101results about How to "Wide dimming range" 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 a high-power LED intelligent control system which includes a MCU center controller, a constant current drive circuit, a high power LED array, an optical detector, a temperature sensor, a memorizer and a wireless communication module. The system regards the MCU center controller as a core, the constant current drive circuit is controlled by the controller for adjusting the output current size, correspondingly, adjusting high power LED brightness; the optical detector, the temperature sensor, the memorizer and the wireless communication module also connect with the center controller. The system provided by the invention can intelligent control LED lamp input current size, make the LED chip junction temperature lower than threshold that can increase LED lamp working life, and record LED lamp working parameter convenient to follow detection timely, and detect LED lamp fault with low cost. The system has advantages of high efficiency, flexible, intelligent and energy saving. One important characteristic of the system is that the system can wireless remote control LED road lamp or channel lamp, realize downloading key LED working parameter timely, is convenient for managing the LED lighting system, reduce operating cost for managing the LED lighting system, and also embody advantage of the LED lighting with high efficiency and energy saving.

The application discloses an LED (light-emitting diode) dimming driving circuit which comprises a dimmer, a rectification circuit, a transformer, a control circuit and a power switching tube, wherein the control circuit is used for converting obtained voltage signals reflecting rectified voltage to direct current electric signals which are in direct proportion to the dimming angle, controlling the on-time and the off-time of the power switching tube according to the direct current electric signals, rectified voltage sampled signals and rectified voltage peak value sampled signals and enabling the output current of the LED dimming driving circuit to change along with the change in the dimming angle; furthermore, the output current can be kept constant under the same dimming angle; and simultaneously, the range of average output current of the LED dimming driving circuit is larger and the dimming range of the LED dimming driving circuit is further wider.

The invention relates to a light-dimmer driving circuit. The light-dimmer driving circuit comprises a power supply input module, a transformer, a current output driving module, a pulse width modulation (PWM) module, an input voltage sampling module, an output voltage sampling module and a control center, wherein the power supply input module is mainly used for rectification and filtering of an input voltage signal, the transformer is used for voltage reduction of the voltage signal output by the power supply input module, the current output driving module is used for driving of current output according to the voltage signal which is transformed, the PWM module is used for adjusting output power of the current output driving module according to a control signal in the control center, the input voltage sampling module is used for sampling of the input voltage signal and transmitting the input voltage signal to the control center, the output voltage sampling module is used for sampling of output voltage and transmitting the output voltage to the control center, and the control center is used for controlling a PWM signal according to an input voltage sampling signal, an output voltage sampling signal and an input current signal. According to the light-dimmer driving circuit, due to the fact that the control center is used for controlling the PWM signal according to the input voltage sampling signal, the output voltage sampling signal and the input current signal, the output power of the current output driving module is enabled to change evenly, flicker-free light adjusting is achieved, constant current output is achieved, and range of the light adjusting is wide.

The invention discloses an electrochromic material which is a porous film compounded through nickel oxide and 3, 4-ethylene dioxygen thiofuran, wherein the composite film has a random porous structure; the range of aperture is between 10 and 250 nm; and the thickness of the film is between 200 and 500 nm. The preparation method comprises the following steps: 3, 4- ethylene dioxygen thiofuran is used as a monomer; the porous nickel oxide is used as a conductive template; lithium perchlorate is added into an acetonitrile solution and is used as a supporting electrolyte to prepare the nickel oxide / poly3, 4-ethylene dioxygen thiofuran composite porous electrochromic film through an electrochemical cyclic voltammetry sedimentation method. The prepared electrochromic material has good mechanical performance and electrochromic performance, shows multiple electrochromism and rapid discoloring effect, can be assembled to a transmission-type or reflection-type full solid electrochromic device, and has wide application prospect in information storage recording, architectural glass smart window, large screen display, infrared stealth and other fields.

A projection display uses a light modulating device to modulate, in accordance with image data, light radiated from a light source, project the modulated light onto a screen, and display an image. The projection display separates a unit of time configuring the image data into an effective light time when the light modulating device can express the light as an image on the screen and an ineffective light time when the light modulating device cannot express the light as an image on the screen. The projection display increases the power supplied to the light source during the effective light time over the power supplied to the light source during the ineffective light time.

The invention belongs to the field of LED control, and mainly discloses a linear constant-current circuit for light modulation of a silicon controlled rectifier. Three sets of linear constant-current modules are combined with two sets of LED lamp strings. Furthermore current adjusting resistors with different resistances are arranged according to the positions of the three sets of linear constant-current modules in a circuit, thereby adaptively parallelly connecting or serially connecting the two sets of LED lamp strings according to the magnitude of the input voltage. The linear constant-current circuit has advantages of effectively improving utilization rate of the LED lamp strings, increasing light modulation range of the silicon controlled rectifier, ensuring high operation efficiency of the circuit and reducing circuit loss.

A solid-state lighting system includes a light-emitting device connected in series with a variable dim setting resistor, an adjustable regulator, and a current sensor disposed in a feedback loop between an adjust input of the adjustable regulator and the variable dim setting resistor. The voltage dropped across the variable dim setting resistor is forced to remain constant irrespective of the resistance setting of the dim setting resistor. The current sensor measures or senses the current flowing through the variable dim setting resistor and causes the adjustable regulator to adjust its output voltage and the forward voltage drop across the light-emitting device so that the current flowing through the light-emitting device matches the current set by the variable dim setting resistor. Controlling the current in this manner allows dimming to be performed over an extremely wide dimming range, to very low light levels, and without producing light flicker at any dim level.

The present invention discloses an HUD brightness automatic regulation device and method in the automatic control technology field. The device comprises: a horizontal light sensor and a vertical light sensor, wherein the installation directions of the horizontal light sensor and the vertical light sensor are mutually perpendicular and the measuring ranges of the horizontal light sensor and the vertical light sensor are the same, and the vertical light sensor is provided with a light filter membrane; a microprocessor, wherein the microprocessor comprises an A / D processing module, a data processing module and a PWM module, the horizontal light sensor and the vertical light sensor are configured to convert the detected light brightness signals to digital signals through the A / D processing module and then transmit the digital signals to the data processing module, and the data processing module performs processing and calculation to obtain PWM digital quantity applied to the PWM module; the LED module, wherein the LED module comprises a LED driver and a LED lighting chain, and the PWM module controls the brightness of the LED lighting chain through the LED driver; an external rotary knob configured to transmit the brightness regulation signals to the A / D module for manual regulation of the brightness. The light regulation range is wide, and the light regulation is more smooth.

The invention provides an LED lamp bar drive circuit and a dimming method thereof, a backlight module and a display device, belongs to the technical field of display, and can solve the problem that existing PWM dimming can cause flickering or noise easily. The LED lamp bar drive circuit comprises a power supply unit for providing voltage for each branch of LED lamps, a current detection unit for detecting average value of total current input to LED lamp bars, and a control unit for controlling the LED lamps on each branch to be turned on / off according to the detection result of the current detection unit. The brightness of the LED lamp bars can be adjusted by controlling the on / off state of the lamps on the corresponding branch. The dimming method is high in efficiency, low in noise, and wider in dimming range. The LED lamp bar drive circuit is suitable for adjusting the brightness of various types of backlight modules.

The invention discloses a multi-way output LED constant-current driving circuit which comprises a power supply dimming module, a reverse activation control module, a current feedback module, a transformer, an output detection module and at least two LED load access channels. The invention further discloses a multi-way output LED constant-current driving method which is applied to the multi-way output LED constant-current driving circuit. The invention relates to the technical field of LED driving. By adopting the multi-way output LED constant-current driving circuit and the driving method, the reverse activation control module is combined with the power supply dimming module, the current feedback module, the output detection module and the transformer, constant driving current is output according to the number of LED lamps accessed through the LED load access channel and different dimming requirements, the operation is stable, and compared with the prior art of a constant-voltage driving power supply, the driving circuit needs no secondary constant current treatment and is low in cost. Tangent phase signals of the power supply dimming module are sampled in real time through the current control module, different current adjustment dimming ranges are output according to a tangent phase dimmer, and the purposes of low dimming depths and wide dimming ranges are achieved.

The invention discloses an auto-dimming spectacles and a manufacturing method thereof. The auto-dimming spectacles are characterized by being formed by stacking a photochromic layer, an anti-ultraviolet layer I, a substrate I, a transparent electrode layer I, a vertical alignment layer I, a dye liquid crystal layer, a vertical alignment layer II, a transparent electrode layer II, a substrate II and an anti-ultraviolet layer II sequentially from the front surface to a spectacles body, two or more spacing materials are arranged in the dye liquid crystal layer, planes of the substrate I and the substrate II are in matched fit with patterns on the transparent electrode layer I and the transparent electrode layer II, the substrate I, the substrate II, sealing mouths and sealing rings form a liquid crystal box, and the sealing mouths and the sealing rings are arranged around the dye liquid crystal layer. By optimized combination of photochromism and dye liquid crystals, dimming range of the auto-dimming spectacles is expanded; by processing of the liquid crystal layer different in thickness, continuous contract and brightness change under single voltage are realized; when the auto-dimming spectacles are worn in various environments with high light in daytime and with dark light in nighttime, visual experience is improved substantially.

The invention discloses a piezoelectric driving type variable-diaphragm dimming apparatus and method. The apparatus is composed of a variable diaphragm unit, a piezoelectric actuator and a pedestal. The piezoelectric actuator consists of four cantilever beams and eight piezoelectric ceramics; the four cantilever beams employ square ring beam structures formed by end-to-end connection of metallic elastic base bodies; driving feet in an interference fit relationship with the outer wall of a moving ring of the variable diaphragm unit are arranged at the midpoints of the inner wall of the four cantilever beams; and the eight piezoelectric ceramics are arranged on the outer wall of the two sides of the midpoints of the four cantilever beams correspondingly. When the apparatus works, excitation signals with a phase difference of 90 degrees are applied to the two piezoelectric ceramics on each beam, elliptic motion is caused at the driving feet, the moving ring is driven to make rotation, and thus a diaphragm piece is driven by the moving ring to rotate, so that expansion or contraction of the aperture of a through hole is realized. According to the invention, with piezoelectric driving, the piezoelectric driving type variable-diaphragm dimming apparatus has advantages of flat and compact structure, small size, light weight, high adjustment precision, fast speed, and high reliability; the performances of the optical instrument are improved; and the production cost is lowered.

The invention provides an LED driving circuit applicable to a silicon controlled rectifier light modulator, and a control circuit thereof. The control circuit comprises a light modulation phase detection circuit, a phase filtering circuit connected with the light modulation phase detection circuit, a non-linear reference circuit connected with the phase filtering circuit, a zero cross detection circuit in direct or indirect coupling with an output end of the LED driving circuit, an output current simulation circuit connected with the zero cross detection circuit, an average current ring adjusting circuit connected with the non-linear reference circuit and the output current simulation circuit, a reset circuit connected with the average current ring adjusting circuit, an interrupted time-delay circuit connected with the phase filtering circuit, and a main driving circuit connected with the reset circuit, the interrupted time-delay circuit and the zero cross detection circuit. The control circuit can realize high power factor single-stage light modulation and has advantages of no scintillation and good compatibility.

The invention discloses an LED driving circuit and a dimming control method thereof. The LED driving circuit comprises a rectifier bridge for converting an AC input voltage into a DC bus voltage having a half power frequency period; A main circuit connected between the first output terminal and the second output terminal of the rectifier bridge for supplying the load current required by the LED and adjusting the duration of the load current in the half power frequency period according to the DC bus voltage so as to realize dimming; And a drain circuit connected between the first output terminal and the second output terminal of the rectifier bridge for supplying a drain current, wherein the drain circuit controls on and off of the drain current according to the DC bus voltage and the loadcurrent, and the drain current is used for supplying a sustain current of the dimmer. The LED driving circuit adopts different modes to compensate the discharge current according to different conduction angles of the thyristor in the dimmer, thereby suppressing the flicker of the LED lamp, improving the compatibility of the LED driving circuit and the thyristor dimmer, and expanding the dimming range.

The invention relates to a lighting apparatus and an illuminating fixture with the same. A control circuit selects a first control mode in which a switching element is turned on and off so that a current flows through an inductor in a critical or discontinuous mode, thereby fully lighting a light source load. The control circuit selects one of a second control mode in which on time of the switching element is changed and a third control mode in which an oscillating frequency is changed according to an interval, to which a designated dimming ratio corresponds, to dim the light source load. An output capacitor connected between output terminals of a step-down chopper circuit smoothes pulsation component of an output current supplied to the light source load and has capacity set so that a ripple ratio of the output current is less than 0.5 at full lighting of the light source load.

A circuit structure and control method for controlling the light modulation of fluorescent lamp is disclosed. Said fluorescent lamp is driven by a semi-bridge resonant inverter type ballast working in constant frequency and constant duty ratio. Changing the DC input voltage of said ballast can modulate the light. Its variable DC power supply is taken from AC-DC converter for AC input power supply or DC-DC converter for DC input power supply.

The invention discloses fluorocarbon / palladium / magnesium-niobium pentoxide gas dimming film and a preparation method thereof. The fluorocarbon / palladium / magnesium-niobium pentoxide gas dimming film comprises a magnesium-niobium pentoxide composite film layer, a palladium catalytic layer and a fluorocarbon hydrophobic layer which are arranged sequentially on a substrate. The preparation method includes: growing the magnesium-niobium pentoxide composite film layer on the substrate, growing the palladium catalytic layer in situ on the magnesium-niobium pentoxide composite film layer, and depositing the fluorocarbon hydrophobic layer outside the fluorocarbon hydrophobic layer. Catalytic effect of palladium helps promote reversible conversion of hydrogen gas and hydrogen atoms in the hydrogen absorbing and hydrogen removal stages; niobium pentoxide is added to accelerate diffusion of hydrogen atoms in a magnesium substrate, magnesium hydroxide forms and decomposes faster, and the film can be repeatedly converted between a reflecting state and a transaprent state. The fluorocarbon film can effectively resist corrosion of inner film due to the external environment. The whole reaction process can be implemented at room temperature. The fluorocarbon / palladium / magnesium-niobium pentoxide gas dimming film has good weatherability, short response time, short recovery time and good process simplicity, and has important application prospect in the field of intelligent glass.

The invention provides a control circuit and a lighting device. The control circuit comprises a step-down circuit, a mean value calculation circuit, a light dimming interface circuit, an operational amplifier circuit, a logic circuit, a clock signal generator, a sampling unit and a detection unit. The mean value calculation circuit calculates an inductive current mean value based on the inductive current peak value and the inductive current conduction ratio. The operational amplifier circuit performs comparison based on the inductive current mean value and the inductive current reference value inputted by the light dimming interface circuit, and the comparison result acts as a first output signal to be outputted to the logic circuit. The logic circuit controls on / off of the first switch in the step-down circuit based on the first output signal and the clock signal inputted by the clock signal generator and adjusts the size of the inductive current by controlling the duty ratio of the first switch in the step-down circuit so as to adjust the current size of a load connected with the electric inductor. The control circuit is simple and convenient, and the lighting device provided with the control circuit has wide light dimming range and low cost.

The invention discloses a circuit and method for generating a self-adapting silicon-controlled light regulating signal. The circuit comprises a phase angle detection module, an inverter, a filter and a comparer. The circuit can generate a corresponding light regulating signal according to a conducting phase angle signal of an input signal. The circuit and the method disclosed by the invention have the advantages that: by the improvement of traditional silicon-controlled light regulating signal, the width of the light regulating signal corresponding to controlled silicon in the minimum conduction angle is reduced, thus the output current of a light-emitting diode (LED) and the brightness of the LED are reduced; and the influence on the width of the light regulating signal when the silicon controlled conduction angle is larger is less, thus the light regulating range is increased.

The invention discloses a multi-mode current control method and a dimming circuit and relates to the technical field of illumination. The multi-mode current control method comprises steps that a dimming signal is received, in response to the dimming signal, the dimming circuit is controlled for operating in various modes in any sequence, wherein the multiple modes comprise any two or all of a first dimming mode, a second dimming mode and a third dimming mode, and the dimming circuit can have different mode combinations according to actual requirements, and thereby the dimming requirements of awide dimming range and low output current ripples can be met.

The invention relates to a remote control dimmable energy-saving lamp which comprises an energy saving lamp casing (1), an energy saving lighting tube (2), a remote control emitter (3), a remote control signal receiving module (4) and an energy saving dimming control module (5); wherein, the remote control signal receiving module (4) and the energy saving dimming control module (5) are arranged in the energy saving lamp casing. The remote control dimmable energy-saving lamp is characterized in that the energy saving dimming control module (5) comprises a singlechip controller (51) and a dimming circuit (52); a signal output end of the remote control signal receiving module (4) is connected with a signal input end of the singlechip controller (51); the singlechip controller (51) outputs pulse modulation signals with different widths according to the received remote control signals, and the pulse modulation signals are connected with the signal input end of the dimming circuit (52) from the single output end of the singlechip controller (51); the dimming circuit (52) outputs different working voltages according to the received pulse modulation signals with different widths; and the working voltages are connected with the signal input end of the energy saving lighting tube (2) from the signal output end of the dimming circuit (52). Compared with the prior art, the remote control dimmable energy-saving lamp has the advantages that the energy saving lighting tube has stable lighting adjustment and large dimming range.

The invention belongs to the technical field of the visible light communication, and discloses a visible light communication light-dimming method based on a special constellation point and inverse-return-to-zero coding. The light-dimming method is mainly composed of special constellation point modulation, inverse-return-to-zero coding and pulse forming; the special constellation point modulation format is circular (7,1) modulation; the inverse-return-to-zero coding adopts the high level to replace the low level of the traditional return-to-zero coding, thereby maintaining that the LED is in the lighting state even if the duty ratio is less; the flicker capable of being sensed by the human eye is avoided while the luminous efficiency is effectively improved; and meanwhile, the return-to-zero coding can cause the broadening of the spectrum and is bad for the realization of the visible light communication with limited bandwidth, so that the pulse forming is used for filtering to achieve an aim of compressing the spectrum. Compared with the traditional light-dimming scheme, the method disclosed by the invention has higher luminous effect and wider light-dimming range, and the relatively high transmission rate can be maintained at the same time.

The invention provides an initial voltage adaptive method for a constant-voltage dimming power supply. The initial voltage adaptive method is characterized by comprising the steps of controlling the output voltage to be boosted slowly when the dimming power supply is started; monitoring the operating current of an LED through a current detection circuit connected with the to-be-driven LED in series; when the LED generates the operating current, processing the monitored operating current of the LED through a current processing circuit, wherein the operating voltage is the initial voltage of the LED, and under the initial voltage, the minimum LED dimming luminance is recorded and defined by external hardware or software; and the maximum LED dimming luminance of the dimming power supply is achieved at a rated constant voltage point of the constant-voltage dimming power supply. By adoption of the method, different types of LED lamp beads or modules can be adapted, so that the dimming power supply can realize changes from the minimum LED dimming to the maximum LED dimming directly, the adaptability of the power supply is greatly improved, and the dimming range of the LED is expanded; and therefore, the technical problems of decreased dimming range and matching failure with a driving power supply caused by the starting voltage differences of the LED lamp beads of the LED dimming power supply are solved.

The embodiment of the invention discloses a dimming method, an adjuster and a dimming system. The dimming method comprises the following steps: detecting the conducting situation of a main switch of a dimming switch; controlling a first current source and a second current source according to the conducting situation of the main switch, wherein when the main switch is conducted, judging whether the load voltage is less than a preset voltage value or not; if the load voltage is less than the preset voltage value, switching on the first current source; if the load voltage is not less than the preset voltage value, switching off the first current source and the second current source; when the main switch is switched off, switching on the first current source or the second current source, wherein the first current source and the second current source are in parallel connection, the first current source outputs a constant current, and the second current source outputs a variable current. The dimming method, the adjuster and the dimming system can increase the dimming range, reduce power consumption, and can guarantee flicker-free or shimmering loading under the circumstance of switching off the dimming switch.

The invention discloses a single-power-key time delay state control PWM dimming circuit used for an LED driver. The circuit comprises a power key, a T trigger, a time delay state circuit, a coding circuit, a state machine, a light intensity selection circuit and an out-gate circuit. The single power key is used for controlling an LED lamp to be turned on and off, the brightness of the LED lamp can be selected according to the interval time spent in pressing a switch, and compared with a traditional LED lamp with multiple keys, the LED lamp is simpler and more intelligent, and the size of a product can be reduced. The single-power-key time delay state control PWM dimming circuit is combined with a currently-popular PWM brightness regulation method, multiple brightness degrees are provided so as to be selected by a user, the dimming circuit can be directly applied to the LED driver in a PWM brightness regulation scheme, efficiency is higher than that of a traditional LED driver adopting a linear dimming method, the dimming range is wider, the brightness of the LED lamp can be accurately controlled, a design thought is novel, and the diming circuit accords with the intelligent development trend of future products.

A backlight module includes a switching unit, a resonance converting unit, a transformer and a lightening unit. The switching unit generates a switching signal according to a first control signal; the resonance converting unit is electrically connected with the switching unit for receiving the switching signal, and is provided with a first energy storing component and a switch component for controlling the switch component according to a second control signal and enabling the resonance converting unit to generate a resonance converting signal; the transformer is provided with a primary side winding and a secondary side winding, wherein the primary side winding is electrically connected with the resonance converting unit and the switching unit, and the transformer generates a driving signal according to the resonance converting signal and the switching signal; and the lightening unit is electrically connected with the secondary side winding and driven according to the driving signal.

The invention discloses a generalized dimming control method based on a multi-LED visible light communication system, and belongs to the field of wireless communication. The generalized dimming control method includes the steps: firstly, constructing a hybrid dimming module is constructed, initializing the number of space-time matrix activation elements, converting source bit information into a plurality of data blocks in a serial-parallel mode, mapping each data block into a space-time matrix, and transmitting the information through a visible light communication channel with the space-time matrix as a unit; calculating a direct current gain of the user channel matrix, and detecting and demodulating an electric signal receiving matrix obtained by conversion of the optical detector througha maximum likelihood detector; and calculating a joint boundary of corresponding system bit error rates when different numbers of elements are activated in the space-time matrix, and determining an optimal value of the number of the activation elements of the space-time matrix by taking the minimum bit error rate of the system as an optimization target and taking the dimming level and the spectral efficiency as constraint conditions. The generalized dimming control method effectively considers communication and lighting functions of the visible light communication system, can effectively improve the energy efficiency of the system, and can enhance the bit error rate performance of the system.

The invention provides a dimming circuit, a lamp component, a dimming system and a dimming method. The dimming circuit includes: a processing unit and a driving unit, wherein the input end of the processing unit is used for being connected with a central controller, the output end of the processing unit is electrically connected with the first input end of the driving unit, the second input end ofthe driving unit is used for being connected with a first power source, and the output end of the driving unit is used for connecting with M light source components in a lamp; the processing unit isused receiving dimming information sent by the central controller and is also used for acquiring target current ration information of the M light sources according to the dimming information and a preset ratio set; the driving unit is used for receiving the target current ratio information sent by the processing unit, and transmitting corresponding respective target dimming currents to the M lightsource components according to current provided by a first power supply and the target current ratio information. The dimming circuit, the lamp component, the dimming system and the dimming method allow lamps to be dimmed flexibly according to actual needs.

A projection display uses a light modulating device to modulate, in accordance with image data, light radiated from a light source, project the modulated light onto a screen, and display an image. The projection display separates a unit of time configuring the image data into an effective light time when the light modulating device can express the light as an image on the screen and an ineffective light time when the light modulating device cannot express the light as an image on the screen. The projection display increases the power supplied to the light source during the effective light time over the power supplied to the light source during the ineffective light time.