1236 results about "Light propagation" patented technology

Optical gain of a nonpolar or semipolar Group-III nitride diode laser is controlled by orienting an axis of light propagation in relation to an optical polarization direction or crystallographic orientation of the diode laser. The axis of light propagation is substantially perpendicular to the mirror facets of the diode laser, and the optical polarization direction is determined by the crystallographic orientation of the diode laser. To maximize optical gain, the axis of light propagation is oriented substantially perpendicular to the optical polarization direction or crystallographic orientation.

A method for calibrating a pulse oximeter device and an apparatus incorporating the method and a system for utilizing the method. The method is based on modeling light propagation in tissue at two wavelengths, typically, one in the red and one in the infrared range of the spectrum. A formula is derived relating the arterial oxygen saturation to a ratio R commonly measured by standard pulse oximeters. A specific parameter is identified and utilized in the calibration of the oximeter. This parameter is formulated in terms of the DC signals measured by the pulse oximeter at the two wavelengths. An empirical method for estimating this parameter based on experimental data is also described.

An image projection system and method are presented to project an image on at least one of first and second projection planes. The system comprises a light source system including one or more light source assemblies operable to generate light of one or more predetermined wavelength range; a spatial light modulator (SLM) system including one or more SLM units operable to spatially modulate input light in accordance with an image to be directly projected or viewed; and two optical assemblies associated with two spatially separated light propagation channels, respectively, to direct light to, respectively, the first and second projection planes with desired image magnification. The system is configured to selectively direct the input light propagating towards the SLM system or light modulated by the SLM system to propagate along at least one of the two channels associated with the first and second projection planes, respectively.

Structured screens for the controlled spreading, diffusion, or scattering of an incident beam are provided. The screens are composed of microstructures (1,2) whose configurations and distribution on the surfaces of the screen are precisely determined. In certain embodiments, the configurations and / or their distribution is randomized. The structured screens can be used as diffusing screens or display screens.

A display device is mounted on and / or inside the eye. The eye mounted display contains multiple sub-displays, each of which projects light to different retinal positions within a portion of the retina corresponding to the sub-display. The projected light propagates through the pupil but does not fill the entire pupil. In this way, multiple sub-displays can project their light onto the relevant portion of the retina. Moving from the pupil to the cornea, the projection of the pupil onto the cornea will be referred to as the corneal aperture. The projected light propagates through less than the full corneal aperture. The sub-displays use spatial multiplexing at the corneal surface. Various electronic devices interface to the eye mounted display.

Method for real-time computing of indirect illumination in a computer graphics image of a scene, comprising: defining a light propagation volume as a three-dimensional grid consisting of a plurality of grid cells; allocating a plurality of secondary light sources to grid cells of said light propagation volume; accumulating directional, colored irradiance contributions of all secondary light sources in a respective grid cell and repeating this step of accumulating for all grid cells of the light propagation volume to thereby obtain an initial indirect light intensity distribution. The propagation of light in said light propagation volume is then iteratively computed starting with the initial indirect light intensity to obtain a final indirect light intensity distribution, which is used for rendering the scene illuminated by the final indirect light intensity distribution during a usual scene rendering process from a camera's point of view.

A light emission device capable of holding a uniform color in various environments. A light source control device has a light detection device for detecting emission brightness of light sources that emit different colors and controlling emission brightness of at least one light source of the light sources based on the detection result of the light detection device. A through-hole is formed in a reflection member for reflecting light emitted from the light source, and the reflection is in a predetermined direction. The light detection device is provided across the reflection member from the light source, and the light propagation member is provided at the through-hole.

Light emitting diodes are prepared with specialized packages which provide a dosing feature with respect to a phosphor wavelength converting medium. Elements of the device package form a specially shaped cavity when coupled together. The shape and size of the cavity operates to control the dosing of phosphor spiked medium of soft gel. The gel fills the cavity such that light emitted from a semiconductor die is exposed to a similar cross section independent of the exact direction of light propagation. In this way, 'white' LED systems are formed from blue emitting diodes as highly controlled phosphor dosing permits precise amounts of blue light to be converted to yellow light without problems with angular uniformity observed in competing technologies.

A face-lit waveguide illumination system employing a planar slab or plate of an optically transmissive material. A light source is optically coupled a linear optical element which is attached to a face of the waveguide and is configured to inject light at an angle permitting for light propagation by means of a total internal reflection. Light is propagated through the waveguide towards a predetermined direction in response to optical transmission and total internal reflection. Light extraction features located along the prevailing path of light propagation extract light from the waveguide and emit such light towards a surface perpendicular. In one embodiment, the planar waveguide includes a window pane which provides light transport from one location, where light is injected through the face of the pane, to another location where light is extracted. Additional embodiments of the face-lit waveguide illumination system are also disclosed.

Systems, methods, and apparatuses of low-coherence enhanced backscattering spectroscopy are described within this application. One embodiment includes providing incident light comprising at least one spectral component having low coherence, wherein the incident light is to be illuminated on a target object in vivo. An intensity of one or more of at least one spectral component and at least one angular component of backscattering angle of backscattered light is recorded, wherein the backscattered light is to be backscattered from illumination of the incident light on the target object and wherein the backscattering angle is an angle between incident light propagation direction and backscattered light propagation direction. The intensity of the at least one spectral component and the at least one backscattering angle of backscattered light is analyzed, to obtain one or more optical markers of the backscattered light, toward evaluating said properties.

A backlight unit has a light source, a reflection sheet, a light guide plate, an air space, and a diffuser, wherein the reflection sheet, the light guide plate, the air space, and the diffuser are overlaid in this order. The light source is configured to arrange individual light sources having different spectra or different light emission quantities near an incident plane of the light guide plate, and on a plane facing the reflection sheet of the light guide plate, scatter dots are disposed which take light propagating through the light guide plate out of the reflection sheet side. The backlight unit and a liquid crystal display device including the same have excellent display quality.

Multi-core optical fiber probe includes a multi-core optical fiber (and method of manufacturing the probe) including a plurality of cores adjacent a cladding material, and a plurality of angled reflectors disposed at a distal end of the cores. An angled reflector of the plurality of angled reflectors deflects light propagating in the core at a deflection angle that is different from an axis of light propagation in the core. Light propagating toward a distal end of the core of the multi-core probe is emitted, after reflection by the corresponding reflector, out of the multi-core optical fiber probe.

A touch-sensitive apparatus comprises a light transmissive panel, an illumination arrangement and a detection arrangement. The illumination arrangement is configured to couple light into the panel via an incoupling site such that the light propagates by total internal reflection in opposite top and bottom surfaces of the panel and such that an object touching the top or bottom surface causes a change in the propagating light. The detection arrangement comprises a light detector arranged to detect the change in the propagating light. A compact and robust incoupling site is defined by a sheet-like micro-structured surface portion which is fixedly arranged on one of the top and bottom surfaces and configured to transmit light having an angle of incidence that enables light propagation by TIR inside the panel.

Power scalable, rectangular, multi-mode, self-imaging, waveguide technologies are used with various combination of large aperture configurations, 20, 50, 80, 322, 324, 326, 328, 330, 332, 334, 336, 338, Gaussian 360 and super-Gaussian 350 beam profiles, thermal management configurations 100, flared 240 and tapered 161 waveguide shapes, axial or zig-zag light propagation paths, diffractive wall couplers 304, 306, 308, 310, 312, 314, 316, 318, 320 and phase controller 200, flexibility 210, phased arrays 450, 490, beam combiners 530, 530′, and separators 344, 430, and other features to generate, transport, and deliver high power laser beams.

A modular luminaire which uses LED light sources. The basic frame comprises two end pieces compressed together by through bolts. At least one elongated heat sink is compressed between the end pieces. Each heat sink may bear a plurality of LEDs mounted on a printed circuit board which may have an integral metallic backplate, and is installed on one of the heat sinks with a layer of heat conductive grease therebetween. The heat sinks have fins projecting in three directions, the fourth direction being accounted for by the LEDs, and are rotatable about their longitudinal axes to adjust direction of light propagation. The heat sinks are arrayed in an arc, so that the outside heat sinks shield observers from direct glare from opposed heat sinks. Heat sinks may be extruded to form cooling fins and slots which may receive fasteners such as screws.

An elongated LED lighting arrangement comprises an elongated fiberoptic light pipe having an exteriorly facing sidewall between its ends. The light pipe is constructed to promote TIR of light between the ends. A first LED light source is tuned to efficiently provide light within a wavelength range to the pipe. Light-extracting means are applied along the light pipe along the main path of TIR light propagation, and comprise down-converting means tuned to efficiently convert light rays from the LED light source within the wavelength range to lower-energy light rays at respectively longer wavelengths and light-scattering means for extracting from the pipe some light rays within the wavelength range without changing the wavelengths of the foregoing light. The light emitted by the down-converting means and the light-scattering means intermix to produce light, the majority of which has a composite color determined by the foregoing light emitted and the foregoing light extracted.

A system for the rapid analysis of microbiological parameters includes a specimen container for containing a liquid sample, a housing having an enclosable chamber shaped for receiving the specimen container, an incubating system mounted within the housing for incubating microbiological materials within the liquid sample, and a spectrophotometer system mounted within the housing for measuring light absorbed, emitted or scattered by the liquid samples as the microbiological materials are incubated by the incubating system over time. The specimen container is filled with a liquid sample to be tested and mixed with a reagent that provides a detectable parameter, and placed inside the apparatus. The incubation system heats and maintains the temperature of the liquid sample within a preset range while the spectrophotometer system propagates light within the specimen container, and monitors and records changes in the light as the light propagates through the container. A continuous non-intrusive monitoring and recording of the test parameter is achieved as the incubation progresses. Any significant deviation of the signal output is an indication of presence of the detectable parameter, while the time taken to reach the significant deviation provides quantification of the microbiological parameter under investigation.

An optical waveguide having a optical waveguide path capable of securing a high light propagation characteristic regardless of the type of a supporting base, provided with a multilayer circuit board, an optical waveguide path arranged on the multilayer circuit board, a light receiving element, IC chips, and a light emitting element, the optical waveguide path formed on a transparent substrate excellent in flatness and transferred to the multilayer circuit board. The light propagation loss becomes small, and a signal to be transmitted at a high speed being transmitted as a light signal and a signal which can be transmitted at a relatively low speed being transmitted as an electrical signal, whereby the signal propagation delay which becomes the problem when a signal is transmitted by only electrical wiring is overcome, and the influence of electromagnetic noise becomes small.

Electronically agile optical filtering modules for equalizing light propagation differences in at least two spaced optical beam pathways in the modules. The modules use optical polarization rotation devices that may include acousto-optic tunable filter (AOTF) devices, liquid crystal devices, and magneto-optic devices. Such devices may be subject to polarization dispersion losses (PDL) and polarization mode dispersion (PMD) that may be different for when light travel along different light paths through the device. By redirecting light beams back along a different bi-directional path through the devices which may exhibit non-uniform performance across orthogonal polarizations, PDL and PMD may be reduced.

A measurement apparatus is configured to measure a spectroscopic characteristic of a measurement site in a specimen by applying acousto-optical tomography. The measurement apparatus includes a measurement unit configured to measure a light intensity of each of measurement areas that are set differently from the measurement site on a light propagation path from the measurement site to a detection position of a light detector and a signal processing device configured to sequentially modify the spectroscopic characteristics of the measurement areas and the measurement site on the light propagation path from the detection position of the light detector to the measurement site by using a light intensity that is measured by the measurement unit in the measurement area that is closer to a surface layer of the specimen than the measurement site.

To protect tissue in the treatment of an eye (3) with a focused pulsed laser beam (21) generated by a laser system (2), e.g. a femtolaser system, operating data which define an operating area operated on by the focus (F) of the laser beam (21) during the treatment are acquired in a device (1). The device (1) comprises a processing module (14) for providing control data for the laser system (2) on the basis of the operating data and taking into consideration the light propagation in the eye. The control data limit the time of the treatment by the focus (F) at positions within the operating area in each case in such a manner that tissue damage resulting from the treatment by the laser beam (21) is essentially prevented in eye structures located outside the operating area. In particular, the control data determine movements of the focus (F) within the operating area and / or the activity of the laser beam (21) in such a manner that the mean irradiation intensity is reduced and the maximum temperatures in the tissue of eye structures located outside the operating area, particularly in the iris and the retina, are reduced.

A touch-sensitive apparatus operates by light frustration (FTIR) and comprises a light transmissive panel (1) with a front surface (5) and a rear surface (6). Light emitters (2) and light detectors are optically coupled to the panel (1) to define a grid of light propagation paths inside the panel (1) between pairs of light emitters (2) and light detectors. A light in coupling structure comprises a diffusively reflective element (20) on the rear surface (6) and a specularly reflective element (22) on the front surface (5). Each light emitter (2) is arranged to project a beam of light onto a transmissive surface portion (24) on the rear surface (6), such that at least a portion of the beam of light enters the light transmissive panel (1) through the transmissive surface portion (24), is specularly reflected against the specularly reflective element (22) and impinges on the diffusively reflective element (20) from inside the light transmissive panel (1).

A light guide includes a light guide layer having a transversely oriented side-end surface that forms a primary output aperture (exit) for light traveling in a forward propagation direction out of the end surface of the light guide (for, e.g., CPV applications) and, which forms a primary input aperture (entrance) for light traveling in a rearward propagation direction into the end surface of the light guide (for, e.g., illuminator applications), and a first plurality of light injection elements stepped (staggered) in a forward light propagation direction in a first plane along lines parallel to the side-end surface or clocked (tilted) about a y-axis in a z-axis-light propagation direction in a respective first plane, wherein the light injection elements are disposed along parallel lines normal to the side-end surface. The light guide component may further comprise at least a second plurality of light injection elements stepped in at least second plane. A light guide system includes a component light guide, a lenslet array disposed adjacent a top surface of the light guide, and a light-transmitting, TIR medium layer disposed immediately adjacent at least one of the top and bottom surfaces of the light guide.