Abstract: A method of touch detection for a projected capacitive (PCAP) touch sensor includes generating a set of unique signal frequencies, energizing each row with a unique frequency according to a rotating frequency scheme, receiving column signals as a summation of the row frequencies, processing the column signals using an algorithm such as a fast Fourier transform (FFT) algorithm to deconstruct each column signal, and analyzing the relative magnitudes of the unique row frequencies to identify a change in magnitude to indicate a touch event on the sensor. The method may be implemented in a touch display device, for instance in aircraft avionics displays requiring redundancy.

Abstract: A keypanel assembly includes a light-emitting diode (LED) attached to a substrate. A switch is attached to the substrate. A control button is configured to actuate the switch. The control button permits light from the LED to pass through the control button to an outer surface of the control button to illuminate control symbology disposed thereon. An isolating structure ensures light emitted by the LED only illuminates the control symbology on the control button.

Abstract: A method of improving response time of a display element in a display is disclosed. According to the method, a command input is provided that represents a desired response of the display element. The command input is modified, using a compensation function, to produce a command output to be sent to the display element. The compensation function uses the command input and a modeled luminance of the display element in a present state and at least one previous state to compute the command output. The command output is transmitted to the display element.

Abstract: A variably controlled LCD backlight is disclosed. The backlight includes a first light source that emits light within a first spectral power distribution and has a first radiant power output. A second light source emits light within a second spectral power distribution and has a second radiant power output. A detector detects the first and second radiant power outputs. A processor is connected to the detector and calculates chromaticity and luminance values of the emitted light based on the first and second radiant power outputs. The processor compares the calculated chromaticity and luminance values with desired chromaticity and luminance values, respectively. A controller is operationally connected to the processor and adjusts one or more of the first radiant power output and the second radiant power output in response to a difference between the calculated chromaticity and luminance values and the desired chromaticity and luminance values.

Abstract: A method of backlighting a flat panel display over an expanded dimming range includes providing a backlight including multiple cold cathode fluorescent lamps positionable directly behind a diffuser. Each of multiple drive circuits is adapted to independently adjust arc current of at least one of the multiple cold cathode fluorescent lamps in order to change the luminance output of the at least one of the cold cathode fluorescent lamps. Control signals are provided to each of the multiple drive circuits to separately control luminance output of different cold cathode fluorescent lamps such that at the same instant the different cold cathode fluorescent lamps are driven to substantially different luminance intensities, thereby allowing a reduction of an overall minimum luminance provided by the backlight and expanding the dimmable range of the backlight. A backlight implementing the methods of the invention is also disclosed.