Service Life Extension in Micro-LED Displays

LED driving method for HUD displays that reduces power consumption and increases LED lifespan. The method involves monitoring temperature and display duration of LED partitions in the HUD. If a partition exceeds a temperature threshold, it is temperature controlled. If a partition has display stagnation exceeding a threshold, it is static protected by adjusting brightness. This manages LED temperature and prevents burnout, while saving power by dynamically adjusting brightness when displays stall.

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LED screen display correction method and system to improve display brightness and extend screen life. The method involves dynamically adjusting the temperature of the LED screen's light condensing elements instead of increasing luminous power when brightness decreases. This prevents high power consumption that shortens screen life. The method obtains the LED element parameters, calculates brightness attenuation and initial floating values, then corrects the floating value based on environmental factors. If brightness is still below target, the screen temperature is adjusted to compensate.

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Intelligent method and system for adjusting the brightness of a light-emitting diode (LED) to improve accuracy and efficiency. The method involves monitoring LED light output and temperature, extracting feature vectors, curve fitting to create an aging relationship, optimizing brightness strategies based on environmental lighting changes, and generating pulse width modulation signals for the LED driver. It considers factors like LED aging, temperature, and ambient lighting to adaptively adjust brightness for better user experience and LED lifespan.

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Method for correcting color changes in LED displays due to temperature rise. The method involves measuring temperature and luminance of the LEDs at different temperatures, calculating brightness-to-temperature time constants and ratios, and using those values to convert input color values into corrected output values that compensate for temperature-induced brightness changes. This allows maintaining consistent colors as the LEDs heat up.

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LED chips with improved reliability, moisture resistance, and flexibility for additional features by using a passivation layer around the mesa sidewalls of the LED structure. The passivation layer, made of materials like silicon nitride, seals the LED mesa perimeter to prevent undercutting during etching and reduce moisture ingress. This allows for better reliability, reduced risk of damage, and the ability to add features like dielectric reflective layers and DBR reflectors to the chip.

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A method to improve display quality and reduce power consumption in electronic devices with displays that have pixels that can be individually controlled. The method involves determining decay rates for the pixels based on their luminance values. The luminance values for the pixels are adjusted based on their decay rates to compensate for aging and variability. This prevents image sticking, extends display life, and reduces power consumption.

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Compensating power supply voltage drop in MicroLED displays to improve brightness and color accuracy. The compensation involves detecting the voltage drop caused by current through off-chip resistors when the display is lit. This drop is compensated by adding an equal voltage to the control signal for the LEDs. The compensation can be done digitally using an algorithm or analog circuits. The algorithm involves establishing a model of the display and power supply to calculate the required compensation.

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An electronic device with a protective layer that prevents moisture and air intrusion and reduces the risk of delamination or damage to the light-emitting units due to thermal expansion mismatch. The protective layer has a Young's modulus less than or equal to 20 MPa. This low modulus allows the protective layer to deform and conform to the substrate and light-emitting units, preventing gaps that allow moisture and air ingress. It also reduces peeling and delamination. The low modulus also allows the protective layer to flex without cracking when pressed, preventing damage. The low modulus protective layer can be combined with wavelength conversion particles or reflective structures in the layer to simplify manufacturing and improve color saturation and efficiency.

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Compensating the display junction temperature of LED digital tubes in electronic displays to prevent red shift and improve display quality. The method involves monitoring the surface temperature and current of the LEDs in the tubes. Based on the measured values, it calculates the junction temperature of the LEDs. If the junction temperature is too high, it adjusts the delay time of the display control signal to reduce switching losses and lower the junction temperature. This prevents redshift. It also extends the display control signal to avoid multiple simultaneous LED switches. This increases flux but risks afterglow. The extension time is calculated to balance these effects.

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Micro-LED display panel with redundancy to improve yield and reliability. The display has micro-LEDs arranged in sub-pixels on a driving substrate, with some sub-pixels containing two series-connected micro-LEDs of the same color. In normal sub-pixels, both LEDs emit light, but if one LED fails, only the working LED emits light. Redundancy positions allow extra LEDs to parallel connect if both originals fail. This compensates for failed LEDs and maintains full sub-pixel brightness. The redundancy prevents single LED failures from affecting display quality.

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Method to reduce frequency of LED display screen correction by intelligently predicting brightness decay and temperature impact. The method involves collecting historical brightness and temperature data for each display area over time. From this, it determines a brightness decay rate and average temperature for each area. Using these values, it predicts the optimal temperature for each area to minimize decay. The actual display temperature is compared to this predicted optimal temperature. If higher, it triggers cooling measures like fan or air conditioning. If the display is working too long, it calculates an optimal shutdown time based on working hours, temperature difference, and a weighting factor.

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Display panel with improved heat dissipation for micro-LEDs to avoid efficiency loss and extend lifespan. The panel has pixel units with driving circuits between the substrate and light-emitting components. For units with micro-LEDs, the circuit includes a thin-film transistor connected to a metal structure. This forms a heat dissipation path from the micro-LED to the metal layer away from the substrate.

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Thermal protection circuit for LEDs that allows controlling LED temperature without measuring the actual junction temperature. The circuit monitors the voltage across the LED to determine the junction temperature. It then digitally modulates the drive current duty cycle to adjust the LED brightness and maintain a desired temperature. This avoids the issues of direct temperature sensing like needing thermocouples or assuming driver and LED temps match. It also allows flexible LED placement and prevents chromaticity shift by maintaining constant peak current.

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A micro-LED display that can sustain high brightness without overheating, which can lead to color degradation and reduced lifetime, is used. The display uses micro-caps to thermally insulate the tiny LEDs from the substrate. The micro-caps create sealed chambers around each LED that can be filled with gas or vacuum. This prevents heat buildup and protects the color conversion layers. The display also has color material layers on the micro-caps to enhance color performance.

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Display panel with improved luminous efficiency and longer device life without using lithium fluoride. The panel has a stacked inorganic packaging layer above the light-emitting device. The stack has three sublayers with refractive indices in specific order and difference. The middle sublayer has higher index than top and bottom layers. This enhances light reflection inside the microcavity to increase luminous intensity. It improves efficiency compared to two sublayer stacks. The three sublayer stack also better protects the device from water and oxygen compared to single or double stacks.

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Display panel with redundancy scheme incorporating micro-LEDs to enable high-resolution micro-LED displays with high yield and longer lifetime. The display panel includes an array of micro-LED devices in each pixel and multiple top electrodes to provide redundancy and repair capability for faulty micro-LEDs. This allows the detection and bypassing of defective micro-LEDs during panel manufacturing. The bottom electrodes are bonded to pairs of micro-LEDs that emit the same color. The top electrodes connect one micro-LED in each pair to the ground line. If a micro-LED is faulty, the other micro-LED in the pair compensates for it. The display also uses an integrated test method where imaging after transfer detects faulty micro-LEDs for replacement before passivation and top electrode formation.

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A method to prevent display brightness from decreasing below a target level as light-emitting diodes (LEDs) age. The method involves initially setting the LED output higher than the target brightness when the LEDs are turned on. This compensates for luminance loss due to aging. Subsequent brightness corrections account for both aging and initial overdrive. By starting higher, the LEDs can be replaced at the target lifetime even if they degrade faster from initial overdrive. This prevents brightness from dropping below the target.

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Dynamic power supply adjustment for microLED arrays to improve efficiency and reduce losses compared to fixed high voltage supplies. The power supply voltage is dynamically adjusted based on operating conditions like temperature and current amplitude to match the actual required voltage. This avoids excessive fixed voltage that wastes power in the current source and causes losses. The voltage adjustment is determined using data on the LED forward voltage and process spread.

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A power control system for LED modules that compensates for temperature effects to maintain constant light output as the module heats up. The system measures the module temperature and SMPS power consumption. It then adjusts the power supplied to the module based on the temperature and power data to compensate for temperature-related efficiency loss. This prevents light output degradation due to self-heating and ambient temperature increases. The power compensation keeps the module's light output consistent as it warms up.

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Display device with improved luminance correction for reducing display unevenness in the initial stages of luminescent element degradation. The display has a correction circuit that converts input luminance signals to target values, calculates output gradations using a degradation index, then corrected luminance. It calculates stresses on the element from the corrected luminance: current stress based on a reference current and accumulated time, and CB stress based on a reference current or time. These stresses update the degradation index. This allows accurate correction even when initial degradation deviates from models due to factors like carrier balance loss.

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