CN114355638A - Apparatus and method for quantitative evaluation of display black field Mura - Google Patents

Abstract

The invention discloses a quantitative evaluation device and method for the black field Mura of a display in the field of quantitative evaluation of the black field Mura of a display. The effective display area of the display collected by the imaging photometer is evenly divided into several analysis units; each analysis unit obtains the average brightness and chromaticity, and it is used as a unit array; several analysis units are compared pairwise to obtain The maximum total color difference is the result of the quantitative evaluation of the black field Mura of the display; the imaging luminance meter is used instead of the aiming point luminance meter for testing, and the display area is divided into several analysis units. The optical index difference between the regions is comprehensively evaluated, and the maximum quantitative value of the black field Mura is given.

Description

Apparatus and method for quantitative evaluation of display black field Mura

technical field

The present invention relates to the field of quantitative evaluation of display black field Mura, in particular, to a quantitative evaluation device and method for display black field Mura.

Background technique

Liquid crystal displays have been widely used in the military field, and they are usually used in a black background state. On military aircraft, there is a large vibration environment, and the vibration changes the cell thickness of the LCD screen, which in turn leads to an increase in brightness under the black background, that is, the black field Mura under the vibration environment. Mura reduces the contrast ratio of the displayed information, which affects the interpretation of the displayed information.

At present, military monitors all need to be reinforced through special processes to ensure their reliability. For liquid crystal displays, reinforcement means being subjected to external forces. The thickness of the LCD screen is controlled at the micron level. The stress generated by reinforcement is easily transmitted to the LCD screen in static and vibration environments, and unevenness appears on the LCD screen. Under external stress, the display shows different degrees of black Mura at different positions.

Mura needs to be continuously improved for black points, and it is a trade-off between reliability and display quality, and both are taken into account. At this time, in order to clearly point out the improvement direction, it is necessary to quantitatively evaluate the black field Mura to effectively give the improvement effect of the scheme.

Mura directly affects the contrast ratio of different positions of the display, he is a macro phenomenon. The contrast ratio is obtained indirectly through luminance measurement. The luminance is collected by measuring with no less than 500 pixels. For the Mura on the display, this measurement area is still small and does not match the Mura area that occurs in practical engineering applications.

Therefore, there is an urgent need to provide a quantitative evaluation device and method for the black field Mura of a display to solve the above technical problems.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a quantitative evaluation device and method for the black field Mura of a display. The imaging luminance meter is used instead of the aiming point luminance meter for testing, and the display area is divided into several analysis units. By analyzing the unit analysis area, different areas are analyzed. The difference of optical index between them is evaluated comprehensively and quantitatively, and the maximum quantitative value of black field Mura is given.

In order to achieve the above object, the present invention provides a quantitative evaluation device for the black field Mura of a display, the quantitative evaluation device includes a display and an imaging luminance meter for collecting optical parameters of the entire display area of the display.

Preferably, the optical parameters include luminance and chromaticity indicators of the display.

The present invention also provides a method for quantitatively evaluating the black field Mura of a display by using the above quantitative evaluation device. The imaging luminance meter is set directly in front of the display, and the entire display area of the display is collected at one time by the imaging luminance meter. luminance and chrominance indicators.

Preferably, the effective display area of the display collected by the imaging luminance meter is evenly divided into several analysis units.

Preferably, each of the analysis units obtains the average luminance and chromaticity as a unit array.

Preferably, a number of the analysis units are compared two by one to obtain the total color difference, and the largest total color difference is the result of the quantitative evaluation of the black field Mura of the display.

Preferably, the total color difference formula is as follows:

Among them, ΔE ^* is the total color difference, L ₁ and L ₂ are the luminance of area 1 and area 2, respectively, in cd/m ² , and are the CIE1976 color coordinates of area 1 and area 2, respectively.

According to the above technical solution, the imaging luminance meter collects the luminance and chromaticity of the display, then divides the collected area, then divides it into several parts, analyzes the luminance and chromaticity of each part, and finally calculates the two-by-two according to the total color difference formula. The total color difference of the partition, and its maximum value is the value of the black field Mura.

The invention can quantitatively give the quantitative evaluation result of the black field Mura, which is consistent with the current situation of engineering application. The black field Mura was evaluated quantitatively, which pointed out the direction for the improvement of black field Mura.

Other features and advantages of the present invention will be described in detail in the detailed description that follows.

Description of drawings

The accompanying drawings are used to provide a further understanding of the present invention, and constitute a part of the specification, and are used to explain the present invention together with the following specific embodiments, but do not constitute a limitation to the present invention. In the attached image:

1 is a schematic diagram of the positional relationship between a display of the present invention and an imaging luminance meter;

Fig. 2 is the data analysis schematic diagram of the present invention;

Fig. 3 is black field Mura quantitative evaluation grade table of the present invention;

FIG. 4 is a table of recommended analysis points for black and white spots of different display sizes according to the present invention.

Description of reference numerals

1- Monitor, 2- Imaging luminance meter.

Detailed ways

The specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only used to illustrate and explain the present invention, but not to limit the present invention.

The present invention provides a quantitative evaluation device for the black field Mura of a display. The quantitative evaluation device includes a display 1 and an imaging luminance meter 2 for collecting optical parameters of the entire display area of the display 1 .

In this embodiment, the optical parameters include luminance and chromaticity indices of the display 1 .

The present invention also provides a method for quantitatively evaluating the black field Mura of a display by using the above quantitative evaluation device. The imaging luminance meter 2 is set directly in front of the display 1, and the luminance and color of the entire display area of the display 1 are collected once by the imaging luminance meter 2. degree indicator.

In this embodiment, the effective display area of the display 1 collected by the imaging luminance meter 2 is evenly divided into several analysis units.

In the present embodiment, each analysis unit obtains the average luminance and chromaticity, which are used as a unit array (L, U', V').

In this embodiment, several analysis units are compared two by two to obtain the total color difference, and the largest total color difference is the result of the quantitative evaluation of the black field Mura of the display.

In this embodiment, the total color difference formula is as follows:

Among them, △E ^* is the total color difference, L ₁ and L ₂ are the luminance of area 1 and area 2 respectively, the unit is cd/m ² , U ₁ ′, V ₁ ′ and U ₂ ′, V ₂ ′ are respectively area 1 and CIE1976 color coordinates for region 2.

As shown in Figures 1 and 2, the imaging luminance meter 2 collects the luminance and chromaticity of the display 1, and then divides the collected area, then divides it into several parts, and analyzes the luminance and chromaticity of each part. The total chromatic aberration formula calculates the total chromatic aberration of the two partitions, and its maximum value is the value of the black field Mura.

Through statistical summary, Figure 3 gives the quantitative evaluation level of black field Mura. Through statistical analysis of different product sizes, Figure 4 shows the recommended evaluation points for different display sizes.

The invention can quantitatively give the quantitative evaluation result of the black field Mura, which is consistent with the current situation of engineering application. The black field Mura was evaluated quantitatively, which pointed out the direction for the improvement of black field Mura.

The preferred embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the specific details of the above-mentioned embodiments. Within the scope of the technical concept of the present invention, various simple modifications can be made to the technical solutions of the present invention, These simple modifications all belong to the protection scope of the present invention.

In addition, it should be noted that the specific technical features described in the above-mentioned specific embodiments can be combined in any suitable manner under the condition of no contradiction. In order to avoid unnecessary repetition, the present invention has The combination method will not be specified otherwise.

In addition, the various embodiments of the present invention can also be combined arbitrarily, as long as they do not violate the spirit of the present invention, they should also be regarded as the contents disclosed in the present invention.

Claims (7)

1. A quantitative evaluation device for display black field Mura, characterized in that the quantitative evaluation device comprises a display (1) and an imaging luminance meter (2) for collecting optical parameters of the entire display area of the display (1). 2. Quantitative evaluation device according to claim 1, characterized in that the optical parameters include luminance and chromaticity indices of the display (1). 3. A method for quantitatively evaluating display black field Mura using the quantitative evaluation device according to any one of claims 1-2, wherein the imaging luminance meter (2) is arranged on the display (2). 1) Right in front, and the luminance and chromaticity indicators of the entire display area of the display (1) are collected once by the imaging luminance meter (2). 4. The method according to claim 3, characterized in that, the effective display area of the display (1) collected by the imaging luminance meter (2) is evenly divided into several analysis units. 5. The method according to claim 4, characterized in that, each of the analysis units obtains the average luminance and chrominance as a unit array (L, U', V'). 6 . The method according to claim 5 , wherein a total color difference is obtained by comparing several of the analysis units two by one, and the largest total color difference is the result of the quantitative evaluation of the black field Mura of the display. 7 . 7. The method according to claim 6, wherein the total color difference formula is as follows:

Among them, △E* is the total color difference, L1 and L2 are the luminance of area 1 and area 2 respectively, the unit is cd/m ² , (U ₁ ′, V ₁ ′) and (U ₂ ′, V ₂ ′) are respectively Color coordinates of CIE1976 for area 1 and area 2.

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