103 results about "Flicker-free" patented technology

The present invention relates to a system and method of viewing pairs of perspective images of 3-D objects (i.e. stereoscopic image pairs) displayed from a CRT display surface in a time-multiplexed or field-sequential manner, and more particularly to a universal method of generating control signals for synchronously changing the optical state of liquid crystal (LC) shutter panels through which the time-multiplexed perspective. images can be sequentially viewed in a substantially flicker-free manner by the left and right eyes of a human viewer, independent of whether the images are displayed on NTSC, PAL, VGA or SVGA styled CRT display devices.

An electronic ballast for high intensity gas discharge lamps where the wave form of the lamp current is square wave providing acoustic resonance and flickering free operation. The circuit, having high efficiency, operates in a wide temperature range providing ideal ballast curve and reliable ignition for the lamps. Furthermore, significant energy saving can be achieved by its externally controlled built in dimming capability.

The present invention relates to providing a flicker-free method and a control circuit for use in conjunction with a conventional AC dimmer coupled to a mains AC supply to continuously control an intensity of a Light Emitting Diode (LED) over substantially a full range of the dimmer, the control circuit comprising: a controllable source of DC voltage that is configured for coupling to at least one LED and that is powered independently of an output of the AC dimmer thereby isolating the LED voltage from the output of the AC dimmer; and a controller coupled to the source of DC voltage, the controller being powered independently of the output of the AC dimmer and being responsive to a firing angle of the AC dimmer for varying a level of the DC voltage as a function of said firing angle.

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.

A light guide bar with a patterned surface for a flicker free light source comprising a light emitting diode (LED) light source disposed on each end of the light guide bar is disclosed. A light diffusing pattern is disposed on a light emitting surface. The light diffusing pattern comprises a plurality of notches that are smallest closest to the LED light sources and largest in the center of the light guide bar. A light reflecting pattern is disposed on a light reflecting surface opposite the light diffusing pattern on the light emitting surface. Light emitted by the LED light sources enters the light guide bar through the ends. The light travels through the light guide bar at various angles and is reflected by the light reflecting pattern on the light reflecting surface. The reflected light is then emitted through the light diffusing pattern on the light emitting surface.

The invention provides a light-emitting diode (LED) eye-protecting lamp with multiple illuminators which comprises an LED area light source, a heat dissipating shell, a rotating shaft structure matched with a natural light sensor and a low-voltage direct current drive controller used for adjusting brightness. The LED eye-protecting lamp with multiple illuminators has the advantages that adjustment control function is intelligent, low-voltage input is safe, appearance of the eye-protecting lamp can be designed variously, problems of direct glare of the light source illuminators and indirect glare of the lighting device are solved under the condition that high-light of the eye-protecting lamp is ensured, structure is reasonable and compact, manufacturing is convenient, purposes of energy-efficient, environmental protection, conscious, flicker-free, no radiation, no glare, no shadows and no light pollution are achieved truly, and the LED eye-protecting lamp with multiple illuminators has high social benefits and economic benefits.

A method for flicker detection based on a plurality of images and associated circuit is provided. The method includes providing an integrated flicker signal for each image, including accumulating pixel data of a number of pixels along each row; performing a motion compensation including: comparing two integrated flicker signals of two images, and accordingly providing a flicker signal difference; performing a flicker feature extraction including: applying a frequency analysis on the flicker signal difference, and accordingly providing a normalized flicker feature value; and performing a flicker determination, including: calculating a likelihood according to the normalized flicker feature value, and, according to the likelihood, determining whether a flicker-free hypothesis should be rejected in favor of a flicker-suffered hypothesis.

A flicker-free method and a control circuit is used in conjunction with a conventional AC dimmer coupled to a main-AC supply to continuously control an intensity of a Light Emitting Diode (LED) over substantially a full range of the dimmer. The control circuit has a controllable source of DC voltage that is configured for coupling to at least one LED and that is powered independently of an output of the AC dimmer thereby isolating the LED voltage from the output of the AC dimmer; and a controller coupled to the source of DC voltage. The controller is powered independently of the output of the AC dimmer and is responsive to a firing angle of the AC dimmer for varying a level of the DC voltage as a function of said firing angle.

A direct interaction stereoscopic display system that produces an augmented or virtual reality environment. The system comprises one or more displays, a beam combiner, and a mirrored surface to virtually project high-resolution flicker-free stereoscopic 3D imagery into a graphics volume in an open region. Viewpoint tracking is provided enabling motion parallax cues. A user interaction volume co-inhabits the graphics volume and a precise low-latency sensor allows users to directly interact with 3D virtual objects or interfaces without occluding the graphics. An adjustable support frame permits the 3D imagery to be readily positioned in situ with real environments for augmented reality applications. Individual display components may be adjusted to precisely align the 3D imagery with components of real environments for high-precision applications and also to match accommodation-vergence distances to prevent eye strain. The system's modular design and adjustability allows display panel pairs of various sizes and models to be installed.

Apparatuses and methods for image sensors with pixels that reduce or eliminate flicker induced by high intensity illumination are disclosed. An example image sensor may include a photodiode, a transfer gate, an anti-blooming gate, and first and second source follower transistors. The photodiode may capture light and generate charge in response, and the photodiode may have a charge capacity. The transfer gate may selectively transfer charge to a first floating diffusion, and the anti-blooming gate may selectively transfer excess charge to a second floating diffusion when the generated charge is greater than the photodiode charge capacity. The first source-follower transistor may be directly coupled to the first floating diffusion by a gate, the first source-follower to selectively output a first signal to a first bitline in response to enablement of a first row selection transistor, and the second source-follower transistor may be capacitively-coupled to the second floating diffusion, the second source-follower to selectively output a second signal to a second bitline in response to enablement of a second row selection transistor.

The flicker-free linear LED driver circuit with high power factor has a rectifier unit, an LED unit, a constant current unit, a storage capacitor and a voltage controlled transistor; the rectifier unit is connected to an AC power and converts the AC power into a pulsating DC power; the LED unit is connected to the rectifier unit and has multiple LED sources; the constant current unit is connected in series with the LED unit to form a first power circuit; wherein current flowing in the LED unit is fixed to a constant value by the constant current unit; the storage capacitor is connected to the rectifier unit; the voltage controlled transistor is connected in series with the storage capacitor to form a second power circuit; wherein the voltage controlled transistor limits current flowing in the storage capacitor under a maximum current limit value.

The invention discloses a WLED (White Light Emitting Diode) driving circuit and method suitable for a triode-thyristor light modulator. In the driving circuit and method, a novel electronic transformer is provided and can be used for detecting the conduction angle of high-voltage alternating current output by the triode-thyristor light modulator and converting the high-voltage alternating currentinto PWM (Pulse-Width Modulation) low-voltage direct current with a duty cycle regulated by the conduction angle. The PWM low-voltage direct current supplies power to a WLED driver so as to drive a WLED to work; and the triode-thyristor light modulator can be regulated to regulate average current flowing through the WLED so as to change the brightness of the WLED. The PWM low-voltage direct current contains no alternating-current voltage ripples with the frequency of 50Hz and below, and thus, the WLED driving circuit and method suitable for the triode-thyristor light modulator successfully realize the smooth flicker-free light modulation for the WLED.

A display apparatus having a pair of polarizers with an optical rotator therebetween, one of the polarizers being a variable polarizer which is independently operated to alternate between substantially orthogonal states of polarization and cause the display to rapidly alternate between a normal positive and inverted negative image, creating a combined neutral image that in indecipherable to the naked eye. Shutter eyewear synchronized with the variable polarizer is used to extract the positive image for viewing by an intended viewer. In another embodiment, both polarizers of the display apparatus are independently variable, which allows for viewing of the desired image using passive polarized eyewear or eyewear incorporating synchronized variable polarizing rotators. Faster independent operation of the variable polarizers provide for flicker-free viewing of the desired image and convenient switching between normal and secure modes of operation, without physical alteration of the display.

A method for converting graphic elements containing sparse graphs into graphic layers is described, comprising the steps of: correspondingly mapping respective sparse graphs to respective sparse graphic layers, and projecting sequentially from top to bottom the regular graphs between the sparse graphs into a projection plane to form a regular graphic composition layer. Also described is a method for fast flicker-free displaying overlapped sparse graphs with optional shape, comprising: converting graphic element containing sparse graphs to be displayed into graphic layers; deciding whether to plot or erase the sparse graph to be displayed, and, when the sparse graph is decided to be erased, setting various points on the corresponding sparse graph to be transparent; and completing the plotting of points of the sparse graph point by point based on the shape of the sparse graph to be displayed. Apparatuses corresponding to the above methods are also described.

A compression algorithm, utilizing a new concept called “shared pixel parts”, allows for transmitting, receiving, and displaying full HD stereoscopic 3-D video with no loss of resolution or frames to either eye, using a single conventional TV channel and any type of conventional display without alteration. Depending on the type of display, viewers wear either passive polarized glasses, a new type of static colored-filter glasses, or a new type of active colored-filter glasses to view the same data signal showing virtually ghost-free full-color images with great depth, a wide angle of view, and a bright flickerless image which doesn't produce any discomfort even after extended viewing. The signal is also compatible with current 3-D-ready TVs. The compression algorithm can also be used to transmit and display a 2-D image with double the resolution of the display being used for viewing, with no increase of required transmission bandwidth.

The driving of an active matrix organic light emitting display (AMOLED) shall be improved. A pulsing grayscale rendition shall be combined with an improved motion rendition when driving the AMOLED with analog signals. Therefore, there is provided a data signal which is applied to each cell of the AMOLED for displaying a first grayscale level of a pixel of the image during a first group of sub-frames (SFO to SF5) for displaying at least a second grayscale level of a pixel of the image during at least a second group of sub-frames (SF' 0 to SF' 5). The first group of sub-frames (SFO to SF5) and the at least second group of sub-frames (SF' 0 to SF' 5) are constituting a video frame N. Each group of sub-frames is divided into a plurality of sub-frames. Each of the first group of sub-frames and the second group of sub-frames is belonging to a separate complete image of the display (AMOLED). The data signal of a cell comprises plural independent elementary data signals wherein each of the elementary data signals is applied to the cell during a sub-frame and the grayscale level displayed by the cell during the respective group of sub-frames depends on the amplitude of the elementary data signals and the duration of the sub-frames. With this concept, a flicker-free and a very high level motion rendition can be offered.

A drive circuit device for a flicker-free LED is revealed. It comprises a drive circuit having a rectifier connecting to an AC power supply and to a plurality of LEDs in series, wherein each of the plurality of LEDs is disposed in parallel with a multilayer capacitor.

The invention relates to video processing technology. The technical problem to be solved is to provide a field interpolation method for determining interpolation direction by considering more angle pixel correlations and eliminating isolated point noise. The reference angle of the invention picks up nine directions, namely four small angle directions and five adjacent directions. If a small angle is chosen for interpolation in certain areas with small pixel correlation difference, noise points can be introduced to the area. Therefore, as long as the pixel correlation in adjacent directions achieves a first preset value, the small angle factor can not be considered to interpolate in the largest pixel correlation in five adjacent directions. If the small angle is considered, whether the pixel correlation of the supplementary angle of the small angle is smaller than a second preset value is determined, if yes, the small angle is selected; and if not, the largest pixel correlation direction in the five adjacent directions is chosen for interpolation. The method can acquire results of smooth edges and flicker-free details.

A flicker-free LED driver circuit with a high power factor has a rectifying unit connected with an AC power source, an LED module connected in series with the rectifying unit, a capacitor module connected in parallel with the LED module, and a constant current circuit connected in series with the LED module and the capacitor module. When the voltage output by the rectifying unit is smaller than a junction voltage of the LED module, the capacitor module discharges to the LED module so that the LED module does not go out, thereby eliminating the flickering. The input impedance of the rectifying unit can be regarded as a capacitive reactance element connected in parallel with a nonlinear resistive element. The internal resistance of the constant current source approaches infinity. Therefore, the power factor of the flicker-free LED driver circuit approximates 1, achieving a high power factor.

The invention relates to an LED circuit, which comprises a power factor control and voltage boosting unit, an LED lamp, and a voltage reduction unit which are connected in turn, a control unit which is connected with the power factor control and voltage boosting unit, the LED lamp, and the voltage reduction unit, and a detection unit, wherein the power factor control and voltage boosting unit and the voltage reduction unit independently work. On the basis of constant current output, the LED circuit can also adjust the phase difference between input voltage and loop current so as to greatly correct power factors and obtain high work efficiency; and compared with the prior art, the LED circuit has flicker-free adjust luminance, good stability and high reliability.

The invention discloses an implementation method of a breathing lamp in intelligent equipment application notification. The method comprises the following steps of: performing application notification by intelligent equipment; determining whether a screen is bright or not; if the fact that the screen is bright is determined, entering a flicker-free breathing lamp; if the fact that the screen is not bright is determined, entering the next step; determining whether an application notification switch is opened or not, if the fact that the application notification switch is opened is determined, entering the flicker-free breathing lamp, and, if the fact that the application notification switch is not opened is determined, entering the next step; obtaining the colour and the frequency of the application notification, and sending the colour and the frequency of the application notification to the breathing lamp; flashing by the breathing lamp according to the colour and the frequency; and judging the important level of the application notification by users according to the colour and the frequency of the flashing lamp, and judging whether the intelligent equipment needs to be unlocked or not according to the important level. Due to improvement of the implementation method disclosed by the invention, users can judge the notification level according to the frequency of the breathing lamp; unimportant notification can be ignored; a mobile phone does not need to be unlocked; when ordinary notification is reminded, the breathing lamp can automatically stop after flashing for a certain time; therefore, the electric quantity can be saved; and the anti-disturbance effect also can be realized.

The invention discloses a spare power automatic switching method and device, wherein the method comprises the following steps that current input signals and voltage input signals which are obtained through proportionally converting collected current signals and voltage signals of an on-site switch and can be recognized by a microprocessor assembly are obtained; switch operation parameters which are obtained through converting collected operation parameters of the in-site switch and can be recognized by the microprocessor assembly are obtained; switch control information is generated according to the current input signals, the voltage input signals and the switch operation parameters; the on-off state change of the in-site switch is controlled according to the switch control information, wherein the on-off state change of the in-site switch is used for switching a spare power supply to the work state when a main power consumption power supply fails, and is also used for switching the main power consumption power supply to the work state when the main power consumption power supply recovers the normal state. The method and the device have the advantages that the problem of spare power automatic switching inaccuracy is solved, and the effect of accurate, flickering-free and fast spare power automatic switching is realized, and the realized functions are complete.

The invention provides an active soft switch half bridge method, which is characterized in that: a push-pull type BUCK topology is adopted and connected in series in a main circuit of a half bridge topology through two inductors Lo1 and Lo2; auxiliary switches VS11 and VS12 are used for respectively carrying out CUK to actively realize the zero-voltage disconnection of ZVS soft switch; main switches VS1 and VS2 are respectively connected in series with the small magnetic integrated inductors Lo1 and Lo2 to form zero-current conducting of ZCS soft switch; passing through a load RO, output alternating current is then connected in series with a current-limiting inductor Lr and reaches a middle point P of half bridge capacitors C1 and C2, to form a push-pull type BUCK half bridge topology. The active soft switch half bridge can eliminate the straight-through dangers in the traditional half bridge circuits, effectively improve the reliability and electrical efficiency and reduce EMC interference levels, and can be widely used in LED lamps, HID lamps, single-phase, two-phase or three-phase flicker free fluorescent lamps, single-phase, two-phase or three-phase power electronic transformers and brushless direct current motors or frequency transformers of two-phase and three-phase motors and the like.

The invention discloses a thin integrated 3D three-dimensional display polarizer and a preparation method thereof. In the protective film layer, the slow axis of the even-numbered lines of the micro-retardation film and the transmitted optical axis of the polyvinyl alcohol film layer are 0° to 50° or 130° to 180°, and the slow axis of the odd-numbered lines of the micro-retardation film and the polyethylene The transmission optical axis of the alcohol film layer is arranged at an angle of 130°-180° or 0°-50°, and the micro-retardation film is treated with anti-glare AG, anti-reflection AR / LR or anti-scratch HC. The polarizer of the present invention can convert the linearly polarized light emitted by the liquid crystal display panel into two sets of independent, intersecting left and right circularly polarized lights to form left and right images, and the audience only needs to wear simple and cheap circularly polarized glasses to watch the colors Pure, flicker-free 3D display images, and the polarizer of the present invention has thin thickness and high optical transmittance.

The invention discloses a frequency-flicker-free LED filament lamp comprising a linear constant-current drive power supply and an LED luminous body. The drive power supply is composed of an over-current protection unit, a rectifier and filter unit, a linear constant-current unit, a constant-current filter unit, and a frequency flicker elimination unit used for converting the output current of the constant-current filter unit into direct current without current ripple. AC mains power is connected into the input end of the over-current protection unit. The output end of the over-current protection unit is connected with the input end of the rectifier and filter unit. The output end of the rectifier and filter unit is connected with the input end of the linear constant-current unit. The output end of the linear constant-current unit is connected with the input end of the constant-current filter unit. The output end of the constant-current filter unit is connected with the input end of the frequency flicker elimination unit. The output end of the frequency flicker elimination unit is connected with the LED luminous body. The advantage lies in that because of the introduction of the frequency flicker elimination unit, current ripple of constant current is eliminated, the precision of constant current is high, and therefore, there is no frequency flicker during light emission of the LED high-voltage filament in the LED luminous body.