39results about How to "Precise dimming" patented technology

The invention provides a dimmable LED (Light-Emitting Diode) driving circuit and a driving method. An input current in a first power-level circuit is controlled as a square wave signal within a rectifier conducting time interval by an input current control circuit, the peak value of the input current is a constant value and meets the requirement of the minimum load current of an electronic transformer, and the valley value of the input current is zero; and the input current is kept at zero within a rectifier nonconducting time interval. The load current of the electronic transformer can be kept larger than the minimum load current, and thus, a normal working state can be kept in the working process, and the problem of LED load flicker caused by the switching off of the electronic transformer is avoided; in addition, information on the input current is detected through a dimmable signal generating circuit so that a dimmable signal for representing information on a conduction angle of a rectifier is obtained, an LED load is precisely dimmed, the dimming range is wide, and the dimming effect is good; and finally, constant-current control for the current of the LED load is realized by an output current control circuit, and therefore, the brightness stability of the LED load is ensured.

The invention relates to an LED (Light Emitting Diode) illumination intelligent control system which comprises a synchronous rectification unit used for providing direct-current power for at least two intelligent power control units, wherein the output end of each intelligent power control unit is connected with a corresponding LED light group unit via an electric wire; and the synchronous rectification unit is connected with each intelligent power control unit by a high-voltage direct-current bus. In the intelligent control system, stable constant-voltage direct current is provided for an LED illumination system by the synchronous rectification unit, so that the whole illumination system can operate under high power factor with less harmonic wave. the corresponding LED light group units are dynamically and precisely dimmed by the intelligent power control units, and the LED operation situation is detected in real time and communication with an external control center is carried out. The intelligent control system has the characteristic of reasonable structure, and is convenient to control, the working environment temperature of an LED light group can be improved, and the reliability and the service life of an LED illumination light can be improved.

The invention discloses a digital linear dimming method for a high-power LED and belongs to the technical field of dimming methods. The digital linear dimming method for the high-power LED is characterized by comprising the following steps that firstly, a single-chip microcomputer receives a potentiometer signal, a current signal, a voltage signal and an LED temperature signal and conducts analog-to-digital conversion; secondly, based on the current signal, the voltage signal and the temperature signal, a luminance compensation coefficient A is calculated; thirdly, a lumen value L is calculated, and an output luminance value Lch which is generated after temperature compensation is calculated according to the luminance compensation coefficient A; fourthly, the current Io which needs to be supplied is obtained according to the Lch; fifthly, whether a sampled current signal is equal to the Io or not is judged, if yes, a result is output to a PWM control circuit, and if not, the result is adjusted and then output to the PWM control circuit. The digital linear dimming method for the high-power LED is convenient to operate, accurate in dimming, and suitable for dimming of the high-power LED.

The invention discloses a large power LED digital linear light modulation system and belongs to the technical field of an LED light modulation system. The large power LED digital linear light modulation system is technically characterized by comprising a filter and protection circuit, a PWM control circuit and an output filter circuit which are sequentially in circuit connection between a DC power source and an LED light source, wherein the PWM control circuit is in circuit connection with a single-chip microcomputer, the single-chip microcomputer is in circuit connection with a linear potentiometer, a current sampling amplification circuit is arranged between the output filter circuit and the LED light source, the current sampling amplification circuit is connected with the single-chip microcomputer, a welding point side edge of the LED light source is provided with a temperature sensor, and the temperature sensor is connected with the single-chip microcomputer through an ADC analog-to-digital converter. The large power LED digital linear light modulation system aims to have properties of compact structure and accurate light modulation and can be used for light modulation of a large power LED.

There is provided a method and corresponding lighting device (100), and a receiver, which employs code modulation which provides a compatibility of code modulation in a dimmable lighting system. The lighting device comprises means for dimming the output light (102), which employs multiple dimming modes, each representing dimming the light output from lighting device by means of a respective dimming method, and means for embedding a code in the light output (103). The means for embedding a code in the light output employs code modulation which is based on controlling the instantaneous dimmed light output from the lighting device such that the integrated value of the dimmed light output during a time period T is modulated to embed the code. The code may then subsequently be extracted from the modulated light by means of an integrate-and-dump process at a receiver, without knowledge of the dimming method and/or dimming level of the lighting device.

The invention discloses an intelligent multifunctional desk. The intelligent multifunctional desk comprises a fixed desktop, a movable desktop, an adjustable desk leg, an intelligent circuit board, and a control panel, wherein the fixed desktop is arranged at the periphery of the movable desktop and connected with the movable desktop in a pivotal mode, the fixed desktop is also fixedly connected with the adjustable desk leg, the intelligent circuit board is encapsulated at one corner of the fixed desktop and electrically connected with the control panel, the movable desktop, and the adjustabledesk leg, and the control panel is movably connected with one side wall of the movable desktop. According to the intelligent multifunctional desk, the movable desktop with adjustable angle and the adjustable desk leg with adjustable height are arranged, during using by a user, the adjustment of the height of a desk and the adjustment of the angle of a desktop can be realized through the control panel in cooperation with the intelligent circuit board encapsulated in the fixed desktop, and using needs of the user in different states are more easily met .

The invention relates to a music signal controlled PWM dimming and color modulating LED lamp, which comprises a music signal acquisition module, a signal processing module, a mobile phone APP module, a bluetooth communication module, a digital-to-analog converter, a PWM control module and an LED lamp, and is characterized in that the LED lamp is an RGB LED lamp, the mobile phone APP module is wirelessly connected with the bluetooth communication module, the bluetooth communication module is connected with the digital-to-analog converter, the digital-to-analog converter is connected with the PWM control module, the PWM control module is connected with the LED lamp, and the PWM control module adjusts the color and brightness of the LED lamp through changing the duty ratio of the LED lamp. The corresponding duty ratio of required LED light can be directly calculated in an inverted way through inputting a corresponding parameter according to an algorithm chip and circuit, and dynamic adjustment is performed on the color and illumination under the condition of adjusting the duty ratio. PWM dimming has the advantages that the dimming is more accurate, the color changes faster, the dimming color is brighter, and the dimming mode has more color changes than the traditional mode. Meanwhile, the lamp is low in heat generation, and the efficiency is higher.

An image shooting device includes an image shooting component, a brightness detector, a flash component, a shift detector, a controller, and a flash amount determining component. The shift detector detects a shift amount of a subject position in a set of image data that has arisen due to shaking of the image shooting device. The controller corrects, on the basis of the detected shift amount, at least one of two sets of image data acquired within non-flash state and flash-emitting state, such that positions of a detection target region with respect to the subject position of the respective sets of image data are substantially matched. The flash amount determining component determines a flash amount of the flash component on the basis of the detected brightness level.

The invention discloses an electronic ballast for a fluorescent lamp, which comprises a half-bridge inverter circuit module with an inductor, a singlechip control circuit module, and is also provided with a preheat circuit module and a built-in dimming circuit module, wherein the preheat circuit module is a bidirectional silicon-controlled circuit module controlled by a triode type opto-coupler, a control signal of the preheat circuit module is from the singlechip control circuit module, and a power supply is from the secondary side of the inductor; and the dimming circuit module is an unidirectional silicon-controlled dimming circuit module, a control signal of the dimming circuit module is from the singlechip control circuit module, a power supply of the dimming circuit module is from a 5V power supply of the singlechip control circuit module, and the dimming circuit is used for controlling a ground terminal of the basic half-bridge inverter circuit module. The electronic ballast can adjust the preheating of a fluorescent light tube correspondingly, prolong the service life of the fluorescent light tube, simultaneously shorten the conversion process time of the fluorescent lamp after the preheating is completed, ensure that damages to a light tube when the fluorescent lamp is turned on each time are reduced to minimum, accurately control dimming and has a simple structure.

A projector includes a lamp, a ballast, an aperture member including light-blocking plates, a light-blocking plate driving motor, a control section, a light modulation device, and a projection optical system, and the control section controls the ballast and the light-blocking plate driving motor so as to modulate the lamp power based on a luminance of the video signal while fixing the aperture of the aperture member to a constant value in a picture period in accordance with a luminance parameter corresponding to a video signal group in the picture period among a series of the video signals.

An APP music intelligent lamp capable of light adjustment and toning comprises a mobile phone APP module, a Bluetooth communication module, a digital-to-analog converter, a PWM control module and a LED lamp, the LED lamp is a RGB LED lamp, the mobile phone APP module is in wireless connection with the Bluetooth communication module, the Bluetooth communication module is connected with the digital-to-analog converter, the digital-to-analog converter is connected with the PWM control module, the PWM control module is connected with the LED lamp, the Bluetooth communication module employs the Bluetooth frequency hopping algorithm and the mobile phone APP module to perform data transmission, the Bluetooth frequency hopping algorithm writes in the mobile phone APP and the Bluetooth communication module, and the PWM control module adjusts the color and the brightness of the LED lamp through changing of the duty ratio of the LED lamp. The APP music intelligent lamp capable of light adjustment and toning can directly perform back-calculation of a corresponding duty ratio of a required LED light through inputting corresponding parameters through the algorithm chip and circuit and perform dynamic adjusting of the color and the illumination in the condition of adjusting the duty ratio, the PWM light adjustment is more accurate in light adjustment, faster in color changing, more beautiful in color of light adjustment and more color changing in the light adjustment mode compared to a traditional mode.

The invention discloses a drive circuit of a light emitting diode, in particular to a drive circuit of the light emitting diode, which can be accurately controlled and accurately dim light. The drive circuit mainly comprises a voltage source for proving working voltage, at least one drive module, at least one light emitting diode and a programmable controller, wherein each drive module comprises a switch circuit and a current and voltage detector respectively. The drive circuit utilizes the programmable controller to connect the switch circuit and the current and voltage detector of each drive module, can adjust a switch state of the switch circuit according to a current signal or a voltage signal of the current and voltage detector and respectively and accurately control current passing through each light emitting diode or voltage applied to each light emitting diode.

The invention discloses an automobile headlamp dimming device and a control method. The automobile headlamp dimming device comprises a shell (1) and a shell cover (2), and the shell cover (2) is connected to an opening of the shell (1); the device is characterized in that a stepping motor (3) is arranged in the shell (1), and a ball head assembly is arranged on the shell (1); a screw rod (301) is arranged on an output shaft of the stepping motor (3), the ball head assembly comprises a driving gear (6), and the screw rod (301) is meshed with the driving gear (6); the stepping motor (3) is started, under the action of the screw rod (301) and the driving gear (6), the stepping motor (3) can drive the ball head of the ball head assembly to move, and therefore the angle of the automobile headlamp is adjusted. According to the automobile headlamp dimming device and the control method, the structure is simple, intelligent control can be achieved, and gear adjustment is more refined.

An APP intelligent lamp capable of light adjustment and toning comprises a mobile phone APP module, a Bluetooth communication module, a digital-to-analog converter, a PWM control module and a LED lamp, the LED lamp is a RGB LED lamp, the mobile phone APP module is in wireless connection with the Bluetooth communication module, the Bluetooth communication module is connected with the digital-to-analog converter, the digital-to-analog converter is connected with the PWM control module, the PWM control module is connected with the LED lamp, the Bluetooth communication module employs the Bluetooth frequency hopping algorithm and the mobile phone APP module to perform data transmission, the Bluetooth frequency hopping algorithm writes in the mobile phone APP and the Bluetooth communication module, and the PWM control module adjusts the color and the brightness of the LED lamp through changing of the duty ratio of the LED lamp. The APP intelligent lamp capable of light adjustment and toning can directly perform back-calculation of a corresponding duty ratio of a required LED light through inputting corresponding parameters through the algorithm chip and circuit and perform dynamic adjusting of the color and the illumination in the condition of adjusting the duty ratio, the PWM light adjustment is more accurate in light adjustment, faster in color changing, more beautiful in color of light adjustment and more color changing in the light adjustment mode compared to a traditional mode.

The invention provides an electric dimming venetian blind device which includes a U-shaped top groove, venetian blind sheets, a vertical bottom bar, a driving device and a lifting device. The drivingdevice includes a tubular motor and a driving rotating wheel, the lifting device includes a coil tube, a rope winding device, a ladder rope and a lifting rope, the tubular motor is located in the coiltube, the driving rotating wheel is connected to an output shaft of the tubular motor, the driving rotating wheel is coaxially and fixedly connected with the coil tube, the coil tube is placed in theU-shaped top groove, and the two ends of the coil tube are connected to the two ends of the U-shaped top groove through stainless steel rotating wheels; the rope winding device is fixed on the coil tube, the upper end of the ladder rope is fixed to the rope winding device, and the lower end of the ladder rope is connected to the venetian blind sheets in sequence to be fixedly connected with the vertical bottom bar; and the upper end of the lifting rope is fixed to the rope winding device, and the lower end of the lifting rope sequentially penetrates through limiting holes in the venetian blind sheets to be fixedly connected with the vertical bottom bar. The electric dimming venetian blind device has the beneficial effects that a venetian blind can be freely lifted and the dimming functioncan be realized, the noise is small, and natural silent dimming can be realized without notice.

The invention relates to an AC phase-cut digital dimming control device and control method. The device comprises a zero-crossing detection circuit, an MCU main control circuit, a drive circuit, and a phase-cut dimming circuit, wherein the MCU main control circuit is used for receiving a zero-crossing signal detected by the zero-crossing detection circuit, and outputting a zero-crossing compensation control signal according to the zero-crossing signal, the driving circuit is used for receiving the zero-crossing compensation control signal output by the MCU main control circuit, performing level amplitude conversion on the zero-crossing compensation control signal and outputting an MOS/IGBT driving level signal, and the phase-cut dimming circuit is used for receiving the MOS/IGBT driving level signal output by the driving circuit and outputting a phase-cut control signal to a lamp to be dimmed according to the MOS/IGBT driving level signal so as to perform phase-cut dimming on the lamp to be dimmed. According to the invention, the phase-cut control signal is output to the lamp to be dimmed in the next period so as to carry out phase-cut dimming on the lamp to be dimmed, so that accurate dimming can be realized, and the phase-cut dimming accuracy is further improved.