Abstract: A method for forming planar-waveguide Bragg grating in a curved waveguide comprises: forming a long chirped planar-waveguide Bragg grating in an Archimedes' spiral such that a long length of the waveguide can fit in a small chip area where the grating is formed in the curved waveguide; using periodic width modulation to form the planar-waveguide Bragg grating on the curved waveguide, and where the formation of the periodic width modulation occurs during the etching of the waveguide core; using rectangular width modulation to create Bragg gratings with a higher order than 1st order to allow a larger grating period and larger modulation depth, using waveguide width tapering while keeping the width modulation period constant to introduce chirp to the planar-waveguide Bragg grating where the index of refraction is a function of waveguide width, by applying a specific width tapering to create a desired arbitrary chirp profile.

Abstract: A solid-state thermal neutron detector comprises: a layered structure that includes; an electrically insulating substrate; a first electrode affixed to the substrate; a neutron-reactive layer affixed to and in ohmic contact with the first electrode; and a second electrode affixed to and in ohmic contact with the neutron-reactive layer; a voltage source electrically coupled to the first and second electrodes; and an electrical current detector electrically coupled in series between the layered structure and the voltage source.

Abstract: A resonant driving circuit for a laser diode comprises an impulse generator for generating narrow output pulses, a delay line for generating a composite output of reflections of the output pulses from terminations of the transmission line, a laser diode for generating an optical output from the composite output, and a forward bias network to bias the laser diode.

Abstract: A method of encoding a digital image using adaptive partitioning in an iterated transformation image compression system is provided. A set of ranges R is initialized to include at least two uncovered ranges. A set of domains D is initialized to include only one member which is the entire image area.For each uncovered range in the set R: A transformation is generated for each domain in the set of domains. Each domain is transformed into corresponding transformed images to map onto each uncovered range in the set R. Each domain's transformation is optimized and is indicative of a domain's corresponding optimized transformation image for an associated uncovered range. Each optimized transformation image is compared with the associated uncovered range to provide error data as a function of the difference therebetween. The associated uncovered range is redefined as a covered range when the error data for the associated uncovered range is within predefined limits.

Abstract: A method is provided for encoding an image in an iterated transformation image compression system. The image, represented by an array of pixels, is partitioned into ranges and domains. A transformation is generated for each domain such that no transformation is constrained to be contractive. Each domain's transformation is optimized in terms of the intensity scaling and offset coefficients. A domain and corresponding optimized transformation is selected that minimizes transformation error data. These steps are repeated for a chosen plurality of the ranges that form a non-overlapping tiling of the image and such that the corresponding optimized transformations associated with the chosen plurality form an eventually contractive map. Information that identifies each of the chosen plurality of the ranges and the selected domains and corresponding optimized transformations is then stored in an addressable memory as an encoding of the image.