Abstract: A method for decreasing scatter or crosstalk in holographic elements recorded in self-developing media, comprising exposing a photopolymer recording media to a holographic pattern at a first temperature of said photopolymer recording media, wherein monomer diffusion is substantially reduced at said first temperature, and warming said photopolymer recording media to a second temperature wherein monomer diffusion is enabled.

Abstract: A near-eye display system that employs a volume holographic element containing distinct but overlapped planar volume gratings, each corresponding to a subset of pixels in the display. The volume gratings are illuminated using light incident from angles, and at wavelengths, that match the conical diffraction conditions for each grating, thereby achieving both high diffraction efficiency and a wide field of view. A single volume grating can thus be used to display thousands of pixels independently with high efficiency.

Abstract: An image display device, including a light-emitting pixel array operable to emit a plurality of two-dimensional images each comprising a plurality of pixels; a light field converter comprising a coherent optical fiber plate including a plurality of optical fibers, wherein the optical fiber plate has a first surface and a second surface, and an array of lenslets arranged along the second surface, wherein the array of lenslets is configured to have a focal surface conforming to the second surface of the optical fiber plate; wherein the light field converter is operable to transform pixels from each of the plurality of two-dimensional images into corresponding diverging rays; wherein the diverging rays form virtual three-dimensional image in an image-forming region.

Abstract: Methods and systems for projecting wave fields use a diffusing medium, a wavefront shaper, an illumination source, and a control system. A system for projecting an object wave field into a projection volume includes a wave scatterer, a wave field projector configured to project a wave field onto the wave scatterer, and a controller coupled to the wave field projector. The controller is configured to cause the wave field projector to project a wave field that, upon interacting with the wave scatterer, is redirected to form an object wave field that forms a predetermined pattern in the projection volume.

Abstract: Methods and systems for projecting wave fields use a diffusing medium, a wavefront shaper, an illumination source, and a control system. A system for projecting an object wave field into a projection volume includes a wave scatterer, a wave field projector configured to project a wave field onto the wave scatterer, and a controller coupled to the wave field projector. The controller is configured to cause the wave field projector to project a wave field that, upon interacting with the wave scatterer, is redirected to form an object wave field that forms a predetermined pattern in the projection volume.

Abstract: Methods and systems for projecting wave fields use a diffusing medium, a wavefront shaper, an illumination source, and a control system. A system for projecting an object wave field into a projection volume includes a wave scatterer, a wave field projector configured to project a wave field onto the wave scatterer, and a controller coupled to the wave field projector. The controller is configured to cause the wave field projector to project a wave field that, upon interacting with the wave scatterer, is redirected to form an object wave field that forms a predetermined pattern in the projection volume.

Abstract: Methods and systems for projecting wave fields use a diffusing medium, a wavefront shaper, an illumination source, and a control system. A system for projecting an object wave field into a projection volume includes a wave scatterer, a wave field projector configured to project a wave field onto the wave scatterer, and a controller coupled to the wave field projector. The controller is configured to cause the wave field projector to project a wave field that, upon interacting with the wave scatterer, is redirected to form an object wave field that forms a predetermined pattern in the projection volume.

Abstract: An assay system includes an optical imager to acquire high resolution images of assay strips (e.g., lateral flow immunochromatographic test strips) and performs image processing to identify individual assay strips and determine results for each assay strip, by quantifies the presence or absence of test signal line(s) and control signal line(s). Assay strips may be in a holder or carrier contained in a specimen container also holding a specimen. The assay system automatically logs all results and data to a database that stores a high resolution image of the original immunochromatographic assay, the values of test line(s) and control line(s), and the test result. A user interface directs an end user through operation.

Abstract: An assay system includes an optical imager to acquire high resolution images of assay strips (e.g., lateral flow immunochromatographic test strips) and performs image processing to identify individual assay strips and determine results for each assay strip, by quantifies the presence or absence of test signal line(s) and control signal line(s). Assay strips may be in a holder or carrier contained in a specimen container also holding a specimen. The assay system automatically logs all results and data to a database that stores a high resolution image of the original immunochromatographic assay, the values of test line(s) and control line(s), and the test result. A user interface directs an end user through operation.

Abstract: An assay system includes an optical imager to acquire high resolution images of assay strips (e.g., lateral flow immunochromatographic test strips) and performs image processing to identify individual assay strips and determine results for each assay strip, by quantifies the presence or absence of test signal line(s) and control signal line(s). Assay strips may be in a holder or carrier contained in a specimen container also holding a specimen. The assay system automatically logs all results and data to a database that stores a high resolution image of the original immunochromatographic assay, the values of test line(s) and control line(s), and the test result. A user interface directs an end user through operation.

Abstract: A retro-emissive marking system that returns a coded-spectrum optical signal to a source of an interrogation beam is described. The system is valuable for applications such track-and-trace systems, vehicle markings, anti-counterfeit/security, inventory control, animal ear tags, product authentication, identification cards, and security systems; and it also has value as a remotely readable sensor of chemical or biological agents.

Abstract: The invention relates to an anticounterfeiting device comprising a form birefringent surface relief structure bearing a colored three-dimensional polarization image. The structure may be composed of pixels whose surface relief microstructure and composition determines the direction and color of zero-order diffracted light visible from each pixel when the structure is illuminated with polarized light and viewed through an analyzer that passes light of the opposite polarization.

Abstract: Quantum resonance fluorescent microscope systems for detecting component substances in a specimen are described. The systems are based on exciting the sample containing the material with a femtosecond to nanosecond probe pulse of collimated light, which is tailored to optimize detection of a given material by separating the probe pulse into component features of frequency, polarization, phase and/or amplitude. The component features are independently shaped and formed into a composite pulse selected to optimize a signature response pulse received from the material. In some cases, two independently re-shaped pulses are combined, where one re-shaped pulse has two mixed polarization states and the other re-shaped pulse is linearly polarized. These two pulses are made to intersect at an angle of 90 degrees so that the combined pulse has electric field in each of the XYZ axes.

Abstract: An anticounterfeiting device comprising a surface relief structure having both diffractive and polarizing properties. Polarization of reflected light is controlled by the orientation and composition of a fine grating structure whose shortest period is substantially smaller than the wavelength of visible light; and diffraction is controlled by a longer period component of the grating structure having a second orientation. Presence and arrangement of the polarizing properties of the device are detected by illuminating the device with polarized light and viewing the reflected light, or by illuminating the device with unpolarized light and viewing reflected light through a polarizer. Because such a device is difficult to copy or reverse engineer precisely, the authenticity of the device can be judged by the presence and arrangement of the polarization properties and the diffraction properties in the device.

Abstract: Quantum based systems for detecting materials in a sample, including biological, chemical and physical materials are described. The systems are based on exciting the sample containing the material with a femtosecond to nanosecond probe pulse of collimated light, which is tailored to optimize detection of a given material by separating the probe pulse into component features of frequency, polarization, phase and/or amplitude. The component features are independently shaped and formed into a composite pulse selected to optimize a signature response pulse received from the material.

Abstract: A system and method for reading the information stored in holograms and other diffractive objects. The information is read by analyzing the diffraction pattern produced when a laser beam is focused onto a small spot on the object and scanned across the object.

Abstract: An anticounterfeiting device comprising a surface relief structure having both diffractive and polarizing properties. Polarization of reflected light is controlled by the orientation and composition of a fine grating structure whose shortest period is substantially smaller than the wavelength of visible light; and diffraction is controlled by a longer period component of the grating structure having a second orientation. Presence and arrangement of the polarizing properties of the device are detected by illuminating the device with polarized light and viewing the reflected light, or by illuminating the device with unpolarized light and viewing reflected light through a polarizer. Because such a device is difficult to copy or reverse engineer precisely, the authenticity of the device can be judged by the presence and arrangement of the polarization properties and the diffraction properties in the device.

Abstract: Quantum dots are used as fluorescent taggants in security inks, papers, plastics, explosives, or any other item or substance in which it is desired to provide a distinct signature or marking. Quantum dots of specific sizes, compositions and structures may be used to produce specific fluorescence, mixtures of quantum dots can be used to produce random patterns of spectrally varying fluorescence, and particular quantum dot structures can be used to provide desirable physical and optical properties. The quantum dots may be read with an optical reader, which may be combined with readers using other technologies.

Abstract: Counter-current heat flow systems are disclosed, where heat containing medium flows in adjacent conduits arranged anti-parallel to one another so that the medium flowing from a warm zone to a cool zone flows adjacent to the medium flowing from the cool to the warm zone in the opposite direction. A plurality of heat pumps are distributed along the conduits to actively pump heat between adjacent points of the conduits. Little energy is required to pump heat between the adjacent points yet a large temperature difference can be maintained between the warm and the cool zones. The heat containing medium can be a fluid or an electric current. The medium in one conduit may have a different heat capacity than the medium in the other conduit. A controller may be included to regulate the plurality of heat pumps and/or the flow of the media to maintain a desired temperature at the warm zone or the cool zone.

Abstract: Counter-current heat flow systems are disclosed, where heat containing medium flows in adjacent conduits arranged anti-parallel to one another so that the medium flowing from a warm zone to a cool zone flows adjacent to the medium flowing from the cool to the warm zone in the opposite direction. A plurality of heat pumps are distributed along the conduits to actively pump heat between adjacent points of the conduits. Little energy is required to pump heat between the adjacent points yet a large temperature difference can be maintained between the warm and the cool zones. The heat containing medium can be a fluid or an electric current. The medium in one conduit may have a different heat capacity than the medium in the other conduit. A controller may be included to regulate the plurality of heat pumps and/or the flow of the media to maintain a desired temperature at the warm zone or the cool zone.