CN110211523A - A kind of method, apparatus and system of telemeasurement Flicker value of liquid crystal module - Google Patents
A kind of method, apparatus and system of telemeasurement Flicker value of liquid crystal module Download PDFInfo
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- G09G3/36—Control arrangements or circuits, of interest only in connection with visual indicators other than cathode-ray tubes for presentation of an assembly of a number of characters, e.g. a page, by composing the assembly by combination of individual elements arranged in a matrix no fixed position being assigned to or needed to be assigned to the individual characters or partial characters by control of light from an independent source using liquid crystals
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Abstract
The invention belongs to display panel detection technique fields, disclose the method, apparatus and system of a kind of telemeasurement Flicker value of liquid crystal module, to display picture continuous capture of the liquid crystal module under certain public electrode voltages, obtain the average brightness of picture frame, the brightness is obtained with acquisition frame number or the variation relation of the time i.e. time-domain signal of brightness, the spectrogram of brightness is obtained by time-domain signal, Flicker flicker value of the LCD module under test under the public electrode voltages is obtained by the amplitude of specific frequency wave；Its device includes for the equipment to the continuous capture of picture of the liquid crystal module under certain public electrode voltages, the calculation processing module for obtaining the time-domain signal of brightness for calculating average brightness, the fourier transformation module that Fast Fourier Transform (FFT) is carried out for the time-domain signal to brightness, for calculating the Flicker flicker value computing module of Flicker flicker value；This method and system can telemeasurement display screen Flicker flicker value, the flicker degree for the real-time monitoring liquid crystal display in panel production line.
Description
Technical Field
The invention belongs to the technical field of liquid crystal display panel detection, and particularly relates to a method, a device and a system for remotely measuring a Flicker value of a liquid crystal module.
Background
Thin film transistor liquid crystal displays (TFT-LCDs) are playing a significant role in the display industry. The TFT-LCD controls the deflection of liquid crystal molecules by applying different voltages to the pixel electrodes and forming an electric field with a Common electrode, namely a Common electrode, thereby achieving the purposes of light transmission and light shielding. The voltage difference between the pixel electrode and the Common electrode determines the display gray scale. When the TFT-LCD works, the polarity of the pixel voltage is periodically changed to avoid the DC residue and the DC blocking effect. The polarity of the pixel voltage changes once every time the LCD picture is refreshed, if the Common electrode voltage (V)com) From the optimum value, when the polarity of the pixel voltage changes, it is associated with VcomThe absolute voltage difference of the voltage changes along with the change of the absolute voltage difference, so that the same picture presents different brightness when the picture is refreshed, namely Flicker appearsSuch as a mouse. When the Flicker phenomenon is serious, the risk of image residue generated by the liquid crystal panel is increased, the display quality is reduced, and the physiological discomfort of a viewer is caused, so that the Flicker value of the Flicker panel needs to be detected and controlled within a preset range in the TFT-LCD production process.
The idea of measuring the Flicker value of the liquid crystal module disclosed by the prior art is to convert a flickering optical signal of the LCD module into an alternating current signal, convert the alternating current signal into a direct current signal with the same energy as the alternating current signal, and calculate the Flicker value of the liquid crystal module by integrating the alternating current and direct current analysis results; or when the liquid crystal module displays Flicker picture, the analog brightness waveform signal of the liquid crystal module is scanned and converted into a digital brightness waveform signal, and a specific frequency wave (V) is obtained through a Fourier transform devicecomSwitching frequency of the signal), and calculating by a formula to obtain a Flicker value. In the detection process, the brightness of the LCD module needs to be measured by scanning the LCD module by using measuring heads such as an optical probe, the optical probe needs to be as close as possible to or attached to a screen for measurement so as to reduce external interference, and only the panel range covered by the measuring heads can be detected each time, so that the requirement of remotely detecting the Flicker value of a large-area display panel Flicker in a production line is difficult to meet, and the detection time is long; on the other hand, the method can only ensure accurate data when the measurement distance is not more than 100mm, and cannot accurately measure the Flicker value of the liquid crystal module at a longer distance.
The method and the device (CN 109147709A) for multipoint adjusting the Flicker of the liquid crystal panel, which are previously applied by the applicant, carry out Fourier transform on signals of brightness and frame rate to obtain a Flicker value; the scheme is not enough in that the number of the collected frames is limited, the number of the frames which need to be collected when the Flicker value is actually applied to detection is large, and the detection efficiency of a production line is not high.
Disclosure of Invention
Aiming at the defects or improvement requirements in the prior art, the invention provides a method, a device and a system for remotely measuring the Flicker value of a liquid crystal module.
To achieve the above object, according to one aspect of the present invention, there is provided a method for remotely measuring Flicker value of a liquid crystal module, comprising:
to the voltage V of a common electrode of the liquid crystal module to be testedcomContinuously taking images of the lower display picture at a fixed frame rate, and calculating the average brightness of each obtained image frame so as to obtain the change relation of the average brightness of the liquid crystal module along with the collection frame number or time, namely a time domain signal of the brightness; the fixed frame rate is more than twice of the refreshing frequency of the liquid crystal module;
the acquisition time and the acquisition frame number of the image are not limited, the acquisition frame number can be far smaller than the frame rate of the camera, as long as the time domain image does not lose frames, and the efficiency is very high when the method is applied to the detection of an actual production line;
obtaining a brightness spectrogram by performing Fast Fourier Transform (FFT) on the time domain signal of the brightness, and obtaining the voltage V of the liquid crystal module to be tested on the common electrode through the amplitude of a specific frequency wavecomFlicker value below; the specific frequency wave is a frequency domain signal of the Flicker signal, and is present at the first side lobe of the frequency spectrum in a preferred embodiment, and the Flicker value is obtained based on the linear relation between the amplitude and the Flicker value. In another preferred embodiment, the Flicker signal appears on the spectrogramObtaining a Flicker value according to the linear relation between the amplitude and the Flicker value; wherein,refers to the refresh rate of the module under test.
Preferably, the method for remotely measuring Flicker value of the liquid crystal module judges whether a frame loss occurs in the image capturing process by the following method:
and obtaining the occurrence frequency of Flicker in the spectrogram based on the acquisition frame number, the image capturing frame rate and the module refreshing frequency, judging whether the occurrence frequency of Flicker in the spectrogram is correct, and if not, indicating that the image capturing process has a frame missing phenomenon.
Preferably, the method for remotely measuring Flicker value of the liquid crystal module judges whether a frame loss occurs in the image capturing process by the following method:
and acquiring Flicker period number in a time domain graph of the brightness based on the acquisition frame number, the image capturing frame rate and the module refreshing frequency, judging whether a lost frame exists in the image capturing process according to whether the Flicker period number in the time domain graph is correct, and if not, indicating that the lost frame phenomenon exists in the image capturing process.
The Flicker signal appears at a specific frequency in a spectrogram, and an accurate Flicker value can be obtained only by ensuring no frame loss in the image capturing process; under the condition that the refresh rate of a panel, the frame rate of a camera and the number of acquisition frames are determined, the number of Flicker periods which should appear in a brightness time domain graph under the condition of no frame loss is determined.
Preferably, in the method for remotely measuring Flicker of liquid crystal module, when a frame loss occurs, the currently acquired image is discarded, and the voltage V of the liquid crystal module to be measured at a certain common electrode is measured againcomContinuously capturing images of the display frame, and obtaining the voltage V of the common electrode by the method for remotely measuring Flicker value of the liquid crystal modulecomAnd the Flicker value of the following Flicker to ensure the accuracy of the Flicker value obtained by measurement.
To achieve the object of the present invention, according to another aspect of the present invention, there is provided an apparatus for remotely measuring Flicker value of a liquid crystal module, comprising:
a continuous image-taking device for applying a common electrode voltage V to the LCD modulecomContinuously taking the images of the lower pictures;
the calculation processing module is used for calculating the average brightness of each obtained image frame to obtain the change of the average brightness of the LCD liquid crystal module along with the frame number or time, namely a time domain signal of the brightness;
the Fourier transform module is used for performing Fast Fourier Transform (FFT) on the time domain signal of the brightness to obtain a spectrogram of the brightness;
a Flicker value calculating module for finding the peak amplitude corresponding to the frequency of the Flicker signal in the spectrogram and further obtaining the voltage V of the common electrode according to the amplitudecomFlicker value below.
Preferably, the device for remotely measuring Flicker value of a liquid crystal module further comprises a lost frame detection module, wherein the lost frame detection module is configured to obtain a frequency of Flicker in the spectrogram based on the acquisition frame number, the image capture frame rate, and the module refresh frequency, determine whether the frequency of Flicker in the spectrogram is correct, and otherwise indicate that a lost frame phenomenon exists in the image capture process.
The method for acquiring the Flicker frequency in the spectrogram based on the acquisition frame number, the image acquisition frame rate and the module refreshing frequency and judging whether the frame is lost or not according to the correctness of the Flicker frequency has no requirement on the acquisition frame number, and can accurately judge whether the frame is lost or not even if fewer frames are acquired.
Preferably, the device for remotely measuring the Flicker value of the liquid crystal module further comprises a lost frame detection module, wherein the lost frame detection module is used for obtaining the Flicker period number in a time domain graph of the brightness based on the acquisition frame number, the image capturing frame rate and the module refreshing frequency, judging whether a lost frame exists in the image capturing process according to whether the Flicker period number in the time domain graph is correct, and if not, indicating that the lost frame phenomenon exists in the image capturing process.
The Flicker period number in the time domain graph of the brightness is obtained based on the acquisition frame number, the image acquisition frame rate and the module refreshing frequency, and whether the frame is lost in the image acquisition process is judged according to whether the Flicker period number is correct or not. Preferably, in the device for remotely measuring Flicker value of liquid crystal module, the Flicker value calculating module and the frame loss detecting module have signal interaction, and when a frame loss occurs, the currently acquired image is discarded, and the voltage V of a certain common electrode of the liquid crystal module to be measured is measured againcomContinuously capturing images of the display frame, and obtaining the voltage V of the common electrode by the method for remotely measuring Flicker value of the liquid crystal modulecomAnd the Flicker value of the following Flicker to ensure the accuracy of the Flicker value obtained by measurement.
To achieve the object, according to another aspect of the invention, a system for remotely measuring Flicker value of liquid crystal module Flicker is provided, which comprises
The image capturing device is used for continuously capturing images of the liquid crystal module under certain common electrode voltage;
further comprising a processor, a memory, and a computer program stored in the memory and executable on the processor;
the computer program, when executed by a processor, controls an image capturing apparatus to implement the method according to any one of claims 1 to 4.
In general, compared with the prior art, the above technical solution contemplated by the present invention can achieve the following beneficial effects:
compared with the conventional method for measuring the Flicker value of the display screen by sticking a probe to the display screen, the method adopts image acquisition equipment such as a camera to remotely acquire images for measurement, and the image acquisition distance does not influence the acquired time domain signal and frequency domain signal, so that the method is insensitive to the distance between the acquisition device and the screen to be measured and does not influence the measurement of the Flicker value of the Flicker, and therefore, the method can be used for remotely detecting the Flicker value of the LCD liquid crystal module; in addition, the method can quickly calculate and obtain the Flicker value of the Flicker only by taking the picture, can realize quick detection and meet the requirement of quick measurement of the Flicker value in a panel production line;
the method, the device and the system for remotely measuring the Flicker value of the display screen realize remote measurement, can be realized by only erecting an image acquisition device such as a camera in a production line, do not need to use a measuring head to be attached to a screen to be measured for measurement like other measuring methods, and are more suitable for online detection; the device can be used for a production line to quickly measure a plurality of screens, and is beneficial to improving the detection efficiency and the production yield;
in comparison, the existing display screen Flicker value measuring technology needs a measuring probe or an optical probe to scan the screen to be measured in a short distance, even needs to be measured by adhering to a screen body, can only detect the Flicker value of the Flicker with a limited area, and needs to be additionally provided with a shading part; the method, the device and the system have no requirement on the testing distance, have no strict requirements on the measuring distance, the selection of the ROI (region of interest) of a camera shooting picture, the focusing degree of the camera and the like, can obtain the Flicker value of the Flicker with a larger ROI of a screen body at a long distance, and have wider application range.
Compared with the prior art of the method and the device (CN 109147709A) for adjusting the Flicker of the liquid crystal panel at multiple points, which are previously applied by the applicant, which adopt the scheme of carrying out Fourier transform on signals of brightness and frame rate to obtain the Flicker value, the method, the device and the system for remotely measuring the Flicker value of the display screen have the technical scheme of fixing the frame rate of a camera, carrying out Fourier transform on signals of brightness and acquisition frame number or time to obtain the Flicker value, do not limit the acquisition frame number, have controllable measurement time, greatly shorten the measurement time of the Flicker value by reducing the acquisition frame number, and greatly improve the detection efficiency when being applied to an actual production line.
Drawings
FIG. 1 is a schematic flow chart of a method for remotely measuring Flicker of a liquid crystal module according to an embodiment of the invention.
FIG. 2 is a time domain graph showing the average brightness of the LCD display screen obtained in the example.
FIG. 3 is a spectrum diagram showing the average brightness of the LCD panel obtained in the example.
FIG. 4 is a schematic diagram of Flicker signal misalignment in a spectrogram in the presence of an out-of-frame condition in an example.
FIG. 5 is a spectrum diagram of the brightness obtained by plotting the position of the camera focus ring at 2.8m according to the embodiment.
FIG. 6 is a spectrum diagram of the brightness obtained by plotting the position of the camera focus ring at 8m according to the embodiment.
Fig. 7 is a luminance spectrum diagram obtained by photographing a luminance signal of an LCDFlicker picture under flicker-free natural illumination in an example.
Fig. 8 is a luminance spectrum obtained by photographing a luminance signal of an LCDFlicker picture in a dark room in an example.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention. In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
The invention provides a method, a device and a system for remotely measuring Flicker value of a liquid crystal module, which are characterized in that the voltage V of a certain common electrodecomContinuously taking pictures or shooting video files on the display screen by using image acquisition equipment such as a camera and a video camera, and calculating the average brightness of each frame so as to obtain the time domain signal of the brightness, wherein the average brightness of the display screen changes along with the frame number or time; obtaining a spectrogram of the brightness by performing fast Fourier transform on a time domain signal of the brightness; finding the peak amplitude corresponding to the frequency of the Flicker signal in the spectrogram, and further obtaining the voltage V of the common electrode according to the linear relation between the amplitude and the Flicker value of the FlickercomFlicker value below.
The method for remotely measuring the Flicker value of the liquid crystal module provided by the embodiment is based on a camera to carry out remote measurement, and the process of the method refers to fig. 1, and comprises the following steps:
(1) applying a camera to LCD liquid crystal module at a certain common electrode voltage V at a fixed frame ratecomAcquiring a group of videos or continuous shooting pictures of the lower picture; in one example, the LCD display screen resolution is 60Hz, the camera sampling frame rate is set to 120Hz or above, and the Nyquist sampling law is satisfied;
the camera can be in a focusing or defocusing state, the distance between the camera and the LCD display screen is not required, and the reference is to normally shoot a flickering picture of the LCD display screen; the imaging environment is in natural light without flickering light or in a dark room.
(2) Calculating the average brightness of each frame of the collected video frame, thereby obtaining the variation relation of the average brightness of the LCD display screen along with the frame number, namely a time domain signal of the average brightness of the LCD display screen illustrated in FIG. 2;
(3) performing fast Fourier transform on the time domain signal to obtain a spectrogram of brightness, and finding out the peak amplitude corresponding to the frequency of the Flicker signal in the spectrogram; ginseng radix (Panax ginseng C.A. Meyer)FIG. 3 shows the amplitude of the first side lobe in the spectrogram of the voltage V at the common electrodecomFlicker value below; the frequency of the Flicker signal is the refreshing frequency of the LCD screen1/2 of (1); the corresponding position of the Flicker signal on the spectrogram is not unique, and in other preferred embodiments, the frequency of the Flicker signal corresponds to other convex peaks on the spectrogram and is in a linear relationship with the refresh frequency of the LCD screen.
(4) Obtaining the voltage V of the common electrode according to the linear relation between the peak amplitude and Flicker valuecomFlicker value below.
In order to satisfy the Nyquist sampling law, the frame rate of the sampling device needs to be more than twice of the refreshing frequency of the display screen; the time domain signal is a relation graph of the image brightness average value and the collection frame number, the collection frame number is not limited, the collection frame number can be far smaller than the camera frame rate, as long as the time domain image does not lose frames, the Flicke value detection can be completed by collecting as few frames as possible on the premise of not losing frames, and the measurement time consumption is greatly reduced; when the method is applied to the detection production line, the detection efficiency can be greatly improved by the optimization, and the time and the economic cost for detecting the production line are saved.
In a preferred embodiment, after the step (2) and before the step (3), a step of frame loss detection is further included, and whether a frame loss phenomenon occurs in the data acquisition process is judged according to whether the Flicker cycle number in the luminance time domain graph or the Flicker frequency in the luminance frequency spectrum graph is correct; if no lost frame exists, entering the step (3); otherwise, the step (1) is carried out to continue the acquisition, so that the Flicker value is obtained under the condition that no frame loss occurs in the image capturing process.
The embodiment of the invention judges whether the frame loss exists in the image capturing process by judging whether the Flicker frequency in the frequency spectrogram is correct or not or whether the Flicker period number in the time domain chart is correct or not, and ensures that the Flicker value is obtained under the condition of no frame loss in the image capturing process, thereby improving the measurement accuracy of the Flicker value of the liquid crystal module.
Specifically, one of the lost frame determination methods used in the embodiments is: judging whether the occurrence frequency of Flicker in the spectrogram is equal toIf not, judging that the image-taking process has the frame-missing phenomenon,the refresh rate of the module under test.
Referring to FIG. 4, in this test example, the LCD display refresh rate is 60Hz and the Flicker signal should appear in the spectrum at 30 Hz; while a missing frame occurs in the test process, the position of the occurrence of the Flicker signal is obviously observed to deviate from 30Hz and to be closer to 20Hz in the spectrogram.
Another method for judging frame loss is as follows: and judging whether a frame is lost in the image acquisition process or not according to whether the oscillation number of the signals in the time domain image, namely the Flicker period number, meets the requirement correctly, and if not, judging that the frame is lost in the image acquisition process. In one embodiment, the method for obtaining Flicker cycle number in a time domain graph of brightness based on the acquisition frame number, the image capturing frame rate and the module refreshing frequency specifically comprises the following steps:
flicker cycle number = number of acquisition frames/fcam ((r))) (ii) a Where fcam is the frame rate of the acquisition device, such as a camera,the refresh rate of the module under test.
The embodiment provides the method for remotely measuring the Flicker value of the liquid crystal module and the focusing state of the image acquisition equipmentThe Flicker value measurement is not influenced, and the measurement of the Flicker value is not influenced when the camera focuses or shoots the LCD picture by a virtual focus. The Flicker signal is obtained by changing the focusing state of the focusing ring of the camera lens, and the voltage V is the same as the common electrodecomThe spectrograms of different focusing states are shown in fig. 5 and 6, fig. 5 shows a luminance spectrogram obtained by drawing at a position of 2.8m of a camera focusing ring, and fig. 6 shows a luminance spectrogram obtained by drawing at a position of 8m of the camera focusing ring, so that the luminance spectrograms of the two are basically consistent, the relative amplitude difference of the obtained Flicker signal is only 0.0063, and the focusing state does not influence Flicker value measurement.
Referring to FIGS. 7 and 8, the voltage V of the common electrode is the same in the dark room and under the natural illumination without flickercomAnd shooting the brightness signal of the Flicker picture of the LCD display screen at the same position under the focusing state and the working distance, and further obtaining a spectrogram, wherein the brightness spectrograms of the LCD display screen and the working distance are almost the same, and the relative amplitude of the Flicker signal is only 0.00043 different, which shows that the consistency of the measurement result shot in a darkroom and the Flicker-free natural light environment is very high.
In one embodiment, when calculating the average brightness of each frame to obtain the time domain signal of the brightness, the size of the ROI of the selected picture can be customized, and the method is not limited to the average brightness of the whole picture, and the user can select the whole picture or select a part of the ROI in the picture according to the area of the screen body to be detected to perform the subsequent processing of obtaining the Flicker value of Flicker.
The existing Flicker measuring device needs a measuring probe or an optical probe to scan a screen to be measured in a short distance, even needs to be measured by being attached to a screen body, and some devices need a shading part to prevent external light interference; the method for remotely measuring the Flicker value of the liquid crystal module, provided by the embodiment of the invention, includes the steps of firstly obtaining a time domain signal of the brightness of a display screen in a mode of continuously taking images or collecting a group of videos through an image collecting device such as a camera, and obtaining a frequency domain signal of the time domain signal of the brightness through FFT based on lost-frame-free image collection, so as to find a peak value of the Flicker signal in a spectrogram; the requirement on the testing distance is not required, the measured value consistent with that of darkroom shooting can be obtained under the condition of no-Flicker natural illumination, and the Flicker value of a Flicker with a larger ROI of the screen body can be obtained during the remote measurement; the Flicker value of the Flicker of the remote measurement display screen is realized, the blank in the technical field is filled, the Flicker degree of the liquid crystal display screen can be monitored in real time in an LCD production line, and the improvement of the detection efficiency and the panel production yield is facilitated.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (9)
1. A method for remotely measuring Flicker value of a liquid crystal module is characterized by comprising the following steps:
continuously taking images of a display picture of a liquid crystal module to be tested under a certain common electrode voltage at a fixed frame rate, acquiring the average brightness of the image frames, and obtaining the change relation of the average brightness along with the acquisition frame number or time, namely a time domain signal of the brightness; the fixed frame rate is more than twice of the refreshing frequency of the liquid crystal module to be tested;
and transforming the time domain signal to obtain a spectrogram of brightness, and obtaining a Flicker value of the liquid crystal module to be tested under the voltage of the common electrode through a frequency domain signal amplitude corresponding to a Flicker signal on the spectrogram.
2. The method for remotely measuring Flicker value of a liquid crystal module as claimed in claim 1, wherein the method comprises the following steps of:
and obtaining the occurrence frequency of Flicker in the spectrogram based on the acquisition frame number, the image capturing frame rate and the module refreshing frequency, judging whether the occurrence frequency of Flicker in the spectrogram is correct, and if not, indicating that the image capturing process has a frame missing phenomenon.
3. The method for remotely measuring Flicker value of a liquid crystal module as claimed in claim 1, wherein the method comprises the following steps of:
and acquiring Flicker period number in a time domain graph of the brightness based on the acquisition frame number, the image capturing frame rate and the module refreshing frequency, judging whether a lost frame exists in the image capturing process according to whether the Flicker period number in the time domain graph is correct, and if not, indicating that the lost frame phenomenon exists in the image capturing process.
4. The method for remotely measuring the Flicker value of the liquid crystal module according to claim 1, wherein when a frame loss occurs, the image obtained by current image capture is discarded, the display image of the liquid crystal module to be measured under a certain common electrode voltage is continuously image captured again, and the Flicker value under the common electrode voltage is obtained by the method according to claim 1, so as to ensure the accuracy of the Flicker value obtained by measurement.
5. A device for remotely measuring Flicker value of a liquid crystal module comprises:
the image capturing device is used for continuously capturing images of a display picture of the liquid crystal module to be tested under certain common electrode voltage at a fixed frame rate;
it is characterized by also comprising:
the calculation processing module is used for calculating the average brightness of each obtained image frame to obtain the time domain signal of the brightness, wherein the change relation of the average brightness of the liquid crystal module along with the collection frame number or time;
the Fourier transform module is used for carrying out fast Fourier transform on the time domain signal of the brightness to obtain a spectrogram of the brightness;
and the Flicker value calculating module is used for finding the peak amplitude corresponding to the frequency of the Flicker signal in the spectrogram and obtaining the Flicker value under the voltage of the common electrode according to the peak amplitude.
6. The device for remotely measuring the Flicker value of the liquid crystal module according to claim 5, further comprising a frame loss detection module for obtaining the occurrence frequency of Flicker in the spectrogram based on the acquisition frame number, the image capturing frame rate and the module refreshing frequency, judging whether the occurrence frequency of Flicker in the spectrogram is correct, and if not, prompting the occurrence of frame loss in the image capturing process.
7. The device for remotely measuring the Flicker value of the liquid crystal module according to claim 5, further comprising a lost frame detection module for obtaining the Flicker period number in the time domain graph of the brightness based on the acquisition frame number, the image acquisition frame rate and the module refresh frequency, judging whether a lost frame exists in the image acquisition process according to whether the Flicker period number in the time domain graph is correct, and if not, prompting that a lost frame phenomenon exists in the image acquisition process.
8. The device for remotely measuring the Flicker value of the liquid crystal module according to claim 6 or 7, wherein the Flicker value calculating module has signal interaction with the frame loss detecting module, discards the currently acquired image when the frame loss occurs, continuously captures the image of the display screen of the liquid crystal module to be measured under a certain common electrode voltage again, and obtains the Flicker value under the common electrode voltage to ensure the accuracy of the Flicker value obtained by measurement.
9. A system for remotely measuring Flicker value of a liquid crystal module comprises
The image capturing device is used for continuously capturing images of the liquid crystal module under certain common electrode voltage;
characterized by further comprising a processor, a memory, and a computer program stored in the memory and executable on the processor;
the computer program, when executed by a processor, controls an image capturing apparatus to implement the method according to any one of claims 1 to 4.
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