, where the component(s) affect the distribution of light in the illumination pupil; (b) generating a point spread function that depends on the identified component(s) and has a functional relationship with the configurable settings of the illumination system; and (c) predicting the distribution of light in the illumination pupil using the point spread function.

Abstract: Boresight and other pointing errors are detected based on a monitor beam formed by diverting a portion of a probe beam. The monitor beam is directed to a position sensitive photodetector, and the optical power received at the position sensitive photodetector is used to estimate or correct such pointing errors.

Abstract: Focus assemblies for laser radar are situated to receive a measurement beam that is focused at or in the focus assemblies. In some examples, focus assemblies include a corner cube and a return reflector, and the measurement beam is focused on, at, or within the corner cube or return reflector. A polarizing beam splitter and a quarter wave plate can be situated so that an input measurement beam and an output measurement beam can be separated.

Abstract: Fringe projection autofocus systems are provided with variable pitch diffraction gratings or multiple diffraction gratings so that a reference beam and a measurement beam propagate along a common path. Alternatively, an input beam can be directed to a diffraction grating so that the selected diffraction orders propagate along a common path. In some examples, distinct spectral bands are used for reference and measurement beams.

Abstract: Fringe patterns at first and second spatial frequencies are projected onto a work piece surface and a reference surface, respectively. An image of the projected fringe patterns is obtained and a measurement signal associated with work piece displacements and a reference signal are obtained based on the first and second spatial frequencies. The image of the projected fringe patterns can exhibit substantial or complete overlap of the fringe patterns at the first and second spatial frequencies, and the overlapping patterns can be separated based on the spatial frequencies. Fringe pattern shifts at one or both of the first and second spatial frequencies can be used to adjust a pattern transfer system to permit accurate pattern transfer.

Abstract: A metrology system that uses a plurality of photo-detecting targets positioned on the objects to be assembled, a plurality of rotating photo-emitting heads, a master signal generator that generates a reference RF signal, and a signal processor that determines the position of each of the targets from signals generated by each target in response to the photo-emitting heads. During operation, the reference RF signal is broadcast to the rotating photo-emitting heads and the photo-detecting targets. The RF signal is used to determine the azimuth of the heads relative to a zero reference position to a high degree of accuracy.