Abstract: A head-mounted imaging apparatus includes a frame that houses a left-eye and a right-eye imaging apparatus. Each imaging apparatus forms a virtual image to an eye of an observer and includes a projector, a planar waveguide, and an optical coupler. The projector is supported by a temple member of the frame and emits a central projected light beam along a projection axis. The planar waveguide accepts the projected light beam through an input aperture and forms an expanded light beam that is output from an output aperture and directed toward the observer's eye. The optical coupler receives the central projected light beam along a first axis that is at an obtuse angle with respect to the waveguide surface, and the optical coupler redirects the central projected light beam along a second axis that is at an acute angle with respect to the waveguide surface.

Abstract: An optoelectronic circuit having a substantially planar double-sided substrate, each side of which has a respective plurality of electrically conducting tracks and a respective plurality of planar optical waveguides. The substrate also has at least one via crossing the substrate in a manner that can be used to establish an optical path across the substrate, e.g., between optical waveguides located on different sides thereof. In an example embodiment, the electrically conducting tracks and planar optical waveguides are configured to operatively connect various optoelectronic devices and auxiliary electrical circuits attached to the two sides of the substrate using hybrid-integration technologies. In some embodiments, two or more of such double-sided substrates can be stacked and optically and electrically interconnected to create an integrated three-dimensional assembly.

Abstract: An optical coupler at an edge of a photonic integrated circuit (PIC) is provided and configured to match a mode of a waveguide of the PIC to a mode of an external optical fiber. A core of the waveguide terminates prior to the edge and can include an inverted taper for mode enlargement. The waveguide cladding includes an inverted taper and is surrounded by an outer cladding material of lower refractive index, forming a second waveguide. The cladding and outer cladding cooperate to guide light between the core and the edge while the inverted taper contributes to mode enlargement. The outer cladding material is selected to have a refractive index which facilitates the mode matching to optical fiber. The coupler can be provided using lithography. Material underneath the waveguide cladding can be removed by an undercutting process and the outer cladding material deposited in place thereof.

Abstract: Energy efficient thermo-optic phase shifters have a configuration with two sections of a waveguide adjacent for heating by a common heater. A loop section can connect the two heated waveguide sections. Further improved efficiency can be achieved in which the heated sections are curved to allow closer placement of the adjacent waveguides. The heater can be curved to follow the configuration of the curved heated waveguide sections. Energy efficiency gains can be up to approximately a factor of two over corresponding traditional thermo-optical phase shifter designs.

Abstract: Embodiments disclosed herein relate generally to forming a gate layer in high aspect ratio trenches using a cyclic deposition-etch process. In an embodiment, a method for semiconductor processing is provided. The method includes performing a cyclic deposition-etch process to form a conformal film over a bottom surface and along sidewall surfaces of a feature on a substrate. The method includes reflowing the conformal film. The method includes forming a cap layer on the reflowed film. The method includes depositing a crystalline film on the cap layer. The method includes crystallizing the reflowed film and the cap layer after depositing the crystalline film.

Abstract: An example embodiment may include an interferometer. The interferometer may include a multimode waveguide with an input waveguide optically coupled to a first side of the multimode waveguide, for feeding a light signal to the multimode waveguide. The interferometer may also include a first waveguide at one end optically coupled to a second side of the multimode waveguide, and at the other end terminated by a first waveguide mirror. The interferometer may also include a second waveguide at one end optically coupled to the second side of the multimode waveguide and at the other end terminated by a second waveguide mirror. The multimode waveguide may be adapted to distribute the light signal towards the first and second waveguide mirror via the first waveguide and via the second waveguide.

Abstract: A method of forming an integrated circuit is disclosed. The method includes: (i) forming at least a pair of optoelectronic devices from at least a first wafer material arranged on a semiconductor substrate, the first wafer material different to silicon; (ii) etching the first wafer material to form a first recess to be filled with a second material; (iii) processing the second material to form a waveguide for coupling the pair of optoelectronic devices to define an optical interconnect; and (iv) bonding at least one partially processed CMOS device layer having at least one transistor to the second semiconductor substrate to form the integrated circuit, the partially processed CMOS device layer arranged adjacent to the optical interconnect. An integrated circuit is also disclosed.

Abstract: A backlight device is provided with: LEDs; a light guide plate having a light-receiving face, a light-exiting surface, and an opposite plate surface; a prism sheet that is disposed on the light-exiting side of the light guide plate and that includes a plurality of light-exiting side prisms aligned along a second direction; a light-exiting surface-side prism portion that is disposed in the light-exiting surface of the light guide plate and that includes a plurality of light-exiting surface-side prisms aligned along the second direction; a light emission reflection portion that is disposed in the opposite plate surface of the light guide plate and that includes a plurality of reflection units aligned along a first direction at an interval; and an opposite plate surface-side prism portion that is disposed in the opposite plate surface of the light guide plate and that includes a plurality of opposite plate surface-side prisms aligned along the second direction.

Abstract: A right-angle bending waveguide includes a circular-hole-type square-lattice photonic crystal (PhC) and a single compensation scattering rod having a low refractive index. The right-angle bending waveguide is a PhC formed from first dielectric rods having a low refractive index arranged in a background dielectric having a low refractive index according to a square lattice. In the PhC, one row and one column of the first dielectric rods having a high refractive index are removed to form the right-angle bending waveguide. A second dielectric rod having a high refractive index is arranged at a corner of the right-angle bending waveguide. The second dielectric rod is the compensation scattering rod or an air hole. The first dielectric rods are circular rods having the low refractive index or air holes.

Abstract: Arrays of integrated analytical devices and their methods for production are provided. The arrays are useful in the analysis of highly multiplexed optical reactions in large numbers at high densities, including biochemical reactions, such as nucleic acid sequencing reactions. The integrated devices allow the highly sensitive discrimination of optical signals using features such as spectra, amplitude, and time resolution, or combinations thereof. The arrays and methods of the invention make use of silicon chip fabrication and manufacturing techniques developed for the electronics industry and highly suited for miniaturization and high throughput.

Abstract: A semiconductor optical apparatus is disclosed, wherein the semiconductor optical apparatus comprises a first waveguide region defining a first mode size and a second active waveguide region defining a second mode size being smaller than the first mode size. The second active waveguide region is optically coupled to the first waveguide region and the second active waveguide region comprises a lower multiple quantum well layer and an upper multiple quantum well layer located above the lower multiple quantum well layer. The lower multiple quantum well layer is physically separated from the upper multiple quantum well layer by a spacer layer. The upper multiple quantum well layer comprises a mode transformation region configured to reduce the size of an optical mode from the first mode size to the second mode size.

Abstract: Methods, systems, and devices are disclosed for implementing athermal optical devices based on composite structures having different components with different thermal properties such as a composite structure having materials of positive and negative thermo-optic effects or a composite structure having materials exhibiting different thermal expansion coefficients.

Abstract: A base device has a first waveguide positioned on a first base. The waveguide is at least partially defined by a ridge extending away from the first base. An auxiliary optical device has a second waveguide positioned on a second base. The second optical device is immobilized on the base device such that the second waveguide is between the first base of the first optical device and the second base of the auxiliary device. The first waveguide is optically aligned with the second waveguide such that the first waveguide and second waveguides can exchange optical signals.

Abstract: Disclosed herein is a fiber optic-to-waveguide coupling assembly with an overlap for edge coupling. The fiber optic-to-waveguide coupling assembly includes a first coupler having a substrate and at least one data fiber, and an interposer with at least one waveguide. A first coupler overlap portion of the substrate is positionable proximate a first interposer overlap portion of the interposer to form a first overlap therebetween to align the at least one data fiber with the at least one waveguide. The substrate and the interposer may each include complementary alignment features to further align the at least one data fiber and the at least one waveguide. The fiber optic-to-waveguide coupling assembly provides simple and accurate alignment with simplified manufacture and assembly.

Abstract: Described herein are photonic systems and devices including a optical interface unit disposed on a bottom side of a photonic integrated circuit (PIC) to receive light from an emitter of the PIC. A top side of the PIC includes a flip-chip interface for electrically coupling the PIC to an organic substrate via the top side. An alignment feature corresponding to the emitter is formed with the emitter to be offset by a predetermined distance value; because the emitter and the alignment feature are formed using a shared processing operation, the offset (i.e., predetermined distance value) may be precise and consistent across similarly produced PICs. The PIC comprises a processing feature to image the alignment feature from the bottom side (e.g., a hole). A heat spreader layer surrounds the optical interface unit and is disposed on the bottom side of the PIC to spread heat from the PIC.

Abstract: A waveguide includes a first layer and a second layer. The first layer comprises a material of a first refractive index. The second layer is surrounded by the first layer and comprises a material of a second refractive index greater than the first refractive index. The second layer comprises a main body, a first fork and a second fork. The main body has a first substantially constant thickness. The first fork is extended from the main body and has a first tapering end exposed by the first layer. The first fork has the first substantially constant thickness. The second fork is extended from the main body and has a second tapering end exposed by the first layer. The second fork has the first substantially constant thickness.

Abstract: An optical device comprises a transparent plate the first surface of which is reflective; a first partially reflective and partially transmissive layer covering a second surface of the transparent plate opposite the first surface, and a second layer covering the surface of the first layer opposite the transparent plate, wherein the second layer is made of a material having an optical index which differs from the optical index of the transparent plate by less than 10% and preferably by less than 5%, and the second layer comprises, on the surface thereof opposite the first layer, structures forming a diffraction grating suitable for promoting the extraction of light towards the outside of the transparent plate.

Abstract: A light-emitting diode (LED) package includes a light-emitting structure, an optical wavelength conversion layer on the light-emitting structure, and an optical filter layer on the optical wavelength conversion layer. The light-emitting structure includes a first-conductivity-type semiconductor layer, an active layer on the first-conductivity-type semiconductor layer, and a second-conductivity-type semiconductor layer on the active layer, and emits first light having a first peak wavelength. The optical wavelength conversion layer absorbs the first light emitted from the light-emitting structure and emits second light having a second peak wavelength different from the first peak wavelength. The optical filter layer reflects the first light emitted from the light-emitting structure and transmits the second light emitted from the optical wavelength conversion layer.

Abstract: A photonic device for converting optical modes of optical beams includes a first port to receive a first beam having a first mode, a mode converter and a second port to transmit the first beam. The mode converter is configured to broaden the first beam to convert the first mode into a second mode and narrow the broadened first beam at an output side of the mode converter, wherein the mode converter includes a guide material having a first refractive index and perturbation segments each having a second refractive index, wherein the first refractive index is greater than the second refractive index, wherein the perturbation segments are arranged in the guide material to cross the first beam.

Abstract: An optical fiber with low fictive temperature along with a system and method for making the optical fiber are provided. The system includes a reheating stage that heats the fiber along the process pathway to a temperature sufficient to lower the fictive temperature of the fiber by relaxing the glass structure and/or driving the glass toward a more nearly equilibrium state. The fiber is drawn from a preform, conveyed along a process pathway, cooled and subsequently reheated to increase the time of exposure of the fiber to temperatures conducive to lowering the fictive temperature of the fiber. The process pathway may include multiple reheating stages as well as one or more fiber-turning devices.

Abstract: A resin optical waveguide containing a core, an under cladding and an over cladding having refractive indices lower than that of the core, in which the resin optical waveguide has, at one end side thereof, a core-exposed section at which the over cladding is not present and the core is exposed and, of the under cladding, a portion corresponding to the core-exposed section has a core-neighboring region that satisfies the following (1) and (2): (1) the core-neighboring region is a region whose distance from the core is within x, and x is 5 ?m or more and 20 ?m or less; and (2) the core-neighboring region has a refractive index distribution that the refractive index at a side of an interface with the core is high and the refractive index at a far side from the interface with the core is low.

Abstract: A pine shaped metal nano-scaled grating, the grating including a substrate and a plurality of three-dimensional nanostructures located on the substrate, wherein each three-dimensional nanostructure comprises a first rectangular structure, a second rectangular structure, and a triangular prism structure; the first rectangular structure is located on the substrate, the second rectangular structure is located on the first rectangular structure, the triangular prism structure is located on the second rectangular structure, a first width of a bottom surface of the triangular prism structure is equal to a second width of a first top surface of the second rectangular structure and greater than a third width of a second top surface of the first rectangular structure, and the first rectangular structure comprises a first metal and the triangular prism structure comprises a second metal.

Abstract: A method for making an apparatus, a system, and apparatus, the apparatus and system each comprising a substrate with a top side, wherein the substrate has a set of cavities in the top side of the substrate, wherein the substrate has a set of conductive elements on the top side of the substrate arranged to electrically couple with a set of conductive elements of a photonic integrated circuit (PIC), wherein each cavity of the set of cavities when coupled to the PIC creates a surface tension when exposed to an underfill to cause the underfill to flow around each cavity.

Abstract: Optical coupling of a photonic chip to an external device by use of a system with two lenses. The photonic chip comprises a light guide layer supported by a substrate and covered by an encapsulation layer, and a lens integrated into either the front face or the back face. The light guide layer includes a wave guide coupled to a surface grating coupler. An arrangement of one or several reflecting structures each on either the front face or the back face, is provided. This arrangement comprises a reflecting structure on the back face and is made so as to assure propagation of light between the surface grating coupler, and the lens along an optical path having at least one fold. The invention also covers the fabrication method of such a photonic chip.

Abstract: Apparatus and method for realizing tubular optical waveguides in glass by femtosecond laser direct writing. Irradiation in glass with focused femtosecond laser pulses leads to decrease of refractive index in the modified region. Tubular optical waveguides of variable mode areas are fabricated by forming the four sides of the modified regions with slit-shaped femtosecond laser pulses, ensuring single mode waveguide with a mode field dimension compatible with direct coupling to single-mode optical fibers.

Abstract: A semiconductor photonic device includes a substrate, facet(s), and optical coupler(s) associated with the facet(s). Each optical coupler can couple an electromagnetic field incident on the respective facet towards the substrate as the electromagnetic field proceeds into the semiconductor photonic device. In some examples, each coupler has waveguides extending in a longitudinal direction and at least partly encapsulated within corresponding cladding layers. A first waveguide extends farther from the facet in the longitudinal direction than does a second waveguide. The second waveguide is located farther above the silicon substrate than is the first waveguide. The coupler can include a stack of waveguide assemblies. A lower waveguide assembly can include one waveguide. An intermediate or upper waveguide assembly can include multiple waveguides. In some examples, at least one waveguide tapers along its length.

Abstract: In one aspect, a display comprises a light source, a film-based lightguide with a light emitting region positioned adjacent to and directing light to an active area of a spatial light modulator in a thickness direction. The film may have a light mixing region positioned between a light input region and the light emitting region. In one aspect the display comprises a guide element having a surface curved in a first plane positioned along a first edge of the spatial light modulator, wherein the film is folded along the curved surface at a first fold such that the first fold positions a portion of the light mixing region above or below the active area, the light mixing region comprises the first fold, and an inner surface of the film in the light mixing region is in contact with and curved along the curved surface of the guide element.

Abstract: A modular routing node includes a single input port and a plurality of output ports. The modular routing node is arranged to produce a plurality of different deflections and uses small adjustments to compensate for wavelength differences and alignment tolerances in an optical system. An optical device is arranged to receive a multiplex of many optical signals at different wavelengths, to separate the optical signals into at least two groups, and to process at least one of the groups adaptively.

Abstract: Embodiments herein provide method and apparatus for modifying dimensions of a waveguide. The method includes positioning a shadow mask, with an aperture, above the waveguide, fabricated on a substrate. Further, the method includes spatially filtering, a substance through the aperture in the shadow mask on a portion of the waveguide. Furthermore, the method includes obtaining an adiabatic spot size converter at least at one end of the waveguide by adjusting a distance between the shadow mask and a surface of the waveguide to modify the dimensions of the waveguide.

Abstract: The present disclosure relates to an integrated chip having a multiband transmission and reception elements coupled to an integrated dielectric waveguide. In some embodiments, the integrated chip has a dielectric waveguide disposed within an inter-level dielectric (ILD) structure over a substrate. A multiband transmission element having a plurality of phase modulation elements is configured to generate a plurality of modulated signals in different frequency bands. A plurality of transmission electrodes are located along a first side of the dielectric waveguide and are respectively configured to couple one of the plurality of modulated signals into the dielectric waveguide.

Abstract: Waveguide structures and methods of fabricating waveguide structures. The waveguide structures are formed using a semiconductor substrate that includes a device layer, a handle wafer, a buried oxide layer between the handle wafer and the device layer, and an epitaxial semiconductor layer over the device layer. First and second trench isolation regions extend through the device layer and the epitaxial semiconductor layer. The first and second trench isolation regions are spaced to define a waveguide core region comprising a section of the device layer and a section of the epitaxial semiconductor layer that are arranged between the first and second trench isolation regions. A first airgap and a second airgap are respectively located in the device layer and the buried oxide layer. The first and second airgaps are arranged beneath the waveguide core region, and the first airgap may be arranged between the second airgap and the waveguide core region.

Abstract: An optical transceiver includes a substrate, a transceiver module, an optical lens and a ferrule. The transceiver module is disposed on an outer surface of the substrate. The optical lens includes a supporting portion and at least one extension portion connected to the supporting portion. The extension portion is located between the supporting portion and the substrate. The supporting portion defines a bottom surface facing the outer surface. The bottom surface is spaced apart from the outer surface. The extension portion defines a lateral surface connected to the bottom surface. The bottom surface of the supporting portion, the lateral surface of the at least one extension portion and the outer surface of the substrate jointly form an accommodation groove. The ferrule is disposed in the accommodation groove through an opening of the accommodation groove, and the ferrule is supported by the supporting portion.

Abstract: A wavelength division multiplexer is disclosed. The wavelength division multiplexer may include an input waveguide, in which a plurality of Bragg gratings for separating multiplexed optical signals into respective optical signals are provided, and a plurality of output waveguides connected to the input waveguide and configured to receive the optical signals separated by the plurality of Bragg gratings. The plurality of Bragg gratings may include a first Bragg grating including first protrusions each having a first width, and a second Bragg grating including second protrusions each having a second width larger than the first width. Each of the first and second protrusions may include a curved side surface, to which a corresponding one of the optical signals is incident.

Abstract: The present disclosure relates to an integrated chip having differential coupling elements that couple electromagnetic radiation having a frequency outside of the visible spectrum between a silicon substrate and a dielectric waveguide overlying the silicon substrate. In some embodiments, the integrated chip has a dielectric waveguide disposed within an inter-level dielectric (ILD) material overlying a semiconductor substrate. A differential driver circuit generates a differential signal having a first transmission signal component at a first output node and a complementary second transmission signal component at a second output node. A first transmission electrode located along a first side of the dielectric waveguide receives the first transmission signal component from the first output node, and a second transmission electrode located along a second side of the dielectric waveguide receives the complementary second transmission signal component from the second output node.

Abstract: An optical module includes a first optical block (OB) which is mounted on a substrate and a second OB which holds an optical fiber. When orthogonal X and Z directions are parallel to a substrate surface and a direction orthogonal thereto is a Y direction, the first OB includes a base part and two extending parts which extend in the Z direction. The second OB is configured to be accommodated between the two extending parts from the upper side of the Y direction and to be moved in the Z direction between the two extending parts. Positioning parts for positioning the second OB with respect to the first OB in the X and Y directions are formed on the second OB. An extending direction of the optical fiber held by the second OB is the Z direction and a light traveling direction between the base part and the second OB is the Z direction.

Abstract: This invention relates to assemblies and processes for increasing the bandwidth of differential passive elements. The use of a floating plane in differential transmission lines is disclosed. One such assembly is a broadband balun having high even mode effective impedance, thus degrading the even-mode propagation or matching, and maintaining the desired odd mode effective impedance. Other assemblies can include line couplers, hybrid couplers, RF chokes with back-to-back baluns, and other elements, such as balanced filters.

Abstract: A provided semiconductor device includes a Ge photodiode having proper diode characteristics. A groove is provided on a germanium growth protective film, a p-type silicon layer, and a first insulating film from the top surface of the germanium growth protective film without reaching the major surface of a semiconductor substrate. An i-type germanium layer and an n-type germanium layer are embedded in the groove with a seed layer interposed between the layers and the groove, the seed layer being made of amorphous silicon, polysilicon, or silicon germanium. The i-type germanium layer and the n-type germanium layer do not protrude from the top surface of the germanium growth protective film, thereby forming a flat second insulating film having a substantially even thickness on the n-type germanium layer and the germanium growth protective film.

Abstract: Waveguide connectors include a ferrule having first alignment features. A waveguide has one or more a topclad portions, each with a waveguide core, second alignment features fastened to the first alignment features, and underclad portion that is thicker than the one or more topclad portions.

Abstract: A photonic integrated circuit includes an optical coupling device situated between two successive interconnection metal levels. The optical coupling device includes a first optical portion that receives an optical signal having a transverse electric component in a fundamental mode and a transverse magnetic component. A second optical portion converts the transverse magnetic component of the optical signal into a converted transverse electric component in a higher order mode. A third optical portion separates the transverse electric component from the converted transverse electric component and switches the higher order mode to the fundamental mode. A fourth optical portion transmits the transverse electric component to one waveguide and transmits the converted transverse electric component to another waveguide.

Abstract: The present invention discloses a TEOS with a high extinction ratio based on slab PhCs which comprises an upper slab PhC and a lower slab PhC connected as a whole; the upper slab PhC is a first square-lattice slab PhC, the unit cell of the first square-lattice slab PhC includes a high-refractive-index rotating-square pillar, three first flat dielectric pillars and a background dielectric, the first flat dielectric pillars include a high-refractive-index dielectric pipe and a low-refractive-index dielectric, or 1 to 3 high-refractive-index flat films, or a low-refractive-index dielectric; the lower slab PhC is a second square-lattice slab PhC with a complete bandgap, the unit cell of the second square-lattice slab PhC includes a high-refractive-index rotating-square pillar, three second flat dielectric pillars and a background dielectric is a low-refractive-index dielectric; and an normalized operating frequency of the TEOS is 0.4057 to 0.406.

Abstract: A covering film adapted to a keyboard module is provided. The covering film includes a semi-translucent layer. The semi-translucent layer has a plurality of first pressing regions and covers the keyboard module. The first pressing regions are aligned to a plurality of input regions of the keyboard module respectively, and each of the first pressing regions has a patterned indentation. In addition, an electronic device having the covering film is also provided.

Abstract: Areas having different isotopic ratios are artificially introduced into a metal material before sintering, a heat treatment, or grain boundary diffusion, and atom probe analysis results before and after sintering, a heat treatment, or grain boundary diffusion are compared to evaluate a change in isotopic distribution over time.

Abstract: A disclosed optical device includes a first waveguide disposed between a branching portion and a multiplexing portion on a semiconductor substrate, and a second waveguide disposed between the branching portion and the multiplexing portion, the second waveguide being longer than the first waveguide. In the optical device, an optical confinement effect of the first waveguide is greater than an optical confinement effect of the second waveguide, the first waveguide has a curvature with a first curvature radius (Rs), the second waveguide has a curvature with a second curvature radius (Rl), and the first curvature radius is smaller than the second curvature radius.

Abstract: A system includes an encoding circuit, a line quality monitor circuit, and a controller circuit. The encoding circuit generates a first data signal indicating encoded data using a first forward error correction code. The line quality monitor circuit generates an indication of a line quality of a second data signal using an eye monitor circuit that monitors the second data signal. The controller circuit causes the encoding circuit to generate encoded data in the first data signal using a second forward error correction code in response to a change in the indication of the line quality of the second data signal.

Abstract: In one aspect, a light emitting device comprises a light source, a film-based lightguide with a light emitting region. The film may have a light mixing region positioned between a light input region and the light emitting region. In one aspect a ratio of a length of the light mixing region to a length of the light emitting region is greater than 0.1 in a first plane comprising the thickness direction. In one aspect the light emitting device comprises a guide element having a surface curved in a first plane positioned adjacent the inner surface of the film, wherein the film is folded along the curved surface at a first fold such that the first fold positions a portion of the light mixing region above or below the active area of the display and the light mixing region comprises the first fold.

Abstract: Techniques are provided for making a funnel-shaped nozzle in a substrate. The process can include forming a first opening having a first width in a top layer of a substrate, forming a patterned layer of photoresist on the top surface of the substrate, the patterned layer of photoresist including a second opening, the second opening having a second width larger than the first width, reflowing the patterned layer of photoresist to form curved side surfaces terminating on the top surface of the substrate, etching a second layer of the substrate through the first opening in the top layer of the substrate to form a straight-walled recess, the straight-walled recess having the first width and a side surface substantially perpendicular to the top surface of the semiconductor substrate.

Abstract: A display may have an array of pixels that display images for a user. The backlight unit may have a light-guide layer. An array of light-emitting diodes may emit light into an edge of the light-guide layer. The light guide layer may overlap a backlight reflector. A quarter wave plate may be interposed between the light guide layer and the backlight reflector. A turning film may be interposed between a lower polarizer in the array of pixels and the light guide layer. The lower polarizer may be a reflective polarizer. Light exiting the upper surface of the turning film may have a dominant polarization. A half wave plate may be used to rotate the dominant polarization into alignment with a pass axis of the reflective polarizer.

Abstract: Semiconducting quantum dots are applied to a fluid. The quantum dots are configured to absorb visible or near infrared light and re-radiate infrared energy that excites a fundamental vibration frequency of the fluid.

Abstract: A disclosed electrical cell enables experimental measurements of dielectric properties of an electrochromic material in the radio-frequency range of the electromagnetic spectrum. In an example embodiment, the electrical cell includes a layer of the electrochromic material under test that is sandwiched between a conducting base plane and a microstrip line. The conducting base plane and the microstrip line are electrically connected to a co-planar waveguide configured for application of superimposed DC-bias and RF-probe signals using a conventional probe station and a vector network analyzer. The S-parameters of the electrical cell measured in this manner can then be used, e.g., to obtain the complex dielectric constant of the electrochromic material under test as a function of frequency.

Abstract: Provided is an optical coupler including a substrate, a buffer layer on the substrate, a ridge waveguide having a first side surface and a second side surface opposed to the first side surface, and a first waveguide disposed adjacent to the second side surface. The first waveguide includes a first body part and a first connecting part extending from one end of the first body part to be inserted in the ridge waveguide. The first connecting part has a width decreasing in the direction away from the second side surface, and the ridge waveguide includes an extension part extending under an upper surface of the buffer layer.