Abstract: A liquid crystal display device includes: a liquid crystal panel outputting an image; a light guide plate installed below the liquid crystal panel to transfer light from a backlight unit to the liquid crystal panel; a plurality of optical sheets installed between the liquid crystal panel and the light guide plate; a reflective plate installed below the light guide plate; and a viewing angle control sheet installed between the liquid crystal panel and the optical sheet and having a diffractive pattern formed on an upper surface of a base film and a prism pattern formed on a lower surface of the base film to control a viewing angle.

Abstract: A liquid crystal display device includes a liquid crystal display panel, and a backlight of an edge light system. The backlight includes a light source, and a light guide plate that has a light emitting surface for emitting a light input from the light source into a planar shape, and is placed on the liquid crystal display panel. The light source is located to face an end surface of the light guide plate on a side of the liquid crystal display panel so as not to overlap with the liquid crystal display panel.

Abstract: A liquid crystal display device includes: a bottom frame having a bent portion at an edge thereof; a light guide plate over the bottom frame, the light guide plate spaced apart from the bent portion by a gap; a light emitting diode (LED) assembly facing a side of the light guide plate, the LED assembly fixed to the bent portion; a main frame having a rectangular band shape over the bottom frame, the main frame having a rib corresponding to the gap; a liquid crystal panel over the light guide plate; and a top frame surrounding a front boundary portion of the liquid crystal panel, the top frame combined with the bottom frame and the main frame.

Abstract: A white light emitting diode includes a blue light emitting diode (“LED”) light source, and a light conversion layer which converts incident light from the blue LED light source into white light. The light conversion layer includes a green light emitting semiconductor nanocrystal and a red light emitting semiconductor nanocrystal. The white light emitting diode has a red, green and blue color (“RGB”) color locus which is within a chrominance error range (±4?E*ab) locus from the constant hue locus of each of sRGB color coordinates, or within a chrominance error range (±4?E*ab) locus from the constant hue locus of each of AdobeRGB color coordinates.

Abstract: A backlight unit for a display device includes a light source module which emits light, a light guiding plate which guides the light incident from the light source module toward a front surface thereof, and a light beam spread angle regulating sheet disposed between the light source module and a lateral surface of the light guiding plate, where the light beam spread angle regulating sheet regulates a light beam spread angle of the light incident from the light source module.

Abstract: Provided is a lighting device (3) that includes a light guide plate (10) having a light entry surface (10a) through which the light originating from a light-emitting diode unit (9) enters, and a light-emitting surface (10c) from which the light that has entered through the light entry surface (10a) exits. The light-emitting diode unit (9) has light-emitting elements (26a and 27a) arranged linearly on a base member (28) with a prescribed interval therebetween, and sealing resin elements (26b and 27b) that seal respective light-emitting elements (26a and 27a). The light entry surface (10a) of the light guide plate (10) is shaped so as to engage with the sealing resin elements (26b and 27b).

Abstract: The embodiments of present disclosure disclose a prism sheet, a backlight module and a liquid crystal display device thereof. The prism sheet comprises a first sub-prism sheet and a second sub-prism sheet with faces being closely bonded with each other, the first sub-prism sheet having a plurality of protrusions on the surface being bonded with the second sub-prism sheet, and the second sub-prism sheet having recesses on the surface being bonded with the first sub-prism sheet corresponding to the protrusions, wherein the first sub-prism sheet and the second sub-prism sheet are made of materials having different refractive indexes.

Abstract: Electronic devices may include displays having backlight structures that include optical films. The optical films may help guide light from the backlight structures to display layers that generate display images using the light. The optical films may be attached together at one or more locations. The optical films may be attached to a structural member of the backlight structures. The structural member may be formed along each edge of the optical films and prevent the optical films from sliding within the display. Each optical film may be designed to expand to a common lateral size when the display is operated at a display operating temperature. The optical films may each include an elongated opening such as a slot through which a pin can be placed to partially constrain the movement of the optical films while allowing the optical films to expand or contract under changing thermal conditions in the display.

Abstract: Discussed are a liquid crystal display device and an assembly method thereof, which are capable of reducing, as much as possible, the width of a bezel defining an outer appearance of the liquid crystal display device through variation of an assembly structure of a liquid crystal panel and a backlight unit and variation in the size of the backlight unit. The liquid crystal display device can include a backlight unit including a plurality of light sources, a light source holder, and a light guide plate, and a liquid crystal panel arranged at a front side of the backlight unit and fixed to the backlight unit by an adhesive material.

Abstract: The present invention enables a liquid crystal display device using LEDs as a light source to reduce uneven brightness, increase efficiency of heat discharged from the LEDs, and provide area brightness control. The liquid crystal display device includes a liquid crystal display panel and a backlight. The backlight includes a light guide panel and a plurality of LEDs arranged on a line. The light guide panel includes a concave portion extending in a longitudinal direction of the light guide panel. A large number of LEDs are placed in the concave portion of the light guide panel. The plurality of LEDs arranged on a line emit light alternately in opposite directions. This configuration allows for uniform brightness distribution without forming a large number of concave portions in the light guide panel. Further, this configuration also allows for area brightness control by controlling a large number of LEDs by group.

Abstract: An LCD device adapted to prevent a malfunction due to static electricity is disclosed. The LCD device includes: a liquid crystal display panel; a panel guider configured to support edges of the liquid crystal display panel; a bottom cover combined with the panel guider; and at least one conductive tape attached to the liquid crystal display panel and the bottom cover, and configured to include: a plurality of slit trains formed in a pattern, that positions of slits in one of the slit trains are shifted from those in adjacent slit trains along a first direction.

Abstract: A display device includes a display panel and a backlight unit. The display panel is configured to display an image. The backlight unit is configured to provide light to the display panel. The display panel includes an array substrate including a plurality of pixel areas, an opposite substrate facing the array substrate, a liquid crystal layer disposed between the array substrate and the opposite substrate, and a wavelength-selective transflective member disposed on the array substrate or the opposite substrate.

Abstract: A display device is provided, comprising a display panel and a polymer dispersed liquid crystal panel overlapped in order, and an ambient light source system disposed at a side of the polymer dispersed liquid crystal panel opposite to the display panel. The display device is simplified in structure and driving circuit thereof while avoiding impact on heat-resistance performance of the PDLC panel resulted from over temperature of the light source at side of the light guide plate.

Abstract: Provided is a backlight unit that is capable of suppressing an uneven brightness. The backlight unit (2) includes a lower lens sheet (91) and an upper lens sheet (92) that are disposed in an inside area of a frame portion of a frame (4) and that are laminated in this order, and a rim tape (10) attached to the frame portion of the frame (4). The upper lens sheet (92) is fixed in position by a wide portion (10a) of the rim tape (10) being affixed to the upper surface of an end (92b) of the upper lens sheet (92), while the lower lens sheet (91) is held without being affixed to the wide portion (10a) of the rim tape (10).

Abstract: According to one embodiment, a lighting device includes a radiation surface, at least one light source provided to face the radiation surface, and an optical control member provided between the radiation surface and the light source and includes optical characteristics of transmission, diffraction, diffusion, and reflection, which vary for regions in the optical control member, a distribution of each of the optical characteristics being determined by positions relative to the at least one light source. The optical control member is formed in a sheet shape which is controlled by at least one of a reflective film having a reflection factor distribution, and a reflective film having a numerical aperture distribution, and lenses.

Abstract: The present invention is a display assembly in which a backlight module generates light beams via a light source. The light source provides the light beams to a light guide of the backlight module. The light guide then provides the light beams to a display panel of the display assembly for illuminating the display panel. One or more optical elements are implemented between the light source and an insertion edge of the light guide for promoting improved light insertion efficiency for the display assembly. Further, the optical element(s) may promote improvements in color quality, luminance and/or uniformity of graphics or graphical depictions displayed by the display assembly.

Abstract: Provided is a liquid crystal display device in which uneven brightness in a side-light type backlight unit is reduced, the uneven brightness being generated through reflection of light from a light source at an interface of an engaging cutout portion for preventing a light guide plate from shifting. A light guide plate (60) includes a cutout portion (82) through which a light guide plate support pin (80) provided upright to a lower frame fitting is inserted, at a lower side adjacent to a left side at which a light bar (64) is arranged. Further, at the lower side, a cutout portion (84) having a shallower recess than that of the cutout portion (82) and positioned in front of the cutout portion (82) when viewed from the light bar (64) is provided.

Abstract: A display apparatus that includes a light amount adjustment section includes a lens provided corresponding to a light receiving region of a photo-sensor element. The light amount adjustment section varies the focus position of the lens with respect to the light receiving region of the photo-sensor element to adjust the amount of light to be introduced to the light receiving region.

Abstract: A backlight unit is provided that comprises a first layer, a plurality of light sources on the first layer, a reflection layer on the first layer, the reflection layer surrounding the plurality of light sources, a second layer on the reflection layer and the plurality of light sources, and a third layer on the second layer, the third layer comprising a plurality of light shielding patterns arranged to correspond to the light sources, respectively, and a light transmitting region surrounding the plurality of light shielding patterns, wherein the light transmitting region includes first regions adjacent to the light sources and second regions away from the light sources, and wherein the first regions are smaller in area than the second regions. A display apparatus comprising the backlight unit is provided as well.

Abstract: The present invention provides a light leakage prevention backlight unit comprising: a backplane for supporting the backlight unit; a heat dispassion bar disposed on the backplane and comprising a horizontal plate having an edge and a vertical plate extending from the edge of the horizontal plate and having an outer side and an inner side; a light bar disposed at the inner side of the vertical plate of the heat dispassion bar; a reflective plate, a light guide plate, and an optical film group sequentially disposed on the horizontal plate of the heat dispassion bar from bottom to top, wherein a light incident surface of the light guide plate is directly opposite to the light bar; an outer case disposed at the outer side of the heat dispassion bar and comprising multiple platforms, wherein the platforms are supported by the vertical plate of the heat dispassion bar, and some of the platforms are disposed above the outer peripheral of the optical film group; and a positioning piece disposed at an end portion of

Abstract: The purpose of the present invention is to provide a polarizing plate protective film and liquid crystal display device comprising same whereby the generation of egg-shaped blur in a liquid crystal display device (especially an IPS liquid crystal display device) can still be limited even under high-temperature/high-humidity conditions. For this polarizing plate protective film, if nx is the refractive index in the X-axis direction at which the birefringence in the film surface reaches a maximum and ny is the refractive index in the Y-axis direction orthogonal to the X-axis direction in the film surface, then the birefringence under stress (nx?ny) of the film as measured at a wavelength of 589 nm when any tensile stress 5-35 MPa is applied in the X-axis direction or Y-axis direction of the film under 50 DEG C, 80% RH conditions is 0.

Abstract: A backlight unit for a liquid crystal display device including a liquid crystal panel, includes: a light source including a light-emitting diode (“ED”) which generates and emits light; and a light converting layer between the light source and the liquid crystal panel, spaced apart from the light source, and converting the light from the light source into white light and emitting the white light toward the liquid crystal panel. The light converting layer includes: semiconductor nanocrystals, and a barrier material which restricts penetration of moisture or oxygen.

Abstract: The present invention relates to a light output device (10) comprising a plurality of light source units (18) arranged in a laminated glass structure. The light output device is characterized by a plurality of switchable liquid crystal-based (24) devices arranged to alter the beam shapes of light emitted by the light source units when in a beam shape altering mode. The present invention also relates to a method for controlling a light output device.

Abstract: The present invention discloses a backlight module which includes a waveguide and a spot light source. Wherein the waveguide includes an incident face and a refractive surface adjacent to the waveguide, the light beam emitted from the spot light source will be directed toward the refractive surface, and then the light beam enters the waveguide after the light beam is refracted by the refractive surface. The present invention also discloses a liquid crystal display device incorporated with the backlight module disclosed. The backlight module can readily improve the corner vignette and enhanced with more evenly distributed brightness across the waveguide. The liquid crystal display device incorporated with the module also enjoy the evenly distributed brightness.

Abstract: A liquid crystal display apparatus includes a liquid crystal layer, a light source, a first polarizing member, and a reflector. The first polarizing member includes a wire-grid polarizing part and a reflection part. The first polarizing member is disposed between the liquid crystal layer and the light source. The reflector is disposed below the light source. The reflector reflects light from the light source and light reflected from the reflection part.

Abstract: Provided is a liquid crystal display including: a lower display panel including a lower insulating substrate and a lower reflective layer; an upper display panel including an upper insulating substrate and an upper reflective layer; a liquid crystal layer positioned between the lower reflective layer of the lower display panel and the upper reflective layer of the upper display panel; and a backlight unit positioned on a lower portion of the lower display panel and including a light source, wherein a pair of field generating electrodes are formed in at least one display panel of the lower display panel and the upper display panel, wherein microcavities are formed in the lower reflective layer, the upper reflective layer, and the liquid crystal layer, and wherein a wavelength and luminance of light resonated and emitted in the microcavities are changed by an electric field generated by the field generating electrodes.

Abstract: A display apparatus includes a backlight assembly which provides a light and a display panel which receives the light provided from the backlight assembly to display an image. The backlight assembly includes a light source which generates the light, and a light guide plate. The light guide plate receives the light generated from the light source through an incident surface thereof as an incident light, and outputs the incident light through an exit surface thereof as an exit light. The light guide plate includes a first optical pattern and a second optical pattern. The first optical pattern is disposed corresponding to a first area of the exit surface and collects the incident light. The second optical pattern is disposed corresponding to a remaining second area of the exit surface excluding the first area, and collects the exit light.

Abstract: The present invention discloses a liquid crystal display module, a backlight module and a back plate thereof. The back plate has a back-plate mainbody disposed on a bottom of the backlight module, and two bent structures integrally and symmetrically arranged on two opposite sides of the back-plate mainbody for supporting an optical film assembly of the backlight module. The present invention is applied to a LCD module with a separate-type backlight module design for saving the used number of housing strips, simplifying the structure of the backlight module, and enhancing the stability thereof.

Abstract: A method of manufacturing a planar light source includes disposing a plurality of light emitting devices on a substrate and disposing an optical sheet to be separated from the light emission surface formed by the plurality of light emitting devices by an optical length l, the step of disposing the plurality of light emitting devices on the substrate including determining a degree of pitch S between two adjacent light emitting devices among the plurality of light emitting devices, and the step of determining the degree of pitch S including: calculating a degree of luminance of the light emitting device in the optical sheet, and determining a distance between one region in the optical sheet directly above the light emitting device, and another region in the optical sheet having a half of maximum luminance, to be S/2.

Abstract: The present invention discloses a backlight module and a liquid crystal display (LCD). A backlight module comprising an optical film, at least one light source, at least one reflecting housing and a reflecting surface. The reflecting surface and the optical film are symmetrically disposed with respect to the light source, and are disposed in identical side of the light source; the reflecting housing comprises a first reflecting layer and a second reflecting layer; the reflecting surface has a predetermined trajectory, and corresponds to the first reflecting layer and the light source. In the predetermined trajectory, the lights entering into the reflecting surface are reflected by the reflecting surface and enter into the optical film.

Abstract: The current invention relates to a sunlight readable full color active matrix liquid crystal display devices. By means of a novel Directional Light Guiding (DLG) film structure, both the internal backlight and the external sunlight can be used synergistically for lighting the display so as to deliver superior readability and color quality. A seamless transition between indoor and outdoor applications makes the vivid true color display an ideal solution to portable electronics.

Abstract: An illuminated display device with a base member with a plurality of cavities therein. Illumination devices illuminate the cavities and emit light through an opening of the cavities in a pattern, and a speaker can emit sounds in synchronization with the pattern. A panel with translucent portions can overly the base member and the cavities. An animated talking character can have an animated mouth cavity complex with multiple predetermined mouth lighting configurations simulative of human utterances. The cavities can be open, or optical waveguide material or positive members can be disposed therein. Reflective material can enhance internal reflectance and light emission.

Abstract: Provided are a backlight unit and a display device having the same. The backlight unit configured to emit light onto a display panel in which one screen is defined into a plurality of display areas includes a bottom frame having a bottom surface and a sidewall, a plurality of light emitting diodes (LEDs) defining a plurality of light emitting areas corresponding to the display areas of the display panel, and an integrated light guide plate covering the plurality of LEDs, the integrated light guide plate being disposed on the plurality of light emitting areas corresponding to one screen. The light guide plate has a plurality of grooves for receiving at least one LED in an under surface thereof.

Abstract: Utilization of quantum dots in displays and the location of the quantum dot sheet within the stackup of the backlight can lead to issues such as non-uniform light mixing, non-uniform brightness, and off-axis changes in color. The mismatch between the isotropic nature of light emitted from the quantum dots and the light emitted directly from the light source can be alleviated by utilization of diffusers and prism sheets. The diffusers and prism sheets can be further utilized to change the angle of light such that it is directed upwards towards the top of the display for improved uniformity in brightness and enhanced performance. Placement of the diffuser sheets, prism sheets, and changes in the design of the components, such as the light guide path, can alleviate the issues by properly mixing the colors together in order to achieve a uniform distribution of colors in the display.

Abstract: The present invention discloses a backlight module and a liquid crystal display (LCD). The backlight module includes a backplane, a light guide plate, a heat dissipation element and a connector. The light guide plate is disposed on the side of the backplane. The heat dissipation element includes a horizontal part and a vertical part interconnected to each other. The horizontal part is disposed on the other side of the backplane away from the light guide plate, and the vertical part is disposed next to light incident surface of the light guide plate. The light source is disposed on the side of the vertical part close to light incident surface. The connector connects the heat dissipation element to the backplane and allows the heat dissipation element to move relatively to the backplane in the gap direction between the light guide plate and the light source.

Abstract: A light generating device which may be used as a backlight unit and a display device including the light generating device are discussed. According to an embodiment, the light generating device can include a base layer; light source devices disposed on the base layer and configured to emit light, the light source devices being spaced apart from each other, at least one of the light source devices including a light emitting diode for generating the light; and a light shielding layer covering the light source devices and configured to control an amount of the light being transmitted through the light shielding layer, wherein the light shielding layer includes slits disposed spaced apart from each other.

Abstract: A backlight includes a case having plural apertures in a main face thereof and a light source disposed in the case. A total area of the plural apertures is not less than 8% and not more than 15% of an area of the main face.

Abstract: A backlight unit having improved luminance and reduced profile, and a liquid crystal display including the same are disclosed. In one embodiment, the backlight unit includes: i) a light source, ii) a light guiding plate including an incoming surface on which light generated from the light source is incident, an upper surface substantially perpendicularly extended with respect to the incoming surface, and a bottom surface arranged facing the upper surface and iii) an optical sheet formed on the light guiding plate. The upper surface of the light guiding plate includes a guiding surface, an incoming surface, and an emission surface sequentially arranged close to the incoming surface of the light guiding plate, and the optical sheet may be formed to cover the inclined surface and the guiding surface.

Abstract: A liquid crystal display device is provided. The liquid crystal display device includes a light-shielding member to prevent light irradiated upward from a light-emitting surface of a plurality of light-emitting diodes from being incident on a lower edge of an incident surface of a light-guide portion. As a result, a bezel surrounding a liquid crystal display panel may be made thinner, and a bright line defect, hot spot, may be prevented.

Abstract: An objective of the present invention is to enable making a liquid crystal display device thin, and to enable regional control of window brightness with power conservation. A backlight of a liquid crystal display device comprises a plate-shaped light guiding plate (20). Recesses (21) are formed on the light guiding plate (20), and LEDs (30) are housed in the recesses (21). The LEDs (30) further comprise light emitting faces (301) and rear faces. The rear faces of the LEDs (30) are brought into contact with the interior walls of the recesses (21) of the light guiding plate, and light that leaks from the rear faces of the LEDs (30) is proactively used. A resin (25) for optical coupling is positioned between the LEDs (30) and the interior faces of the recesses (21). Using the light from the rear faces of the LEDs (30) allows reducing the number of LEDs that need to be lit, allowing obtaining a liquid crystal display device with minimized power consumption.

Abstract: A liquid crystal display (LCD) is provided. The LCD includes at least one light source which provides light, a display panel which includes pixels reflecting the light from the light source, and at least one light guide plate (LGP) which is formed substantially parallel to a surface of the display panel and is separated from the display panel, wherein a predetermined space is defined between the LGP and the display panel, and the LGP guides the light emitted from the light source to the pixels and allows the light reflected by the pixels to pass through the LGP.

Abstract: An optical substrate having a structured prismatic surface and an opposing structured lenticular surface. The structured lenticular surface includes shallow-curved lens structures. Adjacent shallow-curved lens structure may be continuous or contiguous, or separated by a constant or variable spacing. The lens structure may have a longitudinal structure with a uniform or varying cross section. The lenticular lenses may have a laterally meandering structure. Sections of adjacent straight or meandering lenticular lenses may intersect or partially or completely overlap each other. The lenticular lenses may be in the form of discontinuous lenticular segments. The lenticular segments may have regular, symmetrical shapes, or irregular, asymmetrical shapes, which may be intersecting or overlapping, and may be textured. The lens structure may be provided with isolated ripples, in the form of a single knot, or a series of knots.

Abstract: Provided is a back-light unit. The back-light unit includes: a reflective layer; a light transmitting plate including a plurality of light emitting diodes; and an optical member disposed on the light transmitting plate and separated from the light transmitting plate with an air layer therebetween, in which light generated from the light emitting diode is reflected to the reflective layer and then passes through the light transmitting plate to reach the optical member.

Abstract: A display unit for a motor vehicle, having a display area with a back-lit liquid crystal display device bounded by a border area is provided. The display unit includes a light source, and behind the display area a liquid crystal cell, a first polarizer and a second polarizer, the light source being configured to provide back-light illumination to the cell and the polarizers forming a pair of polarizers on opposite sides of the cell such that, in use, the first polarizer polarizes the illumination and the second polarizer either passes or blocks this illumination when the polarisation of the illumination is rotated by the cell. A first cover sheet extends over said cell, and a second cover sheet extends over the first cover sheet.

Abstract: The backlight module comprises a backplane and a light guide plate arranged in the backplane. The backlight module also comprises a limiting member for limiting the light guide plate. The limiting member comprises a horizontal limiting structure. The horizontal limiting structure abuts against an edge of the light guide plate and a side wall of the backplane. A limiting member is arranged between the edge of the light guide plate and the side wall of the backplane. One side of the limiting member abuts against the light guide plate, and the other side of the limiting member abuts against the side wall of the backplane. The limiting member is used for filling in a gap from the side wall of the backplane to the edge of the light guide plate. Thus, the horizontal limiting of the light guide plate by directly using the limiting member is achieved.

Abstract: A transflective liquid crystal display includes a liquid crystal panel including a first substrate, a second substrate, a liquid crystal layer, the first and second substrates arranged to face each other and the liquid crystal layer between the first and second substrates, a reflection polarizer and an absorption polarizer at opposing outer sides of the liquid crystal panel, and a backlight unit at an outer side of the liquid crystal panel and supplying light to the inside of the liquid crystal panel. A reflective axis of the reflection polarizer is parallel with a transmissive axis of the absorption polarizer, the transmissive axis of the reflection polarizer perpendicularly crosses the transmissive axis of the absorption polarize, and the liquid crystal layer includes liquid crystal molecules and a dichroic dye.

Abstract: A liquid crystal shutter includes a plurality of liquid crystal layers arranged in a light-incident direction; and a plurality of polarizers attached to each of the plurality of liquid crystal layers, polarization axes of 2 adjacent polarizers that have a liquid crystal layer therebetween being crossed at an angle of 90°, the accumulated value of degrees of polarization of polarizers that have polarization axes in a first direction being identical to that of degrees of polarizations of polarizers that have polarization axes in a second direction that crosses the first direction at an angle of 90°.

Abstract: To sophisticate a portable electronic appliance without hindering reduction of the weight and the size, more specifically, to sophisticate a liquid crystal display apparatus installed in a portable electronic appliance without hindering the mechanical strength, a liquid crystal display apparatus includes a first plastic substrate, a light-emitting device which is disposed over the first plastic substrate, resin which covers the light-emitting device, an insulating film which is in contact with the resin, a semiconductor device which is in contact with the insulating film, a liquid crystal cell which is electrically connected to the semiconductor device, and a second plastic substrate, wherein the semiconductor device and the liquid crystal cell are disposed between the first plastic substrate and the second plastic substrate.

Abstract: The liquid crystal display device may include a first electrode; a second electrode facing the first electrode and forming a vertical electrical field together with the first electrode; a blue phase liquid crystal layer provided between the first electrode and the second electrode; and a first prism sheet provided to face the second electrode with the first electrode between the second electrode and the first prism sheet. The first prism sheet changes a path of incident light so that the incident light from the outside obliquely enters the blue phase liquid crystal layer with respect to the vertical electrical field.

Abstract: An apparatus for providing a photoluminescent light source is disclosed. In one embodiment, the apparatus comprises a light source that emanates light of a particular spectrum, a camera, and a selective mirror placed between the light source and camera. The selective mirror transmits light of a spectrum detected by the camera and reflects light of a spectrum generated by the light source. The light source is transparent to light incident on its face.