Abstract: Various embodiments may provide a method of fabricating a meta-lens structure. The method may include forming a first dielectric layer in contact with a silicon wafer. The method may also include forming a second dielectric layer in contact with the first dielectric layer. A refractive index of the second dielectric layer may be different from a refractive index of the first dielectric layer. The method may further include, in patterning the second dielectric layer. The method may additionally include removing at least a portion of the silicon wafer to expose the first dielectric layer.

Abstract: An optical transmitter module includes: a low-speed light emitting device that emits an optical signal at a first given wavelength; a high-speed light emitting device that emits an optical signal at a second given wavelength; and a first filter that transmits one and reflect the other of the first- and second-given-wavelength optical signals to send the optical signal to an optical receiver module. The optical receiver module includes: a low-speed light receiving device that receives the optical signal at the first given wavelength; a high-speed light receiving device that receives the optical signal at the second given wavelength; and a second filter that transmits one and reflects the other of the first- and second-given-wavelength optical signals to send the first-given-wavelength optical signal to the low-speed light receiving device, and the second-given-wavelength optical signal to the high-speed light receiving device.

Abstract: A scatterometer performs diffraction based measurements of one or more parameters of a target structure. To make two-color measurements in parallel, the structure is illuminated simultaneously with first radiation (302) having a first wavelength and a first angular distribution and with second radiation (304) having a second wavelength and a second angular distribution. The collection path (CP) includes a segmented wavelength-selective filter (21, 310) arranged to transmit wanted higher order portions of the diffracted first radiation (302X, 302Y) and of the diffracted second radiation (304X, 304Y), while simultaneously blocking zero order portions (302?, 304?) of both the first radiation and second radiation.

Abstract: An optical multiplexer/demultiplexer may include some beam splitters on the first surface, a first reflector on the first surface and between the beam splitters, and a second reflector on the second surface. Light propagates between the first surface and the second surface. The light transmission body has some first input/output sections on the first surface for inputting or outputting the respective signal beams. The light transmission body has a second input/output section on the second surface for inputting or outputting the multiplexed signal beam. Each of the beam splitters is placed at a corresponding one of the first input/output sections to pass a corresponding one of the signal beams. The first reflector stays away from any one of the first input/output sections.

Abstract: A light guide system for a physiological sensor includes a light channel in optical communication with an emitter and a light channel in optical communication with a detector. The light channels are formed of a bio-compatible resilient plastic, such as a silicone, that is blended with a colorant. Each light channel has an optical transmission spectrum that passes the emitter spectral band and rejects most or all ambient light. The colorant can be a pigment provided as a suspension in a liquid or a dye provided in liquid form. The optical transmission spectrum defines a longpass optical filter where the shortest wavelength of the optical spectrum of the emitter is greater than the transition wavelength of the longpass optical filter. Each of the light channels is configured to be in contact with the skin, thereby reducing or eliminating optical loss due to transmission through an air gap.

Abstract: Devices and methods are disclosed for characterizing point flaws (including pinholes and point defects) of an optical filter. A passband test is performed, including: illuminating the optical filter with passband illumination whose spectral range at least overlaps a passband of the optical filter; acquiring a passband map of the optical filter using a two-dimensional array of photodetectors while illuminating the optical filter with the passband illumination; and identifying point defects of the optical filter as low intensity locations of the passband map. A stopband test is performed, including: illuminating the optical filter with stopband illumination whose spectral range lies entirely outside of the passband of the optical filter; acquiring a stopband map of the optical filter using the two-dimensional array of photodetectors while illuminating the optical filter with the stopband illumination; and identifying pinholes of the optical filter as high intensity locations of the stopband map.

Abstract: Optical filter assemblies based on either a parallel plate optical assembly or a polarization separation optical assembly are described. The optical assemblies usefully separate randomly polarized light with at least two transmission wavelengths from an optical communication signal.

Abstract: The present disclosure relates to thin film optical interference filters. The filters include a substrate and a plurality of alternating material layers deposited on the substrate. When operated at about 45° angle of incidence, the filters exhibit at least one of improved polarization splitting, edge steepness, bandpass bandwidth, and blocking, relative to conventional thin film interference filters.

Abstract: A method is provided that includes providing a light source having a light emitting diode (LED) that emits a light. A polarization conversion system (PCS) is located adjacent the LED and has both a linear polarizer and a wave plate. A polarizing beam splitter (PBS) is adjacent the light source and an imaging device is adjacent the PBS. The wave plate of the PCS is rotated to a first position, and a first light is emitted by the LED in the first light source. This first light is converted to circular polarization. This first light travels to the PBS where it is reflected onto the imaging device. The wave plate is then rotated to a second position, and a second light is emitted by the light source. This second light is converted to circular polarization and reflects from the PBS onto the imaging device.

Abstract: An image sensor including a pixel unit, the pixel unit including a photodiode, a first color filter and a second color filter each disposed in a different position on a plane above the photodiode, and a first on-chip lens disposed over the first color filter and a second on-chip lens disposed over the second color filter.

Abstract: A micro projection system includes a primary prism as a light guide device. The primary prism has a bottom face and two slope faces. A light source module and a collimation lens are arranged at the bottom face of the primary prism to project red, green, and blue lights onto one of the slope faces of the primary prism to be consolidated by a wedge prism group and reflected toward a polarization beam splitting wedge prism arranged at another slope face, where the light is split into two polarized lights that are then emitted out of the primary prism to be processed and combined as light of consistent polarization by a lens array and a polarization conversion film so as to facilitate condensation and projection of the light by a polarization beam splitter and a projection lens.

Abstract: Coatings for optical devices, such as beamsplitters, are provided. The coatings include at least one bilayer of a layer of a material having an index of refraction n1 in contact with a layer of a material having an index of refraction n2 and an uppermost layer of a material having an index of refraction n3 over the bilayer, wherein n3>n2>n1. The bilayer(s) can be composed of BaF2 and KRS5. The uppermost layer can be composed of Ge. Certain coatings provide beamsplitters which exhibit highly efficient emission over broad spectral ranges.

Abstract: A color filter, comprising: a substrate; a plurality of first pixel regions, a plurality of second pixel regions and a plurality of third pixel regions defined on a first side of the substrate; and a band pass filter layer comprising a first medium sub layer, a second medium sub layer and a third medium sub layer successively formed on a second side of the substrate or on the plurality of first pixel regions, the plurality of second pixel regions and the plurality of third pixel regions, wherein the second medium sub layer has a first thickness in a first medium area corresponding to the first pixel region, a second thickness in a second medium area corresponding to the second pixel region and a third thickness in a third medium area corresponding to the third pixel region. The present invention also relates to a method for manufacturing the color filter.

Abstract: A projection apparatus is disclosed. The projection apparatus includes a light source module, a first light splitting element, a first light valve unit, a first light modulator, a second light modulator and a light consolidating element. A light beam is provided by the light source module, and is split into a first and a second polarized light beam by the first light splitting element. In different time sequences, the first and the second polarized light beams are formed into a first, a second, a third and a fourth image light by the first light valve unit. Then, these image lights are transformed into viewing angle images by the first and the second light modulators. Then, via the light consolidating element, the first, the second, the third and the fourth view angle images are projected to a viewer and a stereoscopic image is formed.

Abstract: A polarizing beam splitter has a pair of opposed transparent prism substrates with a refractive index n0, and providing at least one input port and at least one output port. The input port accepts light incident over a range of operational angles including a central operational angle. A multilayer thin film structure is sandwiched between the pair of opposed transparent substrates and consists essentially of a plurality of layers l1 . . . lm having respective refractive indices n1 . . . nm, wherein at least three of said refractive indices n1 . . . nm are different, and wherein the refractive index of the substrates n0 lies between the highest refractive index nH and lowest refractive index nL, and wherein nH, nL and n0 define a Brewster angle ?0B: ? 0 ? B = arcsin ( n L ? n H n 0 ? n L 2 + n H 2 ) , and a critical angle ?c: ? C = arcsin ? ( n L n 0 ) . The refractive indices n0 and n1 . . .

Abstract: In one embodiment, an apparatus comprises an optical system with multiple detectors and a processor. The optical system is configured to produce images of an optical source in a first dimension and a second dimension substantially orthogonal to the first dimension at each detector at a given time. Each image from the images is based on an interference of an emission from the optical source in a first direction and an emission from the optical source in a second direction different from the first direction. The processor is configured to calculate a position in a third dimension based on the images. The third dimension is substantially orthogonal to the first dimension and the second dimension.

Abstract: A method of forming a non-polarizing pellicle beamsplitter having a desired power-tap ratio. The method includes the operation of forming a base layer having a base refractive index on a substrate and arranging a plurality of alternating layers having relatively high and low indexes of refraction respectively over the base layer. The thickness of each of the high index and low index layers is selected to substantially eliminate polarization of the optical beam. The method further includes the operation of removing a selected area of the substrate to create an optical pathway comprised of both the base layer and the plurality of alternating layers, and where the optical pathway is configured to transmit and reflect a selected amount of light in the optical beam.

Abstract: High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.

Abstract: An optical scanning unit includes a light source including a plurality of light-emitting elements; a light detector to detect a light beam emitted from the light source; a light-flux splitter, angled to the optical axis of the light beam emitted from the light source, having an aperture, a portion of reduced thickness susceptible to warping, a concave face of the warped light-flux splitter as a reflecting face, and a convex face of the warped light-flux splitter opposite the concave face as a non-reflecting face; and a light-flux splitter pressing unit to press the light-flux splitter onto a light-flux splitter holding member without blocking the aperture. Light beam passed the aperture is used as a write-use light flux. The reflecting face reflects a light flux other than the write-use light flux as a monitor-use light flux. The light-flux splitter pressing unit presses a portion of maximum convexity of the non-reflecting face.

Abstract: An optical image splitter disposed in the path of image-bearing light along an optical axis has a coated dichroic surface disposed at an angle of 15 degrees or less relative to incident light along the optical axis. The coated dichroic surface has a number of layers of material, the of layers including layers having a first refractive index, nL, and layers having a second refractive index, nH, greater than the first refractive index. The coated surface transmits light of at least a first wavelength range to form a first image at an image plane and reflects light of a second wavelength range to form a second image at the image plane.

Abstract: An optical touch control system. A monitor includes a first side, a second side, a third side, and a fourth side sequentially connected to each other. A first light guide, a second light guide, and a third light guide are respectively disposed on the first, second, and third sides of the monitor. A first beam splitter is adjacent to the first and second light guides. A second beam splitter is adjacent to the second and third light guides. A first light source and a second light source are respectively adjacent to the first and second beam splitters. A first image sensor is disposed between the first and fourth sides of the monitor. A second image sensor is disposed between the third and fourth sides. The first and second image sensors receive light transmitted onto the monitor via the first, second, and third light guides, identifying touch control operations.

Abstract: A projection image display apparatus includes: a light source; an illumination optical system that uniformly irradiates a surface of an image modulation element serving as a primary image surface with a light beam emitted from the light source; and a projection optical system that enlarges and projects image information on the primary image surface modulated by the image modulation element onto a screen serving as a secondary image surface, and that includes a first optical system that forms an intermediate image from the image information, a single-image second optical system that enlarges and projects the intermediate image to display a single image on the screen, a plural-image second optical system that enlarges and projects the intermediate image to display plural images on the screen, and an optical path switching mechanism that selectively guides a light beam from the first optical system to the single-image or plural-image second optical system.

Abstract: It is an object of the present invention to provide an optical waveform shaping device of high resolution. The above-mentioned problem is solved by an optical waveform shaping device (10) comprising a branching filter (11) for dividing the light beam from a light source into light beams of each frequency, a condensing part (12) for condensing a plurality of light beams divided by the branching filter (11), a polarization separation means (13) for adjusting the polarizing planes of the light beams having passed through the condensing part (12), and a spatial light modulator (14) having a phase modulation part and an intensity modulation part where the light beams having passed through the polarizing plate (13) are incident.

Abstract: An optical touch control system. A monitor includes a first side, a second side, a third side, and a fourth side sequentially connected to each other. A first light guide, a second light guide, and a third light guide are respectively disposed on the first, second, and third sides of the monitor. A first beam splitter is adjacent to the first and second light guides. A second beam splitter is adjacent to the second and third light guides. A first light source and a second light source are respectively adjacent to the first and second beam splitters. A first image sensor is disposed between the first and fourth sides of the monitor. A second image sensor is disposed between the third and fourth sides. The first and second image sensors receive light transmitted onto the monitor via the first, second, and third light guides, identifying touch control operations.

Abstract: A two-photon absorption (TPA) switch is provided for minimizing which-path information in quantum optic interference. The TPA switch includes a pulse laser, first and second dichroic mirrors, a down-conversion crystal, a reflector, and a beam-splitter. The pulse laser emits a pump photon traveling along a photon-incident direction. The dichroic mirrors are disposed along the incident direction and oriented to enable photons to either pass there-through or perpendicularly reflect perpendicular to the incident direction. The down-conversion crystal is disposed between the dichroic mirrors along the incident direction and is non-critically phase-matched with signal and idler photons controlled by temperance of the crystal. The beam-splitter is disposed along one of the reflection directions to probabilistically reflect one of the signal and idler photons to pass through the crystal.

Abstract: In one embodiment, the modular display includes aggregates of individual panel tiles arranged between two large plastic sheets. The footprint of the large plastic sheet sandwich becomes the dimension of the display screen. The tilettes are phosphor emission panels with a full complement of emittable pixels. By separating the tilettes from the final full dimension sheet, the tilettes can be manufactured in transportable sizes and the outer full dimension sheets can be rolled for easy transport to the final install location.

Abstract: The present invention relates to a projection device for holographic reconstruction of scenes, said device comprising at least one light modulator device and at least one light source which emits sufficiently coherent light for the generation of a wave front of a scene, which is encoded in the light modulator device. A Fourier transform (FT) of the light which is emitted by the light source and modulated by the light modulator device is projected by a projection means on to a screen. Further, the wave front which is encoded on the light modulator device is projected by the projection means into at least one virtual observer window in an observer plane. For tracking the observer window according to a change in an eye position of the at least one observer, the inventive device comprises at least one deflection means, which is disposed between the light modulator device and the screen.

Abstract: A multilayer optical film body includes a first and second packet of microlayers. Each packet partially transmits and partially reflects light over an extended wavelength range, such as the visible region, for normally incident light polarized along a first principal axis of the film body. In combination, the first and second packets have an intermediate reflection and transmission (e.g. 5-95% internal transmission, on average) for the normally incident light, and similar intermediate reflection/transmission (e.g. 10-90% internal transmission, on average) for oblique light. The packets are laminated or otherwise connected so that light can pass through the packets sequentially. In at least a first test area of the film body, a high frequency spectral variability of the combination of packets is less than a high frequency spectral variability of the first packet by itself, and may also be less than a high frequency spectral variability of the second packet by itself.

Abstract: An optical component emits or transmits laser light of a wavelength of 460 nm or less, and a first coating formed from a dielectric film is applied upon at least a part of the surface thereof, and a second coating B formed from a dielectric film containing a noble metal or platinum group element is applied upon the first coating.

Abstract: The present invention provides an interferometer apparatus comprising a matter-wave guide enclosing an area, wherein a flux of particles may be guided in the matter-wave guide in at least two opposite paths, the matter-wave guide is rotatable relative to an inertial frame of reference; a first beam splitter to split the first beam to at least second and third beams, each of the second and third beams is to be guided in another path of the two opposite paths; and a second beam splitter allowing particles of the second and third beams to exit the matter-wave guide in a first probability and to stay in the matter-wave guide in a second probability.

Abstract: High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.

Abstract: An image pickup apparatus includes a light-beam splitting mirror configured to transmit and reflect incident light that has entered the light-beam splitting mirror through a photographing optical system; an image sensor that receives light transmitted through the light-beam splitting mirror; an autofocus detecting unit that receives light reflected by the light-beam splitting mirror; a signal processing unit configured to process an image pickup signal of the image sensor; and a display unit configured to display an image being photographed, on the basis of an image signal obtained at the signal processing unit. In the image pickup apparatus, the light-beam splitting mirror has spectral characteristics including a reflectivity of 25% or more and 35% or less at a wavelength of 400 to 650 nm and a reflectivity of 60% or more at a wavelength of about 700 nm through optimization.

Abstract: A DPSK demodulator is implemented in Sagnac interferometer configuration with a delay line element introduced in one or both of the optical paths of the transmitted and reflected beams. Because the two reflected and transmitted beams travel on the same optical path (though in opposite directions), the Sagnac interferometer provides all the advantages of a common-path interferometer, is thermally and mechanically stable, and the phase requirements are greatly reduced. In its simplest form, the Sagnac DPSK demodulator. In the preferred embodiment, the beam-splitting surface and one of the mirrors are combined into a rhomb beam-splitter structure and the other two mirrors into a right-angle prism. In a DQPSK embodiment, the input beam is split by an upfront beam splitter into two parallel beams that are then directed toward the rhomb-beam-splitter/right-angle-prism combination of the invention.

Abstract: A projector has: light source (1R, 1G, 1B); a light modulation unit (6) that modulates a light emitted from the light source based on image signals; a display control unit (41) that outputs the image signals including main cyclic image signals to the light modulation unit, and controls the display thereof; a projection unit (7) that projects the image based on the light modulated by the light modulation unit; and an imaging unit (40) that captures an image to be displayed based on the light projected from the projection unit, and the display control unit inserts a correction image signal for projecting a correction image, which is visually recognized as a uniform white or gray screen when time integration is performed, between the cyclic main image signals.

Abstract: Rhomb beam splitters are used to implement various optical demodulators, in particular PSK and DPSK demodulators. The parallel beam-splitting and reflective surfaces of the rhomb structure produce reflection and transmission beams that exit the beam splitter parallel to one another and with a relative phase shift determined by the distance between the surfaces. These features afford the advantages of low cost, compactness, easily tunable, and temperature-insensitive optical structures for constructing a variety of optical demodulators.

Abstract: A monolithic Mach-Zehnder Interferometer (MZI) is provided for photon beam-splitting and beam-combining with accurate super-positioning of the outgoing beams, which creates the interference. The MZI includes a complimentary pair of right-isosceles triangular prisms, and several reflector units. The triangular prisms are configurable to physically join together along associated hypotenuse surfaces that form a beam-splitter interface, thereby producing a rectangular prism having a square cross-section with four outer side surfaces. Each reflector unit forms a right-isosceles mirror that rigidly faces a corresponding surface of the four outer side surfaces of the rectangular prism. The MZI further includes a spacer disposed between the corresponding surface and the each reflector unit.

Abstract: A prism monomer for use in a digital light processing projection device includes a plastic triangular prism having a hypotenuse surface and a glass sheet. The glass sheet has two opposite surfaces. One surface of the glass sheet is attached to the hypotenuse surface of the plastic triangular prism and the other surface of the glass sheet is formed with an anti-reflective coating.

Abstract: A monolithic frame for optics used in interferometers where the material of the monolithic frame may have a substantially different coefficient of thermal expansion from the beamsplitter and compensator without warping, bending or distorting the optics. This is accomplished through providing a securing apparatus holding the optics in place while isolating the expansion thereof from the expansion of the frame. Stability in optical alignment is therefore achieved without requiring a single material or materials of essentially identical coefficients of thermal expansion. The present invention provides stability in situations where it is not possible to utilize a single material for every component of the interferometer.

Abstract: Rhomb beam splitters are used to implement various optical demodulators, in particular PSK and DPSK demodulators. The parallel beam-splitting and reflective surfaces of the rhomb structure produce reflection and transmission beams that exit the beam splitter parallel to one another and with a relative phase shift determined by the distance between the surfaces. These features afford the advantages of low cost, compactness, easily tunable, and temperature-insensitive optical structures for constructing a variety of optical demodulators.

Abstract: A beam combining system suitable of pulsed fiber laser applications is able to produce non-spatial-dispersive beams using an highly efficient filter, such as a multilayer dielectric filter, in transmission and reflection configurations. The techniques therefore can overcome constraints on laser line-width and beam width and allow for more stable systems for high peak power pulsed laser energy, such as may be used in extreme ultraviolet lithography and other applications.

Abstract: An improved optic system for measuring and/or controlling displacement, force, pressure, position, or chemistry is disclosed. This apparatus allows for more accurate, robust, and economical communication between the transducer (or control input element) and the reader device (or control output), allows the use of a single optic fiber and/or or a gap for the communication link, and produces substantial insensitivity to attenuation due to mechanical, chemical, thermal, and radiation effects acting on the optic fiber or open space in which the signal propagates. It is also significantly immune to interference from electromagnetic radiation, since the link can be easily produced as a non-conductor which will not propagate unwanted electrical energy or lightning, and is intrinsically safe from igniting fires or explosions. It also facilitates use on rotating machinery and remote location of the transducer by the ability to transmit the signal across a large gap or air space.

Abstract: Wavefront control techniques are provided for the alignment and performance optimization of optical devices. A Shack-Hartmann wavefront sensor can be used to measure the wavefront distortion and a control system generates feedback error signal to optics inside the device to correct the wavefront. The system can be calibrated with a low-average-power probe laser. An optical element is provided to couple the optical device to a diagnostic/control package in a way that optimizes both the output power of the optical device and the coupling of the probe light into the diagnostics.

Abstract: A rhomb beam splitter, rather than a conventional cube, is used in combination with a mirror reflecting both the reflected and transmitted beams to obtain a delay-line interferometer demodulator with a substantially common path. This significantly reduces the sensitivity of the device to environmental changes and also greatly simplifies the manufacture process. A polarization-insensitive coating or a wave plate, a thermal phase tuner with a micro-heater, and two compensator plates are used in the paths of the beams to balance the optical path lengths and to compensate for polarization and environmental effects.

Abstract: Disclosed are a system and method for microprojection that uses multiple imagers to produce a high resolution output image. Each of a set of imagers produces a portion of the final image. Relay lenses then tile the individual image portions together into a combined image. Because the height of the individual imagers is smaller than the height of a monolithic imager, they can fit into a very thin device. The combined image has a resolution equal to the sum of the resolutions of the individual imagers. The individual images are tiled together within the microprojector itself rather than on a projection screen. This allows the tiling to be adjusted once at the factory and set forever. In some embodiments, the light created for use by the microprojector is split by a polarizing beamsplitter. Each resultant polarized beam is then sent to an imager. Another polarizing beamsplitter combines the individual images.

Abstract: A system and method for uniform light generation in projection display systems. An illumination source comprises a light source to produce colored light, and a scrolling optics unit optically coupled to the light source, the scrolling optics unit configured to create lines of colored light from the colored light, and to scroll the lines of colored light along a direction orthogonal to a light path of the illumination source. The scrolling optics unit comprises a single light shaping diffuser to transform the colored light into the lines of colored light, an optical filter positioned in the light path after the light shaping diffuser, and a scrolling optics element positioned in the light path after the optical filter. The single light shaping diffuser is capable of simultaneously transforming colored light into lines of colored light having substantially uniform intensity to provide uniform illumination.

Abstract: A projection system comprising a first imaging component, at least a second imaging component, and a color combiner. The first and second imaging components each comprise an imager and a reflective polarizer that is configured to at least partially separate a light beam from the imager into a first portion and second portion, where the first portion and the second portion have substantially orthogonal polarization states. The first portions of the light beams are directed in the same direction above or below a plane defined by the second portions of the light beams. The color combiner is configured to combine the second portions of the light beams, where the second portions of the light beams have substantially orthogonal polarization states prior to entering the color combiner.

Abstract: High-power, phased-locked, laser arrays as disclosed herein utilize a system of optical elements that may be external to the laser oscillator array. Such an external optical system may achieve mutually coherent operation of all the emitters in a laser array, and coherent combination of the output of all the lasers in the array into a single beam. Such an “external gain harness” system may include: an optical lens/mirror system that mixes the output of all the emitters in the array; a holographic optical element that combines the output of all the lasers in the array, and an output coupler that selects a single path for the combined output and also selects a common operating frequency for all the coupled gain regions.

Abstract: Polymer fibers are formed with concentric alternating layers of different polymer materials. The layers pairs have cross-sectional thicknesses selected for reflecting light at a selected visible wavelength. A cross-sectional dimension of the core is at least ten times an average of the selected thicknesses of the alternating layers. Some articles formed by the fibers are formed by attaching one fiber to another: the color of the fibers at the point of attachment is different from the colors of the fibers elsewhere. The fibers may be deformed to change its color properties by elongating the cross-section of the polymer fiber along a first cross-sectional axis. In some embodiments, the fibers are polarization sensitive.

Abstract: Various embodiments described herein comprise mixers comprising a light pipe having input and output ends and a central region therebetween. An optical path extends in a longitudinal direction from the input end through the central region to the output end. The central region of the light pipe comprises one or more rippled reflective sidewalls having a plurality of elongate ridges and valleys and sloping surfaces therebetween. Light from the input end propagating along the optical path reflects from the sloping surfaces and is redirected at a different azimuthal direction toward the output end thereby mixing the light at the output end. Illuminance and/or color mixing can therefore be provided.

Abstract: A broadband anti-reflection apparatus for use with terahertz radiation includes a layer having an outer surface comprising a plurality of pyramid structures having about a 30 ?m to about a 110 ?m period, and wherein reflectance of the terahertz radiation is reduced compared to a layer comprising a planar outer surface. Also disclosed is a method for modifying terahertz radiation which includes receiving terahertz radiation on a device having an anti-reflection layer having an outer surface comprising a plurality of pyramid structures having about a 30 ?m to a 110 ?m period, and modifying the terahertz radiation passing through the device or processing the terahertz radiation in the device.