Abstract: Embodiments relate to testing a plurality of LEDs by applying a voltage difference between anode electrodes and cathode electrodes of the plurality of LEDs using transistors and probe pads on a display substrate. The anode electrodes of the plurality of LEDs are connected to a first probe pad via clamping transistors, and the cathode electrodes are connected to a second probe pad. Responsive to applying the voltage difference, it is determined whether the plurality of LEDs satisfy a threshold level of operability. The display substrate also includes driving transistors and switching transistors connected to the plurality of LEDs, the driving transistors and switching transistors used during operating mode.

Abstract: An electronic display uses pulse-width modulation (PWM) to drive light emitting devices (LEDs) with reduced power consumption. A modified digital word including a modified sequence of bits is generated by modifying a bit sequence of a greyscale value for a sub-pixel. The modified bit sequence includes fewer transitions from a first voltage level to a second voltage level higher than the first voltage level than the bit sequence of the grayscale value. A modified sequence of pulses is generated based on ordering pulses of the PWM signal according to the modified bit sequence. The modified digital word and the modified sequence of pulses are used to control a light emitting device of the electronic display. The reduction in voltage level transitions results in reduced charging of a storage capacitor in the control circuit for the LED, while maintaining brightness level as specified by grayscale value.

Abstract: Embodiments relate to testing a plurality of LEDs by applying a voltage difference between anode electrodes and cathode electrodes of the plurality of LEDs using transistors and probe pads on a display substrate. The anode electrodes of the plurality of LEDs are connected to a first probe pad via clamping transistors, and the cathode electrodes are connected to a second probe pad. Responsive to applying the voltage difference, it is determined whether the plurality of LEDs satisfy a threshold level of operability. The display substrate also includes driving transistors and switching transistors connected to the plurality of LEDs, the driving transistors and switching transistors used during operating mode.

Abstract: Disclosed herein are display systems and techniques for operating a display in a display system. An output image is formed by scanning a column of light emitters such that emitters in different rows of the column contribute to a same location in the output image. The emitters are driven using pulse-width modulation (PWM). PWM pulses are applied in synchronization with the scanning to cause emitters to emit light at an intensity corresponding to an illumination parameter. The driving includes generating, based on an illumination parameter, a PWM pulse by applying an analog signal in combination with applying a digital signal. The analog signal controls an amplitude of the PWM pulse. The digital signal controls a duration of the PWM pulse.

Abstract: A method and system for calibrating brightness variation in a display involve measuring brightness levels of light emitters in the display. The light emitters are divided into different groups based on the measured brightness levels. Each group is assigned a sub-frame duration. Groups with higher brightness are assigned shorter sub-frame durations than groups with lower brightness. Calibration information is stored for driving the light emitters such that during a frame period of the display, the light emitters are activated for durations corresponding to the sub-frame duration of their corresponding group.

Abstract: Described herein are ILED displays including redundancy in micro-light emitting diode (micro-LED) dies and methods of manufacturing the ILED displays. A micro-LED die emits light of a particular wavelength. The redundancy is added during manufacturing if defective micro-LED dies are identified. Additional micro-LED dies are included in inoperable sub-pixel assemblies to repair the inoperable sub-pixel assemblies that are identified to include defective micro-LED dies. An ILED display therefore includes at least one repaired sub-pixel assembly that includes two defective micro-LED dies and an operable micro-LED die that are coupled to separate branches of a current path from a current source.

Abstract: Techniques are described for collecting feedback on a display comprising a plurality of emitters arranged in a column. Each emitter is driven by a respective emitter cell that generates a driving current for the emitter based on digital data or an analog representation thereof. The digital data or analog representation is sequentially shifted through the entire column. An electrical signal associated with a last emitter to be driven based on the digital data or analog representation is measured, along a feedback path formed by selectively opening or closing a first switch and a second switch, which are respectively connectable to an anode and a cathode of the last emitter. Since each emitter cell contributes to the electrical signal, the value of the electrical signal is indicative of whether there is a problem with an emitter cell somewhere in the column. The subsequently driving of the emitters is adjusted accordingly.

Abstract: Techniques are described for operating a display comprising an array of emitters arranged in at least one column. Data is shifted through the emitters of the column using a data shifting circuit. The data can be shifted sequentially, one emitter at a time. The data shifting circuit includes storage elements for temporary storage of the data as it is shifted down the column. The data can be stored as a charge on a capacitor, where the capacitor is charged to a particular voltage according to a current from a current mirror. The shifting can be performed in synchronization with scanning of the emitters by a scanning assembly, where the scanning produces an output image for viewing by a user.

Abstract: An active matrix display wherein each cell comprises: two thin-film transistors (TFTs) connected in series, the first TFT having its drain connected to a high supply line and the second TFT having its source connected to a low supply line. Gates of the first and second TFTs are selectively connected to respective first and second data driver signals under the control of a scan line signal. A storage capacitance is connected to a node joining the first and second TFT. A driving TFT has a gate connected to the joining node and is connected to drive a light emitting device with a bias current. In one embodiment, the first and second TFTs are sized relative to one another and the first and second data driver signal voltages are related proportionally, so that the data driver signals and the bias current are related to one another by a function substantially independent of a threshold voltage of the driving TFT.

Abstract: An active matrix display where in one embodiment each cell comprises: a driving circuit for providing current to light emitting devices placed in the cell under the control of a data driver signal, a first light emitting device location connected to the driving circuit and a second light emitting device location connected in series to the first light emitting device location. A first thin-film transistor (TFT) is connected in parallel with the first light emitting device location and a second TFT is connected in parallel with the second light emitting device location, its gate node connected to the gate node of the first TFT. One terminal of a third TFT is connected to the gate nodes of the first and second TFTs and selectively connects a control signal to the first and second TFTs under the control of a scan driver signal. The control signal determines which of a first or second light emitting device placed in the cell emits light when the driving circuit provides current.

Abstract: A scanning type display device includes a light source that includes multiple rows and columns of light emitters. The display device also includes a rotatable mirror that projects light to different areas of an image field as the mirror rotates. There can be a redundant number to light emitters in the light source to increase the brightness of the pixels in the image field. A data driver may replicate and shift data values among light emitters of the same columns. The light emitters may operate in conjunction with the mirror in a synchronized manner. Owing to the shift in data value and the rotation of the mirror, the mirror may first project light from a first light emitter to a pixel and may then project light from a second light emitter with the same brightness level to the same pixel. The shifting may continue for additional light emitters.

Abstract: Multiple rows of light sources emitting the same color are arranged to provide redundancy against defective light sources. The light sources are used in conjunction with an optical element to display on a screen. Although only a single row of light sources is needed for each color, multiple rows of light sources are provided for each color and the optical element scans vertically across rows to produce an image. When a defective light source is detected, light sources surrounding the defective light source are overdriven to compensate for the defective light source.

Abstract: Embodiments relate to testing LEDs by applying a voltage difference between anode electrodes and cathode electrodes of the LEDs using transistors and probe pads and determining whether the LEDs satisfy a threshold level of operability. A final substrate has transistors that apply the voltage difference to the LEDs via conductive traces and probe pads during testing mode. A gate voltage is applied to gate terminals of the transistors, a first voltage is applied to anode electrodes of the LEDs, and a second voltage is applied to cathode electrodes of the LEDs. After applying the voltages, turning on of the LEDs is observed. Embodiments also relate to testing current leakage in the final substrate with the transistors and the LEDs.

Abstract: An electronic display includes a multi-layer structure that reduces form factor and provides optimization of the electronic display on a per layer basis. The electronic display includes a driver layer, a control layer, and an interposer layer between the driver layer and the control layer. The driver layer includes one or more drivers to provide control signals. The control layer includes control circuits configured to drive light emitting diodes (LEDs) under control of the control signals from the driver layer. The interposer layer is between the driver layer and the control layer. The interposer layer includes electrical connections between the one or more drivers of the driver layer and the control circuits of the control layer to transmit the control signals from the driver layer to the control layer.

Abstract: An active matrix display where in one embodiment each cell comprises: a driving circuit for providing current to light emitting devices placed in the cell under the control of a data driver signal, a first light emitting device location connected to the driving circuit and a second light emitting device location connected in series to the first light emitting device location. A first thin-film transistor (TFT) is connected in parallel with the first light emitting device location and a second TFT is connected in parallel with the second light emitting device location, its gate node connected to the gate node of the first TFT. One terminal of a third TFT is connected to the gate nodes of the first and second TFTs and selectively connects a control signal to the first and second TFTs under the control of a scan driver signal. The control signal determines which of a first or second light emitting device placed in the cell emits light when the driving circuit provides current.

Abstract: An active matrix display where in one embodiment each cell comprises: a driving circuit for providing current to light emitting devices placed in the cell under the control of a data driver signal, a first light emitting device location connected to the driving circuit and a second light emitting device location connected in series to the first light emitting device location. A first thin-film transistor (TFT) is connected in parallel with the first light emitting device location and a second TFT is connected in parallel with the second light emitting device location, its gate node connected to the gate node of the first TFT. One terminal of a third TFT is connected to the gate nodes of the first and second TFTs and selectively connects a control signal to the first and second TFTs under the control of a scan driver signal. The control signal determines which of a first or second light emitting device placed in the cell emits light when the driving circuit provides current.

Abstract: An active matrix display wherein each cell comprises: two thin-film transistors (TFTs) connected in series, the first TFT having its drain connected to a high supply line and the second TFT having its source connected to a low supply line. Gates of the first and second TFTs are selectively connected to respective first and second data driver signals under the control of a scan line signal. A storage capacitance is connected to a node joining the first and second TFT. A driving TFT has a gate connected to the joining node and is connected to drive a light emitting device with a bias current. In one embodiment, the first and second TFTs are sized relative to one another and the first and second data driver signal voltages are related proportionally, so that the data driver signals and the bias current are related to one another by a function substantially independent of a threshold voltage of the driving TFT.

Abstract: A display comprises a matrix comprising a plurality of N rows divided into a plurality of M columns of cells, each cell including a light emitting device; a scan driver providing a plurality of N scan line signals to respective rows of said matrix, each for selecting a respective row of the matrix to be programmed with pixel values; and a data driver providing a plurality of M variable level data signals to respective columns of the matrix, each for programming a respective pixel within a selected row of the matrix with a pixel value. A pulse driver provides a plurality of N driving signals to respective rows of the matrix, each driving signal comprising successive sequences of pulses enabling the cells to emit light according to their programmed pixel values during respective sub-frames of successive frames to be displayed.

Abstract: This disclosure provides systems, methods and apparatus for controlling the states of a light modulator used in displays. A display apparatus includes pixels circuit for controlling the state of operation of dual actuator light modulators. The pixel circuit can be implemented using three transistors and a capacitor. In particular, the pixel circuit can include a charge-discharge transistor, a data transistor, and a feedback transistor. The charge-discharge transistor is used to both selectively charge and selectively discharge an output node of the pixel circuit coupled to the light modulator. The data transistor enables loading a data capacitor with data voltage representative of image data. The feedback transistor provides positive feedback to allow the output node to be charged to the actuation voltage via the charge-discharge transistor.

Abstract: This disclosure provides systems, methods, and apparatus for providing pixel circuits for controlling the state of operation of light modulators in a display device. The state of operation of the light modulator can be controlled by the pixel circuit based on a data voltage stored in a data storage element of the pixel circuit. The pixel circuit includes an actuation circuit for providing an actuation voltage to the light modulator and a feedback circuit for providing a positive feedback voltage from an output node of the actuation circuit to an input node of the actuation circuit. In some implementations, the feedback circuit includes the data storage element connected between the input node and the output node.