Abstract: A method includes positioning a substrate at an initial position. The method also includes placing a filter onto the substrate. The filter is configured with a first set of layers with a maximized index and a second set of layers with a maximized index. The index for the first set of layers is greater than the index for the second set of layers. The filter has a reduced/minimal dependence on an angle of incidence (AOI) and reduced/minimal thermal dependence. The filter transmits signal photons onto a photon detector, rejects ambient photons, and increases signal-to-noise ratio of the photon detector.

Abstract: A system can comprise a first window pane configured at a first position in a semitransparent and uniform structure. The system can also include a first substrate configured with a first transparent conductive oxide (TCO) contact layer, a hole transport (HTL) layer and a first perovskite layer, wherein the first TCO contact layer, the HTL layer, and first perovskite layer are positioned at a set distance away from the first window pane in the semitransparent and uniform structure. The HTL layer includes oxides, or iodides, or organic materials. Further, the system can include a second substrate directly opposite to the first substrate, and configured with a second TCO contact layer, an electron transport (ETL) layer, and a second perovskite layer, wherein the first perovskite layer and the second perovskite layer are fused together in the semitransparent and uniform structure. The ETL layer includes oxides or organic materials.

Abstract: A system can comprise a first window pane configured at a first position in a semitransparent and uniform structure. The system can also include a first substrate configured with a first transparent conductive oxide (TCO) contact layer, a hole transport (HTL) layer and a first perovskite layer, wherein the first TCO contact layer, the HTL layer, and first perovskite layer are positioned at a set distance away from the first window pane in the semitransparent and uniform structure. The HTL layer includes oxides, or iodides, or organic materials. Further, the system can include a second substrate directly opposite to the first substrate, and configured with a second TCO contact layer, an electron transport (ETL) layer, and a second perovskite layer, wherein the first perovskite layer and the second perovskite layer are fused together in the semitransparent and uniform structure. The ETL layer includes oxides or organic materials.

Abstract: A confocal scanning system for the multispectral imaging of fluorescence from a tissue sample based on time domain mapping of spectral components of the fluorescence using coated fiber tips disposed on multimode optical fibers. A fiber grating spectrometer based on two serial arrays of coated fiber tips disposed on multi-mode fiber, and delay lines between them provide spectral slices of the florescence. The coated fiber tips are arranged such that the shortest wavelength spectral components are reflected first and the longest wavelength components last. Fiber-based delay lines delay the reflections from each successive fiber tip such that they are uniformly separated in time, and in the order of its spectral wavelength number. The spectral bins are used to colorize the images to show the presence of abnormal tissue at cellular spatial resolution. A second scan with increased laser flux can destroy the diseased tissue revealed by the first scan.

Abstract: The present invention is a confocal scanning system for the multispectral imaging of fluorescence from a tissue sample based on the mapping of the spectral components of the fluorescence into the time domain using coated fiber tips disposed on multimode optical fibers. A fiber grating spectrometer based on two serial arrays of coated fiber tips disposed on multi-mode fiber, and delay lines between them provide spectral slices of the florescence. The coated fiber tips are arranged such that the shortest wavelength spectral components are reflected first and the longest wavelength components last. Fiber-based delay lines delay the reflections from each successive fiber tip such that they are uniformly separated in time, and in the order of its spectral wavelength number. The spectral bins are used to colorize the images to show the presence of abnormal tissue at cellular spatial resolution. A second scan with increased laser flux can destroy the diseased tissue revealed by the first scan.

Abstract: Embodiments of the present invention are directed methods, apparatuses and system for establishing a linear radiant electromagnet energy field. In one embodiment of the invention, a system for providing a linear field of electromagnetic energy includes a laser, at least one length of single mode or multimode optical fiber including a core having a stitched diffraction grating of predetermined pitch for diffracting electromagnetic energy in a predetermined direction, a longitudinal optical element having a convex surface and a length corresponding to the length of optical fiber, wherein the optical element is sized such that the convex surface is positioned at a predetermined distance from the optical fiber and in a direction to receive electromagnetic energy diffracted by the grating of the optical fiber thereby establishing a linear lighting field and a lenticular array.

Abstract: A unique reflective surface is employed to compensate polarization dependence of optical taps. Specifically, the reflective surface compensates optical tap induced polarization by employing the intrinsic properties of metals rather than complex thin film stacks. To this end, a reflective thin metal film or a polished reflective metal surface may be employed. In a particular embodiment of the invention, a reflective surface that is coated with a single dielectric thin film can also be employed. In one example, the metal is preferably tungsten because it exhibits a large difference in the spread of reflectance between the s and p polarization states.

Abstract: A unique reflective surface is employed to compensate polarization dependence of optical taps. Specifically, the reflective surface compensates optical tap induced polarization by employing the intrinsic properties of metals rather than complex thin film stacks. To this end, a reflective thin metal film or a polished reflective metal surface may be employed. In a particular embodiment of the invention, a reflective surface that is coated with a single dielectric thin film can also be employed. In one example, the metal is preferably tungsten because it exhibits a large difference in the spread of reflectance between the s and p polarization states.

Abstract: The present invention is an optical spectrum analyzer (OSA) comprising a tree-structure of N-stage wavelength filters or “wavelength slicer” which “slice” the incident optical signal into desired groupings of individual sliced spectral components, each along a different output optical fiber. Cascaded fiber Bragg gratings and delay lines coupled to each output optical fiber then uniquely map the “sliced” spectral components into the time domain such that each spectral component is allocated a unique time slot.

Abstract: In accordance with the teachings of the present invention, it has been discovered that an optical analysis that is uniquely based on geometrical rather than diffraction considerations, for the purposes of controlling the size of the region from which the photoluminescence is collected, provides an optical system capable of performing photoluminescence microscopy and/or spectroscopy without the disadvantages of the prior art. It is based, in part, on the use of an optical fiber(s) as a field stop within the detection arm(s) of the optical system for coupling the photoluminescence into an optical spectrum analyzer (OSA) and/or photodetector, wherein the diameter and the numerical aperture of the optical fiber are judiciously chosen to limit the field of view, or the region from which the photoluminescence is collected.

Abstract: The purpose of the invention is to detect impurities in a semiconductor wafer (20). A laser (21) forms a light beam having a high proportion of its power at an optical frequency capable of being absorbed by the impurity to be measured. The beam is split into first (25) and second (26) light components, one of which is directed at the surface of the semiconductor wafer (20) to be tested and the other at a reference semiconductor wafer (27) containing a known quantity of the impurity to be measured. The light intensities reflected from the two wafers is detected by photodetectors (29, 30) and their difference is taken as a factor in measuring the impurity density in the wafer under test. A polarizer (33) polarizes the beam such as to maximize p-type component and minimize s-type components. Reflection from each of the two wafers (20, 27) is at the principal angle.

Abstract: Individual defects in or near the surface of a silicon wafer (16) are detected by directing a time-modulated laser beam (44), having an energy level above the bandgap energy of the silicon material, towards the wafer. The beam (44) is focused to a one to two micron spot (48) on the wafer surface to photoexcite (i.e., pump) a high density of electrons and holes which changes the infrared reflectance in the area of the pumped spot. A probe beam (34) of infrared radiation is directed at the surface (0.126 square mm in area) of the substrate (16) and at a small angle thereto and the reflection thereof monitored by a detector (54). The pumped spot (48) is raster scanned within the area of the probe beam spot (38). The detector (54) detects only that portion of the intensity of reflected probe beam (34) that is modulated by the pump beam frequency to create a video display having a high spatial resolution showing individual defects.

Abstract: Molybdenum thin films deposited by pyrolytic decomposition of Mo(CO).sub.6 attain, after anneal in a reducing atmosphere at temperatures greater than 700.degree. C., infrared reflectance values greater than reflectance of supersmooth bulk molybdenum. Black molybdenum films deposited under oxidizing conditions and annealed, when covered with an anti-reflecting coating, approach the ideal solar collector characteristic of visible light absorber and infrared energy reflector.