Abstract: In one embodiment, each of the output/input ports of each one of a plurality of optical splitters is connected to one of a plurality of optical switches by means of optical fibers without any fusion splicing in a majority of the optical fibers, and each of the input/output ports of each one of the switches is connected to one of the optical splitters by means of the optical fibers without any fusion splicing in a majority of the optical fibers. Each of the output/input ports of each one of the optical splitters may be directly connected to the ferrule and one of the input/output ports of one of the switches by the optical fibers. The optical splitters may be implemented in at least one planar lightwave circuit (PLC) chip. Optionally, at least one fiber holder defining a plurality of channels therein may be used to hold the optical fibers each of which is aligned with a corresponding output/input port of one of the optical splitters.

Abstract: A solid-state optical amplifier is described, having an active core and doped cladding in a single chip. An active optical core runs through a doped cladding in a structure formed on a substrate. A light emitting structure, such as an LED, is formed within and/or adjacent to the optical core. The cladding is doped, for example, with erbium or other rare-earth elements or metals. Several exemplary devices and methods of their formation are given.

Abstract: A tunable optical device uses a diffraction grating to angularly disperse a collimated beam carrying multiple wavelengths into multiple individually collimated wavelength beams, and then refocuses each of the individual collimated beams to its own focusing point on a moving plate that is located in the region of the focus plane. One or more reflective dots on the moving plate then selectively reflect particular wavelength(s) back to a first output port. The unselected wavelengths are transmitted through the moving plate, where they are then recombined and sent to a second output port. In a typical optical network architecture, the selected wavelength(s) could be viewed as the dropped traffic at a node of the optical network, while the unselected wavelengths could be viewed as the express traffic that is being passed to another node of the network. The device can also be used as a wavelength or beam combiner as well as a splitter.

Abstract: An LED array includes three or more strings of bare LEDs mounted in close proximity to each other on a substrate. The strings of LEDs emit light of one or more wavelengths of blue, indigo and/or violet light, with peak wavelengths that are less than 490 nm. Luminescent materials deposited on each of the LED chips in the array emit light of different wavelength ranges that are of longer wavelengths than and in response to light emissions from the LED chips. A control circuit applies currents to the strings of LEDs, causing the LEDs in the strings to emit light, which causes the luminescent materials to emit light. A user interface enables users to control the currents applied by the control circuit to the strings of LEDs to achieve a Correlated Color Temperature (CCT) value and hue that are desired by users, with CIE chromaticity coordinates that lie on, or near to the black body radiation curve.

Abstract: A light source for providing light comprises a light emitting layer and a lens comprising a periodic structure therein that is periodic along at least one direction in a plane. The structure includes or is formed from at least two optically transparent materials of different optical indices. The lens is separated from the light emitting layer, and the radiation propagating from the light emitting layer within an angle to a line normal to the plane will be transmitted by the lens to a far field in an index-guided mode. The separation between the light emitting layer and the lens is such that near field radiation propagating from the light emitting layer towards the lens not within said angle to the line will be scattered and redirected by the first lens to the far field to thereby collimate the radiation propagating from the light emitting layer to the far field.

Abstract: A tunable optical filter is described, utilizing a diffraction grating and a rotating mirror. By incorporating a phase screen, or the combination of a phase screen and a transmission amplitude-modulated mask, located in front of the rotating mirror, or possibly at other locations in the optical path, the selected wavelength's passband spectrum can be shaped in a variety of ways. In particular, the output spectrum of the tunable optical filter can be made flatter within the passband, while maintaining good isolation of adjacent channels or wavelengths.

Abstract: A solid-state optical amplifier is described, having an active core and doped cladding in a single chip. An active optical core runs through a doped cladding in a structure formed on a substrate. A light emitting structure, such as an LED, is formed within and/or adjacent to the optical core. The cladding is doped, for example, with erbium or other rare-earth elements or metals. Several exemplary devices and methods of their formation are given.

Abstract: A tunable optical filter integrates the functions of wavelength tuning and power isolation of back reflection. The optical signal enters a Faraday rotator twice, and isolation is provided by two birefringent crystals, having their optical axes oriented at 45 degrees with respect to each other. The two birefringent crystals are on the same side of the Faraday rotator. The integration of an optical tunable filter and an isolator function into a single packaged component helps to reduce the size and complexity of optical amplifier systems, such as EDFAs and PDFAs, operating in the 1550 nm and 1310 nm transmission bands, respectively.

Abstract: Light of at least two wavelengths is collimated in a forward path towards a reflector and light of at least one of the wavelengths is focused and detected in a return path, using in both paths a lens unit including a first convex surface and a second surface. A diffraction element diffracts the collimated light of the at least two wavelengths into different wavelength components. The reflector is moved so that one or more of the different wavelength components will be focused by the lens unit in the return path and detected. The second surface reflects the light of the at least two wavelengths from an input port towards the first convex surface and the first convex surface collimates the reflected light of the at least two wavelengths in the forward path, or the first convex surface focuses the one or more wavelength components towards the second surface that reflects the one or more wavelength components to an output port in the return path.

Abstract: The color uniformity of a light spot is measured by providing an image of the light spot by means of a camera or camera sensor with sensor elements, each of the sensor elements capturing a set of three or more color component values that together define a set of pixel values at such sensor element, wherein the image includes a plurality of sets of pixel values. The method also derives for each of the plurality of sets of pixel values at a corresponding sensor element a first ratio between a first pair of the pixel values or of values obtained therefrom in such set. Preferably a second ratio is also derived between a second pair of the pixel values or of values obtained therefrom in such set, where the second pair is different from the first pair.

Abstract: An array structure for light emitting diodes (LEDs) uses a patterned metal layer buried beneath LED chips to electrically interconnect non-adjacent chips in series, such that each chip in the LED array can be adjacently surrounded by LED chips of different colors. Thus, when the emission from the LED array is projected to a spot in the far field, its color uniformity over the spot is enhanced. Methods are also described for fabricating the multi-layer circuit board for such an array. Top and bottom patterned metal layers are formed, separated by a patterned insulating layer, so that electrical connections may be made between the metal layers. This provides “vias” between the metal layers for creating “cross-under” electrical connections under the second insulation layer, such that spatially-separated LED chips can be interconnected into strings, while maintaining electrical isolation between LED chips of different colors.

Abstract: A broad-spectrum, multiple wavelength illuminator comprises a luminescent body, and a plurality of semiconductor chips spaced apart from the luminescent body emitting light within one or more wavelength ranges towards the luminescent body, causing the luminescent body to emit light of one or more wavelength ranges. An optical element adjacent to the luminescent body collects light emitted by the luminescent body. An optical device collects light collected by the optical element. An aperture located between the optical element and the optical device passes the light emitted by the luminescent body along an optical axis, wherein light collected by the optical element and the optical device and passed by the aperture forms a beam of light illuminating a target. Alternatively, instead of being spaced apart from the chips, the luminescent body may be a layer adjacent to the chips.

Abstract: An LED array includes three or more strings of bare LEDs mounted in close proximity to each other on a substrate. The strings of LEDs emit light of one or more wavelengths of blue, indigo and/or violet light, with peak wavelengths that are less than 490 nm. Luminescent materials deposited on each of the LED chips in the array emit light of different wavelength ranges that are of longer wavelengths than and in response to light emissions from the LED chips. A control circuit applies currents to the strings of LEDs, causing the LEDs in the strings to emit light, which causes the luminescent materials to emit light. A user interface enables users to control the currents applied by the control circuit to the strings of LEDs to achieve a Correlated Color Temperature (CCT) value and hue that are desired by users, with CIE chromaticity coordinates that lie on, or near to the black body radiation curve.

Abstract: By diverting a small amount of current from a string of LED(s) powered by a LED driver at low current levels in a process of dimming the LED string, performance of the LED string light emission is improved.

Abstract: One embodiment of the invention is directed to a light mixing illuminator for illuminating an object, comprising an array of light emitting elements wherein at least some of the elements emit light of different wavelengths. An optical device is employed that focuses the light from the elements to a Fourier plane of the device, wherein the light emitting elements are arranged so that at least the zero spatial frequency components of light of the different wavelengths from the elements substantially overlap in a region at the Fourier plane. An objective is used to project the region onto the object. A mask is used that selectively blocks some of spatial frequency components of light from the elements without blocking the zero spatial frequency components of light from reaching the object.