4463 results about "Light modulation" patented technology

The video display apparatus has a light modulation device for forming a picture in accordance with a video signal and a lighting unit for irradiating, on the light modulation device, illumination light necessary to cause it to display the picture. In the apparatus, the lighting unit irradiates the illumination light in sequence of individual plural illumination light source partitive areas, a luminance distribution calculating unit calculates luminance distributions of video signals corresponding to the plural partitive areas to determine illumination light luminance levels of the individual partitive areas, an illumination controller controls rays of the illumination light of individual areas of the lighting unit on the basis of determination by the luminance distribution calculating unit, and a video corrector corrects the video signal inputted to the light modulation device on the basis of the determination by the luminance distribution calculating unit.

In a display panel, a dummy pulse of a predetermined voltage signal is superimposed on a data signal and the dummy pulse has an amplitude much larger than the amplitude of the data signal, and thus a signal waveform applied to a light modulation layer such as LC layer is changed to a high frequency wave. The applying position of the dummy pulse is varied according to each color of R, G and B, or varied according to frame or field. By performing a MLS drive with the dummy pulse superimposed on the data signal, the amplitude difference between the selection signal and the data signal can be reduced. Thus, a common driver IC and a segment driver IC can be formed as one semiconductor chip to be placed on one side, constructing a three side free type.

Optical coherence tomography with 3D coherence scanning is disclosed, using at least three fibers (201, 202, 203) for object illumination and collection of backscattered light. Fiber tips (1, 2, 3) are located in a fiber tip plane (71) normal to the optical axis (72). Light beams emerging from the fibers overlap at an object (122) plane, a subset of intersections of the beams with the plane defining field of view (266) of the optical coherence tomography apparatus. Interference of light emitted and collected by the fibers creates a 3D fringe pattern. The 3D fringe pattern is scanned dynamically over the object by phase shift delays (102, 104) controlled remotely, near ends of the fibers opposite the tips of the fibers, and combined with light modulation. The dynamic fringe pattern is backscattered by the object, transmitted to a light processing system (108) such as a photo detector, and produces an AC signal on the output of the light processing system (108). Phase demodulation of the AC signal at selected frequencies and signal processing produce a measurement of a 3D profile of the object.

A thin film electroluminescent (TFEL) phototherapy device based on high field electroluminescence (HFEL) or from organic light emitting devices (OLED), consistent with certain embodiments of the present invention has a battery and a charging circuit coupled to the battery, so that when connected to a source of current acts to charge the battery. A TFEL panel produces light when voltage from the power source (battery or AC source) is applied. A processor such as a microprocessor is used to control the application of voltage from the power source to the TFEL panel under control of a control program. A housing is used to contain the battery, the charging circuit and the processor and carry the TFEL panel on an outer surface thereof. In one embodiment, the housing incorporates a removable cover that uncovers a household electrical plug useful for supplying charging current to the charger. In use, a method of carrying out phototherapy, consistent with certain embodiments of the invention involves diagnosing a condition of an affected area of tissue that can be treated with phototherapy. A treatment protocol is determined including, for example, a treatment light intensity, a treatment time, a light modulation characteristic and a treatment light wavelength suitable for treating the condition. The affected area is then irradiated with light from the TFEL panel in accord with the treatment protocol.

Techniques for directly converting an electrical signal into an optical signal by using a whispering gallery mode optical resonator formed of a dielectric material that allows for direct modulation of optical absorption by the electrical signal.

To optionally forming a multilevel light intensity distribution on an illumination pupil plane, the illumination apparatus implements Köhler illumination on an illumination target surface, using as a light source the light intensity distribution formed on the illumination pupil plane on the basis of light from a light source. The illumination apparatus has a spatial light modulator, a condensing optical system, and a control unit. The spatial light modulator has a plurality of reflecting surfaces which are two-dimensionally arranged and postures of which can be controlled independently of each other. The condensing optical system condenses light from the reflecting surfaces to form a predetermined light intensity distribution on the illumination pupil plane. The control unit controls the number of reflecting surfaces contributing to arriving light, for each of points on the illumination pupil plane forming the light intensity distribution, according to a light intensity distribution to be formed on the illumination pupil plane.

There is provided with an image display method including: creating a histogram indicating frequencies of pixels included in level-ranges associated with representative gray-scale levels; calculating differences between first brightnesses each predetermined for the each representative gray-scale level and second brightnesses each preliminarily obtained for the each representative gray-scale level displayed on an image display with each of a plurality of light-source levels of light-source luminance, accumulating, for each of the representative gray-scale levels, products of the differences by the frequency, selecting a selected light-source level having the smallest accumulated sum or the smaller accumulated sum than a threshold value; providing signals of one frame of an input video image to a light modulation device that displays an image by modulating a transmittance or a reflectance of light from a light source, and controlling so that the light source emits light in luminance corresponding to the selected light-source level.

An optical communications network includes a terminal which can simultaneously receive and modulate an optical signal. The terminal includes an optical modulator which is controlled by varying the bias voltage applied to it.

A projector has: light source (1R, 1G, 1B); a light modulation unit (6) that modulates a light emitted from the light source based on image signals; a display control unit (41) that outputs the image signals including main cyclic image signals to the light modulation unit, and controls the display thereof; a projection unit (7) that projects the image based on the light modulated by the light modulation unit; and an imaging unit (40) that captures an image to be displayed based on the light projected from the projection unit, and the display control unit inserts a correction image signal for projecting a correction image, which is visually recognized as a uniform white or gray screen when time integration is performed, between the cyclic main image signals.

A MEMS optical display system includes an illumination source for providing illumination light, a collimating lens for receiving the illumination light and forming from it collimated illumination light, and a converging microlens array having an array of lenslets that converge the collimated illumination light. The converging microlens array directs the illumination light to a microelectrical mechanical system (MEMS) optical modulator. The MEMS optical modulator includes, for example, a planar substrate through which multiple pixel apertures extend and multiple MEMS actuators that support and selectively position MEMS shutters over the apertures. A MEMS actuator and MEMS shutter, together with a corresponding aperture, correspond to pixel. The light from the converging microlens array is focused through the apertures and is selectively modulated according to the positioning of the MEMS shutters by the MEMS actuators, thereby to impart image information on the illumination light. The light is then passed to a diffused transmissive display screen by a projection microlens array.

A privacy display comprises a spatial light modulator and a passive retarder arranged between first and second polarisers arranged in series with the spatial light modulator. On-axis light from the spatial light modulator is directed without loss, and off-axis light has reduced luminance. The visibility of the display to off-axis snoopers is reduced by means of luminance reduction over a wide polar field of view. Off-axis visibility of the display in an automotive vehicle can be reduced.

There is provided a circuit for driving a current mode light modulating device. The circuit includes (a) a capacitor for storing a data voltage, (b) a field effect transistor (FET) controlled by a signal on a scan line, for coupling the data voltage from a signal line to the capacitor, and (c) a current source, controlled by the stored data voltage, for driving the device with current provided from a power line. The power line is in a plane that is geometrically parallel to a plane within which the scan line is located.

An image display apparatus includes an image display unit having a light source and a light modulating unit; a histogram generating unit; a function generating unit; a first brightness calculating unit; a second brightness calculating unit; a first difference calculating unit; a first multiplying unit; a first summation calculating unit; a first brightness gradient calculating unit; a second brightness gradient calculating unit; a second difference calculating unit; a second multiplying unit; a second summation calculating unit; a weighted linear sum calculating unit; a determination unit; a control parameter selecting unit; and a control unit.

Methods and apparatus for enhancing the performance of a reflective liquid crystal display system. The high-contrast color splitting prism system utilizes a "double-passed" prism assembly. Polarized light enters the prism assembly, is color-split and emitted as separate colors to spatial light modulators which reflect each color in accordance with a desired image. The reflective light is passed, once again, through the prism assembly where the separate colors converge and propagate to a projection lens for display of the image on a screen. A waveplate retarder is positioned between the liquid crystal display and the polarizing element. The waveplate retarder is tilted with respect to the optical axis to eliminate the deleterious effects of the Fresnel reflections at the interfaces of the waveplate retarder.

A privacy display comprises a polarised output spatial light modulator, reflective polariser, switchable liquid crystal retarder and polariser. In a privacy mode of operation, on-axis light from the spatial light modulator is directed without loss, whereas off-axis light has reduced luminance. Further, display reflectivity is reduced for on-axis reflections of ambient light, while reflectivity is increased for off-axis light. The visibility of the display to off-axis snoopers is reduced by means of luminance reduction and increased frontal reflectivity to ambient light. In a wide angle mode of operation, the liquid crystal retardance is adjusted so that off-axis luminance and reflectivity are unmodified.

A color projection display in which at least one color channel includes: a light source assembly including a multiplicity of pulse modulated light sources providing an aggregate light beam; a light modulation control subsystem; illumination optics to direct the aggregate light beam to an image modulation plane; and a spatial light modulator in the image modulation plane. The light modulation control subsystem senses an aggregate light intensity signal for the aggregate light beam and controls the pulse modulation parameters for the multiplicity of pulse-modulated light sources responsive to the sensed aggregate light intensity signal to reduce light intensity fluctuations in the aggregate light beam within the imaging time interval.

An optical device includes: a light modulation element that modulates a luminous flux emitted from a light source; a casing that houses the light modulation element; a holding member that holds the light modulation element and exposes a part thereof to outside; a refrigerant housed in a housing space surrounded by the casing, the holding member and the light modulation element; and a convection start unit that is provided in the casing and causes convection of refrigerant.

An ambient light sensor 10 and a backlight sensor 9 are located on the liquid crystal panel 6 adjacently to each other, for correcting a variation of an output characteristic of the ambient light sensor 10. This location keeps the manufacturing variation of each liquid crystal panel 6 even in these two light sensors 9 and 10. A degree of variation of an output of the backlight sensor 9 for sensing a ray of backlight from a backlight module relative to a predetermined reference value is detected. Based on the detected result, the output of the ambient light sensor 10 is corrected. This operation makes it possible to improve sensing accuracy of the ambient light sensor 10 and keep the light modulation even in each liquid crystal panel provided with the ambient light sensor 10.

A transmission liquid crystal display device using a backlight device for supplying display light emitted from a large number of light emission diodes to a transmission display panel. The transmission liquid crystal display device has an optical sheet block (10) between a liquid crystal panel (5) and a light source unit (7) having a large number of LEDs (12) and has a light diffusion plate (15), which has light transmission properties and is made of resin, for controlling the incidence of display light emitted from each of the LEDs (12). On the light diffusion plate (15) are formed vertically long light modulation patterns (18) by using light reflective ink. Each pattern (18) faces each LED (12) and has a size equal to the size of each LED (12) including its external shape. The light modulation patterns (18) uniformize the light emitted from the LEDs (12) and realize an image display of high brightness where color irregularity and horizontal stripes are suppressed.

A digital photographic camera with brightness compensation and a compensation method thereof are applied for the brightness compensation of the digital photographic camera when shooting under different environments so as to maintain a frame rate. The camera includes a light measuring unit, a sensor, a light source generator, a light modulation unit, an operational unit, and a storage unit. The light measuring unit is used for sensing the environment brightness of the camera. The light modulation unit is coupled to the light source generator and used for controlling luminance of the light source generator. The operational unit is coupled to the light measuring unit and the light source generator, and executes a brightness calibration process for calibrating a brightness sensing reference value of the light measuring unit and a brightness compensation process for adjusting the luminance of the light source generator according to the environment brightness of the camera.

A method and system for exposing a light sensitive material using device for forming a row of spots of light onto the light sensitive material located on a focal plane, device for modulating each of the spots according to imaging data so that at any point of time, the row of spots forms a data pattern according to the imaging data, device for generating relative motion between the imaging mechanism and the light sensitive material on the focal plane, the direction of motion substantially parallel to the direction of the row of spots on the light sensitive material; and data synchronizing device for shifting the imaging data into the modulating device at a rate determined by the speed of relative motion to maintain the image of any data pattern substantially stationary on the light sensitive material.

An optical MEM device is fabricated with a patterned device layer formed on a silicon wafer. Preferably, the patterned device layer is patterned with plurality of ribbons and / or access trenches. The central portion of the ribbon is released from the silicon wafer using a selective etch process, wherein a cavity is formed under the central portion of the ribbon, while opposing ribbon ends remain attached to the wafer. The selective etching process preferably utilizes an enchant comprising xenon difluoride. In accordance with further embodiments, the silicon wafer is doped, patterned or otherwise modified to enhance the selectivity of the etching process.

In an embodiment of the invention, a microcavity OLED device that minimizes or eliminates color change at different viewing angles is fabricated. The OLED device can be, for example, an OLED display or an OLED light source used for area illumination. This OLED device includes a multi-layer mirror on a substrate, and each of the layers are comprised of a non-absorbing material. The OLED device also includes a first electrode on the multi-layered first mirror, and the first electrode is substantially transparent. An emissive layer is on the first electrode. A second electrode is on the emissive layer, and the second electrode is substantially reflective and functions as a mirror. The multi-layer mirror and the second electrode form a microcavity. On a front surface of the substrate is a light modulation thin film. The light modulation thin film can be any one of: a cut-off color filter, a band-pass color filter, a brightness enhancing film, a microstructure that attenuates an emission spectrum at an angle at which there is a perceived color change, or a microstructure that redistributes wavelengths so the outputted emission spectrums have the same perceived color.

An optical transmission apparatus for high-speed optical signal transmission is provided. The optical transmission apparatus includes an optical modulator which includes first and second modulators of a Mach-Zehnder (MZ) interferometer type which are connected in parallel, and an output stabilizer which controls biases for the first modulator, the second modulator and the optical modulator and stabilizes a final output optical signal of the optical modulator. The optical transmission apparatus can perform a stable optical signal output.