Light source evaluation and selection method suitable for laser display

Abstract

The invention discloses a light source evaluation and selection method suitable for laser display, relates to the technical field of laser display, and aims to solve the problems that in the prior art, when speckle suppression is carried out by using multiple light source schemes in laser display, the color gamut expression of a display system is influenced, and the color gamut and brightness of the system are possibly sharply reduced. Therefore, the laser display advantage is lost; according to the invention, a corresponding speckle contrast expression is obtained through a light source spectrum; chromaticity coordinates corresponding to the light source types are obtained; judging whether light source brightness limitation exists or not; if yes, calculating a three-dimensional color gamut volume ratio according to the corresponding chromaticity coordinates; if not, calculating a plane color gamut coverage rate ratio according to the corresponding chromaticity coordinates; obtaining an evaluation factor according to the color gamut ratio and the speckle contrast expression; selecting and evaluating corresponding evaluation factors; the speckle suppression and color gamut performance of the light source can be comprehensively evaluated, the method is suitable for optimal configuration selection in different scenes, and the light source selectivity in laser display is greatly improved.

Description

Technical Field

[0001] The invention belongs to the field of optoelectronic display, relates to laser display technology, and specifically is a method for evaluating and selecting a light source in laser display. Background Art

[0002] Laser display has become one of the latest generation of display technologies. It is widely used in various scenarios due to its advantages such as large color gamut, high brightness and long life. Although narrow-spectrum laser light sources bring the advantage of large color gamut, their high coherence also brings laser speckle phenomenon, which will seriously affect the display quality and make people uncomfortable. Therefore, color management and speckle phenomenon research are key contents in laser display. Among them, color management research aims to give full play to the large color gamut advantage of laser display, while the main purpose of speckle phenomenon research is to suppress speckle to a level that cannot be perceived by the human eye. The light source in laser display will directly affect the color gamut performance and speckle severity of the display system, so it is very important.

[0003] In the prior art, speckle suppression elements are usually used for speckle suppression in laser display. In addition, there are also light source solutions of wide-spectrum laser, multi-wavelength laser hybrid, laser and LED hybrid, and laser + phosphor. Among them, the proposal of the scheme of speckle suppression through light source can bring about the speckle suppression effect, but at the same time it will directly affect the color gamut performance of the display system, resulting in a sharp drop in the system color gamut and brightness, thereby losing the advantages of laser display.

[0004] The present invention provides a method for evaluating and selecting a light source suitable for laser display to solve the above technical problems. Summary of the invention

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art; to this end, the present invention proposes a method for evaluating and selecting a light source suitable for laser display, which is used to solve the technical problem that when the prior art uses a variety of light source solutions such as wide-spectrum laser, multi-wavelength laser hybrid, laser and LED hybrid, and laser + phosphor in laser display, although it can bring about a speckle suppression effect, it will directly affect the color gamut performance of the display system, resulting in a sharp drop in the system color gamut and brightness, thereby losing the advantages of laser display.

[0006] To achieve the above object, a first aspect of the present invention provides a method for evaluating and selecting a light source for laser display, comprising:

[0007] S1: Obtain an input light source type from a database, and obtain a corresponding speckle contrast expression through the light source spectrum; wherein the light source types include: a pure laser light source, and a mixed light of a laser and an incoherent light source;

[0008] S2: Obtain the chromaticity coordinates of the corresponding light source type;

[0009] S3: Determine whether there is a light source brightness limitation; if yes, calculate the three-dimensional color gamut volume ratio according to the corresponding chromaticity coordinates; if no, calculate the plane color gamut coverage ratio according to the corresponding chromaticity coordinates;

[0010] S4: Retrieve the corresponding color gamut ratio; obtain the evaluation factor according to the color gamut ratio and the speckle contrast expression; select and evaluate the corresponding evaluation factor; wherein the corresponding color gamut ratio includes: a plane color gamut coverage ratio and a three-dimensional color gamut volume ratio.

[0011] Preferably, the step of obtaining a corresponding speckle contrast expression through a light source spectrum includes:

[0012] Determine whether the light source solution is pure laser; if so, obtain the laser light source spectrum from the database and mark the normalized spectrum of the light source as The observation angle is denoted by θ o , the incident angle is denoted as θ i ; The spectral frequency difference is marked as Δv; the plane surface roughness is marked as σ h ; label the speed of light as c; label the spectral frequency as v

[0013] By formula Calculate the autocorrelation function of the normalized spectrum;

[0014] By formula The scattered wave vector difference is calculated;

[0015] By formula The normalized cross-correlation function of the speckle field is calculated;

[0016] By formula The speckle contrast expression is calculated;

[0017] If not, the standard deviation of the laser light field intensity is marked as The mean intensity of the laser light field is marked as The mean intensity of the LED light field is marked as

[0018] By formula The speckle contrast expression in an incoherent light source is calculated.

[0019] It should be noted that in the speckle suppression technology related to pure laser light sources, it is generally believed that the speckle suppression effect brought by the light source comes from the wavelength diversity; in the incoherent light source mixed with the laser light source, since the incoherent light source does not bring about the speckle phenomenon, it is approximately believed that the light field of the incoherent light source is uniform, that is, the intensity fluctuations in the mixed light field are only caused by the laser light field.

[0020] For a pure laser light source, the present invention can more accurately evaluate the influence of the laser light source on the speckle by acquiring the laser light source spectrum, observation angle, incident angle and other parameters, and calculating the autocorrelation function of the normalized spectrum, the normalized cross-correlation function of the speckle field, etc., so as to design a more effective speckle suppression strategy; for an incoherent light source mixed laser light source, by calculating the standard deviation and mean of the laser light field intensity and the mean intensity of the LED light field, the characteristics of the mixed light field can be more accurately described, and the speckle contrast in the incoherent light source can be calculated, which is helpful to understand the contribution of the incoherent light source to speckle suppression.

[0021] Preferably, the step of obtaining the chromaticity coordinates of the corresponding light source type includes:

[0022] Determine whether the light source solution is pure laser; if so, the corresponding CIE1931 chromaticity coordinates when the light source solution is pure laser are:

[0023] If not, then use the formula Calculate the chromaticity coordinate x of the mixed light of the laser and the incoherent light source i-mix and i-mix ; Where i = R, G, B, representing different primary colors; x i-Laser and i-Laser is the CIE1931 chromaticity coordinate of the laser light source, Y i-Laser is the brightness of the laser source, x i-LED and i-LED is the CIE1931 chromaticity coordinate of the LED light source, Y i-LED is the brightness of the LED light source.

[0024] The present invention provides greater flexibility for light source design by distinguishing between pure laser and incoherent light source mixed laser light sources and calculating their chromaticity coordinates respectively; it is conducive to selecting different light source combinations and brightness ratios according to specific application scenarios and needs to achieve the desired color effects and light source performance.

[0025] Preferably, the step of calculating the volume ratio of the three-dimensional color gamut according to the corresponding chromaticity coordinates includes:

[0026] The chromaticity coordinates corresponding to the pure laser are retrieved, and based on the existing color gamut theoretical formula, the corresponding chromaticity coordinates are encoded and calculated in the existing color gamut space L*a*b* to obtain CGVo and CGVx; wherein CGVo represents the maximum stereoscopic color gamut volume at the initial time, and CGVx represents the maximum stereoscopic color gamut volume after the light source properties are changed;

[0027] The three-dimensional color gamut volume ratio is calculated by the formula CGVRo=CGVx / CGVo.

[0028] Preferably, the calculating of the plane color gamut coverage ratio according to the corresponding chromaticity coordinates includes:

[0029] The chromaticity coordinates corresponding to the mixed light of the laser and the incoherent light source are retrieved, and the corresponding chromaticity coordinates are encoded and calculated based on the existing color gamut theory formula to obtain S0, S x ; Among them, S0 represents the initial plane color gamut coverage, S x It represents the color gamut coverage after the light source properties are changed;

[0030] By the formula CGCRo = S x / S o The planar color gamut coverage ratio is calculated.

[0031] The present invention is achieved by

[0032] Preferably, obtaining the evaluation factor according to the color gamut ratio and the speckle contrast expression includes:

[0033] The volume ratio of the three-dimensional color gamut is retrieved, and the evaluation factor corresponding to the pure laser is calculated by the formula F1 = 100 × CGCRo × (1-a × C);

[0034] The plane color gamut coverage ratio is retrieved, and the evaluation factor corresponding to the mixed light source is calculated by the formula F2=100×CGVRo×(1-a×C); wherein 100 is the scaling factor; a is the emphasis of the importance of color gamut performance and speckle suppression effect in light source evaluation. The smaller a is, the more the evaluation factor pays attention to the color gamut performance of the light source; the value range of a is (0, 1).

[0035] It should be noted that the larger the a value, the more important the speckle suppression effect is, and the smaller the a value, the more important the color gamut performance is; the larger the evaluation factor value, the more the light source can bring excellent speckle suppression effect while maintaining a large color gamut.

[0036] The present invention facilitates analysis and comparison by using a scaling factor; evaluates the performance of the light source in terms of speckle suppression by obtaining the light source spectrum and calculating the corresponding speckle contrast expression; and can comprehensively evaluate the performance of the light source in terms of color expression by introducing a color gamut volume ratio and a color gamut coverage ratio; at the same time, by considering the importance of color gamut expression and speckle suppression effect, the overall performance of the light source in terms of color and speckle suppression can be comprehensively evaluated.

[0037] Compared with the prior art, the present invention has the following beneficial effects:

[0038] 1. The present invention evaluates the color performance of the light source by obtaining the chromaticity coordinates of the corresponding light source type and calculating the color gamut ratio. The combination of these two aspects of evaluation provides a comprehensive evaluation of light source performance. The present invention supports the evaluation of multiple light source types, including pure laser light sources and mixed light of laser + incoherent light sources, which increases the flexibility of the evaluation. Depending on whether there is a limitation on the brightness of the light source, the three-dimensional color gamut volume ratio or the planar color gamut coverage ratio can be calculated, which further increases the adaptability of the process.

[0039] 2. By obtaining the input light source type and light source spectrum from the database, and using specific formulas and algorithms to calculate the speckle contrast expression and color gamut ratio, the accuracy of the evaluation can be improved; the evaluation results can provide guidance for light source design; when a light source performs poorly in speckle suppression, the light source design can be adjusted to reduce the speckle contrast; similarly, if the color gamut coverage or the stereoscopic color gamut volume ratio is low, the chromaticity coordinates or brightness distribution of the light source can be adjusted to improve the color performance; and in the product development process, the use of the present invention to evaluate the performance of different light source solutions is conducive to selecting the optimal solution. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0041] Figure 1 A schematic diagram of the process of selecting and evaluating a light source according to the present invention;

[0042] Figure 2 It is a schematic diagram of the specific steps of pure laser evaluation of the present invention;

[0043] Figure 3 A schematic diagram of specific steps for evaluating a mixed light source of the present invention;

[0044] Figure 4 It is a schematic diagram of the change of the evaluation factor of the pure laser of the present invention with the spectrum width;

[0045] Figure 5 It is a schematic diagram showing that the evaluation factor of the mixed light source of the present invention changes with the mixing ratio. DETAILED DESCRIPTION

[0046] The technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0047] See also Figure 1 The first aspect of the present invention provides a method for evaluating and selecting a light source for laser display, comprising:

[0048] S1: Obtain an input light source type from a database, and obtain a corresponding speckle contrast expression through the light source spectrum; wherein the light source types include: a pure laser light source, and a mixed light of a laser and an incoherent light source;

[0049] S2: Obtain the chromaticity coordinates of the corresponding light source type;

[0050] S3: Determine whether there is a light source brightness limitation; if yes, calculate the three-dimensional color gamut volume ratio according to the corresponding chromaticity coordinates; if no, calculate the plane color gamut coverage ratio according to the corresponding chromaticity coordinates;

[0051] S4: Retrieve the corresponding color gamut ratio; obtain the evaluation factor according to the color gamut ratio and the speckle contrast expression; select and evaluate the corresponding evaluation factor; wherein the corresponding color gamut ratio includes: a plane color gamut coverage ratio and a three-dimensional color gamut volume ratio.

[0052] It should be noted that the database contains all light source solutions for laser display, and the database is updated regularly.

[0053] See also Figure 2 , get the input light source type from the database. When the light source scheme is pure laser, mark the light source normalized spectrum as The observation angle is denoted by θ o , the incident angle is denoted as θ i ; The spectral frequency difference is marked as Δv; the plane surface roughness is marked as σ h ; label the speed of light as c; label the spectral frequency as v;

[0054] By formula Calculate the autocorrelation function of the normalized spectrum;

[0055] By formula The scattered wave vector difference is calculated;

[0056] By formula The normalized cross-correlation function of the speckle field is calculated;

[0057] By formula The speckle contrast expression is calculated;

[0058] The corresponding CIE1931 chromaticity coordinates obtained from the database are:

[0059] Based on the existing color gamut theory formula, the corresponding chromaticity coordinates are encoded and calculated to obtain CGVo and CGVx; wherein CGVo represents the maximum stereoscopic color gamut volume at the initial time, and CGVx represents the maximum stereoscopic color gamut volume after the light source properties are changed;

[0060] The three-dimensional color gamut volume ratio is calculated by the formula CGVRo = CGVx / CGVo;

[0061] The evaluation factor corresponding to pure laser is calculated by the formula F1=100×CGCRo×(1-a×C).

[0062] For example, now, without brightness restrictions, we evaluate and select Gaussian spectrum laser light sources with different spectral widths; import the autocorrelation function of the normalized spectrum, the normalized cross-correlation function of the speckle field, the scattering wave vector difference, and the speckle contrast expression corresponding to the Gaussian spectrum laser light source into Matlab software; Take the observation angle , angle of incidence All are 90°, i.e. normal incidence; At this time, the normalized spectrum of the light source It can also be written in the form of wavelength , we can get the corresponding XYZ tristimulus values ​​of the light source: ; in, , , is the CIE1931 standard chromaticity observer, and the corresponding CIE1931 chromaticity coordinates are: ; Import the corresponding CIE1931 chromaticity coordinates, the corresponding stereo color gamut volume ratio, and the corresponding evaluation factor when the light source scheme is pure laser into Matlab software; among them, when the maximum value of CGCR0 is 1, the minimum value of F is 70; set a in the corresponding evaluation factor to 0.3; Assume that the central wavelengths of the RGB three-primary color lasers are 638.4nm, 536.9nm and 445nm, and the initial spectral widths are all set to 0.1nm. The color gamut coverage is set to S0. The effect of the different spectral widths is obtained by changing the spectral width of only one of the three primary colors. At this time, Matlab software is used to generate Figure 3 (Schematic diagram of the evaluation factor of pure laser changing with spectral width); in, Figure 3(a) shows the plane color gamut coverage ratio, speckle contrast, and evaluation factor corresponding to the red light with a central wavelength of 638.4nm as the spectrum width changes; (b) shows the plane color gamut coverage ratio, speckle contrast, and evaluation factor corresponding to the green light with a central wavelength of 536.9nm as the spectrum width changes; (c) shows the plane color gamut coverage ratio, speckle contrast, and evaluation factor corresponding to the blue light with a central wavelength of 445nm as the spectrum width changes; according to Figure 4 The maximum F value can be obtained. At this time, the optimal spectral widths of the three primary colors of RGB are 32.6nm, 22.1nm, and 50.1nm, respectively, and the maximum F values ​​are 88.68, 88.46, and 94.19, respectively.

[0070] It should be noted that Figure 3 CGCRo=95% is a commonly used dividing point, which is marked to facilitate observation of color gamut reduction.

[0071] See also Figure 4 , get the input light source type from the database. When the light source is a mixture of laser and incoherent light source, the standard deviation of the laser light field intensity is marked as The mean intensity of the laser light field is marked as The mean intensity of the LED light field is marked as

[0072] By formula The speckle contrast expression in an incoherent light source is calculated;

[0073] By formula Calculate the chromaticity coordinate x of the mixed light of the laser and the incoherent light source i-mix and i-mix ; Where i = R, G, B, representing different primary colors; x i-Laser and i-Laser is the CIE1931 chromaticity coordinate of the laser light source, Y i-Laser is the brightness of the laser source, x i-LED and i-LED is the CIE1931 chromaticity coordinate of the LED light source, Y i-LED is the brightness of the LED light source;

[0074] Based on the existing color gamut theory formula, the corresponding chromaticity coordinates are encoded and calculated to obtain S0, S x; Among them, S0 represents the initial plane color gamut coverage, S x It represents the color gamut coverage after the light source properties are changed;

[0075] By the formula CGCRo = S x / S o The plane color gamut coverage ratio is calculated;

[0076] The plane color gamut coverage ratio is retrieved, and the evaluation factor corresponding to the mixed light source is calculated using the formula F2=100×CGVRo×(1-a×C).

[0077] For example, in a hybrid laser light source with an incoherent light source (taking LED as an example), since the incoherent light source does not cause speckle, its light field can be approximately considered to be uniform, that is, the intensity fluctuation in the hybrid light field is only caused by the laser light field, so the speckle contrast can be expressed as:

[0078] in, is the standard deviation of the laser light field intensity, is the mean intensity of the laser light field, is the mean intensity of the LED light field;

[0079] At this time, the chromaticity coordinate x i-mix and i-mix (i = R, G, B, representing different primary colors) can be expressed as:

[0080] Among them, x i-Laser and i-Laser is the CIE1931 chromaticity coordinate of the laser light source, Y i-Laser is the brightness of the laser source, x i-LED and i-LED is the CIE1931 chromaticity coordinate of the LED light source, Y i-LED is the brightness of the LED light source. Assuming that the brightness ratio and intensity ratio of the laser and LED are approximately equal, the mixing ratio of each primary color is α i :

[0081] Finally, you can get:

[0082]

[0083] Furthermore, for the same base color, different light source mixing ratios take values ​​α i (such as α i (1), α i (2)), we can get the following results:

[0084] It means that the CIE1931 chromaticity coordinates of the mixed light source will fall on the line connecting the two;

[0085] Based on the existing color gamut theory formula, the corresponding chromaticity coordinates are encoded and calculated to obtain S0, S x ; Among them, S0 represents the initial plane color gamut coverage, S x It represents the color gamut coverage after the light source properties are changed; S0 uses a laser combination with a line width of 0.1nm; due to the large actual difference of the mixed light source, the brightness needs to be included in the evaluation factor at this time, so we use the three-dimensional color gamut theory to describe the color gamut performance of the light source; in the three-dimensional color gamut theory, color is a complete three-dimensional physical quantity, that is, it includes brightness, hue and saturation, and the common CIEL*a*b* space is used to calculate the three-dimensional color gamut volume. At this time, the evaluation factor is: F2=100×CGVRo×(1-0.3×C); input the formula and corresponding values ​​in this example into Matlab software;

[0086] Now it is necessary to select and evaluate laser + LED mixed light sources with different mixing ratios. The laser light source used at this time is (R: 638.4nm, 0.1nm; G: 536.9nm, 0.1nm; B: 445nm, 0.1nm). The CIE1931 chromaticity coordinates of LED and the laser light source are shown in Table 1:

[0087] Table 1 CIE1931 chromaticity coordinates of laser and LED light sources

[0088] Base Color <![CDATA[(x i-Laser, and i-Laser )]]> <![CDATA[(x i-LED, and i-LED )]]> i=R (0.7175，0.2824) (0.6730，0.3188) i=G (0.2070，0.7716) (0.2850，0.6254) i=B (0.1611，0.0138) (0.1631，0.0622)

[0089] First, keep two of the three primary colors as pure lasers, and then mix the other primary color with LED, and explore different mixing ratios α in turn. i The results obtained by Matlab software are as follows Figure 5 (Schematic diagram of the evaluation factor of mixed light sources changing with the mixing ratio):

[0090] in, Figure 5 (a) shows the plane color gamut coverage ratio, speckle contrast, and evaluation factor corresponding to the red primary color as the mixing ratio changes; (b) shows the schematic diagram of the plane color gamut coverage ratio, speckle contrast, and evaluation factor corresponding to the green primary color as the mixing ratio changes; (c) shows the plane color gamut coverage ratio, speckle contrast, and evaluation factor corresponding to the blue primary color as the mixing ratio changes;

[0091] At this time, the maximum F values ​​of the three primary colors all appear when the mixing ratio is infinite, that is, LED light sources are used completely without laser light sources. The maximum F values ​​of the three primary colors of RGB are 91.35, 75.01, and 93.72, respectively. Among them, the evaluation factor F of the green primary color is too low, indicating that the addition of green LEDs will seriously reduce the color gamut, so it is not recommended. Since the maximum F values ​​of green and blue LEDs are smaller than the green and blue lasers in the first section, we only compare the equivalence relationship between the pure red laser and the red light + LED when the evaluation factors are equal. At this time, the laser with a spectral width of 32.3nm and a central wavelength of 638.4nm can be equivalent to the mixed light source with α=5.85.

[0092] It should be noted that S0 can also use several standard color gamuts, such as sRGB, P3, and Rec2020, but they need to remain unchanged in the scheme comparison to ensure that the evaluation factors are comparable;

[0093] It can be seen that the proposed laser display light source superiority evaluation factor F can be applied to light source evaluation and optimal configuration selection in different scenarios, which is beneficial to the research and development guidance and light source replacement in laser display.

[0094] Part of the data in the above formula is calculated by removing the dimension and taking its numerical value. The formula is a formula closest to the actual situation obtained by software simulation of a large amount of collected data; the preset parameters and preset thresholds in the formula are set by technical personnel in this field according to actual conditions or obtained through simulation of a large amount of data.

[0095] The working principle of the present invention is as follows: obtaining an input light source type from a database, and obtaining a corresponding speckle contrast expression through a light source spectrum; wherein the light source types include: a pure laser light source, and a mixed light of a laser and an incoherent light source; obtaining chromaticity coordinates of the corresponding light source type; judging whether there is a light source brightness limitation; if yes, calculating a three-dimensional color gamut volume ratio according to the corresponding chromaticity coordinates; if no, calculating a plane color gamut coverage ratio according to the corresponding chromaticity coordinates; retrieving the corresponding color gamut ratio; obtaining an evaluation factor according to the color gamut ratio and the speckle contrast expression; selecting and evaluating the corresponding evaluation factor; wherein the corresponding color gamut ratio includes: a plane color gamut coverage ratio and a three-dimensional color gamut volume ratio.

[0096] The above embodiments are only used to illustrate the technical method of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical method of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical method of the present invention.

Claims

1. A method for evaluating and selecting a light source for laser display, characterized in that: S1: Obtain an input light source type from a database, and obtain a corresponding speckle contrast expression through the light source spectrum; wherein the light source types include: a pure laser light source, and a mixed light of a laser and an incoherent light source; S2: Obtain the chromaticity coordinates of the corresponding light source type; S3: Determine whether there is a light source brightness limitation; if yes, calculate the three-dimensional color gamut volume ratio according to the corresponding chromaticity coordinates; if no, calculate the plane color gamut coverage ratio according to the corresponding chromaticity coordinates; S4: Retrieve the corresponding color gamut ratio; obtain the evaluation factor according to the color gamut ratio and the speckle contrast expression; select and evaluate the corresponding evaluation factor; wherein the corresponding color gamut ratio includes: a plane color gamut coverage ratio and a three-dimensional color gamut volume ratio.

2. A method for evaluating and selecting a light source for laser display according to claim 1, characterized in that: The method of obtaining a corresponding speckle contrast expression through the light source spectrum includes: Determine whether the light source solution is pure laser; if so, obtain the laser light source spectrum from the database and mark the normalized spectrum of the light source as The observation angle is denoted by θ o , the incident angle is marked as θ i ; The spectral frequency difference is marked as Δv; the plane surface roughness is marked as σ h ; label the speed of light as c; label the spectral frequency as v; By formula Calculate the autocorrelation function of the normalized spectrum; By formula The scattered wave vector difference is calculated; By formula The normalized cross-correlation function of the speckle field is calculated; By formula The speckle contrast expression is calculated; If not, the standard deviation of the laser light field intensity is marked as The mean intensity of the laser light field is marked as The mean intensity of the LED light field is marked as By formula The speckle contrast expression in an incoherent light source is calculated.

3. A method for evaluating and selecting a light source for laser display according to claim 1, characterized in that: The obtaining of the chromaticity coordinates corresponding to the light source type includes: Determine whether the light source solution is pure laser; if so, the corresponding CIE1931 chromaticity coordinates when the light source solution is pure laser are: If not, then use the formula Calculate the chromaticity coordinate x of the mixed light of the laser and the incoherent light source i-mix and i-mix ; Where i = R, G, B, representing different primary colors; x i-Laser and i-Laser is the CIE1931 chromaticity coordinate of the laser light source, Y i-Laser is the brightness of the laser source, x i-LED and i-LED is the CIE1931 chromaticity coordinate of the LED light source, Y i-LED is the brightness of the LED light source.

4. The method for evaluating and selecting a light source for laser display according to claim 1, characterized in that: The calculating the volume ratio of the three-dimensional color gamut according to the corresponding chromaticity coordinates includes: The chromaticity coordinates corresponding to the pure laser are retrieved, and based on the existing color gamut theoretical formula, the corresponding chromaticity coordinates are encoded and calculated in the existing color gamut space L*a*b* to obtain CGVo and CGVx; wherein CGVo represents the maximum stereoscopic color gamut volume at the initial time, and CGVx represents the maximum stereoscopic color gamut volume after the light source properties are changed; The three-dimensional color gamut volume ratio is calculated by the formula CGVRo=CGVx / CGVo.

5. The method for evaluating and selecting a light source for laser display according to claim 1, characterized in that: The calculating the plane color gamut coverage ratio according to the corresponding chromaticity coordinates includes: The chromaticity coordinates corresponding to the mixed light of the laser and the incoherent light source are retrieved, and the corresponding chromaticity coordinates are encoded and calculated based on the existing color gamut theory formula to obtain S0, S x ; Among them, S0 represents the initial plane color gamut coverage, S x It represents the color gamut coverage after the light source properties are changed; By the formula CGCRo = S x / S o The planar color gamut coverage ratio is calculated.

6. The method for evaluating and selecting a light source for laser display according to claim 1, characterized in that: The obtaining of the evaluation factor according to the color gamut ratio and the speckle contrast expression includes: The volume ratio of the three-dimensional color gamut is retrieved, and the evaluation factor corresponding to the pure laser is calculated by the formula F1 = 100 × CGCRo × (1-a × C); The plane color gamut coverage ratio is retrieved, and the evaluation factor corresponding to the mixed light source is calculated by the formula F2=100×CGVRo×(1-a×C); Among them, a is the emphasis of the importance of color gamut performance and speckle suppression effect in light source evaluation; the value range of a is (0, 1).

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