摘要:
An optical device for coupling the luminous output of a light-emitting diode (LED) to a predominantly spherical pattern comprises a transfer section that receives the LED's light within it and an ejector positioned adjacent the transfer section to receive light from the transfer section and spread the light generally spherically. A base of the transfer section is optically aligned and/or coupled to the LED so that the LED's light enters the transfer section. The transfer section can comprises a compound elliptic concentrator operating via total internal reflection. The ejector section can have a variety of shapes, and can have diffusive features on its surface as well. The transfer section can in some implementations be polygonal, V-grooved, faceted and other configurations.
摘要:
A cylindrical light source comprises multiple LEDs mounted on either the exterior or interior surface of the cylinder, with heat-sink fins respectively on its interior or exterior. The LEDs emit radially, but their emission is redirected along the cylinder axis by individual ellipsoidal reflectors.
摘要:
Some photovoltaic cells have a front face accepting incoming incident light and opaque gridlines overlying part of the front face, electrically bonded to the face, with upper reflective facets oblique to the plane of the front face and producing outgoing reflected light. An optical interface parallel to and in front of the front face transmits incoming light to the front face and to the gridlines and reflects back towards the front face by total internal reflection at least some of the outgoing reflected light. Some photovoltaic devices have a triple junction photovoltaic cell, a single junction photovoltaic cell, and a reflective surface arranged to distribute incoming light between the cells. The surface may be a frequency-selective mirror that apportions light so when the cells are in series the power produced, and preferably the photocurrent, is greater than if all the light fell on the triple junction cell alone.
摘要:
Some embodiments provide luminance-preserving non-imaging backlights that comprise a luminous source emitting light, an input port that receives the light, an injector and a beam-expanding ejector. The injector includes the input port and a larger output port with a profile that expands away from the input port acting via total internal reflection to keep x-y angular width of the source image inversely proportional to its luminance. The injector is defined by a surface of revolution with an axis on the source and a swept profile that is a first portion of an upper half of a CPC tilted by its acceptance angle. The beam-expanding ejector comprising a planar waveguide optically coupled to the output port of the injector. The ejector includes a smooth upper surface, and a reflective lower surface comprising microstructured facets that refract upwardly reflected light into a collimated direction common to the facets.
摘要:
An optical device for coupling the luminous output of a light-emitting diode (LED) to a predominantly spherical pattern comprises a transfer section that receives the LED's light within it and an ejector positioned adjacent the transfer section to receive light from the transfer section and spread the light generally spherically. A base of the transfer section is optically aligned and/or coupled to the LED so that the LED's light enters the transfer section. The transfer section can comprises a compound elliptic concentrator operating via total internal reflection. The ejector section can have a variety of shapes, and can have diffusive features on its surface as well. The transfer section can in some implementations be polygonal, V-grooved, faceted and other configurations.
摘要:
A passive electro-optical tracker uses a two-band IR intensity ratio to discriminate high-speed projectiles and obtain a speed estimate from their temperature, as well as determining the trajectory back to the source of fire. In an omnidirectional system a hemispheric imager with an MWIR spectrum splitter forms two CCD images of the environment. Three methods are given to determine the azimuth and range of a projectile, one for clear atmospheric conditions and two for nonhomogeneous atmospheric conditions. The first approach uses the relative intensity of the image of the projectile on the pixels of a CCD camera to determine the azimuthal angle of trajectory with respect to the ground, and its range. The second calculates this angle using a different algorithm. The third uses a least squares optimization over multiple frames based on a triangle representation of the smeared image to yield a real-time trajectory estimate.
摘要:
A passive electro-optical tracker uses a two-band IR intensity ratio to discriminate high-speed projectiles and obtain a speed estimate from their temperature, as well as determining the trajectory back to the source of fire. In an omnidirectional system a hemispheric imager with an MWIR spectrum splitter forms two CCD images of the environment. Three methods are given to determine the azimuth and range of a projectile, one for clear atmospheric conditions and two for nonhomogeneous atmospheric conditions. The first approach uses the relative intensity of the image of the projectile on the pixels of a CCD camera to determine the azimuthal angle of trajectory with respect to the ground, and its range. The second calculates this angle using a different algorithm. The third uses a least squares optimization over multiple frames based on a triangle representation of the smeared image to yield a real-time trajectory estimate.
摘要:
Optical transformer devices described herein provide a variety of area output patterns from a small light source (21). A light ejector (24) is described for transversely ejecting light injected by a light source, including a plurality of partially reflective interfaces (41) arranged along a central axis (28), the interfaces arranged so that light injected by the light source travels through each of the interfaces, the reflected light providing an area light output of the light reflected. The interfaces may utilize Fresnel reflectance or may comprise metallic or dielectric coatings. A variety of embodiments are described, such as a cylindrical configuration, a rectangular block configuration, or an N-sided polygonal configuration. In some embodiments a turning reflector (132) and polarization retarder (131) are provided to reverse the direction of light and rotate polarization on the side opposite the light source. In one embodiment, a stripe ejector (470) can be used to illuminate an LCD display.
摘要:
A light engine has a pillar with first and second ends; a circuit board on the first end of the pillar, a light source mounted on the circuit board encircling the pillar and facing towards the second end of the pillar, and a surface extending from the second end of the pillar, that surface and the exterior of the pillar between that surface and the circuit board being coated with a reflective remote phosphor that is excited by light from the light source. The light engine may be used in a light bulb, with a frosted globe enclosing the circuit board and mounted round the outer edge of the phosphor-coated surface, and an Edison screw or other standard base connected to the second end of the pillar.
摘要:
A general method is disclosed of designing two-component dichroic short-pass filters operable for incidence angle distributions over the 0-30° range, and specific preferred embodiments are listed. The method is based on computer optimization algorithms for an N-layer design, specifically the N-dimensional conjugate-gradient minimization of a merit function based on difference from a target transmission spectrum, as well as subsequent cycles of needle synthesis for increasing N. A key feature of the method is the initial filter design, upon which the algorithm proceeds to iterate successive design candidates with smaller merit functions. This initial design, with high-index material H and low-index L, is (0.75 H, 0.5 L, 0.75 H)̂m, denoting m (20-30) repetitions of a three-layer motif, giving rise to a filter with N=2m+1.