111 results about "Diffuse illumination" patented technology

The systems and methods disclosed herein relate to sources of diffuse illumination for providing substantially uniform illumination to a surface. The diffuse illumination arises from varying the diffusion angle of light generated by an LED system. To vary the diffusion angle, a translucent member is placed between the LED system and the surface. Light emitted from the LED system across the translucent member can subsequently can uniformly cover the surface.

An illumination system and method for use in a handheld symbology reader that employs a grid of reflecting elements applied to a transparent plate adapted to project a highly diffuse and uniform illumination on a subject. The grid defines a geometry with a large number of transparent spaces between grid elements through which an image of the subject can be acquired. A light source array is configured to project light into the grid at a right angle via a light pipe having a distal beveled edge or side projecting light sources. Another light source may be employed to illuminate second light pipe with a chamfered edge to create low-angle illumination.

A hand held industrial identification symbol reader projects diffuse illumination onto a region of interest to produce high contrast images of symbols. The diffuse illumination is particularly well suited for producing images of symbols that are marked directly on objects. The diffuse illumination is created through the use of an optically translucent diffuser having a generally tapered shape that distributes diffuse illumination throughout the field of view of the reader. The diffuse illumination can be supplemented with dark field illumination using selectively actuated illumination sources.

This invention provides a system and method for employing and analyzing images that are illuminated in different colors depending upon the type of illumination being employed. In an illustrative embodiment, a color image sensor is used to acquire images of subjects of interest, and each of the direct bright field, dark field and diffuse illumination are transmitted to the surface simultaneously (concurrently with each other) in a discrete illumination color that is discretely discernable by the sensor. For example, direct bright field and dark field may be red, while diffuse may be blue. Pixels of the same sensitivity (for example, red and blue) in the image sensor receive only the image generated by that color of illumination. The reader of this invention includes processing components that independently assemble images from red and blue pixel addresses to create, in effect two simultaneous images (one image generated using a combination dark field and direct bright field and the other image generated using diffuse illumination) that overlap (are registered with respect to each other) perfectly. The best image is determined using conventional image analysis tools, and meaningful data (the code of the read symbol, for example) is derived from that best image.

The backlight system of the invention creates illumination behind a liquid crystal or other transparent display. In one mode of operation it produces a series of precise, thin slanted lines with dark space in between which are used to make multiple perspective views, displayed simultaneously on the LCD, visible from a series of horizontally spaced viewing zones spaced in front of the display. In another mode of operation, it produces even diffuse illumination similar to that generated by conventional backlights, allowing the LCD to display conventional 2D images.

An inspection station (6) has a ring of 370 nm LEDs (24) for low-angle diffuse illumination of flux. This stimulates inherent fluorescent emission of the flux without the need for flux additives or pre-treatment. A CCD sensor (20) detects the emission. An image processor generates output data indicating flux volume according to a relationship between emission intensity and volume over the surface of the flux. Intensity non-uniformity indicates either height non-uniformity or hidden voids, both of which give rise to defects after application of solder paste and reflow. The inspection is particularly effective for pre solder application flux inspection.

This invention provides a system and method for employing and analyzing images that are illuminated in different colors depending upon the type of illumination being employed. In an illustrative embodiment, a color image sensor is used to acquire images of subjects of interest, and each of the direct bright field, dark field and diffuse illumination are transmitted to the surface simultaneously (concurrently with each other) in a discrete illumination color that is discretely discernable by the sensor. For example, direct bright field and dark field may be red, while diffuse may be blue. Pixels of the same sensitivity (for example, red and blue) in the image sensor receive only the image generated by that color of illumination. The reader of this invention includes processing components that independently assemble images from red and blue pixel addresses to create, in effect two simultaneous images (one image generated using a combination dark field and direct bright field and the other image generated using diffuse illumination) that overlap (are registered with respect to each other) perfectly. The best image is determined using conventional image analysis tools, and meaningful data (the code of the read symbol, for example) is derived from that best image.

The present invention discloses an apparatus and method for color measurement and color grading of faceted gemstones, diamonds and the like. The apparatus comprises a spectrometer, a computer, and a dual integrating sphere measurement arrangement comprising a measurement integrating sphere, a sample integrating sphere, a sample platform, a filter, a lens system, a baffle and a light source. The measurement geometry of the dual integrating sphere measurement arrangement is diffuse illumination and 8 degree viewing with the specular component excluded, plus diffuse white background provided by the sample integrating sphere. The sample integrating sphere encloses a sample to provide a constant environment for simulating the visual color grading environment. A novel three-step calibration insures an accurate spectral measurement of the sample inside the measurement integrating sphere. The computer controls the spectrometer and provides measurement parameters calculated from the physical parameters of the measured sample, including, but not limited to, shape, dimensions, refractive index, intensity of fluorescence and cut grade. The computer then calculates the spectral reflectance and calorimetric data, and determines an average color grade by checking a look-up-table that represents the relationship between the CIELAB coordinate and the average color grade. The computer also determines a true color grade based upon the average color grade and the physical parameters, using mathematical analyses and algorithms.

A combination light and sound producing fixture is disclosed for installation in a wall or ceiling or on a wall or ceiling. The sound producing elements is an arrangement of speakers having a low frequency transducer and one or more high frequency transducers oriented directed to emit sound in a particular direction. The fixture may further include digital signal processing to modify the sound to account for obstructions in near or around the fixture. The fixture may include a feedback system that allow the fixture to self modify its frequency response. The signal to the fixture is provided by wired or wireless interface. The surface of the sound transducer can be reflective in nature to provide focusing or diffusion of the light from the lighting elements. The lighting elements are incandescent, fluorescent or low voltage LED type that may include adjustment for lighting intensity or color.

A backlight device that illuminates a transmissive liquid crystal panel is disclosed. The device includes: a plurality of light source substrates on which a plurality of light emitting devices irradiating illumination light are mounted; drive substrates having drive circuits for the light emitting devices and electrically connected to the light source substrates; a bottom chassis having one surface to which the plurality of light source substrates are attached; a reflector having openings corresponding to the light emitting devices and through which the light emitting devices are exposed, and reflecting the illumination light; a diffuser facing the one surface side of the reflector through a predetermined facing interval and internally diffusing the illumination light; and an optical function sheet laminate combined with the diffuser on one surface side thereof, containing a stack of a plurality of optical function sheets and guiding the illumination light to the liquid crystal panel.

An illumination optical system disposed in order to diffuse illumination light emitted from a light source, includes at least one optical device having a roughened optical surface, with the arithmetic average roughness of the roughened surface set in a range of 0.05 to 0.75 [μm].

A diffusive illuminator is provided. The diffusive illuminator includes a set of light sources and a light guiding structure including a plurality of layers. At least some of the layers can be formed of a fluoropolymer and at least one layer can be formed of a transparent fluid. The light guiding structure also includes an emission surface through which diffused light exits. The light guiding structure can further include diffusive elements associated with at least one of the plurality of layers. Each diffusive element can diffuse the light to within forty percent of Lambertian distribution. The diffusive elements can be arranged based on a desired uniformity of the diffused light at a target distance corresponding to a surface to be illuminated. The diffusive illuminator can emit ultraviolet light, and can be implemented as part of a disinfection system.

The invention relates to a method to and a computer program product for lighting a computer graphics image to be rendered. It is assumed that a plurality of light sources illuminate one or more objects of the scene to be rendered thus causing a complex lighting situation. For reducing the complexity of the lighting situation and saving computing time the lighting condition is pre-calculated by approximating at least two and preferably all light sources by a single fictitious light source in a pre-calculating step. In the step of pre-calculating, there is computed an approximated light direction for at least two selected ones of the light sources and an approximated light color for the selected light sources by weighting color contributions thereof. The step of pre-calculating is performed for selected areas of a surface of objects present in the scene and results in coefficients that are stored, for these selected areas, in a lightmap or in vertices representing the object surface. The coefficients are retrieved by subsequent method steps for rendering the computer graphics image using the approximated light condition. The invention applies not only to diffuse lighting but is, with a minor modification, also of use for calculating specular lighting.

Performance of an imaging reader for electro-optically reading direct part markings on workpieces is enhanced by uniformly illuminating the markings. An illuminator is operative for emitting illumination light of greater and lesser intensity toward the indicia. A diffuser is operative for diffusing the illumination light en route to the indicia. The diffuser includes a plurality of diffusing elements adjacent the illuminator for diffusing the illumination light of greater intensity more than the illumination light of lesser intensity.

A scatter shutter is used to alternately provide non-scattered illumination for autofocus purposes and diffuse illumination for imaging purposes in a microscope system for high-throughput testing of protein samples in a multi-well tray. As the tray is being scanned continuously through the microscope objective for data acquisition, the scatter shutter is intermittently deactivated to allow collimated light to focus on the underside of the tray and produce autofocus signals, and then activated to produce diffused light and to image the protein sample in each well. The timing of each step is synchronized so as to place the droplet in focus prior to energizing the scatter shutter and switching to the imaging mode.

In the present invention, a method and apparatus are implemented for inspecting the surfaces of ceramic tableware / pieces of ceramic crockery, said method and apparatus being characterized in that, with a single item of equipment: A—the product is illuminated by overall or zone-by-zone diffuse illumination; and B—the product is observed using one or more observation means, by causing the overall diffuse illumination or the localized diffuse illumination from at least one diffuse illumination zone adapted to make at least a selected portion of the product shiny to reflect off said product towards said one or more observation means. The invention makes it possible, with a single piece of apparatus, to show and to identify the defects, whatever they may be, using methods that are “multi-purpose” and fully effective even in critical cases, such as a combination of complex shapes, of shininess, and of white-on-white defects, unlike the prior art.

Methods for rendering a 3D object includes determining incident illumination for object surface points, determining surface colors associated with these points, determining diffuse illumination values associated with these points, associating a 3D grid having vertices the object, determining input scattering values for the vertices from the incident illumination and the surface colors associated with these points, low pass filtering the input scattering values to determine modified scattering values for the vertices, determining output scattering values for these points from the modified scattering values for the vertices, and determining reflected illumination values for these points from the output scattering values, surface material colors, and incident illumination for these points

The present invention provides methods, apparatus and systems for enabling real-time lighting of 3D geometric models. While these are well-suited for all processors, these are particularly useful on low power processors typically found in PDAs, cell phones, and embedded display systems. Methods+presented utilize a preprocessing scale factor and real-time shift factor to efficiently calculate diffuse lighting intensities for the bound vertices of the geometric model. An example embodiment includes scaling first digitized data of a 3D model in a floating point datatype by a scaling factor to form scaled digitized data. The scaling factor being a proper power of two. Converting said scaled digitized data into an integer datatype forming second digitized data. Enabling a transfer of said second digitized data to a display system, and facilitating lighting and shading said second format of digitized data.

Polarization preserving front projection screens and diffusers provide optimum polarization preservation for stereoscopic 3D viewing, as well as improved light control for enhanced brightness, uniformity, and contrast for both 2D and 3D systems. Generally, the disclosed screens direct light from a projector toward viewers within a diffusion locus, while maintaining optimum gain characteristics. More specifically, light incident on a region of the front projection screen from a predetermined projection direction is reflected by an engineered surface to a predetermined diffusion locus after undergoing substantially single reflections. The engineered surface, comprised of generating kernels, is used to optimally diffuse illumination light into a range of viewing angles, within the diffusion locus, with suitable gain profile, while optimally preserving polarization for 3D applications. Such a screen, when combined with matched polarization analyzing eyewear, provides extremely low cross-talk from any observation point.

A non-opaque radiator grille is deployed on an automotive vehicle. The use of non-opaque materials enables the radiator grille to incorporate a variety of different features for styling distinctions, including low visibility illumination, frosting, graphics, ribbing, fluting or other texturing. The grille can be treated or textured on an interior surface of the material to provide the desired textured look, instead of on the exterior surface. The non-opaque grille can be liquid filled, sand blasted and / or incorporate luminescence or diffused lighting. A single grille configuration can be treated internally to provide different styling looks for model or series differentiations. The non-opaque nature of the grille material opens the grille for sensing technology to be incorporated directly into the grille. If secondary external treatment processes are still desired, the use of the non-opaque materials would not prevent the chroming or painting of the radiator grilles.

An arrangement for optically measuring the surface of an optionally glossy target object, includes: a diffusive, semi-transparent illumination structure defining a hollow surface shape configured to surround the target object at least partially, the surface being further provided with at least two apertures, a number of light sources optically coupled to the diffusive illumination structure for illuminating the target object via the surface of the illumination structure, at least two imaging devices, each configured to image the target object via an aperture, and a control entity configured to instruct the number of light sources to form a sequence of predetermined illumination patterns illuminating the target object, to instruct the at least two imaging devices to obtain an image of the target object relative to each illumination pattern, and to derive, through the utilization of the patterns utilized and images obtained, a predetermined surface-related property of the target object.

A system for providing diffuse light to a dial plate of a meter is disclosed. The system includes a light-guide and a light source. The light from the light source enters the light-guide and exits the light-guide to illuminate a curved peripheral portion of a dial plate with a diffuse light.

Performance of an imaging reader for electro-optically reading direct part markings on workpieces is enhanced by uniformly illuminating the markings. An illuminator is operative for emitting illumination light of greater and lesser intensity toward the indicia. A diffuser is operative for diffusing the illumination light en route to the indicia. The diffuser includes a plurality of diffusing elements adjacent the illuminator for diffusing the illumination light of greater intensity more than the illumination light of lesser intensity.

The invention discloses a spectrophotometer for the chromaticity detection of laser paper and belongs to the technical field of optical detection instruments. In the spectrophotometer disclosed by the invention, the spherical surface of a diffused lighting integrating sphere is provided with a sample reflecting hole, an incident hole of the diffused lighting integrating sphere and an exit hole of the diffused lighting integrating sphere; the spherical surface of a diffused accepting integrating sphere is provided with an incident hole of the diffused accepting integrating sphere and an exit hole of the diffused accepting integrating sphere; the exit hole of the diffused lighting integrating sphere and the incident hole of the diffused accepting integrating sphere are same in diameter and are in butt joint with each other; and the sample reflecting hole is connected with a laser paper sample, a flat-filed concave grating is arranged in front of a light path of the exit hole of the diffused accepting integrating sphere, a photoelectric converter, namely a linear array CCD (charge coupled device) is arranged in front of a dispersive light path of the flat-filed concave grating, and the electrical signal output end of the linear array CCD is connected with a signal processing system. The spectrophotometer disclosed by the invention is reasonable in design, simple in structure, and convenient in use, and can be used for correctly measuring the surface spectral reflectances and colorimetric values of all types of laser paper.

A face imaging device capable of imaging a face from plural directions under the same imaging condition, capable of illuminating the face at uniform brightness and capable of obtaining a clear image without causing halation in the image. A face imaging device has an illumination light source (L) provided in a housing (2) in the front of which an opening (6) for inserting a face (3) as the imaging object is formed; a light diffusion plate (7) for diffusing illumination light to illuminate the front side of the face (3) and provided between the opening and the illumination light source (L); an imaging camera (4) provided behind the light diffusion plate (7); a head section supporting member (9) whose position is adjustable in forward-backward and left-right directions and against which a head top side non-observation region of the face (3) is pressed to restrict the position of a head section; a chin placement base (10) for restricting the position of the chin depending on an imaging direction such that the front of the face (3) and left and right cheeks face straight toward the imaging camera (4); and a light shielding body (15) between the illumination light (L) and the imaging camera (4).

An illumination device includes a light output unit having an output end; an optical member that is disposed in a circumferential direction centered on a predetermined axis and that receives illumination light output from the output end and outputs the illumination light from a surface thereof; and a reflective layer that is provided adjacent to an inner side surface of the optical member and that reflects the illumination light outward in the radial direction. The optical member includes a light guide layer that receives the illumination light from the output end and that guides the illumination light and a diffusion layer that is located outside the light guide layer in the radial direction and at one end of the light guide layer in a direction along the axis and that receives the illumination light from the light guide layer and guides the illumination light while diffusing the illumination light.

An ophthalmic glare tester for evaluating visual acuity under conditions of strong diffuse illumination is designed for convenient mounting on a conventional ophthalmic instrument such as a transilluminator or ophthalmoscope. The glare tester incorporates a generally concave reflector for providing diffuse illumination to an eye and a mounting for attachment to an ophthalmic instrument. The reflector includes a wall having an interior light-reflecting surface at least partially enclosing a hollow interior. The glare tester provides for conducting illumination from the ophthalmic instrument to the interior light reflecting surface of the reflector.