Abstract: A liquid crystal display (LCD) has a voltage generating circuit, a voltage regulating circuit, and a liquid crystal panel. The voltage generating circuit provides the liquid crystal panel with positive gray voltages and negative gray voltages. The voltage regulating circuit creates a compensating voltage lookup table recording compensated voltages according to the luminance, the positive gray voltage and the negative gray voltage of every gray level. The voltage regulating circuit regulates the positive gray voltage and the negative gray voltage using the compensated voltages recorded in the compensating voltage lookup table.

Abstract: A method for adjusting a common voltage of an LCD device includes providing an LCD device and a photodetector, obtaining variable parameters Ya, Yb and Yc, the variable parameters Ya, Yb and Yc respectively denoting flicker intensity of the LCD device when the common voltages are parameters Va, Vb and Vc, Vb exceed Va, and is less than Vc, when Yb exceeds Yc and is less than Ya, increasing the parameters Va, Vb and Vc respectively and repeating the two steps, when Yb exceeds Ya and is less than Yc, decreasing the parameters Va, Vb and Vc respectively and repeating the two steps, and when Yb is less than or equals Ya and is less than or equals Yc, setting an arbitrary value between Va and Vc as an optimum common voltage of the LCD device.

Abstract: An exemplary data driving circuit includes a data register, a counter, and a comparator. The data register is configured for receiving serial gray level signals in turn, and outputting the plurality of gray level signals in parallel. The counter is configured for outputting counting signals. The comparator is configured for receiving the gray level signals and the counting signals, and outputting pulse voltage signals according to the gray level signals and the counting signals. A variety of duty ratios of the pulse voltage signals correspond to a variety of gray levels.

Abstract: An exemplary backlight modulation circuit includes a backlight source, a backlight driving circuit, a rough modulation key, a fine modulation key, a scaler, and an illumination modulation signal processing circuit. The backlight driving circuit is configured for driving the backlight source. The rough modulation key and the fine modulation key are configured for generating a rough triggering signal and a fine triggering signal. The scaler is configured for receiving the rough triggering signal and the fine triggering signal, and generating an illumination modulation signal. The illumination modulation signal processing circuit is configured for receiving the illumination modulation signal, and processing the illumination modulation signal to generate one of a rough modulation controlling signal to modulate illumination of the backlight source in a large range and a fine modulation controlling signal to modulate the illumination of the backlight source in a small range.

Abstract: An exemplary liquid crystal display includes a substrate, a light source, and a color feedback system. The light source includes light emitting diodes. The color feedback system includes either one color sensor or plural color sensors. In one example, a single color sensor is disposed on the substrate and samples the light at the substrate. The color feedback system adjusts the brightness of the light emitting diodes according to the sampling signals of the color sensor.

Abstract: A liquid crystal display panel (21) includes a display area (210) and an image sensing system (23). The image sensing system is arranged in the display area. The image sensing system is capable of sensing ambient light and converting the ambient light into image signals. The display area is capable of displaying images corresponding to the image signals.

Abstract: An exemplary digital photo frame includes an image memory configured for storing a display image, a display device configured for reading and displaying the display image, an infrared sensor configured for detecting infrared light, generating a first detecting signal when the infrared light is detected, generating a second detecting signal when the detected infrared light is no longer detectable, and a camera control circuit including a reference image therein. The camera control circuit generates an instant image and compares the instant image with the reference image when the first detecting signal is generated. The digital photo frame is configured to operate in a monitor mode or a display mode according to a comparing result when the infrared light is detected.

Abstract: An exemplary backlight control circuit for changing a brightness of a light source includes a coarse adjusting circuit and a fine adjusting circuit. The coarse adjusting circuit is configured to coarsely adjust a DC voltage according to one received coarse adjusting signal. The fine adjusting circuit is configured to finely adjust the DC voltage according to one received fine adjusting signal. A change of the DC voltage generated by the coarse adjusting circuit is greater than another change of the DC voltage generated by the fine adjusting circuit.

Abstract: An exemplary backlight modulation circuit (2) includes a first modulation section (220), a second modulation section (221), and a backlight modulation section (240). The first modulation section is configured to generate a first backlight modulation signal. The second modulation section is configured to generate a second backlight modulation signal. The backlight modulation section is configured to modulate illumination of an associated backlight module according to the first and second backlight modulation signals.

Abstract: An exemplary display device includes a monitor, a camera, a comparison circuit connected to the camera, and a control circuit connected to the control circuit and the monitor. The camera is capable of capturing a plurality of instantaneously captured images. The comparison circuit is capable of generating a positive result when one of the instantaneously captured images matches a pre-stored reference image, and generating a negative result when no instantaneously captured images match the reference image. The control circuit is configured for generating a first instruction to turn on the monitor according to the positive comparison result and to turn off the monitor according to the negative comparison result.

Abstract: A common voltage generating circuit includes a square wave generating unit, a diode, a NOT gate, a first capacitor, a second capacitor, a third capacitor, a first resistor, a second resistor, and an output terminal. The square wave generating unit includes an output terminal, which is coupled to the output terminal of the common voltage generating circuit via the first resistor, a positive terminal of the diode, a negative terminal of the diode, and the second resistor in series. The output terminal of the square wave generating unit is coupled to the negative terminal of the diode via the NOT gate and the first capacitor. The positive terminal of the diode is grounded via the second capacitor, and the output terminal of the common voltage generating circuit is grounded via the third capacitor. A duty ratio of the output square wave generating unit is capable of being modulated.

Abstract: An exemplary liquid crystal display includes a liquid crystal panel having a plurality of pixel units arranged in rows, a scanning circuit configured to activate the pixel units row by row by outputting a plurality of corresponding scanning signals, a data circuit configured to provide data voltage signals to the activated pixel units, and a common voltage circuit. Each pixel unit includes a coupling member. When a row of pixel units is activated, all the coupling members in the row of pixel units cooperatively generate a coupling signal according to the data voltage signals applied to the activated row of pixel units, and superpose the coupling signal to the corresponding scanning signal so as to form a feedback signal. The common voltage circuit adjusts a reference voltage signal according to the feedback signal, and provides at least one common voltage signal to the pixel units.

Abstract: A backlight modulation circuit includes an illumination controlling signal generating circuit, an illumination control signal separating circuit, and an illumination modulation circuit. The illumination controlling signal generating circuit is configured for receiving an modulation signal and generating an illumination controlling signal according to the modulation signal. The illumination control signal separating circuit is configured for separating the illumination controlling signal into a first modulation signal and a second modulation signal. The illumination modulation circuit is configured for modulating illumination of a backlight module according to the first and second modulation signals.

Abstract: An exemplary liquid crystal display (300) includes a liquid crystal panel (301) receiving reference voltages; and a polarity resetting circuit (354) receiving display signals from external circuit and resetting the received display signals to attain resetted display signals, which makes the voltage difference between the resetted display signals and the previous frame display signals smaller than that between the corresponding received display signals and the previous frame display signals.

Abstract: An exemplary backlight control circuit includes an inverter, a pulse width modulation (PWM) circuit, and a frequency setting circuit. The inverter is configured to provide an alternating current voltage to a lamp. The PWM circuit is configured to provide a pulse control signal to the inverter. The frequency setting circuit configured to regulate a frequency of the pulse control signal provided by the PWM circuit according to an environment temperature.

Abstract: An exemplary backlight control circuit includes an inverter, a pulse width modulation (PWM) circuit, and a frequency setting circuit. The inverter is configured to provide an alternating current voltage to a lamp. The PWM circuit is configured to provide a pulse control signal to the inverter. The frequency setting circuit is configured to regulate a frequency of the pulse control signal provided by the PWM circuit according to a temperature of the lamp.

Abstract: An exemplary power control circuit (24) includes a scaler circuit (245) configured for outputting a control signal, a voltage converter (27) configured for converting a received voltage into a plurality of desired voltages, a first control unit (28), a second control unit (29), and a coupling circuit (26). The first control unit is configured for controlling whether a first voltage is applied to the voltage converter. The second control unit is configured for controlling whether to transmit a second voltage applied thereto. The coupling circuit is between the first and second control units. The coupling circuit enables the second control unit to function ahead of the voltage converter according to the control signal.

Abstract: A liquid crystal display (300) includes a liquid crystal panel (310) having a plurality of pixels P(i, j) arranged in a matrix, a brightness identification unit (343) configured for identifying a brightness of an image element to be displayed by at least one pixel, a polarity analyzing unit (344) configured for analyzing a result of the identification, and a data circuit (330). The polarity analyzing unit is also configured for generating a composed binary signal having a first binary portion the same as the primary display signal and an additive second binary portion. The data circuit is configured to provide a data voltage to drive the pixel according to the signal. A value of the data voltage is determined by a first binary portion of the composed binary signal, and a polarity of the pixel is determined by the second binary portion of the composed binary signal.

Abstract: An exemplary liquid crystal display includes an image signal analyzing circuit, a frame rate controlling circuit, an image signal processing circuit, and an output circuit. The image signal analyzing circuit is configured for judging whether images corresponding to input signals have flicker by analyzing pixel intensities and pixel voltage polarities of the input signals of each frame, and outputting controlling signals. The frame rate controlling circuit is configured for controlling a frame rate of output signals according to the controlling signals received from the image signal analyzing circuit. The image signal processing circuit is configured for inserting black image signals into input signals if the images corresponding to input signals have flicker. The output circuit is configured for outputting image signals according to signals transmitted from the frame rate controlling circuit and the image signal processing circuit.

Abstract: An exemplary liquid crystal display (200) includes a liquid crystal panel (201) having a plurality of pixel units (240), a scanning circuit (202) configured to activate the pixel units, a data circuit (203) configured to provide data voltage signals the pixel unit via a plurality of data lines (220), and a common voltage circuit (205) configured to generate a common voltage signal. Each pixel unit includes a pixel electrode (242), a common electrode (243), and a coupling member (245). The coupling member is connected between the pixel electrode and a corresponding one of the data lines, and is configured to transfer an electrical potential shift of the corresponding common electrode to the corresponding data line when one of the data voltage signals is applied to the pixel electrode. The common voltage circuit is configured to compensate the common voltage signal according to a feedback signal obtained from the data lines.