Abstract: Adjustment of a tunable external-cavity laser is simplified by incorporating a mount that includes a base, a main body, a reflecting surface, a diffracting surface and a hinge coupling the main body to the base. The laser additionally includes a light source, a converging lens located to receive light from the light source, a tuning mirror and a pivoting arm on which the tuning mirror is mounted. The main body is bounded in part by two plane, external surfaces orthogonal to a common reference plane and angularly separated from one another by an angle. The reflecting surface has a spatial orientation defined by one of the external surfaces and is arranged to receive light from the lens. The diffracting surface has a spatial orientation defined by the other of the external surfaces, and diffracts light received from the reflecting surface towards the tuning mirror. The hinge is located opposite the angle and parallel to the reference plane.

Abstract: An imager captures successive images of an object. One image is then subtracted from another image to generate difference images. Each difference image is then correlated with itself or with one of the images used to generate the difference image to determine the relative motion between the imager an the object.

Abstract: An apparatus and method for measuring displacement includes a light beam directed to an interferometer core that splits the light beam into first and second component beams. The first component beam is directed to a diffraction grating at approximately a Littrow angle. A diffraction is received by the interferometer core and is combined with the second component beam. The combination of the first and second component beams is measured to determine displacement of the diffraction grating.

Abstract: Wavelength tunable light sources and methods of operating the same are described. In one aspect, a wavelength tunable light source includes a resonant light path, an optical gain medium, an optical grating, a first acousto-optic deflector, and a second acousto-optic deflector. In another aspect, a light source has a resonant light path containing first and second acousto-optic devices for tuning an output light beam over a specified frequency range with an output wavelength profile. The first acousto-optic device is driven with a first signal having a first time-varying frequency profile. The second acousto-optic device is driven with a second signal having a second time-varying frequency profile, wherein the second time-varying frequency profile differs from the first time-varying frequency profile by an amount substantially proportional to a time rate is of change of the output wavelength profile.

Abstract: Adjustment of a tunable external-cavity laser is simplified by incorporating a mount that includes a base, a main body, a reflecting surface, a diffracting surface and a hinge coupling the main body to the base. The laser additionally includes a light source, a converging lens located to receive light from the light source, a tuning mirror and a pivoting arm on which the tuning mirror is mounted. The main body is bounded in part by two plane, external surfaces orthogonal to a common reference plane and angularly separated from one another by an angle. The reflecting surface has a spatial orientation defined by one of the external surfaces and is arranged to receive light from the lens. The diffracting surface has a spatial orientation defined by the other of the external surfaces, and diffracts light received from the reflecting surface towards the tuning mirror. The hinge is located opposite the angle and parallel to the reference plane.

Abstract: A method for synchronously tuning a laser in a laser system having a set of possible resonant frequencies including a resonating mode resonant frequency, an optical amplifier with an optical gain and a mode filter having a center frequency includes the steps of determining the optical gain of the optical amplifier and providing an optical gain signal representative of the optical gain. An apparatus for synchronously tuning a laser in a laser system has a set of possible resonant frequencies including a resonating mode resonant frequency and a mode filter having a pass band with a center frequency. The apparatus has an optical amplifier having an optical gain and a frequency shifter. The frequency shifter shifts the center frequency of the pass band in accordance with the optical gain to move the center frequency of the pass band toward the resonating mode resonant frequency.

Abstract: An imager captures successive images of an object. One image is then subtracted from another image to generate difference images. Each difference image is then correlated with itself or with one of the images used to generate the difference image to determine the relative motion between the imager an the object.

Abstract: Adjustment of a tunable external-cavity laser is simplified by incorporating a mount that includes a base, a main body, a reflecting surface, a diffracting surface and a hinge coupling the main body to the base. The laser additionally includes a light source, a converging lens located to receive light from the light source, a tuning mirror and a pivoting arm on which the tuning mirror is mounted. The main body is bounded in part by two plane, external surfaces orthogonal to a common reference plane and angularly separated from one another by an angle. The reflecting surface has a spatial orientation defined by one of the external surfaces and is arranged to receive light from the lens. The diffracting surface has a spatial orientation defined by the other of the external surfaces, and diffracts light received from the reflecting surface towards the tuning mirror. The hinge is located opposite the angle and parallel to the reference plane.

Abstract: Frequency-tunable light sources and methods of generating frequency-tunable light are described. In one aspect, a frequency-tunable light source includes a resonant optical cavity, an optical gain medium, an optical mode filter, and a mode frequency tuner. The resonant optical cavity supports oscillation of light in at least one longitudinal mode having a respective mode frequency. The optical gain medium is disposed in the resonant optical cavity and is operable to amplify light. The optical mode filter is arranged to intercept light oscillating in the resonant optical cavity and has an optical transmission pass-band with a tunable center frequency. The mode frequency tuner is arranged to intercept light oscillating in the resonant optical cavity and is operable to tunably change the mode frequencies of the at least one longitudinal mode of the resonant optical cavity. In another aspect, a resonant optical cavity is provided.

Abstract: Wavelength tunable light sources and methods of operating the same are described. In one aspect, a wavelength tunable light source includes a resonant light path, an optical gain medium, an optical grating, a first acousto-optic deflector, and a second acousto-optic deflector. In another aspect, a light source has a resonant light path containing first and second acousto-optic devices for tuning an output light beam over a specified frequency range with an output wavelength profile. The first acousto-optic device is driven with a first signal having a first time-varying frequency profile. The second acousto-optic device is driven with a second signal having a second time-varying frequency profile, wherein the second time-varying frequency profile differs from the first time-varying frequency profile by an amount substantially proportional to a time rate is of change of the output wavelength profile.

Abstract: The present invention relates to a structure comprising a biological membrane and a porous or perforated substrate, a biological membrane, a substrate, a high throughput screen, methods for production of the structure membrane and substrate, and a method for screening a large number of test compounds in a short period. More particularly it relates to a structure comprising a biological membrane adhered to a porous or perforated substrate, a biological membrane capable of adhering with high resistance seals to a substrate such as perforated glass and the ability to form sheets having predominantly an ion channel or transporter of interest, a high throughput screen for determining the effect of test compounds on ion channel or transporter activity, methods for manufacture of the structure, membrane and substrate, and a method for monitoring ion channel or transporter activity in a membrane.

Abstract: Systems and methods for adjusting optical path length of an optical path are provided. The systems and methods can be used to controllably adjust optical path length in an external cavity laser. A representative optical path having a first end and a second end comprises a first transparent refractive element located in the optical path between the first end and the second end. The transparent refractive element is adjustable to adjust the optical path length of the optical path without changing the physical distance between the first end and the second end. A representative method includes introducing a transparent refractive element into the optical path and adjusting the transparent refractive element to change the optical path length without changing the physical distance between the first end and the second end of the optical path.

Abstract: Adjustment of a tunable external-cavity laser is simplified by incorporating a mount that includes a base, a main body, a reflecting surface, a diffracting surface and a hinge coupling the main body to the base. The laser additionally includes a light source, a converging lens located to receive light from the light source, a tuning mirror and a pivoting arm on which the tuning mirror is mounted. The main body is bounded in part by two plane, external surfaces orthogonal to a common reference plane and angularly separated from one another by an angle. The reflecting surface has a spatial orientation defined by one of the external surfaces and is arranged to receive light from the lens. The diffracting surface has a spatial orientation defined by the other of the external surfaces, and diffracts light received from the reflecting surface towards the tuning mirror. The hinge is located opposite the angle and parallel to the reference plane.

Abstract: Systems and methods for adjusting optical path length of an optical path are provided. The systems and methods can be used to controllably adjust optical path length in an external cavity laser. A representative optical path having a first end and a second end comprises a first transparent refractive element located in the optical path between the first end and the second end. The transparent refractive element is adjustable to adjust the optical path length of the optical path without changing the physical distance between the first end and the second end. A representative method includes introducing a transparent refractive element into the optical path and adjusting the transparent refractive element to change the optical path length without changing the physical distance between the first end and the second end of the optical path.

Abstract: An optical projection system that combines a lenslet array and lightvalve with an active color filter. The active color filter may be placed at either the illuminating aperture plane or at any position conjugate or incident to the output plane of the projection lens of the system.

Abstract: A novel development of the conventional patch clamp technique for measurement of whole cell electrical activity provides for cells to be suspended in a liquid medium at a liquid/air interface (by virtue of the effect of surface tension at the interface) whereby cells are accessible at the interface to a microstructure electrode (such as a pipette tip (3)) to which a cell can attach to form an electrical seal, for the purpose of whole cell voltage clamp recording. The electrode forms a high resistance electrical seal with a cell suspended at the interface without the need to press the cell against a solid support surface. The step of bringing the electrode into contact with the interface is achieved not by relative movement, but by applying a differential pressure across the interface to cause the meniscus to be lowered and so to “bulge” (16) towards and into contact with the electrode.

Abstract: A method and apparatus for obtaining a patch-clamp recording from a cell, including providing a microchannel for axial flow of a liquid, providing at least one access port to allow radial access to the interior of the microchannel whereby liquid in the microchannel forms a meniscus at the port and produces an air/liquid interface, providing a patch-clamp pipette having a tip suitable for passing into the access port to form a high-resistance electrical seal between the tip and the cell, passing liquid carrying the cell axially along the microchannel, causing the cell to be carried to the access port, moving the patch-clamp pipette tip and the microchannel relative to each other radially to bring the tip into contact with the air/liquid interface in the access port, and applying suction to the patch-clamp to draw the cell onto the tip to form the seal.

Abstract: An optical projection system that combines a lenslet array and lightvalve with an active color filter. The active color filter may be placed at either the illuminating aperture plane or at any position conjugate or incident to the output plane of the projection lens of the system.

Abstract: A ferroelectric liquid crystal-based light valve system with contrast control and a method for controlling contrast in a ferroelectric liquid crystal-based light valve system. The light valve system includes a light input, a ferroelectric liquid crystal-based spatial light modulator, an analyzer, and a voltage controller. The ferroelectric liquid crystal-based spatial light modulator includes signal processing electronics and an array of pixels. The array of pixels is configured to receive light from the light input and includes an array of pixel electrodes, a transparent electrode, and a layer of ferroelectric liquid crystal material. Each pixel electrode is independently switchable between a first voltage level and a second voltage level by the signal processing electronics. One of these levels may be a variable input voltage level. The analyzer has orthogonal directions of maximum transmissivity and minimum transmissivity.

Abstract: An optical projection system that combines a lenslet array and lightvalve with an active color filter. The active color filter may be placed at either the illuminating aperture plane or at any position conjugate or incident to the output of the projection lens of the system.