CN114659754A - Display screen consistency detection method - Google Patents
Display screen consistency detection method Download PDFInfo
- Publication number
- CN114659754A CN114659754A CN202210213197.1A CN202210213197A CN114659754A CN 114659754 A CN114659754 A CN 114659754A CN 202210213197 A CN202210213197 A CN 202210213197A CN 114659754 A CN114659754 A CN 114659754A
- Authority
- CN
- China
- Prior art keywords
- display screen
- sub
- gray scale
- standard
- consistency
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 238000001514 detection method Methods 0.000 title claims abstract description 36
- 238000012360 testing method Methods 0.000 claims abstract description 74
- 238000012937 correction Methods 0.000 claims abstract description 49
- 230000003287 optical effect Effects 0.000 claims abstract description 35
- 238000000034 method Methods 0.000 claims abstract description 29
- 238000003384 imaging method Methods 0.000 claims description 78
- 239000011159 matrix material Substances 0.000 claims description 28
- 230000004907 flux Effects 0.000 claims description 5
- 238000000638 solvent extraction Methods 0.000 claims description 3
- 230000003750 conditioning effect Effects 0.000 claims description 2
- 238000002310 reflectometry Methods 0.000 claims description 2
- 238000009792 diffusion process Methods 0.000 description 10
- 238000012545 processing Methods 0.000 description 8
- 238000010586 diagram Methods 0.000 description 6
- 230000000694 effects Effects 0.000 description 6
- 230000008569 process Effects 0.000 description 4
- 230000000007 visual effect Effects 0.000 description 4
- 230000008901 benefit Effects 0.000 description 3
- 230000010354 integration Effects 0.000 description 2
- 230000002452 interceptive effect Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 239000002245 particle Substances 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 238000004088 simulation Methods 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 241001270131 Agaricus moelleri Species 0.000 description 1
- 230000001154 acute effect Effects 0.000 description 1
- 238000004458 analytical method Methods 0.000 description 1
- 230000005540 biological transmission Effects 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 238000013079 data visualisation Methods 0.000 description 1
- 238000005265 energy consumption Methods 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000005259 measurement Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012634 optical imaging Methods 0.000 description 1
- 230000004044 response Effects 0.000 description 1
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01M—TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR
- G01M11/00—Testing of optical apparatus; Testing structures by optical methods not otherwise provided for
- G01M11/02—Testing optical properties
-
- G—PHYSICS
- G09—EDUCATION; CRYPTOGRAPHY; DISPLAY; ADVERTISING; SEALS
- G09F—DISPLAYING; ADVERTISING; SIGNS; LABELS OR NAME-PLATES; SEALS
- G09F9/00—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements
- G09F9/30—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements
- G09F9/33—Indicating arrangements for variable information in which the information is built-up on a support by selection or combination of individual elements in which the desired character or characters are formed by combining individual elements being semiconductor devices, e.g. diodes
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Theoretical Computer Science (AREA)
- Chemical & Material Sciences (AREA)
- Analytical Chemistry (AREA)
- Controls And Circuits For Display Device (AREA)
Abstract
The invention provides a method for detecting consistency of a display screen. The method for detecting the consistency of the display screen comprises the following steps: building an optical module for illuminating ambient light of the display screen; acquiring image information of each sub display screen; obtaining the test gray scale of each sub display screen according to the image information of the sub display screens; calculating a correction coefficient of the ambient light at the position of each sub-display screen; weighting according to the test gray scale of the sub display screens and the correction coefficient to obtain the actual gray scale of each sub display screen; and fitting the actual gray scale of each sub-display screen, and judging whether the display screen meets the requirement of consistency. Therefore, the method for detecting the consistency of the display screen is reliable, and objective and accurate detection is carried out on the consistency of the black screen of the display screen.
Description
Technical Field
The invention relates to the field of display screens, in particular to a display screen consistency detection method.
Background
The LED display screen has the characteristics of high brightness, bright color, high luminous efficiency, high contrast, short response time, wide working temperature range, low energy consumption and the like, and is widely applied to stage display equipment, advertisement display equipment, data visualization display equipment and commercial display equipment.
Structurally, the LED display screen is formed by splicing a plurality of display panels into an independent box body, and then splicing a plurality of independent box bodies into a final complete screen body. Therefore, the display screen formed by splicing has the great advantages of being capable of being flexibly applied in various use scenes and free of display splicing. However, with this advantage, other negative problems may also be derived from the assembly structure, such as the problem of screen uniformity caused by the difference between the display panels due to the manufacturing process.
Aiming at the problem of consistency of black screens of LED display screens, at present, human eye subjective judgment is mainly adopted for operation, and human eye vision has difference, so that consistency detection results of the LED display screens are not reliable enough.
Disclosure of Invention
The invention aims to provide a reliable display screen consistency detection method for accurately detecting the black screen consistency of a display screen.
A method for detecting consistency of display screens, wherein the display screens comprise a plurality of sub display screens, and the method comprises the following steps:
building an optical module for illuminating ambient light of the display screen;
acquiring image information of each sub display screen;
obtaining the test gray scale of each sub display screen according to the image information of the sub display screens;
calculating a correction coefficient of the ambient light at the position of each sub-display screen, specifically: imaging to obtain the testing gray scale of the standard plate at the position of each sub display screen through the standard plate with the same gray scale value; selecting the test gray level of the standard plate positioned at the central position of the display screen as a standard gray level; the ratio of the test gray scale of the standard plate at each position to the standard gray scale is the correction coefficient at the position;
weighting according to the test gray scale of the sub display screen and the correction coefficient to obtain the actual gray scale of each sub display screen;
and fitting the actual gray scale of each sub-display screen, and judging whether the display screen meets the requirement of consistency.
In one embodiment, the standard board is a lamp board as large as the sub-display screens, and the step of calculating the correction coefficient of the ambient light at the position of each sub-display screen specifically includes:
the lamp panel is sequentially and correspondingly placed at each position of the sub display screen, and the test gray scale of the lamp panel is obtained through imaging respectively;
selecting the test gray level of the lamp panel corresponding to the sub-display screen at the central position of the display screen as a standard gray level;
and the ratio of the test gray scale of the lamp panel at each position to the standard gray scale is the correction coefficient at the position.
In one embodiment, the step of calculating the correction coefficient of the ambient light at the position of each sub-display screen includes:
covering the display screen with the standard color card, and correspondingly partitioning the standard color card according to the arrangement of the plurality of sub-display screens to form a plurality of sub-standard color cards;
imaging to obtain the test gray scale of the standard color card, and correspondingly obtaining the test gray scale of each sub-standard color card;
the testing gray scale of the sub-standard color card positioned at the central position of the color card to be standard is standard gray scale;
and the ratio of the test gray scale of the sub-standard color card at each position to the standard gray scale is the correction coefficient at the position.
In one embodiment, the step of fitting the actual gray scale of each sub-display screen and judging whether the display screen meets the requirement of consistency of the display screen specifically includes:
fitting the actual gray scale of each sub-display screen to form a fitting curve;
and when the standard deviation of the characteristic parameters of the fitting curve is less than or equal to 0.5, the display screen meets the requirement of consistency.
In one embodiment, the method specifically further includes:
obtaining the testing gray scale of each sub display screen according to the image information of the sub display screens, and constructing a testing gray scale matrix of each position of the display screen according to the testing gray scale of each position of the sub display screen and the position of the sub display screen;
calculating the correction coefficient of the ambient light at the position of each sub-display screen, and constructing a correction coefficient matrix at the position of each sub-display screen according to the correction coefficient of the ambient light at the position of each sub-display screen;
weighting the test gray matrix of each sub display screen and the correction coefficient matrix at the position of each sub display screen to obtain the actual gray matrix of each sub display screen;
and fitting according to the actual gray matrix of each sub-display screen to obtain a fitting curve, wherein when the standard deviation of the characteristic parameters of the fitting curve is less than or equal to 0.5, the display screens meet the requirement of consistency.
In one embodiment, the method further comprises the following steps:
adjusting an optical module to make the brightness and the intensity of the ambient light of the optical module uniform;
a conditioning imaging module comprising: making the exposure of the imaging module and the gray value in a linear relation; and adjusting the imaging area of the imaging module to enable the display screen to be positioned in the middle of the imaging area of the imaging module and account for 50% -70% of the imaging area.
In one embodiment, the optical module comprises two light sources, the brightness of the light sources is 1000 nits-20000 nits, and the luminous flux of the reflected light of the environment where the display screen is located is less than 10 lumens;
the two light sources are symmetrically arranged around the central normal of the display screen, the display screen receives two beams of incident light from the two light sources respectively, the incident angles of the two incident light beams are equal, and the distance between the two light sources is greater than the length of the display screen; the projection area of the optical module at the display screen is more than or equal to two thirds of the area of the display screen.
In one embodiment, the light source is a point light source, the optical module further includes a diffusion member disposed in front of the point light source, and light emitted from the point light source is diffused by the diffusion member and is uniformly projected toward the display screen.
In one embodiment, the diffuser is a reflection plate, the reflection surface of the reflection plate is a scattering surface, the color temperature of the reflection plate when the light beam of the point light source is scattered to the display screen through the scattering surface is 5500 kelvin-7000 kelvin, and the reflectivity of the reflection plate to the light emitted by the point light source is greater than 70%; the roughness of the reflecting plate satisfies: SCI-SCE is less than 0.5; wherein SCI includes a specular reflection mode and SCE does not include a specular reflection mode.
In one embodiment, the imaging module includes an imaging device and a guide rail, the imaging device is movably disposed on the guide rail to adjust an imaging position of the imaging device, the imaging device includes a zoom lens, and an aperture value of the zoom lens is greater than or equal to 5.
According to the display screen consistency detection method, the actual gray scale of each sub-display screen can be calculated through the acquired image information of each sub-display screen and the correction coefficient of the ambient light corresponding to the position of the sub-display screen. And (4) fitting the actual gray scale of each sub-display screen, and judging the consistency of the display screens according to the fitting result. Therefore, the consistency detection method of the display screen can automatically acquire the actual gray scale of each sub-display screen through a machine, evaluate the consistency of the black screen of the display screen according to objective actual gray scale data, and does not need artificial subjective observation as a judgment standard, so that the consistency detection method of the display screen is more reliable, and the detection result is more objective and accurate.
Drawings
Fig. 1 is a flowchart of a display screen consistency detection method according to an embodiment.
Fig. 2 is a spectrum distribution diagram of a light source of an optical module of a display screen black screen consistency detection method according to an embodiment.
Fig. 3 is a flowchart of a display screen consistency detection method according to another embodiment.
Fig. 4 is a schematic diagram of an optical module of a method for detecting consistency of a black screen of a display screen according to an embodiment.
Fig. 5 is a schematic diagram of an optical module of a display screen black screen consistency detection method according to another embodiment.
Fig. 6 is a schematic diagram of an optical module of a display screen black screen consistency detection method according to another embodiment.
Fig. 7 is a schematic structural view of the diffractive interference layer shown in fig. 6.
Fig. 8 is a schematic diagram of an optical module of a display screen black screen consistency detection method according to another embodiment.
Fig. 9 is a schematic structural view of the reflection plate shown in fig. 8.
Fig. 10 is a relationship between the exposure amount and the gradation value of the imaging apparatus.
FIG. 11 is a schematic diagram of a system for detecting consistency of a black screen of a display screen according to an embodiment.
Fig. 12 is a detailed flowchart of step S14.
The reference numerals are explained below: 11. a surface light source; 12. a point light source; 13. a diffuser; 131. a light diffusion layer; 132. a diffractive interference layer; 1321. a polarizer; 1322. a diffractive layer; 1323. an interference layer; 133 a reflective plate;
20. a display screen; 30. an imaging module; 31. an imaging device; 32. a guide rail; 40. an image processing module; 50. a correction module; 60. and a fitting module.
Detailed Description
Exemplary embodiments that embody features and advantages of the invention are described in detail below in the specification. It is to be understood that the invention is capable of other embodiments and that various changes in form and details may be made therein without departing from the scope of the invention and the description and drawings are to be regarded as illustrative in nature and not as restrictive.
The embodiment provides a display screen consistency detection method and a detection system. The display screen consistency detection method is used for detecting the black screen consistency of the display screen. The display screen consistency detection system is used for detecting the black screen consistency of the display screen according to the display screen consistency detection method.
The display screen includes a plurality of sub-display screens. And the plurality of sub-display screens are spliced to form a display screen with a large integral area. The display screen is generally rectangular, and the plurality of sub-display screens are arranged in a rectangular distribution. In order to facilitate the description of the sub-display screens at various positions, a plurality of sub-display screens of the display screen are labeled according to a matrix array. The display screen can be arranged in an m x n mode. For example, the display screen includes 15 sub-display screens, which are arranged in a3 × 5 arrangement. The sub-display screens are marked as A11, A12, A13, A14 and A15 from left to right and from top to bottom in sequence; a21, a22, a23, a24, a 25; a31, A32, A33, A34 and A35. It should be understood that the display screen is not limited to the 15 sub-display screens, nor to the distribution manner, and the specific composition manner of the display screen is not limited herein.
Referring to fig. 1, the method for detecting consistency of a display screen in this embodiment includes:
step S11, an optical module for illuminating ambient light of the display screen is built.
Step S12, acquiring image information of each of the sub display screens.
And step S13, obtaining the test gray scale of each sub display screen according to the image information of the sub display screen.
Step S14, calculating a correction coefficient of the ambient light at the position of each of the sub-display screens.
And step S15, weighting according to the test gray scale of the sub display screen and the correction coefficient to obtain the actual gray scale of each sub display screen.
And step S16, fitting the actual gray scale of each sub-display screen, and judging whether the display screen meets the requirement of consistency.
By the display screen consistency detection method, the actual gray scale of each sub-display screen can be calculated and obtained through the acquired image information of each sub-display screen and the correction coefficient of the ambient light corresponding to the position of the sub-display screen. And (4) fitting the actual gray scale of each sub-display screen, and judging the consistency of the display screens according to the fitting result. Therefore, the consistency detection method of the display screen can automatically obtain the actual gray scale of each sub-display screen through a machine, evaluate the consistency of the black screen of the display screen according to objective actual gray scale data, and does not need artificial subjective observation as a judgment standard, so that the consistency detection method of the display screen is more reliable, and the detection result is more objective and accurate.
Specifically, in this embodiment, the method for detecting the consistency of the display screen further includes, in step S10, determining the position of the display screen.
The display screen is fixedly arranged on the implementation site through a fixing device. The implementation site environment of the embodiment is a weak reflection environment, when a light source in the system is turned on, no strong reflection object exists except for the display screen to be detected, wherein the flux of the environment reflection light needs to be less than 10 lumens, and the environment reflection light is prevented from interfering the implementation of the system.
Step S11, an optical module for illuminating the ambient light of the display screen is built.
The display screen consistency detection of the present embodiment includes an optical module. The optical module is used for providing illuminating light for the display screen. The optical module comprises two light sources. The two light sources are symmetrically arranged about the central normal of the display screen. The two light sources respectively emit two beams of light, and the two beams of light are symmetrically projected to the central position of the display screen from the left side and the right side of the display screen respectively. The display screen receives two beams of incident light from the two light sources respectively, and the incident angles of the two beams of incident light are equal. Therefore, the light beams generated by the two light sources can be uniformly projected on the surface of the display screen, so that the influence of the ambient light on the surface of the display screen is reduced to the minimum, and the error of the test process caused by the uneven increase of the ambient light is avoided.
The distance between the two light sources is larger than the length of the display screen, so that a certain distance exists between the two side edges of the display screen and the light sources. The two light sources are respectively positioned at the two sides of the display screen, so that the situation that partial light of the light sources vertically enters the display screen to cause vertical reflection and form shadows on the surface of the display screen to influence the acquisition of imaging information of the display screen is avoided.
Referring to fig. 2, the spectrum of the light source is illustrated, and the brightness of the light source is 1000 nits to 20000 nits. And the luminous flux of the environment in which the display screen is located is less than 10 lumens. The field environment of the detection method is a weak reflection environment. When the light source of the system is lit, no strong reflecting objects must be present, except the display screen, where the ambient reflected light flux needs to be less than 10 lumens to prevent the ambient reflected light from interfering with the system implementation.
In this embodiment, the light source may be a surface light source 11 or a point light source 12.
Referring to fig. 3, the method for detecting the consistency of the display screen further includes step S112: and adjusting the optical module to make the brightness and the intensity of the ambient light of the optical module uniform.
Referring to fig. 4, when the light source is a surface light source 11, the two surface light sources 11 are symmetrically disposed about a center normal of the display panel. The two surface light sources 11 emit two light beams, and the two light beams are projected symmetrically from the left and right sides of the display screen 20 to the central position of the display screen 20. The display panel 20 receives two incident lights from two light sources respectively, and the incident angles of the two incident lights are equal. Therefore, the light beams generated by the two-sided light source 11 can be uniformly projected on the surface of the display screen 20, so that the influence of the ambient light on the surface of the display screen 20 is reduced to the minimum, and the error of the test process caused by the uneven ambient light is avoided.
The projection area of the surface light source 11 at the display screen 20 is larger than two thirds of the display screen area.
And the horizontal distances between the two surface light sources 11 and the two side edges of the display screen 20 are S1 and S2 respectively, and satisfy the following conditions: s2 > 0 in S1. The distance between the two surface light sources 11 is greater than the length of the display screen. A line connecting the center of the surface light source 11 and the center of the display panel makes an angle θ 1 and θ 2 with the normal line of the center, and θ 1 is equal to θ 2. An angle between a line connecting the center of the surface light source 11 and the center of the display screen 20 and the surface of the surface light source 11 is α 1, α 2, and satisfies 0 ° α 1 ≦ α 2 ≦ 90 °. The light source of the optical module 10 is arranged in such a way that the light on the surface of the display screen 20 is uniformly distributed.
Referring to fig. 3, when the light source is the point light source 12, a projection area of the point light source 12 of the optical module 10 on the display screen 20 is smaller than two thirds of an area of the display screen 20, so as to ensure that light rays that the point light source 12 can project on the display screen 20 are uniform.
And the horizontal distances between the two point light sources 12 and the two side edges of the display screen 20 are S1 and S2 respectively, and satisfy: s2 > 0 in S1. I.e., the distance between the two point light sources 12 is greater than the length of the display screen 20. A line connecting the center of the point light source 12 and the center of the display panel 20 forms an angle θ 1 and θ 2 with the center normal of the display panel 20, and θ 1 is equal to θ 2. An included angle between a line connecting the center of the point light source 12 and the center of the display screen 20 and the surface of the point light source 12 is α 1, α 2, and satisfies 0 ° α 1 ≦ α 2 ≦ 90 °. The light source of the optical module 10 is arranged in a manner that light on the surface of the display screen 20 is uniformly distributed.
Referring to fig. 5, when the light source is a point light source 12, the optical module 10 further includes a diffuser 13 disposed in front of the point light source 12. The light emitted from the point light source 12 is diffused by the diffusion member 13 and is uniformly projected toward the display screen 20. The light that point light source 12 sent sees through diffusion piece 13 increase light-emitting angle and area simulation environment light direction, through adjustment point light source luminance simulation environment light brightness, and it is more even that the light is laid, and the visual effect of display screen 20 is more close with the condition under the ambient light irradiation.
The diffuser 13 may be a light diffusing layer 131. The light diffusion layer 131 contains scattering particles. When the light emitted from the point light source 12 passes through the light diffusion layer, the light is scattered by the scattering particles, so that the light emitting angle and area of the light can be increased. Two light diffusion layers 131 are disposed between the point light source 12 and the display panel 20, and are in a symmetrical relationship with respect to a center normal of the display panel 20. After the light beam is diffused by the light diffusion layer 131, the projection area of the light beam at the display screen 20 is greater than or equal to two thirds of the area of the display screen 20. And the center normal of the light diffusion layer 131 coincides with the optical axis of the point light source 12.
Referring to fig. 6 and 7, the diffuser 13 may also be a diffractive interference layer 132. The diffractive interference layer 132 includes a polarizer 1321, a diffractive layer 1322, and an interference layer 1323 stacked in this order. Wherein the polarizer 1321 is located on the side of the diffractive interference layer 132 close to the point light source 12. The polarizer 1321 converts the light emitted from the point light source 12 into polarized light, and then the polarized light undergoes optical diffraction interference through the diffraction layer 1322 and the interference layer 1323 to form a large-area light mass to be irradiated on the display screen 20. Two diffractive interference layers 132 are disposed between the point light source 12 and the display screen 20, and the two diffractive interference layers 132 are symmetrical with respect to a center normal of the display screen 20. After the light beams are diffused by the diffraction interference layer 132, the projection area of the light rays at the display screen 20 is more than or equal to two thirds of the area of the display screen 20. And the center normal of the diffractive interference layer 132 coincides with the optical axis of the point light source 12.
Referring to fig. 8 and 9, the diffuser 13 may also be a reflector 133. The point light source 12 and the display screen 20 are disposed on the same side with respect to the imaging module 30 and behind the display screen 20, and light from the point light source 12 is irradiated to the reflection plate 133. The reflecting surface of the reflecting plate 133 is a scattering surface. The light beam of the point light source 12 is reflected to the display screen 20 via the scattering surface.
The color temperature of the reflection plate 133 is 5500 kelvin-7000 kelvin. The reflection plate 133 has a reflectance of more than 70% with respect to the light emitted from the point light source 12, and the reflectance of the light of each wavelength band is the same. After the light beam is reflected and diffused by the reflecting plate 133, the projection area of the light beam at the display screen 20 is greater than or equal to two thirds of the area of the display screen 20. The roughness of the reflection plate 133 satisfies: SCI-SCE is less than 0.5; wherein SCI is a Specular reflection included (Specular Component included) mode, and SCE is a Specular reflection excluded (Specular Component included) mode.
The two reflective plates 133 are both oriented toward the display screen 20 and are symmetrical with respect to the center normal of the display screen 20. The horizontal distance between the two reflective plates 133 and the display screen 20 is S1 and S2, and S1 is satisfied as S2 > 0. The center of the reflection plate 133 is connected with the center of the display screen 20, and forms an angle θ 1 and θ 2 with the normal of the center of the display screen 20, and θ 1 is equal to θ 2. A line connecting the center of the reflection plate 133 and the center of the display panel 20 makes an angle α 1, α 2 with the surface of the reflection plate 133, and α 1 — α 2 is 90 °. That is, the light from the point light source 12 is scattered by the reflective plate 133 to form scattered light, and the scattered light is projected on the display screen 20 in a direction perpendicular to the exit direction of the reflective plate 133.
The light receiving condition of the display screen 20 in the use occasion is simulated through the optical module 10, so that the display screen 20 receives light uniformly, and the visual observation effect and the equipment imaging effect of the display screen 20 in the evaluation environment are consistent with those of the display screen 20 in the use occasion.
The display screen consistency detection system of the present embodiment includes an imaging module 30. The imaging module 30 is disposed in front of the display screen 20. The imaging module 30 is used for imaging and acquiring image information.
The method for detecting consistency of a display screen according to this embodiment further includes step S114: the adjusting imaging module 30 specifically includes: the exposure and the gray value of the imaging module are in a linear relation, and the imaging area of the imaging module is adjusted, so that the display screen is positioned in the middle of the imaging area of the imaging module and accounts for 50% -70% of the imaging area.
Referring to fig. 4, the imaging module 30 includes an imaging device 31 and a guide rail 32. The imaging device 31 is movably provided on the guide rail 32 to adjust the position of the imaging device 31. The exposure of the imaging module is the exposure of the imaging device 31, and the imaging area of the imaging module is the imaging area of the imaging device 31.
The imaging device 31 may adopt a Charge Coupled Device (CCD) camera, and the lens obtains the required imaging quality by adjusting the focal length, aperture value, integration time, ISO sensitivity of the CCD camera. The imaging device 31 includes a zoom lens. The aperture value of the zoom lens is 5 or more.
As shown in fig. 10, the photoelectric conversion characteristic of the photosensitive material used in the photosensitive layer of the camera core structure has a nonlinear relationship D (f) (H) (a to D) between the exposure amount H and the gray value D, and in order to ensure that the relative gray scale of the lamp panel can be truly displayed when the display screen is black during the shooting process of the device, the exposure amount H and the gray value D are controlled to have a linear relationship (B to C), specifically, the exposure amount satisfies the formula:
H＝B×(π/4)×[T/(F^2)]×τ；
wherein, H is the exposure, B is the brightness of the target object, T is the exposure time, F is the camera F-number, and tau is the optical transmission coefficient of the lens.
Because all optical lenses can generate a vignetting effect, whether the lenses can generate the vignetting or not depends on the type of the lenses and the setting of the diaphragm of imaging equipment, under a large diaphragm, light rays entering the lenses can be blocked by the lens barrel to a certain extent, light rays transmitted at an acute angle can be reflected by the lenses, the edges of obtained images are darkened, and in order to enable the final imaging and visual observation results to be close to improve the imaging fidelity, the vignetting effect needs to be avoided as much as possible, a zoom lens is selected, and the low diaphragm value is more than or equal to 5.
Focusing the imaging device 31, the display screen 20 needs to be arranged in the middle of the imaging area of the imaging device and accounts for 50% -70% of the whole imaging area, and the final imaging effect needs to be consistent with the effect of human eyes on subjective screen observation
In step S12, image information of each sub display screen is acquired.
The imaging device 31 obtains the required imaging quality through adjusting the focal length, the aperture value, the integration time and the ISO sensitivity of the CCD camera. The imaging module is used for imaging and acquiring image information of each sub display screen.
And step S13, obtaining the test gray scale of each sub display screen according to the image information of the sub display screen.
Referring to fig. 11, the display screen consistency detection system further includes an image processing module 40. The image processing module 40 is configured to obtain a test gray scale of the sub-display according to the image information of the sub-display.
The image processing module 40 processes the images of the sub-display screens captured by the imaging module 30, quantizes the visual observation result into a gray value to represent the blackness difference between the sub-display screens, and can use matlab, Labview, Python, C + + or other tools as the implementation medium of the image processing algorithm.
Step S13, specifically, obtaining the test gray scale of each sub-display screen according to the image information of the sub-display screen, and constructing the test gray scale matrix of each position of the display screen according to the test gray scale of the sub-display screen at each position and the position of the sub-display screen. The test gray matrix C of each sub-display is:
and Cmn is the test gray scale of the sub display screen at the corresponding position.
In step S14, a correction coefficient of the ambient light at the position of each sub-display is calculated.
The display screen consistency detection system of the present embodiment further includes a correction module 50. The correction module 50 is used for calculating a correction coefficient of the ambient light at the position of each sub-display.
Specifically, the specific steps of calculating the correction coefficient are as follows:
referring to fig. 12, in step S141, the standard board with the same gray value is imaged at the position of each sub-display screen to obtain the test gray of the standard board.
Specifically, in this embodiment: the display screen consistency detection of the embodiment further comprises one or more standard plates with the same gray value. The standard plate is used for measuring the correction coefficient of the position of each sub-display screen. The gray scale requirements of the standard plate are consistent.
Specifically, the test gray scale of the standard plate at the position of each sub-display screen is obtained, and a test gray scale matrix of the standard plate at each position of the display screen is constructed according to each test gray scale and the position of the test gray scale. The test gray matrix B of the standard plate is:
and Bmn is the test gray level of the standard board corresponding to the position of each sub-display screen.
In one embodiment, the standard board may be a lamp board as large as the sub-display. Step S141 is specifically: and correspondingly placing the lamp panel at each position of the sub-display screen in sequence, and respectively imaging to obtain the test gray scale of the lamp panel. The test gray scale of each lamp panel corresponds to the test gray scale of the standard panel at the position of each sub display screen. Because the lamp plate is same lamp plate, can not be because of the self reason production error of lamp plate. Therefore, the lamp panel is sequentially placed in front of each sub-display screen, and the test gray scale at the corresponding position is obtained through imaging, and corresponds to Bmn in the test gray scale matrix B.
In another embodiment, the standard board may be a standard color card having a size equal to that of the display screen. The standard color card is arranged in front of the display screen, and because the gray scales of all the parts of the standard color card are uniform, the standard plate is integrally imaged, and the test gray scale of the position of each sub-display screen corresponding to the standard color card can be obtained. Step S141 may specifically include: and covering the display screen with the standard color card, and correspondingly partitioning the standard color card according to the arrangement of the plurality of sub-display screens to form a plurality of sub-standard color cards. And imaging the standard plate to obtain the test gray scale of the standard color card, and correspondingly obtaining the test gray scale of each sub-standard color card according to the dividing mode of the standard color card and the sub-standard color card. Therefore, the test gray of each sub-standard color card and the test gray of the corresponding standard board at the position of each sub-display correspond to Bmn in the test gray matrix B.
Therefore, the specific form of the standard plate is not limited, as long as the measured gray scale at the position of the sub display screen can be measured more accurately.
And S142, selecting the test gray scale of the standard plate positioned at the central position of the display screen as the standard gray scale.
The sub-display positioned at the central position of the display may be positioned as a central sub-display according to a matrix arrangement of sub-displays of the display. The central sub-display screen is located in the middle of the display screen, the ambient light can be uniformly projected onto the central sub-display screen, and the test gray scale of the central sub-display screen is minimally affected by position factors, light factors and the like, so that the test gray scale corresponding to the standard plate at the position of the central sub-display screen is selected as the standard gray scale.
Regarding the selection of the central sub-display screen, the specific steps are as follows: for the sub-panels arranged m x n, the central sub-panel, i.e. located in the matrix, is labeled a
Sub-display at a location. Wherein, the first and the second end of the pipe are connected with each other,
in (2)]As a rounding function, i.e. pair
And (6) taking the whole. The standard gray D is B in the measured gray matrix B
The value of (c).
For example, when the sub-panels of the display panel are arranged in 3 × 5. The sub-display in the center of the display is the label a23 tile sub-display. The standard gray scale D is the value of B23. As another example, when the sub-panels of the display are in a 4 x 6 arrangement. The sub-display screen located in the center of the display screen is marked as a23 sub-display screen, and the standard gray D is the value of B23.
For the different implementation modes of the standard board, when the standard board is a lamp board with a size equal to that of the sub-display screen, the standard gray scale is the measurement gray scale of the lamp board when the lamp board is located at the position of the central sub-display screen. When the standard panel is a standard color card as large as the display screen, the standard gray scale is the measured gray scale of the sub-standard panel located at the position of the central sub-display screen.
In step S143, the ratio of the test gray scale to the standard gray scale of the standard board at each position is the correction coefficient at that position.
The calibration module 50 compares the sub-display screens at other positions with the standard gray scale, so as to evaluate the influence of the ambient light at the position of each sub-display screen, and correspondingly form a calibration coefficient J of the ambient light at the position, that is: j equals B/D.
Calculating a correction coefficient of the ambient light at the position of each sub-display, and constructing a correction coefficient matrix Jmn at the position of each sub-display according to the correction coefficient of the ambient light at the position of each sub-display, wherein the correction coefficient matrix Jmn is Bmn/D; specifically, the method comprises the following steps:
wherein Jmn is the correction coefficient at the position of each sub-display screen.
For the different embodiments of the standard board, when the standard board is a large lamp panel such as a sub display screen, the ratio of the test gray level of the lamp panel at each position to the standard gray level is the correction coefficient at the position. When the standard plate is a standard color card with the size equal to that of the display screen, the ratio of the test gray scale to the standard gray scale of the sub-standard color card at each position is the correction coefficient at the position.
Referring to fig. 1 again, in step S15, the actual gray scale of each sub-display is obtained according to the test gray scale and the calibration coefficient of the sub-display. That is, the product of the test gray scale of the sub-display and the correction coefficient at the position of the sub-display is the actual gray scale of the sub-display.
The correction module 50 is further configured to obtain an actual gray scale of each sub-display screen according to the test gray scale of each sub-display screen and the correction coefficient at the position of the sub-display screen.
Specifically, weighting the test gray matrix of each sub-display screen with the correction coefficient matrix at the position of each sub-display screen to obtain the actual gray matrix S of each sub-display screen. The method specifically comprises the following steps:
and multiplying the test gray level Cmn of the sub display screen by the correction coefficient Jmn at the position of the sub display screen correspondingly to obtain the actual gray level Smn of the sub display screen.
And step S16, fitting the actual gray scale of each sub-display screen, and judging whether the display screen meets the consistency requirement of the display screen.
The display screen consistency detection system of the present embodiment further includes a fitting module 60. The fitting module 60 is configured to fit the actual gray levels of the sub-display screens, and judge whether the display screens meet the requirement of consistency.
The image processing module 40, the correcting module 50, and the fitting module 60 may be integrated into a whole machine or a control chip, or may be 2 or 3 independent structures. The specific forms of the image processing module 40, the correction module 50, and the fitting module 60 are not limited herein.
Step S16 specifically includes: the fitting module 60 can fit the actual gray levels of the sub-display screens to form a fitting curve. Namely fitting according to the actual gray matrix S to obtain a fitting curve.
The fitting module 60 calculates the standard deviation of the characteristic parameters of the fitted curve, and when the standard deviation of the characteristic parameters of the fitted curve is less than or equal to 0.5, the display screen meets the requirement of consistency.
Specifically, in the present embodiment, the fitting algorithm for the actual gray scale of each sub-display may be a fitting algorithm such as gaussian fitting or euclidean fitting.
According to the method and the system for detecting the consistency of the display screen, the optical imaging equipment can be used for shooting the black screen image of the display screen, the image processing and analysis are carried out, and finally the gray value of a single sub-display screen in the screen body of the display screen is obtained to replace the subjective judgment of human eyes to carry out the characterization of the consistency of the black screen of the display screen. Therefore, the detection result of the consistency of the display screen by the detection method and the detection system for the consistency of the display screen is objective and accurate; moreover, labor force can be saved, and the method is convenient to implement and popularize.
While the present invention has been described with reference to several exemplary embodiments, it is understood that the terminology used is intended to be in the nature of words of description and illustration, rather than of limitation. As the present invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, it should also be understood that the above-described embodiments are not limited by any of the details of the foregoing description, but rather should be construed broadly within its spirit and scope as defined in the appended claims, and therefore all changes and modifications that fall within the meets and bounds of the claims, or equivalences of such meets and bounds are therefore intended to be embraced by the appended claims.
Claims (10)
1. A method for detecting consistency of display screens, wherein each display screen comprises a plurality of sub display screens, is characterized by comprising the following steps:
building an optical module for illuminating ambient light of the display screen;
acquiring image information of each sub display screen;
obtaining the test gray scale of each sub display screen according to the image information of the sub display screens;
calculating a correction coefficient of the ambient light at the position of each sub-display screen, specifically: imaging to obtain the testing gray scale of the standard plate at the position of each sub display screen through the standard plate with the same gray scale value; selecting the test gray level of the standard plate positioned at the central position of the display screen as a standard gray level; the ratio of the test gray scale of the standard plate at each position to the standard gray scale is the correction coefficient at the position;
weighting according to the test gray scale of the sub display screen and the correction coefficient to obtain the actual gray scale of each sub display screen;
and fitting the actual gray scale of each sub-display screen, and judging whether the display screens meet the requirement of consistency.
2. The method according to claim 1, wherein the standard board is a lamp board that is as large as the sub-display screens, and the step of calculating the correction coefficient of the ambient light at the position of each sub-display screen specifically includes:
the lamp panel is sequentially and correspondingly placed at each position of the sub display screen, and the test gray scale of the lamp panel is obtained through imaging respectively;
selecting the test gray level of the lamp panel corresponding to the sub-display screen at the central position of the display screen as a standard gray level;
and the ratio of the test gray scale of the lamp panel at each position to the standard gray scale is the correction coefficient at the position.
3. The method according to claim 1, wherein the standard board is a standard color chart having a size equal to that of the display screen, and the step of calculating the correction coefficient of the ambient light at the position of each sub-display screen specifically includes:
covering the display screen with the standard color card, and correspondingly partitioning the standard color card according to the arrangement of the plurality of sub-display screens to form a plurality of sub-standard color cards;
imaging to obtain the test gray level of the standard color card, and correspondingly obtaining the test gray level of each sub-standard color card;
the testing gray scale of the sub-standard color card positioned at the central position of the color card to be standard is standard gray scale;
and the ratio of the test gray scale of the sub-standard color card at each position to the standard gray scale is the correction coefficient at the position.
4. The method for detecting the consistency of the display screens according to claim 1, wherein the step of fitting the actual gray scale of each sub-display screen and judging whether the display screen meets the consistency requirement of the display screen specifically comprises the following steps:
fitting the actual gray scale of each sub-display screen to form a fitting curve;
and when the standard deviation of the characteristic parameters of the fitting curve is less than or equal to 0.5, the display screen meets the requirement of consistency.
5. The method for detecting the consistency of the display screen according to claim 1, further comprising the following steps:
obtaining the testing gray scale of each sub display screen according to the image information of the sub display screens, and constructing a testing gray scale matrix of each position of the display screen according to the testing gray scale of each position of the sub display screen and the position of the sub display screen;
calculating the correction coefficient of the ambient light at the position of each sub-display screen, and constructing a correction coefficient matrix at the position of each sub-display screen according to the correction coefficient of the ambient light at the position of each sub-display screen;
weighting the test gray matrix of each sub display screen and the correction coefficient matrix at the position of each sub display screen to obtain the actual gray matrix of each sub display screen;
and fitting according to the actual gray matrix of each sub-display screen to obtain a fitting curve, wherein when the standard deviation of the characteristic parameters of the fitting curve is less than or equal to 0.5, the display screen meets the requirement of consistency.
6. The display screen consistency detection method according to claim 1, further comprising the steps of:
adjusting an optical module to make the brightness and the intensity of the ambient light of the optical module uniform;
a conditioning imaging module comprising: making the exposure of the imaging module and the gray value in a linear relation; and adjusting the imaging area of the imaging module to enable the display screen to be positioned in the middle of the imaging area of the imaging module and account for 50% -70% of the imaging area.
7. The method for detecting the consistency of the display screen according to claim 1, wherein the optical module comprises two light sources, the brightness of the light sources is 1000 nits to 20000 nits, and the luminous flux of the environment where the display screen is located is less than 10 lumens;
the two light sources are symmetrically arranged around the central normal of the display screen, the display screen receives two beams of incident light from the two light sources respectively, the incident angles of the two incident light beams are equal, and the distance between the two light sources is greater than the length of the display screen; the projection area of the optical module at the display screen is more than or equal to two thirds of the area of the display screen.
8. The method for detecting the uniformity of a display screen according to claim 7, wherein the light source is a point light source, the optical module further comprises a diffuser disposed in front of the point light source, and light emitted from the point light source is diffused by the diffuser and is uniformly projected toward the display screen.
9. The method according to claim 8, wherein the diffuser is a reflector, the reflective surface of the reflector is a scattering surface, the color temperature of the light beam from the point light source scattered by the scattering surface to the reflector of the display screen is 5500 kelvin-7000 kelvin, and the reflectivity of the reflector to the light beam from the point light source is greater than 70%; the roughness of the reflecting plate satisfies the following conditions: SCI-SCE is less than 0.5; wherein SCI includes a specular reflection mode and SCE does not include a specular reflection mode.
10. The method according to claim 6, wherein the imaging module includes an imaging device and a guide rail, the imaging device is movably disposed on the guide rail to adjust an imaging position of the imaging device, the imaging device includes a zoom lens, and an aperture value of the zoom lens is greater than or equal to 5.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210213197.1A CN114659754A (en) | 2022-03-04 | 2022-03-04 | Display screen consistency detection method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210213197.1A CN114659754A (en) | 2022-03-04 | 2022-03-04 | Display screen consistency detection method |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN114659754A true CN114659754A (en) | 2022-06-24 |
Family
ID=82027972
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202210213197.1A Pending CN114659754A (en) | 2022-03-04 | 2022-03-04 | Display screen consistency detection method |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN114659754A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116698376A (en) * | 2023-08-08 | 2023-09-05 | 徐州隆运好信息科技有限公司 | Intelligent testing method for quality uniformity of outdoor spliced display screen based on scene simulation |
| CN116754069A (en) * | 2023-08-23 | 2023-09-15 | 荣耀终端有限公司 | Calibration data testing method, electronic device, testing equipment and storage medium |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004070228A (en) * | 2002-08-09 | 2004-03-04 | Shima Seiki Mfg Ltd | Display device and design device each having ambient light source correction function, method of designing, and colorimeter unit |
| CN102967443A (en) * | 2012-10-26 | 2013-03-13 | 京东方科技集团股份有限公司 | Transparent display device testing method and device |
| CN104296971A (en) * | 2014-10-22 | 2015-01-21 | 中国电子科技集团公司第四十一研究所 | Display contrast calibration method and device under high luminance environment |
| CN204855669U (en) * | 2015-07-30 | 2015-12-09 | 中国电子科技集团公司第四十一研究所 | Machine carries display photoelectric parameter automatic measuring device |
| CN115018766A (en) * | 2022-04-29 | 2022-09-06 | 杭州福斯特应用材料股份有限公司 | Detection method for film material evenness |
-
2022
- 2022-03-04 CN CN202210213197.1A patent/CN114659754A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2004070228A (en) * | 2002-08-09 | 2004-03-04 | Shima Seiki Mfg Ltd | Display device and design device each having ambient light source correction function, method of designing, and colorimeter unit |
| CN102967443A (en) * | 2012-10-26 | 2013-03-13 | 京东方科技集团股份有限公司 | Transparent display device testing method and device |
| CN104296971A (en) * | 2014-10-22 | 2015-01-21 | 中国电子科技集团公司第四十一研究所 | Display contrast calibration method and device under high luminance environment |
| CN204855669U (en) * | 2015-07-30 | 2015-12-09 | 中国电子科技集团公司第四十一研究所 | Machine carries display photoelectric parameter automatic measuring device |
| CN115018766A (en) * | 2022-04-29 | 2022-09-06 | 杭州福斯特应用材料股份有限公司 | Detection method for film material evenness |
Non-Patent Citations (1)
| Title |
|---|
| 张懿: "大屏幕投影拼接系统的色均匀矫正", 《中国优秀博硕士学位论文全文数据库 (硕士)信息科技辑》, no. 05, 15 May 2006 (2006-05-15), pages 27 - 33 * |
Cited By (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116698376A (en) * | 2023-08-08 | 2023-09-05 | 徐州隆运好信息科技有限公司 | Intelligent testing method for quality uniformity of outdoor spliced display screen based on scene simulation |
| CN116698376B (en) * | 2023-08-08 | 2023-11-07 | 徐州隆运好信息科技有限公司 | Intelligent testing method for quality uniformity of outdoor spliced display screen based on scene simulation |
| CN116754069A (en) * | 2023-08-23 | 2023-09-15 | 荣耀终端有限公司 | Calibration data testing method, electronic device, testing equipment and storage medium |
| CN116754069B (en) * | 2023-08-23 | 2023-11-10 | 荣耀终端有限公司 | Calibration data testing method, electronic device, testing equipment and storage medium |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN114659754A (en) | Display screen consistency detection method | |
| CN101377918B (en) | Electronic display screen system, method and system for correcting electronic display screen brightness | |
| CN107917905B (en) | Ratio type luminosity analysis device based on intelligent terminal and detection method thereof | |
| US20110157242A1 (en) | Display device incorporating backlight plate composed of edge-lit light guides and method of unifying light emission from same | |
| CN201218753Y (en) | Brightness measurement apparatus | |
| KR101630596B1 (en) | Photographing apparatus for bottom of car and operating method thereof | |
| EP3270120A1 (en) | Measurement method, measurement device, and program | |
| KR100397080B1 (en) | Flat Display Inspection System | |
| CN101076720B (en) | Apparatus for inspecting backlight unit | |
| JP2672563B2 (en) | Device for measuring display screen contrast as a function of viewing direction. | |
| CN111638042B (en) | DLP optical characteristic test analysis method | |
| Chrzanowski | Review of night vision metrology | |
| Beuckels et al. | Contrast gloss evaluation by use of a camera-based gloss meter | |
| US20020105638A1 (en) | Apparatus for inspecting display panel and method for inspecting the same | |
| CN102645321B (en) | Active near-infrared camera operating distance evaluation system based equivalent illumination | |
| CN109632269A (en) | Method based on image grayscale infomation detection diffractive-optical element performance | |
| CN211783857U (en) | Spatial distribution optical measuring device | |
| Sayanca et al. | Indirect light intensity distribution measurement using image merging | |
| CN102661851B (en) | Active near infrared camera operating distance evaluation method based on equivalent illumination | |
| CN112161956A (en) | Lens detection method, device and system and readable storage medium | |
| WO2019200936A1 (en) | Detection method for spatial light modulator | |
| CN111795800A (en) | Visual speckle contrast measuring device and method | |
| Mou et al. | 16.1: Invited Paper: Measurement of Perceived Pixel Luminance of Large LED Displays | |
| CN110823916A (en) | Display panel inspection apparatus | |
| Rykowski et al. | 9.3: The Use of an Imaging Sphere for High‐Throughput Measurements of Display Performance—Technical Challenges and Mathematical Solutions |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination |