Abstract: A three-dimensional optical memory based on stacked thin film electron trapping layers. Each thin film electron trapping layer is sandwiched between pairs of insulating layers and transparent electrodes. When an electric field is applied across the electron trapping layer via the electrodes, the electron trapping process is enhanced. In this way, electrical page addressing can be achieved for writing data to the memory. The data are read out by an IR light directed into the electron trapping film from the edge, again preferably with the application of an electric field across the addressed layer to enhance readout. The application of an electric field across an addressed layer during the writing and reading steps effectively eliminates inter-page crosstalk.

Abstract: A vector-matrix multiplier in which a matrix is stored in an electron trapping material by exposing the material to visible light passed through a liquid crystal device, which acts as a mask. The visible light raises electrons in the electron trapping material to a higher energy level at the exposed locations. Infrared light is then passed through the liquid crystal device to form an input vector, which is projected onto the electron trapping material. The infrared light releases electrons from the higher energy level, resulting in emission of a pattern of visible light. The emission of visible light from the electron trapping material forms an output representing the product of the input vector and the matrix.

Abstract: A three-dimensional optical memory system is disclosed which utilizes at least two layers of electron trapping media having different sensitivities to visible light coated on a substrate to store data in the form of light energy. Data is written onto the substrate, which may be in the form of a disk, which is contained in a light-tight contamination-free environment similar to a Winchester hard disk drive system, using at least two visible light laser beams having different wavelengths. Data is read from the disk using an infrared light laser beam. The at least two different data streams are separately detected. The system may be used as part of an optical disk drive system which is designed to fit within a standard mini or 51/4 inch disk drive form factor for personal computers.

Abstract: A method for using electron trapping materials to perform subtraction of images. One image is written onto a 2-dimensional screen of electron trapping material. A second image that has many of the elements of the first, but less than the total number of elements of the first, is erased from the electron trapping screen with infrared light. An exposure of the entire screen to infrared light results in luminescence output from those regions in which electrons remain trapped after the subtraction. Potential applications include machine inspection, image compression, etc. Images can be written on the screen of electron trapping material using energetic radiation or using short wavelength visible light.

Abstract: An erasable optical disk drive system is disclosed which utilizes an electron trapping media coated on the disk surface to store data in the form of light energy. Data is written onto the disk, which is contained in a light-tight contamination-free environment similar to a Winchester hard disk drive system, using a near infrared light laser beam. Data is read from the disk using a visible light laser beam. The entire optical disk drive system is designed to fit within a standard mini or 51/4 inch disk drive form factor for personal computers.

Abstract: A vector-matrix multiplier in which a matrix is stored in an electron trapping material by exposing the material to visible light passed through a liquid crystal device, which acts as a mask. The visible light raises electrons in the electron trapping material to a higher energy level at the exposed locations. Infrared light is then passed through the liquid crystal device to form an input vector, which is projected onto the electron trapping material. The infrared light releases electrons from the higher energy level, resulting in emission of a pattern of visible light. The emission of visible light from the electron trapping material forms an output representing the product of the input vector and the matrix.

Abstract: A high resolution photostimulable storage phosphor screen for breast imaging using X-rays. The phosphor material for storing the image, SrS;Ce,Sm, is appropriately milled to a fine powder and dispersed, using appropriate methods, with high particle packing density, on a supporting substrate. The coated substrate froms a planar imaging screen for mammography. The phosphor screen of the present invention can record high quality digital (as opposed to analog) images for diagnostic breast imaging.

Abstract: A photography and imaging system and method using electron trapping materials. An input image is formed on an imaging plate having a layer of the electron trapping material disposed thereon. Electrons of the electron trapping material are excited from a ground level to a trapping level in a density and spatial distribution corresponding to the input image. Upon the application of infrared light, the trapped electrons are released from the trapping level and fall to the ground level, emitting visible light in a pattern reproducing the original input image. The reproduced image is viewed, or captured and displayed. Color photography and imaging is obtained by layering a number of different electron trapping materials having different wavelength emissions. Infrared photography and imaging is obtained by uniformly charging the electron trapping material with visible light, and then exposing the charged material to an infrared image.

Abstract: Materials having thermoluminescent properties using a base material and three dopants and made from a process of mixing the parts together, heating the mixture to fuse together, grinding the mass into a fine powder, and reheating the powder. The resultant powder may be combined with a vehicle to form a paint. A fusible salt may be used in making the thermoluminescent material. The dopants are preferably La.sub.2 O.sub.3, Eu.sub.2 O.sub.3 and CeO.sub.2.

Abstract: A photoluminescent material used for detection of infrared light is prepared using a base material, first and second dopants, a carbonate of the base material, and a fusible salt. The base material is an alkaline earth metal sulfide such as calcium sulfide. Calcium carbonate is used to decrease phosphorescence after charging, whereas lithium fluoride is used to allow the material to be fused together. Samarium oxide and europium oxide are used as the first and second dopants for establishing a communication band and an electron trapping level, respectively. The photoluminescent material is made according to a process involving drying the material, heating the material in a graphite crucible to a fusing temperature in a dry inert atmosphere, grinding the material after cooling, and reheating the material to below the fusing temperature, but sufficiently high to repair the crystal surfaces. The material is then placed in a transparent binder and applied to a substrate.

Abstract: A fiber optic dosimeter in which an electron trapping material is coated onto a tip of an optical fiber. The tip is placed in a region where radiation is to be measured, and the opposite end of the optical fiber, from which radiation readings are measured, is placed in a location remote from the radiation source. When radiation impinges upon the electron trapping material, electrons in the material are raised to a higher state where they are trapped and stay indefinitely. When infrared light strikes the material, the stored electrons are released from their traps and, upon falling to a lower energy level, emit visible light which can be detected and measured. Thus, to measure the amount of ambient radiation, the electron trapping material is stimulated with infrared light from an infrared source at the opposite end of the optical fiber.

Abstract: An imaging screen for detecting and storing information corresponding to the pattern of emission from an electrophoresis gel containing radioactively labelled, dye-tagged or chemiluminescent labelled DNA, RNA, or protein fragments. The imaging screen is coated with an electron trapping material which releasably stores energy from the impingement of the emission from the electrophoresis gel in the form of energy corresponding the pattern and flux of the emission. When subjected to optical energy of a first wavelength, the electron trapping material releases the stored energy in the form of optical energy of a second wavelength corresponding the flux and pattern of the emission from the electrophoresis gel. The released optical energy of a second wavelength is then detected and coverted to electrical signals representative of the flux and pattern of emission from the electrophoresis gel.

Abstract: An efficient energy upconversion unit is optically coupled to a photomultiplier. The upconversion unit receives incident infrared electromagnetic energy of longer wavelengths and emits, in response, visible light of shorter wavelengths to which the photomultiplier is more responsive. Through such energy upconversion, the sensitivity of the photomultiplier is extended to much longer infrared wavelengths. The upconversion unit is a photoluminescent material specially formulated to have minimal phosphorescence so as to minimize noise.

Abstract: An erasable optical disk drive system is disclosed which utilizes an electron trapping media coated on the disk surface to store data in the form of light energy. Data is written onto the disk, which is contained in a light-tight contamination-free environment similar to a Winchester hard disk drive system, using a near infrared light laser beam. Data is read from the disk using a visible light laser beam. The entire optical disk drive system is designed to fit within a standard mini or 51/4 inch disk drive form factor for personal computers.

Abstract: A photoluminescent material used for detection of infrared light is prepared using a base material, first and second dopants, a carbonate of the base material, and a fusible salt. The base material is an alkaline earth metal sulfide such as strontium sulfide. Strontium carbonate is used to decrease phosphorescence after charging, whereas lithium fluoride is used to allow the material to be fused together. Samarium oxide and europium oxide are used as the first and second dopants for establishing a communication band for luminescence and a trapping level, respectively. The photoluminescent material is made according to a process involving drying the material, heating the material in a graphite crucible to a fusing temperature in a dry inert atmosphere, grinding the material after cooling, and reheating the material to below the fusing temperature, but sufficiently high to repair the crystal surfaces. The material is then placed in a transparent binder and applied to a substrate.

Abstract: Photoluminescent materials useful for detection of infrared light are prepared using a base material, first and second dopants, barium sulfate and a fusible salt. The base material is an alkaline earth metal sulfide such as strontium sulfide, calcium sulfide, or a mixture of strontium sulfide and calcium sulfide. Barium sulfate is used to increase the brightness of output light, whereas lithium fluoride is used to allow the material to be fused together. Samarium, cerium and europium compounds are used in specific examples as dopants for providing electron traps. The photoluminescent material is made according to a process involving drying the mixture in a dry inert atmosphere, and heating the mixture in the inert atmosphere in a graphite crucible to a fusing temperature. The resultant material can then be applied to a substrate using thin film physical vapor deposition techniques.

Abstract: An improved method and apparatus for detecting and storing for later readout the impingement of certain nuclear particles utilizing a particle detector system having a large area particle detector including a thin or thick film of electron trapping material is disclosed, in which, upon impingement or detection of a nuclear particle, electrons contained in the electron trapping material jump to a higher energy level and a luminescence of a predetermined wavelength is given off by the large area particle detector. The detector may later be subjected to infrared or near-infrared pulsed radiation which will cause the release of photon luminescence of a predetermined wavelength at a position and intensity corresponding to the impinged particles, which can be detected by a suitable sensor and analyzed by a microcomputer. Particle detectors of area of at least 100 cm.sup.2 are disclosed.

Abstract: A method of photodynamic therapy employing an electron trapping material as the light source. The electron trapping material is charged with light, which raises electrons in the material from a ground level to a higher trapping energy level. The material is then introduced into a patient's body, where it delivers light to and activates an antibody which has been retained in cancerous tissue. The electron trapping material can be either a deep trap or shallow trap phosphor. In the former case, stimulation of the charged material with infrared energy releases electrons from their traps, resulting in the emission of light within the patient's body. In the latter case, the material emits light immediately after charging with an intensity that decreases in inverse porportion to time.

Abstract: An article, having particular use as an optical memory medium, includes a thin electron trapping photoluminescent film upon a substrate. In one preferred embodiment, a selected material is prepared in bulk, then applied in a relatively thin film to a substrate, and then heated to a sufficient temperature for a sufficient period of time such that the selected material acquires electron trapping characteristics and becomes photoluminescent. Some preferred methods of depositing the material are electron-beam deposition and sputtering. Some preferred methods of heating the material include photo crystallization and laser crystallization.

Abstract: An efficient energy upconversion unit is optically coupled to a photocathode. The upconversion unit receives incident infrared electromagnetic energy of longer wavelengths and emits, in response, electromagnetic energy within a band of shorter wavelengths to which the photocathode is more responsive. Through such energy upconversion, the photoresponse of the cathode is extended to much longer infrared wavelengths.