238results about How to "Control brightness" patented technology

A driving method and apparatus for a liquid crystal display are disclosed that stabilizes the variation of the brightness of a back light in correspondence with data to be displayed. In the method, the data is converted into brightness components. The brightness components are divided into a plurality of brightness areas. The brightness components are arranged into a histogram for each frame and thereafter a control value of a most-frequent value or average value of the histogram is extracted. The extracted control value is stored along with other control values including the extracted control value of a frame prior to the control value of the current frame by at least two frames. The brightness of the back light is controlled using the extracted control value of the current frame and one or more of the other stored control values.

An apparatus and method for driving a light source of a liquid crystal display device are provided. The apparatus includes a liquid crystal display panel, a backlight unit including a plurality of light emitting diodes (LEDs) to irradiating light to the liquid crystal display panel, and a driver to selectively drive the LEDs and selectively control a brightness of light generated by the LEDs.

A liquid crystal display and control method thereof, having a liquid crystal display panel, a light emitting diode device which is disposed on the rear of the liquid crystal display panel and which is divided into a plurality of partitioned areas that are capable of being driven independently, a light guide part disposed for each of the partitioned areas, an image calculating part for dividing the liquid crystal display panel into a plurality of regions and calculating the brightness of each region by using image data, and an inverter and an inverter controller to provide differentiated power to the partitioned areas based on the calculated brightness.

The invention provides an intelligent dimming module and an intelligent dimming LED lamp and a control method thereof, and relates to the field of LED electronic circuits. The intelligent dimming module comprises a power supply conversion module, a Zigbee control module, a PWM control module and an intelligent dimming module. The power supply conversion module is connected with a power supply, and is connected with the Zigbee control module and the PWM control module; the intelligent dimming module is connected with the Zigbee control module, the Zigbee control module is connected with the PWM control module, the PWM control module is connected with an LED lamp, the intelligent dimming module receives an input signal of a user and outputs a corresponding control signal, and the control signal is transmitted to the PWM control module through the Zigbee control module and is used for controlling working of the LED lamp. The brightness of the LED lamp is adjusted optionally in all-color range; and the intelligent dimming LED lamp is matched with an intelligent household system and can be applied to various scenes.

The invention provides a liquid crystal display device which has blue phase liquid crystal. The liquid crystal display device comprises a plurality of electrodes. In the invention, at least one pair of electrodes is arranged on one side of the blue phase liquid crystal to supply a transverse electric field to drive the macromolecular stabilized positive type blue phase liquid crystal for increasing the penetration rate of the light and controlling the bright state of the liquid crystal display device; and at least one pair of electrodes are arranged on the opposite sides of the blue phase crystal liquid to supply a vertical electric field, so the macromolecular stabilized positive type blue phase liquid crystal has excellent optical isotropy in a dark state and light leak in the dark state is reduced.

The invention relates to an organic electroluminescent device. The organic electroluminescent device comprises a hole injection layer (6), a hole transmission layer (5), a luminescent layer (4), an electronic transmission layer (3), an electronic injection layer (2) and a cathode layer (1) which are connected sequentially from one side of an anode layer (7), wherein the luminescent layer is a perovskite type quantum dot; the perovskite type quantum dot is CsPbXaYb; and X comprises any one of Cl, Br or I, Y comprises any one of Cl, Br or I, X and Y are different, a is more than 0, b is more than 0, and a plus b is equal to 3. The organic electroluminescent device can regulate and control the luminescent property by controlling the proportion of luminescent layer perovskite type quantum dot halogen, and is high in brightness, small in starting voltage and simple in preparation process.

The invention discloses an LED (light emitting diode) illumination driving circuit and a method. The LDE driving circuit comprises an energy transfer element, a switching tube, a driver and a feedback circuit, wherein the energy transfer component is used to receive and transfer electric energy; the switching tube is coupled with the energy transfer component and turns on or turns off based on the driving signal output by the driver; the driver is coupled with the feedback circuit and outputs the driving signal; the feedback circuit is coupled with the output end of the energy transfer component and outputs feedback signal to the driver; and the feedback circuit comprises a sampling circuit and a current sharing circuit. Therefore, the LED driving circuit has the advantages of over voltage protection and precise current sharing.

The invention discloses an intelligent dimming controller in an LED shadowless lamp lighting system. A blurred visual image processing technology is adopted to conduct feature analysis and processing on images in a surgical view field, brightness information and chrominance information of a lighting environment are extracted, and current control parameters of LED light sources are calculated through an intelligent processing algorithm. Specifically, the images in the surgical view field are converted into digital image signals firstly, the signals are read into the system through a video image collecting module, then the signals are analyzed through an image analysis and processing module, illuminance distribution information and chrominance distribution information are extracted, corresponding illuminance feature vectors and corresponding chrominance feature vectors are extracted through an illuminance and chrominance feature extraction module, a shadow area generated by a shielding object is split through a blurred image dividing module, the driving current value of the corresponding LED light source is worked out through a blurred neural network, the driving current value is sent to an LED controller to adjust the brightness of a corresponding LED. Thus, the purposes of shadow eliminating, illuminance evening and constant-light control are achieved, automatic dimming control is realized, no manual intervention is needed, and shadows are completely eliminated.

A brightness adjusting circuit for an LED lamp has a compensating circuit, a bridge rectifier, a filter capacitor and a current limiting circuit. The compensating circuit is connected between an output terminal of a light regulator and an AC wire to output a regulated input voltage. The bridge rectifier is connected to the compensating circuit and converts the regulated input voltage to a DC voltage. The filter capacitor is connected to the bridge rectifier. The current limiting resistor is connected between the bridge rectifier and the LED lamp to limit a current flowing through the LED lamp. When the light regulator is adjusted, the regulated input voltage across is changed accordingly. Therefore, the DC voltage produced by the bridge rectifier is varied to regulate the brightness of the LED lamp.

The provided FPGA-based video image processor comprises: a balance module to receive and compensate signal of HD / SD format to send processed signal into next module, a deserializer module to convert serial data into 10bit / 20bit parallel data, a drive module, a serializer module to convert parallel data into serial data, a clock module to provide 1.485GHz clock signal, and a FPGA control processor. This invention can real-time process signal of HD / SD format conveniently, can custom different IP kernels to upgrade hardware easily for future requirement, and has high performance-to-price rate.

The display device of the invention comprises a plurality of scanning lines (Wscan and Escan) which are selected successively, a plurality of data lines (Data) to which the writing electric current (Idata) in accordance with brightness information is supplied according to the scanning line selection, and a plurality of pixels (PX) arranged at intersecting points between the scanning lines and the data lines. Each of the pixels comprises a light emitting element (OLED), a driving transistor (TFT4), a capacitor (C) connected to the gate (Nd) of the driving transistor for accumulating writing data, a first transistor (TFT1) which is turned on during writing period in which the scanning lines are scanned and which connects the data lines and the drain of the driving transistor, and a second transistor (TFT2) which is turned on during the writing period and which short-circuits the gate and drain of the driving transistor. With such a structure, the light emitting element can be driven with a driving electric current equivalent to the writing electric current, irrespective of variations in characteristics of the transistors,

The present invention provides a LED driver for controlling the brightness of the LED. An inductor and a switch are connected in series with the LED for controlling the current of the LED. A diode is coupled in parallel to the inductor for freewheeling the energy of the inductor through the LED. A control circuit is developed to generate a control signal for switching the switch in response a reflected signal of inductor and the LED current. The LED current is further adjusted in response to the reflected signal. The value of the reflected signal is correlated to the LED temperature. Therefore the LED current can be programmed in accordance with the LED temperature.

An electron emission device for controlling brightness by converting a brightness level of input video signals. The electron emission device calculates brightness levels of video data which indicate a brightness degree for each of the images corresponding to the video signals, compares the brightness levels with a reference brightness level stored in a lookup table, calculates a conversion index of the input video signals, converts the video data stored in a memory according to the calculated conversion index, and displays the images based on the converted video data.

In one embodiment, the present disclosure provides a method to control the brightness of a display. One exemplary method includes generating a signal indicative of a display brightness level, and controlling the brightness of the display, based at least in part on the signal indicative of a display brightness level.

This invention provides a projector capable of correctly informing a user of replacement time of a lamp and significantly improving performance and operation reliability. A storage circuit is mounted in a detachable lamp unit for accommodating a lamp, and information on the lamp and so on are stored in the storage circuit. If the switch of a projector proper is turned on, a main circuit reads lamp operating time up to the last time from the storage circuit, and compares the read operating time to replacement time of the lamp stored in advance so that the light is emitted from the lamp if the operating time is less, and display for prompting the lamp replacement is performed if the operating time is more, and the light is emitted from the lamp thereafter. If the switch of the projector proper is turned off, the main circuit adds the operating time of this time to the operating time of the lamp up to the last time read from the storage circuit on turning on the switch and writes it to the storage circuit.

The invention provides a breath light control circuit, comprising a power supply, a first resistance and a second resistance which are connected in series, a first switching tube, a second switching tube, a third resistance, a fourth resistance and a controller, wherein one end of the first resistance is connected with the power supply, the collector of the first switching tube is connected with one end of the second resistance, and the emitter of the first switching tube is grounded; the base of the second switching tube is connected with a node between the first resistance and the second resistance, the emitter of the second switching tube is connected with the power supply; one end of the third resistance is connected with the collector of the second switching tube, the other end of the third resistance is connected with a breath light; one end of the fourth resistance is connected with the base of the first switching tube; and the controller is connected with the other end of the fourth resistance and is used for applying a PWM control signal to the first switching tube by virtue of the fourth resistance and gradually adjusting duty ratio of the PWM control signal according to a preset step size by taking a preset time as a period. The breath light control circuit provided by the invention has the advantages of simple design and low cost.

The present invention is back light system and its control method. The brightness signal of the light emitting module in the back light system is compared with preset brightness signal, and is regulated based on the comparison result to make the brightness signal of the light emitting module equal to the preset brightness signal. Where, the preset brightness signal changes with the temperature of the light emitting module to limit the back light brightness and the chroma within some stable range.

An LCD device includes a timing control circuit having a flicker reducing portion for detecting flickers in the entire one frame to be displayed in a liquid crystal panel and controlling a brightness of the backlight according to an amount of detected flickers. The timing control circuit can evidently reduce visually recognized flickers by dimming the brightness of the backlight when the detected flickers is more than given rate.

A backlight control circuit includes a shift register, first and second dividers, a counter / decoder, data registers and control signal generators. The shift register stores digital video data based on a transmission clock signal. The first and second dividers divide the transmission clock signal to generate first and second clock signals, respectively. The counter / decoder counts a number of pulses of the first clock signal and outputs a decoding signal. The decoding signal is used to set an output timing of the digital video data stored in the shift register. The data registers receive and store the digital video data stored in the shift register based on the decoding signal. The control signal generators generate brightness control signals based on the second clock signal in response to the digital video data stored in the data registers to locally control a brightness of light sources of a plurality of light sources.

An electronic mobile device with a display may include brightness controls that may be adjusted upon detection in change of orientation of the device. An orientation sensor may be coupled to a processor. The processor, in response to a change in orientation, may determine if the device is oriented such that an ambient light sensor may be rotated. Ambient light sensitivity levels may be adjusted to account for the position of the ambient light sensor in a rotated orientation.

The invention provides a backlight unit, a control method thereof and a liquid crystal display device. The control method comprises the following steps: acquiring backlight data corresponding to eachpartition, the backlight data comprising data of a plurality of bits; the light-emitting unit of each partition is segmented into a plurality of sub-fields with different time lengths in the light-emitting process of one frame, each sub-field corresponds to data of one bit, and any two sub-fields comprise different numbers of secondary sub-fields; and outputting the plurality of sub-fields according to a preset sequence. According to the backlight unit, the brightness of the backlight is adjusted by segmenting and partitioning the sub-fields so as to reduce the power consumption of the backlight unit, and any two sub-fields comprise different numbers of secondary sub-fields so as to increase the charging times of the light-emitting unit of each partition in each sub-field, so that the brightness of each partition of the backlight unit is more accurately controlled, and the phenomenon of uneven brightness is eliminated.

The invention discloses a multifunctional industrial scanner. The multifunctional industrial scanner comprises a carrier platform for accommodating an object to be scanned, a vertical column arranged on the carrier platform and a camera assembly; the industrial scanner further comprises a height regulating system; the height regulating system comprises a guide rail and a lifting motor mounted on the guide rail; the guide rail is mounted on the vertical column; the camera assembly is mounted on the guide rail, and is driven by the lifting motor to move up and down along the guide rail; the multifunctional industrial scanner further comprises light source compensation systems and a light source and power source control system, and adopts the rolling-type carrier platform. According to the multifunctional industrial scanner, the height regulating system is used for detecting height and realizing automatic scanning height regulation; the light source compensation systems are used for light source compensation; through the light source and power source control system, the light source brightness regulation and work signal receiving can be realized, so that clear and bright light during shooting is ensured, and the optimal scanning effect is realized.

The invention discloses an LED intelligent street lamp control system and method for urban road illumination, and belongs to the field of LED intelligent street lamps. The control system comprises a central control room, a smart lamp post, a time sequence generator, a moving object detector, a brightness controller, an air visibility monitor and an AC / DC power supply. The control method comprisesthe following steps that: S1: 24 hours each day are divided into two street lamp working basic time periods to be respectively controlled through the time sequence generator, wherein the first time period is from night 19:00 to a next morning 07:00, and the second period is from the morning 07:00 to 19:00; and S2: setting the first period as the 'LED street lamp lighting period under normal condition'. The LED intelligent street lamp control system and method can adjust the state of the LED street lamp in due time according to the ambient weather condition, and can achieve intelligent control.

In a road measurement device, a calibration unit (48) generates a formation parameter used for formation of a scale image from a result of picking-up a calibration figure for calibration by an image pick-up means (10). An image acquisition unit (44) acquires a road image at every predetermined running distance from the image pick-up means (10). In this event, a coordinate information acquisition unit (56) relates coordinate information acquired from a coordinate acquisition device (12) to the road information. An image pick-up height and angle acquisition unit (46) acquires from an image height and angle measurement unit (11) a height from the road surface and an angle defined between an image pick-up direction and a direction in parallel with the road plane when the image pick-up means (10) picks up the road image. A scale formation unit (50) selects the formation parameter in accordance with the height and the angle, at which the image pick-up direction is parallel to with the road surface, acquired by the image pick-up height and angle acquisition unit (46), and generates a scale image based on the formation parameter.

A blinking backlight device and an operation method thereof are provided. The blinking backlight device comprises a light source brightness balance module, a blinking control module and a storage unit. An image detection unit of the blinking control module is used for comparing a recent frame data and a frame data read from the storage unit. When the recent frame data comprises a motion image, the blinking backlight is enabled. When the recent frame data comprises a static image, the blinking backlight is disabled. In addition, the light source brightness balance module is used to control the brightness and the duty cycle of the cold cathode fluorescence lamp according to whether the frame data comprises the motion image or the static image.

Disclosed are an LED lighting apparatus and a control circuit thereof which controls the brightness of a lamp including LEDs using a dimmer. The LED lighting apparatus and the control circuit use a starting current based on a rectified voltage, in order to supply a holding current to the dimmer in a state where a lamp including LEDs is turned off.

The invention discloses a driving method and circuit of an intelligent control lighting appliance. Intelligent control of a lamp fixture is driven without using a driving IC chip, driving signals are directly output through the I / O port of a single-chip microcomputer for adjusting the conduction time of MOS tubes of voltage reduction circuits so as to realize control of current or voltage of a load, accordingly, the color temperature and the brightness of the lamp fixture are controlled, the adjustment precision is high, feedback signals are adjusted and fed back also through the single-chip microcomputer so as to realize stable output at a load end, the color temperature and the brightness of the lamp fixture can also be adjusted through a wireless control scheme, the circuit is simple, the cost is low, the size is small, the installation is convenient, and the application prospect is good.

With the LED driving circuit of the present invention, even if the input voltage is higher than the output voltage, the brightness of the LED can be controlled to be constant. If the input voltage Vin is higher than the output voltage Vout due to the difference in the threshold voltage Vf of the LED (21), and the LED drive circuit cannot perform the step-up operation, the operation of the LED drive circuit is switched from a step-up switching regulator to a voltage regulator. action, therefore, the LED drive circuit can operate normally.

The invention relates to an intelligent lighting control management system which comprises a main control module, an input module and a lighting control module. The input module, the lighting control module and the main control module are connected through a controller area network (Can) Bus. The lighting control module is connected with a lighting lamp. The system further comprises a sensor module. The sensor module is connected with the main control module through the Can Bus. The lighting control module controls brightness of the lighting lamp through pulse width modulation (PWM). According to the intelligent lighting control management system, lighting time and the brightness of a lighting source can be controlled according to different application scenes, different light rays are created according to the different scenes, intelligent management and simplified operation can be achieved and change of layout and a control mode of a further lighting system is facilitated.