International Business Machines Corporation

Snap Inc.

Compound Photonics Limited

Toppoly Optoelectronics Corporation

Kyocera Corporation

Chi Mei Optoelectronics Corporation

James Lawrence Sanford

Howard V Goetz

Frank Robert Libsch

Kei-Hsiung Yang

Stephen John Hart

Robert Lee Melcher

Jonathan A Sachs

Evan G Colgan

Minhua Lu

Eugene S Schlig

Nicholas William Melena

Rock Edward Kent

Russell Alan Budd

Chandrasekhar Narayan

Stewart S Taylor

Derek Brian Dove

Steven Howard Linn

Punit P Chiniwalla

Teruhiro Nakasogi

James B Lillie

Jeffery A Engelman

Nicholas W Melena

Edward Rock Kent

Systems and methods for improving operating characteristics of displays such as liquid crystal on silicon displays.

Systems and methods for improving operating characteristics of displays

Systems and methods for a digital pixel circuit for liquid crystal displays are provided. The design includes a dual-voltage pixel design, a two-transistor level-shift circuit design, self-adjusting transistor bias circuitry; and an optional on-chip test-array to determine die-specific design-center values for critical transistor leakage and threshold parameters. Level shift design simplicity, small pixel pitch, and applicability for small display applications such as microdisplays, are among the various benefits and advantages obtained.

Dual-voltage pixel circuitry for liquid crystal display

Systems and method for improving operating characteristics of displays

A technique for modulating light by an optically addressed, electric charge accumulating spatial light modulator achieves substantially monotonic gray scale response. Embodiments digitally modulate the voltage across a photoreceptive material included in the spatial light modulator. The digital modulation scheme entails illuminating the photoreceptor with a series of light pulses propagating from an LCoS, in which the durations of the light pulses and their positions in time combine to produce binary-weighted equivalent rms voltages on the photoreceptor. The light pulses originate from a light-emitting diode or other switchable light source, and the timing of the light pulses is controlled such that they are emitted only when the associated LCoS is in a stable state. Emitting light pulses while the LCoS is in a stable state avoids non-monotonic behavior.

Optically addressed gray scale electric charge-accumulating spatial light modulator

A spatial light modulator has an array of elements organized into element rows and element columns and an array of electrodes organized into electrode rows and electrode columns to activate the array of elements. The modulator has pixel circuitry organized into circuit rows and circuit columns with the pixel circuitry being electrically coupled to the array of electrodes, such that there is at least one translation of either circuits in a column to electrodes in a row or circuits in a row to electrodes in a column.

Pixel circuit to electrode translation

A method, device and computer program are detailed for modulating write light. For a plurality of pixel locations of an electro-optic layer of an optical write valve and across each of a plurality of consecutive frames, a set of pixel data bits is modulated across a first and a second pulse width period of the frame. The first and second pulse width periods, and adjacent pulse periods of sequential frames, are separated from one another by a pulse-off period that is at least equal to a response time of the electro-optic layer during which no bits are modulated. Separately in each frame, write light is output from each of the plurality of pixel locations according to the modulated pixel data bits in the frame. In an embodiment, the set of pixel data bits are modulated by applying a voltage at a pixel location of the electro-optic layer in synchronism with illuminating a light source that illuminates that pixel location.

Pulse width driving method using multiple pulse

A pixel circuit includes a light emitting device, a storage device configured to represent a level of illumination, and a driving device used to drive the light emitting device. Configuring the storage device includes changing a voltage difference across the storage device to a level larger than a threshold voltage of the driving device. The driving device reduces driving of the light emitting device while the storage device is being configured. After the storage device has been configured, the driving device is permitted to drive the light emitting device to emit light having a luminance level corresponding to the level of illumination represented by the storage device.

Driving circuits for displays

A structure that possesses the combined properties of carrying signals through the provision of a series of electrical conductors, and by optical signals through the intermediary of a series of optical waveguides. This imparts a particular advantage thereto for the fabrication of optical data links, providing a convenient, compact method of interconnecting electrical paths to transducer chips and to waveguide structures. This approach solves the problem of connecting polymer waveguides to VCSEL (Vertical-Cavity-Surface-Emitting Laser) arrays, thereby avoiding the problem of damaging fragile wire bonds. A method is also provided which utilizes the foregoing structure.

Medium containing optical paths and electrically conducting paths for applications in high speed data links

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.

Active matrix oled voltage drive pixel circuit

There is provided a circuit for driving an organic light emitting diode (OLED). The circuit includes a current source for providing current to a first terminal of the OLED, and a generator for providing a variable voltage signal to a second terminal of the OLED to facilitate control of the current.

Data voltage current drive amoled pixel circuit

An active matrix display includes a plurality of pixels arranged in an array, a first transistor and a second transistor associated with each pixel, the first and second transistors positioned within the array for controlling current flow through each pixel, a light emitting diode associated with each pixel; and a storage capacitor associated with each pixel, wherein, during a time period for establishment of a threshold voltage on the storage capacitor for the first transistor, a voltage equal to the sum of the threshold voltage and a voltage for compensating for turnoff of the second transistor is established on the storage capacitor.

Active-matrix light emitting display and method for obtaining threshold voltage compensation for same

A pixel circuit comprises an organic light emitting diode (OLED), and a static memory for storing data that represents an operational state of the OLED. In alternative embodiments, a pixel circuit may include a complementary metal oxide semiconductor (CMOS) circuit for controlling the OLED, a protection circuit for protecting the CMOS circuit from an over-voltage condition, and a current source with a field effect transistor (FET) having a static gate to source voltage that is greater than a threshold voltage of the FET.

Low-power organic light emitting diode pixel circuit

There is provided a method for driving an organic light emitting diode (OLED) pixel circuit. The method includes applying a first signal to a terminal of the OLED when setting a state of the pixel circuit, and applying a second signal to the terminal when viewing the state. There is also provided a driver for an OLED pixel circuit, where the driver employs this method.

Growing community of inventors

Hopewell Junction, NY, United States of America

James Lawrence Sanford