1382results about How to "Improve brightness uniformity" patented technology

An optical system for a head-worn computer includes a light source positioned within the head-worn computer and adapted to project polarized illuminating light towards a partially reflective partially transmissive surface such that the illuminating light reflects through a field lens and towards a reflective display. The illuminating light reflects off a surface of the reflective display, forming image light. The image light is then transmitted through the field lens and then through the partially reflective partially transmissive surface to a lower display optical system adapted to present the image light to an eye of a user wearing the head-worn computer.

The invention discloses an alternating-current pixel driving circuit and method for an active organic light-emitting diode (OLED) display. The driving circuit comprises a driving transistor, a switch transistor, a storage capacitor and an OLED, wherein the drain of the first transistor is connected with a data wire; the grid of the first transistor is connected with a first scanning control wire; the source of the first transistor is connected with the end A of the storage capacitor; the drain of a second transistor is connected with the source of a third transistor; the grid of the second transistor is connected with the end A of the storage capacitor and the source of the first transistor; the source of the second transistor is connected with the drain of a four transistor and the end B of the storage capacitor, and is connected with the ground through the OLED; the drain of the third transistor is connected with a power wire; the grid of the third transistor is connected with a light-emitting control wire; the grid of the fourth transistor is connected with a second scanning control wire; and the source of the fourth transistor is connected with a reference potential. According to the driving circuit and method, the OLED works in an alternating-current driving mode, so that the characteristics of the OLED are recovered from degeneration state, the service life of the OLED is prolonged effectively, the threshold voltage drift of a thin film transistor and the degeneration of OLED cut-in voltage can be compensated effectively, and the uniformity of a display picture is enhanced.

A spread illuminating apparatus is provided where: a light introducing prism mechanism is formed at a light entrance surface of a light guide plate wherein the prism mechanism includes a plurality of prism pieces extending in the thickness direction of the light guide plate and including first and second light incidence faces which have respective different inclination angles relative to the light entrance surface such that the first and second light incidence face are inclined relative to the light incidence surface at an angle ranging from 0 degree to 30 degrees and at an angle ranging from 45 degrees to 90 degrees; a light emitting pattern is formed at the bottom surface of the light guide plate such that prisms are continuously disposed in a step-like manner in the direction perpendicular to the light entrance surface; and a light diffusing pattern is formed at the top surface of the light guide plate such that arc prisms are disposed in the direction parallel to the light entrance surface.

A planar light source system having an LED (1) serving as a primary light source of substantially point-shaped light source, a light guide (2) having a light incident face on which light emitted from the LED (1) is incident and a light emission face (4) from which light guided through the light guide (2) is emitted, a light deflecting device (3) for controlling the direction of the emission light from the light guide (2), and a reflection sheet (6). LED (1) is disposed at a corner portion of the light guide (2), and many elongated prisms (5) are arranged substantially arcuately in parallel to each other on the light incident surface (14) of the light deflecting device (3) so as to surround LED (1).

An enhanced light fixture containing a volumetric diffuser to control the spatial luminance uniformity and angular spread of light from the light fixture is disclosed. The volumetric diffuser provides increased spatial luminance uniformity and efficient control over the illuminance such that power reductions, reduced cost or reduced size may be achieved. The volumetric diffuser contains one or more regions of volumetric light scattering particles. The spread of illumination of light from a light emitting source can be efficiently controlled by using a thin, low cost, volumetric, diffuser to direct the light in the desired direction. This allows the reduction in number of light sources, a reduction in power requirements, or a more tailored illumination. When the volumetric diffuser is used in combination with a waveguide to extract light, the light is efficiently coupled out of the waveguide in a thin, planar surface. This transmissive diffuser can be coupled to a reflecting element such that the resulting combination is a light reflecting element with a desired light scattering profile.

Backlight with which the uniformity of brightness within a display area of a concavely curved liquid crystal display device is improved while fulfilling the demand for slimmer liquid-crystal display devices, as well as curved liquid-crystal display device including such a backlight. The shape of a frame, an optical sheet, and a scattering plate constituting the backlight unit is the same concavely curved shape as that of the concavely curved panel; and the liquid-crystal panel, the optical sheet, and cold-cathode luminescent lamps are arranged such that the concavely curved panel, the surface of a frame constituting the backlight unit that faces the concavely curved panel, an optical sheet surface, and a surface including the tube center axes of a plurality of cold-cathode luminescent lamps are parallel to each other.

To provide a liquid crystal display device having excellent uniformity in the brightness so that the performance of displays of liquid crystal can be increased.

A liquid crystal display device is provided with: a support member: a heat releasing member provided on this support member; a light guiding plate 121 provided on a rear surface of a liquid crystal panel; and a light source module 124 which is thermally secured to the heat releasing member so as to face an entrance surface 121a formed on one or two sides in the direction of the length of the light guiding plate 121 and has a light source for emitting a light beam toward the entrance surface 121a, wherein the light source is covered with a lens 124c in the light source module 124, and the distance D between the lens 124c and the entrance surface 121a when the light source module 124 is not driven is set within a certain range.

a pixel circuit including a light emitting device; a driving transistor to receive first power and supply current corresponding to voltage applied to a gate electrode thereof to the light emitting device; a first switching device to supply a data signal in response to a first scan signal; a second switching device to supply second power to the gate electrode of the driving transistor in response to the first scan signal; a capacitor to store voltage corresponding to the data signal and the second power according to operations of the first and second switching devices; a third switching device to apply voltage corresponding to the voltage stored in the capacitor to the gate electrode of the driving transistor in response to a second scan signal; and a fourth switching device to transmit the first power to the driving transistor in response to a third scan signal.

A lighting system, a reflector, light sources and a light control member are sequentially disposed from a light incident side to a light outgoing side. Preferably used for large displays requiring high uniformity, this invention eliminates lamp image and removes the necessity to do light source repositioning, while enabling luminance in the exit plane to achieve excellent luminosity and uniformity. This invention achieves total transmittance of more than 50% when light is incident on the normal direction of the incident plane at a predetermined angle α and achieves 1.05-3 times more total transmittance than when the light is normally incident. This is achieved by using a light control member such as the light diffusion plate described herein, which is conformed to obtain required luminosity and uniformity by controlling the ratio between total transmittance in the positions of greater transmittance and the total transmittance in the positions of lesser transmittance.

A light guide plate that is divided into an effective section capable of providing uniform surface illumination and a transitional section between the effective section and the point light source includes a light-receiving surface, a light-emitting surface, a light-reflecting surface, and a plurality of light-diffusing structures. The light-diffusing structures are spread on the transitional section, and each light-diffusing structure is in the shape of a part elliptic cylinder having a long axis and a short axis and the front surface of the light-diffusing structure facing the point light source is a part elliptic cylindrical surface.

Light color beams respectively from LEDs formed on an LED array substrate are allowed to enter one edge of second light guide plates for color mixing, which is arranged to either side of the LEDs. In each of the second light guide plates, color mixing of the respective color light beams occurs with increasing distance from this one edge, and thereby white light is obtained. This white light is guided out through the other edge of the second guide light plate, is reflected by a second reflection plate, and then is allowed to enter either of two opposite edges of a first light guide plate. The white light having entered the first light guide plate is radiated out from a front surface thereof.

A light emitting display having a pixel circuit for compensating driving voltage variation between pixels due to voltage drop in the voltage supply line. The light emitting display includes pixels, data lines extending in a first direction, through which a data signal is supplied to the pixels, scan lines extending in a second direction crossing the first direction, through which a selection signal is supplied to the pixels, a first power source line supplying driving voltage to the pixels, and a second power source line along the first direction supplying a compensating voltage to the pixels. The compensating voltage compensates for the drop of driving voltage across pixels that can cause non-uniformity in brightness of the display.

A backlight module of an LCD device includes a plurality of fillisters formed in a reflection sheet and each of the fillisters having a reflection surface and a symmetrical axis. A plurality of point light source generators set in the fillisters, in which lights generated by the point light source generators are reflected by the reflection surfaces of the fillisters and the reflection sheet, and a profile of the point light source generators determines a shape of the fillisters. At least one diffuser plate installed on the reflection sheet for scattering the lights generated by the point light source generators and reflected by the reflection surfaces of the fillisters and the reflection sheet, in which an air space is formed between the diffuser plate and the reflection sheet.

A head-worn see-through display includes a display panel adapted to generate image content light, a combiner adapted to reflect the image content light towards an eye of a user, wherein the combiner transmits scene light from a surrounding environment to the eye of the user, and an image expansion optic intermediate the display panel and the combiner. The image expansion optic includes a flat partially reflective and partially reflective surface (the “flat surface”), a curved partially reflective and partially reflective surface (the “curved surface”), and the flat surface adapted to reflect the image content light towards the curved surface and the curved surface adapted to reflect the image light back towards the flat surface, wherein the image light transmits through the flat surface towards the combiner.