Abstract: A method and apparatus for dynamically controlling variation in an attribute of a light beam employing materials with unusually high electrooptical coefficients that are subject to optical damage from the light beam being controlled. The method includes providing a transmission medium composed of a high sensitivity electrooptic material transparent to the light beam and having a nonzero electrooptic coefficient, where the medium is adapted to receive, propagate, and output the light beam. The medium is subjected to an electric field, the strength of which is controlled to determine the amount of variation of the light beam attribute. The field is generated by electrodes appropriately enclosing the medium and inducing a voltage across the electrodes. The medium is illuminated by a suppressing light source, the illumination being intense enough to significantly reduce charge distribution inhomogeneity within the medium.

Abstract: A light beam deflector comprises an initial beam deflector that imparts a small initial deflection, and a beam deflection amplifier that increases the initial small deflection by a multiplication factor. The first of two initial beam deflector embodiments employs highly-electro-optic-sensitive materials and provides methods for reducing and eliminating their photorefractive effects, including the use of a suppressing light source, external electric fields, and temperature control. The second embodiment employs a multi-layer, iterative prism structure, increasing the aperture without increasing the supply voltage. The first of five embodiments of the beam deflection amplifier is a Keplerian telescope lens first stage and a negative lens system second stage. The second is a Galilean telescope lens first stage and a negative lens system second stage. The third is either a Keplerian or Galilean telescope lens alone. The fourth replaces the single second lens of the first stage with a compound lens system.

Abstract: An optical switching system employing switching modules. Each module comprises (a) a source channel, (b) a transmitting element, (c) a receiving element, and (d) a destination channel. The transmitting element directs the source channel signal to a destination channel. The transmitting element includes an initial beam deflector and a beam deflection amplifier. The receiving element includes a beam deflection compressor and a beam aligner. One embodiment of the initial deflector is a pair of focusing lenses, one of which is displaced by a piezoelectric actuator. When one lens is displaced a distance d, the output light beam has a deflection angle &agr;=(f1+f2)/f2. The beam deflection amplifier multiplies the small angle &agr; by a transfer function F to result in a beam with a deflection angle F&agr;. The receiving element is the transmitting element in reverse. The first system configuration connects a single channel to one of a number of channels.

Abstract: An apparatus and method for wirelessly determining position and orientation of a first object relative to a second object in six dimensions, including one or more recording assemblies and one or more identification-coded or orientation-coded optical transponders. The positions of the recording assemblies are fixed relative to the first object and the transponders are fixed relative to the second object. A light source in each recording assembly emits light into space that is received, modulated, and retransmitted back by each transponder to a photodetector assembly in the recording assembly. The identification-coded optical transponder modulates the retransmitted light with a unique fixed code. The orientation-coded optical transponder modulates the retransmitted light with a unique fixed code that depends upon the direction of the incident light.

Abstract: A light beam deflector comprises an initial beam deflector that imparts a small initial deflection, and a beam deflection amplifier that increases the initial small deflection by a multiplication factor. There are five embodiments of the initial beam deflector. The first four use a pair of lenses and a piezoelectric actuator affixed to one lens. When the parallel lens axes are separated by a distance, the incident light beam will be deflected by a small angle, typically up to about 5°. The fifth embodiment comprises a mirror affixed to a piezoelectric actuator, which tilts the mirror. The beam deflection amplifier has five embodiments. The first is a Keplerian telescope lens first stage and a negative lens system second stage. The first is a Galilean telescope lens first stage and a negative lens system second stage. The third embodiment is either a Keplerian or Galilean telescope lens alone. The fourth embodiment replaces the single second lens of the first stage with a compound lens system.

Abstract: A light beam deflector comprising an initial dynamic beam deflector and a beam deflection amplifier. The initial deflector can be any currently available device for providing a small angle deflection. The beam deflection amplifier has two embodiments: a Keplerian telescope lens first stage and a negative lens system second stage, and a Galilean telescope lens first stage and a negative lens system second stage.

Abstract: An apparatus for extending the light deflection angle, so a light beam can be dynamically controlled within ±90°, pitch and yaw. The device comprises an initial dynamic beam deflector and a compound light beam direction mapper. The beam direction mapper includes a beam size reducer, a beam transmission adapter, and a projector. An initial light beam from a light source is deflected a small amount by the initial dynamic beam deflector. The initially deflected light beam is focused by the beam size reducer to a light energy spot on the beam transmission adapter, which transfers the light spot to the projector. The projector emits an output light beam at the far field of its output space with an output deflection angle larger than the initial deflection angle. All components are based on classical geometry optics and the energy of the output light beam is within an order of magnitude of that of the input light beam.

Abstract: A method for performing dual-energy x-ray imaging of a human breast including separating the breast image into five basic first order approximation image components: a dual-energy scatter image pair, a lean tissue image, a fat tissue image, and a microcalcification image. In the second order approximation, lean tissue image and fat tissue image are adjusted to correct for the microcalcification component so that each contains only a single breast component. The method also includes a calibration method so that the materials used are the actual breast tissues, instead of merely equivalent materials.

Abstract: An apparatus and method for removing scatter from x-ray images acquired by two-dimensional digital detectors. The apparatus consists of, in physical order, an x-ray source, a front two-dimensional x-ray detector, a beam selector, and a rear two-dimensional x-ray detector. The subject is located between the x-ray source and front detector. There two types of beam selectors, one allowing only primary x-rays to reach selected locations of the rear detector, and the other allowing primary x-rays and scatter to reach selected locations of the rear detector while allowing only scatter x-rays to reach shadowed locations of the rear detector. The method includes determining a low-resolution primary x-ray rear detector image, calculating an approximate low-resolution primary x-ray front detector image, calculating a high-resolution primary image at the front detector, and applying one or more of several correction procedures for achieving higher accuracy from the approximations.

Abstract: A retroreflecting modulator including a lens, a light guide, a light modulator, and a reflective surface. Incident light falls on the lens, where it is focused as a spot on a focal surface. The light guide transmits the focused light to the light modulator, where it is modulated and reflected back, via the reflective surface and light guide, to the lens. The lens emits the modulated light in the opposite direction as the incident light. The preferred light-receiving and focusing device is a specialty sphere lens, the preferred light guide is a fiber optic plate, and the preferred light modulator is a liquid crystal modulator. The retroreflecting modulator may be spatially-unresolvable, where a single signal modulates the light, or spatially-resolvable, where the modulation signal depends upon the direction of the incident light.

Abstract: Apparatus and method for performing dual-energy x-ray imaging using two-dimensional detectors. The apparatus consists of, in physical order, an x-ray source, a front two-dimensional x-ray detector, a beam selector, and a rear two-dimensional x-ray detector. The subject is located between the x-ray source and front detector. The beam selector prevents primary x-rays from reaching selected locations of the rear detector. A pair of primary dual-energy images is obtained at the rear detector. Using a dual-energy data decomposition method, a low-resolution primary x-ray front detector image is calculated, from which a high-resolution primary dual-energy image pair is calculated. In addition, the data decomposition method can be used to calculate a pair of high-spatial-resolution material composition images.

Abstract: Apparatus and method for eliminating scatter effects in x-ray imaging using two-dimensional detector arrays. The apparatus consists of, in physical order, an x-ray source, a front two-dimensional x-ray detector, a beam selector, and a rear two-dimensional x-ray detector. The subject is located between the x-ray source and front detector. The beam selector prevents scatter x-rays from reaching the rear detector. The method simultaneously solves the two interdependent problems of obtaining scatter-free x-ray images and conducting dual-energy x-ray imaging with primary x-ray data. A high-resolution composite image containing primary and scatter x-ray components is read from the front detector. A low-resolution composite image is produced from the high-resolution composite image. A pair of low-resolution primary x-ray dual-energy images is read from the rear detector. Using an improved dual-energy data decomposition method, a low-resolution primary x-ray front detector image is calculated.

Abstract: An apparatus, for producing scatter-free two-dimensional X-ray images and eliminating scattering effects on integrated detector arrays, includes, in physical sequence from front to back, an X-ray source, a front two-dimensional detector positioned behind a subject for detecting both primary and scatter X-rays produced from striking the subject with the source's radiation, a collimator with holes for passing a portion of the primary X-rays, and a rear two-dimensional detector for receiving this portion. A method for producing scatter-free images which includes the steps of; X-raying the subject with high and low energy, retrieving an image pair I.sub.rHl and I.sub.rLl from the rear detector, normalizing and subtracting dark signals from I.sub.rHl and I.sub.rLl to yield an image pair D.sub.rHl and D.sub.rLl, solving D.sub.rHl and D.sub.rLl to determine b and s, retrieving an image I.sub.fh from the front detector, normalizing and subtracting dark signals from I.sub.fh to yield D.sub.

Abstract: Fluorescence immunoassay for determining single or multiple analytes based upon a single measurement of fluorescence are described.

Abstract: A method and apparatus for time-resolved fluorescence spectroscopy is described in which laser light from a single pulse is used to excite fluorescent photons in a sample, which fluorescence is detected by a PMT optimized for linearity and response time to produce photoelectrons which generate a current at the PMT anode. This current is discharged through an R/C network to produce a voltage amplitude waveform which is converted to an optical image, intensified, stored and digitized. The digitized version of the optical image is processed in a data processor to calculate the true fluorescence impulse response.