Abstract: The present invention describes a method and apparatus for measuring the voltage and current characteristics of the OLED pixel as it ages and correlating the measured data to the decrease in quantum efficiency and changes in OLED impedance over the life of the OLED, so that corrections can be made to the image drive system to prevent image sticking and color point drift. The method and apparatus of the present invention do not require any additional circuitry or changes in the display design. The circuitry of the present invention is implemented in the display driver integrated circuit (IC) chips. The basis of the invention is the luminance-current-voltage (LIV) curves which characterize the OLED materials over their life time. A series of these curves are stored in memory representing a OLED material at various ages.

Abstract: A stabilized feedback display system and method for maintaining uniform pixel luminances in a display device. System includes a display device having a plurality of emissive picture elements (pixels) each formed from at least one electronic circuit device, a display driver circuit receiving a raw input image signal from an external image source and applying a corrected image signal to the display, a display luminance detector generating at least one display device luminance value, and a processing logic unit receiving the at least one display device luminance value and communicating information to the display driver circuit, the display driver circuit using this communicated information to generate a transformation for generating the corrected image signal from the raw input image signal.

Abstract: System, device, and method for operating active-matrix emissive pixel display device. Method includes storing calibration value for pixels and gray levels displayed by pixels in memory; storing transformation in memory for transforming first representations of gray level values to second representations; receiving first gray level representations of image pixel gray level values; transforming first representations to second representations for each pixel; generating image data and control signals for driving pixels during present display frame time; generating integrated photon flux signal for pixels in display indicative of integrated photon flux during portion of present display frame time; comparing plurality of integrated photon flux signals with calibration values on pixel-by-pixel basis and generating plurality of comparison results indicating difference; and identifying deviation for each pixel and directing change in stored transformation to be applied during subsequent time.

Abstract: Self-calibrating emissive pixel circuit, device and method for operating pixel. Method for operating includes: establishing sensor capacitor at predetermined starting voltage, delivering current to photon emitting device to cause photons to be emitted at predetermined target photon emission level, exposing sensor having electrical properties that vary according to photon flux on sensor to the emitted photon emission during at least portion of display frame time, permitting sensor capacitor to either charge or discharge from predetermined starting state through the sensor so that portion of frame time and resistance of sensor during portion of frame time determine amount of charge on sensor capacitor, measuring voltage or charge remaining on sensor capacitor at end of portion of frame time as indication of integrated photon flux and pixel luminance, and modifying image voltage and/or current applied to pixel during any subsequent display frame time using measured voltage as feedback parameter.

Abstract: System and method for controlling luminance of pixel in display. Method includes storing transformation between digital image gray level value and display drive signal that generates luminance from pixel corresponding to digital gray level value; identifying target gray level value for particular pixel; generating display drive signal corresponding to identified target gray level based on stored transformation and driving particular pixel with drive signal during first display frame; measuring parameter representative of actual measured luminance of particular pixel at a second time after the first time; determining difference between identified target luminance and actual measured luminance; modifying stored transformation for particular pixel based on determined difference; and storing and using modified transformation for generating display drive signal for particular pixel during frame time following first frame time.

Abstract: An emissive pixel device having integrated luminance sensor and a method of operating an emissive pixel device having an integrated luminance or photon flux sensor. Device includes light or photon emitting device, drive circuit generating current to drive light emitting device to predetermined luminance corresponding to an image voltage and applying drive current to light emitting device during frame time, photo sensor that exhibits change in electrical characteristic in response to change in incident photon flux disposed near the light emitting device to intercept measurable photon flux when light emitting device is in emitting state, charge storage device coupled with sensor for accumulating or releasing charges and exhibiting capacitance charge and voltage proportional to the charge at a time; and control circuit controlling charging and discharging of charge storage device in response to changes in electrical characteristics of sensor during at least a portion of the frame time.

Abstract: Information appliance device and method for operating display associated with information appliance. Information appliance includes display device comprising plurality of active-matrix pixels arranged as two-dimensional array, each pixel including a photon emitter, emitter drive circuit receiving input image data for each pixel and generating pixel drive signal intended to produce a corresponding target pixel luminance during frame time, and emitter luminance sensor and measurement circuit that measures electrical parameter indicative of actual luminance of each pixel over portion of measurement display frame time; and display logic coupled to display and receiving pixel luminance related electrical parameter for each pixel and generating correction for application subsequent time period to input image data for each pixel based on difference between target pixel luminance and measured pixel luminance. Photon emitter may be OLED, electroluminescent, plasma or other emissive device in flat panel display.