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: Techniques are described for operating a display system comprising a light source and a scanning assembly. The light source includes a plurality of emitters arranged in a column and circuitry configured to drive the emitters based on image data. The scanning assembly includes a reflective surface facing the light source, the reflective surface being rotatable in at least one dimension. A control signal including periodic, non-linear pulses causes the reflective surface to rotate through a range of scan angles, thereby forming an output image based on reflection of emitted light. The image data is supplied to the light source in synchronization with the rotational movement of the reflective surface. Changes in rotation speed due to the non-linear nature of the control signal are compensated for by adjusting emission durations for different rows to provide different emission durations at different times based on changes in the linearity of the control signal.

Abstract: Systems and methods for controlling a display apparatus are provided. In one example, an apparatus comprises a display comprising a plurality of light emitting diodes (LED), a display control circuit configured to generate display control signals, and a test module configured to generate test control signals. In a test operation mode, at least one LED of the plurality of LEDs is configured to be controlled by the test control signals from the test module to conduct at least one test output current. The test module can determine electrical characteristics of the at least one LED based on the at least one test output current. The display control circuit can adjust the display control signals based on the electrical characteristics of the at least one LED.

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: 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: 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: 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 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: 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 provides pulse-width modulation (PWM), data loading, and calibration. The electronic display includes: a light emitting diode (LED); a driving transistor including a source connected to a first terminal of the LED; a first transistor including a source connected to a second terminal of the LED and a gate connected to a scan driver; a storage capacitor having a first node connected to a gate of the driving transistor, and a second node connected to a drain of the first transistor; a second transistor configured to selectively couple the first node of the storage capacitor to a data driver; and a third transistor configured to selectively couple the second node of the storage capacitor to a calibration driver so that the storage capacitor provides a gate voltage corresponding to a sum of the data voltage and the calibration voltage to the gate of the driving transistor.

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: Embodiments relate to driving first light emitting diodes (LEDs) of a first color to emit light during first subframes of emission frames, driving second LEDs of a second color to emit light during second subframes of emission frames, and driving third LEDs of a third color to emit light during the second subframes of emission frames. Light emitted from the first, second, and third LEDs is directed onto a mirror that reflects the light onto a plurality of pixel locations of an image field. The first, second, and third LEDs are aligned on an array of LEDs such that the first LEDs are at a first distance away from the second LEDs, and the first LEDs are at a second distance away from the third LEDs.

Abstract: Techniques are described for operating a display comprising an array of emitters arranged in at least one column. A data shifting circuit stores digital data or an analog representation thereof in a first storage element. The data shifting circuit outputs the digital data or analog representation multiple times to a display driver circuit, using a multiplexer. The first storage element can be a shift register or a capacitor. Digital data can be internally shifted within the data shifting circuit, through multiple shift registers, prior to output to the display driver circuit. An analog representation can be stored and read from the same capacitor without internal shifting. The display driver circuit drives a different emitter of the column each time. A scanning assembly including a reflective surface that receives light from the emitter array forms an output image by rotating the reflective surface in synchronization with driving of the emitters.

Abstract: Embodiments relate to driving first light emitting diodes (LEDs) of a first color to emit light during first subframes of emission frames, driving second LEDs of a second color to emit light during second subframes of emission frames, and driving third LEDs of a third color to emit light during the second subframes of emission frames. Light emitted from the first, second, and third LEDs is directed onto a mirror that reflects the light onto a plurality of pixel locations of an image field. The first, second, and third LEDs are aligned on an array of LEDs such that the first LEDs are at a first distance away from the second LEDs, and the first LEDs are at a second distance away from the third LEDs.

Abstract: Apparatuses and methods are presented relating to a plurality of current sources for generating a plurality of first bias currents to drive a plurality of LEDs and a plurality of measurement circuits for obtaining a plurality of first voltage measurements for the LEDs during a first test cycle. The current sources are further configurable to generate a plurality of second bias currents for driving the LEDs, and the measurement circuits are further configurable to obtain a plurality of second voltage measurements for the plurality of LEDs, during a second test cycle. A memory device is configured to store the first and second bias currents and first and second voltage measurements as a current-voltage (I-V) performance characteristic.

Abstract: Apparatuses and methods are presented relating to a plurality of current sources for generating a plurality of first bias currents to drive a plurality of LEDs and a plurality of measurement circuits for obtaining a plurality of first voltage measurements for the LEDs during a first test cycle. The current sources are further configurable to generate a plurality of second bias currents for driving the LEDs, and the measurement circuits are further configurable to obtain a plurality of second voltage measurements for the plurality of LEDs, during a second test cycle. A memory device is configured to store the first and second bias currents and first and second voltage measurements as a current-voltage (I-V) performance characteristic.

Abstract: Techniques are described for operating a display system comprising a light source and a scanning assembly. The light source includes a plurality of emitters arranged in a column and circuitry configured to drive the emitters based on image data. The scanning assembly includes a reflective surface facing the light source, the reflective surface being rotatable in at least one dimension. A control signal including periodic, non-linear pulses causes the reflective surface to rotate through a range of scan angles, thereby forming an output image based on reflection of emitted light. The image data is supplied to the light source in synchronization with the rotational movement of the reflective surface. Changes in rotation speed due to the non-linear nature of the control signal are compensated for by adjusting emission durations for different rows to provide different emission durations at different times based on changes in the linearity of the control signal.

Abstract: Systems and methods for controlling a display apparatus are provided. In one example, an apparatus comprises a display comprising a plurality of light emitting diodes (LED), a display control circuit configured to generate display control signals, and a test module configured to generate test control signals. In a test operation mode, at least one LED of the plurality of LEDs is configured to be controlled by the test control signals from the test module to conduct at least one test output current. The test module can determine electrical characteristics of the at least one LED based on the at least one test output current. The display control circuit can adjust the display control signals based on the electrical characteristics of the at least one LED.

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.