Light source module and uniformity improving method thereof

Abstract

A light source module comprises a substrate, a plurality of first light sources and a plurality of second light sources. The first light source is arranged on the substrate, the first light source emits a first light ray, and the first light ray has a first chromaticity. The second light source is arranged on the substrate and surrounds the first light source, the second light source emits a second light ray, the second light ray has a second chromaticity, and the first chromaticity and the second chromaticity have a chromaticity difference value (Rx, Ry).

Description

Technical Field

[0001] The embodiments of the present application are related to a method for improving light uniformity, and more particularly to a method for improving the uniformity of a light source module. Background Art

[0002] In the existing direct-type light source module, multiple light-emitting diode light sources are arranged in a matrix. In the prior art, although light-emitting diode light sources with a single chromaticity range are used to emit light, the light emitted by these light-emitting diode light sources will cause uneven chromaticity and brightness between the central area and the peripheral area of ​​the light source module after mixing. As the size of the display becomes larger and larger, the uneven chromaticity and brightness between the central area and the peripheral area becomes more and more obvious, even exceeding the manufacturer's tolerance value for the color uniformity of the light source module, and cannot meet the product's production specifications. Summary of the invention

[0003] The embodiment of the present application proposes a method for improving the uniformity of a light source module in order to solve the problems of the prior art, and includes the following steps. First, a test light source module is provided, the test light source module includes a plurality of first light sources and a test substrate, wherein the first light source emits a first light, the first light has a first chromaticity, the first light sources are arranged on a test substrate, and the test light source module has a first area and a second area. Then, at least one first light source center chromaticity coordinate is obtained from the first area, and at least one first light source edge chromaticity coordinate is obtained from the second area. Then, the chromaticity difference (Rx, Ry) between the first light source center chromaticity coordinate and the first light source edge chromaticity coordinate is calculated. Then, based on the chromaticity difference (Rx, Ry), multiple second light sources are selected outside the test light source module, the second light source emits a second light, and the second light has a second chromaticity. Finally, a product light source module is provided, wherein the product light source module includes a plurality of first light sources, a second light source, and a product substrate, the first light sources and the second light sources are arranged on the product substrate, and the second light source surrounds the first light source.

[0004] The light source module of the embodiment of the present application uses a second light source of different chromaticity to provide a compensation effect. Therefore, the difference between the central chromaticity coordinates and the edge chromaticity coordinates of the light source module used in the product of the embodiment of the present application can be reduced to between 0.001 and 0.002. Compared with the prior art, the light source module of the embodiment of the present application provides better uniformity. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 The figure shows the method for improving the uniformity of the light source module according to the embodiment of the present application.

[0006] Figure 2It is a test substrate showing the embodiments of the present application.

[0007] Figure 3 It shows the chromaticity change measured on the test substrate according to the embodiment of the present application.

[0008] Figure 4 It shows a light source module for a product according to an embodiment of the present application.

[0009] Figure 5 This is another step of the method for improving the uniformity of the light source module according to the embodiment of the present application.

[0010] Figure 6 FIG. 4 is a diagram showing a third light source selection method according to an embodiment of the present application.

[0011] Figure 7 It shows the arrangement of the third light source of the embodiment of the present application.

[0012] The reference numerals are described as follows:

[0013] S11, S12, S13, S14, S15, S16: Steps

[0014] 11: First Light Source

[0015] 12: Second light source

[0016] 13: The third light source

[0017] 21: Test substrate

[0018] 22: Product substrate

[0019] 23: Product substrate

[0020] A1: First Area

[0021] A2: Surrounding area

[0022] B0, B1, B2, B2', B3: Area

[0023] C0: Center point

[0024] L1: Extension line

[0025] L2: Extension line DETAILED DESCRIPTION

[0026] In the embodiments of the present application, in order to solve the above-mentioned problem of uneven chromaticity, light sources of different chromaticities are used, and the light emitted by several light sources is mixed to achieve a more uniform chromaticity performance. The light source referred to here can be an element that can emit light, such as an LED Package, an LED chip or a mini LED. In addition, the arrangement of light sources of different chromaticities can further improve the uniformity. The following first describes how to select light sources of different chromaticities.

[0027] Figure 1 The present invention is a method for improving the uniformity of a light source module according to an embodiment of the present application, comprising the following steps. First, a test light source module is provided, wherein the test light source module comprises a plurality of first light sources and a test substrate, wherein the first light sources emit a first light, the first light has a first chromaticity, the first light sources are arranged on a test substrate, and the test light source module has a first area and a second area (S11). Then, at least one first light source center chromaticity coordinate is obtained from the first area, and at least one first light source edge chromaticity coordinate is obtained from the second area (S12). Next, the chromaticity difference (Rx, Ry) between the first light source center chromaticity coordinate and the first light source edge chromaticity coordinate is calculated (S13). Then, based on the chromaticity difference (Rx, Ry), a plurality of second light sources are selected outside the test light source module (first light source), wherein the second light sources emit a second light, and the second light has a second chromaticity (S14). Finally, a product light source module is used, wherein the product light source module includes a plurality of first light sources, a second light source, and a product substrate, wherein the first light sources are disposed on the product substrate, and the second light sources surround the first light sources (S15).

[0028] In one embodiment, the chromaticity coordinates can be obtained through experimental testing or software simulation, and the above disclosure does not limit the present application.

[0029] Figure 2 1 is a test substrate for displaying the embodiments of the present application. Figure 2 The first light source 11 is arranged on the test substrate 21, and the test light source module has a first area A1 and a second area A2. The first light source center chromaticity coordinates are obtained from the first area A1, and the first light source edge chromaticity coordinates are obtained from the second area A2.

[0030] Figure 3 2 is a graph showing the chromaticity change measured on the test substrate according to the embodiment of the present application. Figure 3In one embodiment, the light source center chromaticity coordinates (X1, Y1) (i.e., the chromaticity of the first light source) fall within region B1 (a single grid region in this embodiment) of the CIE 1931 chromaticity diagram, and the first light source edge chromaticity coordinates (X0, Y0) fall within region B0 (a 4-grid region in this embodiment) adjacent to region B1. In other words, the chromaticity difference (Rx, Ry) can be obtained by subtracting the first light source edge chromaticity coordinates (X0, Y0) from the light source center chromaticity coordinates (X1, Y1). In one embodiment, the absolute value of the chromaticity difference between each point in region B0 and each point in region B1 is less than 0.006, and the above disclosure does not limit the present application. For example, in a light source module with a larger size, the absolute value of the chromaticity difference between each point in region B0 and each point in region B1 may also be greater than 0.006.

[0031] In one embodiment, based on the chromaticity difference (Rx, Ry), a plurality of second light sources are selected in addition to the test light source module (first light source), and these second light sources generate second light, and the second light has a second chromaticity (X2, Y2). For example, the second chromaticity of the selected second light source falls within the above Figure 3 In other words, the second chromaticity (X2, Y2) is obtained by the following formula:

[0032] X2=X1+Rx

[0033] Y2=Y1+Ry

[0034] Figure 4 This is a light source module for a product of an embodiment of the present application. Figure 4 In this embodiment, the first light source 11 and the second light source 12 are disposed on the product substrate 22 , and the second light source 12 surrounds the first light source 11 .

[0035] In one embodiment of the present application, the chromaticity difference (Rx, Ry) is obtained by subtracting the chromaticity coordinates (X0, Y0) of the edge of the first light source from the chromaticity coordinates (X1, Y1) of the center of the light source. That is, Rx and Ry of the chromaticity difference (Rx, Ry) can be positive or negative. In one embodiment, the second chromaticity is equal to the first chromaticity plus the chromaticity difference (Rx, Ry).

[0036] In another embodiment, based on a different calculation method of the chromaticity difference (Rx, Ry) or other design considerations such as uniformity, the second chromaticity may also be equal to the first chromaticity minus the chromaticity difference (Rx, Ry). The above disclosure does not limit the present application.

[0037] Figure 5 This is another step of the method for improving the uniformity of the light source module of the embodiment of the present application. Figure 5In one embodiment, the method for improving uniformity of a light source module further comprises the following steps: According to the chromaticity difference (Rx, Ry), a plurality of third light sources are selected outside the test light source module (first light source), the third light source generates a third light, the third light has a third chromaticity, the third chromaticity is different from the second chromaticity and the first chromaticity, wherein the product light source module further comprises the third light sources, the third light source surrounds the first light source, and the second light source surrounds the third light source (S16).

[0038] Figure 6 FIG. 2 is a diagram showing a third light source selection method according to an embodiment of the present application. Figure 6 In one embodiment, the first chromaticity (X1, Y1) falls in area B1 of the CIE 1931 chromaticity diagram (a single grid area in this embodiment), the aforementioned first light source edge chromaticity coordinates (X0, Y0) fall in area B0 adjacent to area B1 (a 4-grid area in this embodiment), and the second chromaticity (X2, Y2) falls in area B2' (a single grid area in this embodiment). The third chromaticity (X3, Y3) falls in area B3 (a single grid area in this embodiment). In one embodiment, the third chromaticity is equal to the first chromaticity plus a compensation value (Rx / 2, Ry / 2). In other words, the third chromaticity (X3, Y3) is obtained by the following formula:

[0039] X3=X1+Rx / 2

[0040] Y3=Y1+Ry / 2

[0041] Figure 7 2 is a diagram showing the arrangement of the third light source in the embodiment of the present application. Figure 7 The first light source 11 , the second light source 12 and the third light source 13 are disposed on a product substrate 23 . The third light source 13 surrounds the first light source 11 , and the second light source 12 surrounds the third light source 13 .

[0042] From the perspective of the device, refer to Figure 4 In another embodiment, the present application provides a light source module, including a substrate 22, a plurality of first light sources 11, and a plurality of second light sources 12. The first light sources 11 are disposed on the substrate 22, wherein the first light source emits a first light having a first chromaticity. The second light sources 12 are disposed on the substrate 22 and surround the first light sources 11, wherein the second light source 11 emits a second light having a second chromaticity, wherein the first chromaticity and the second chromaticity have a chromaticity difference (Rx, Ry).

[0043] In one embodiment, the absolute value of Rx is less than 0.006, and the absolute value of Ry is less than 0.006. For example, the absolute value of Rx may be 0.005, and the absolute value of Ry may be 0.005. As mentioned above, the above disclosure does not limit the present application. For example, in a light source module with a larger size, the absolute value of Rx may also be greater than 0.006, and the absolute value of Ry may also be greater than 0.006.

[0044] In one embodiment, the first light sources 11 are arranged in a matrix. However, the above disclosure does not limit the present application. For example, in another embodiment, the first light sources 11 can also be arranged in a concentric circle.

[0045] Reference Figure 4 In one embodiment, the light source module has a center point C0, and an extension line L1 extends from the center point C0. The ratio of the number of the first light source 11 to the second light source 12 on the extension line L1 is between 2:1 and 4:3. In this embodiment, the difference between the center chromaticity coordinate and the edge chromaticity coordinate of the light source module (product light source module) can be reduced to between 0.001 and 0.002.

[0046] Reference Figure 7 In another embodiment, the light source module includes a substrate 23, a plurality of first light sources 11, a plurality of second light sources 12, and a plurality of third light sources 13. The third light sources 13 are disposed on the substrate 23, wherein the third light source 13 emits a third light, and the third light 13 has a third chromaticity, which is different from the second chromaticity and the first chromaticity. The third light source 13 surrounds the first light source 11, and the second light source 12 surrounds the third light source 13.

[0047] Reference Figure 7 In one embodiment, the light source module has a center point C0, and an extension line L2 extends from the center point C0. The number ratio of the first light source 11, the third light source 13 and the second light source 12 on the extension line L2 is 2:2:1. In this embodiment, the difference between the center chromaticity coordinates and the edge chromaticity coordinates of the light source module (product light source module) can be reduced to close to 0.001.

[0048] The light source module of the embodiment of the present application uses a second light source of different chromaticity to provide a compensation effect. Therefore, the difference between the central chromaticity coordinates and the edge chromaticity coordinates of the light source module used in the product of the embodiment of the present application can be reduced to between 0.001 and 0.002. Compared with the prior art, the light source module of the embodiment of the present application provides better uniformity.

[0049] Although the present application has been disclosed as above with specific preferred embodiments, it is not intended to limit the present application. Anyone familiar with this technology can still make slight changes and modifications without departing from the spirit and scope of the present application. Therefore, the scope of protection of the present application shall be determined by the definition of the attached claims.

Claims

1. A method for improving uniformity of a light source module, comprising the following steps: A test light source module is provided, the test light source module comprising a plurality of first light sources and a test substrate, wherein: The plurality of first light sources emit a first light having a first chromaticity. The plurality of first light sources are arranged on a testing substrate. The testing light source module has a first area and a second area. Obtain at least one first light source center chromaticity coordinate from the first area, and obtain at least one first light source edge chromaticity coordinate from the second area; The chromaticity difference (Rx, Ry) between the central chromaticity coordinates of the first light source and the edge chromaticity coordinates of the first light source is calculated: Selecting a plurality of second light sources according to the chromaticity difference (Rx, Ry), wherein the plurality of second light sources emit a second light having a second chromaticity; A product light source module is provided. The product light source module includes a plurality of the first light sources, a plurality of the second light sources and a product substrate. The plurality of first light sources and the plurality of second light sources are arranged on the product substrate. The plurality of second light sources surround the plurality of first light sources.

2. The method for improving uniformity of a light source module according to claim 1, wherein: The second chromaticity is equal to the first chromaticity plus the chromaticity difference (Rx, Ry).

3. The method for improving uniformity of a light source module according to claim 1, wherein: The second chromaticity is equal to the first chromaticity minus the chromaticity difference (Rx, Ry).

4. The method for improving uniformity of a light source module according to claim 1 or 2, further comprising the following steps: A plurality of third light sources are selected according to the chromaticity difference (Rx, Ry), wherein the plurality of third light sources emit a third light, wherein the third light has a third chromaticity, and the third chromaticity is different from the second chromaticity and the first chromaticity, in, The product light source module further includes a plurality of third light sources, wherein the plurality of third light sources surround the plurality of first light sources, and the plurality of second light sources surround the plurality of third light sources.

5. The method for improving uniformity of a light source module according to claim 4, wherein: The third chromaticity is equal to the first chromaticity plus a compensation value 6. A light source module, comprising: a substrate; A plurality of first light sources are disposed on the substrate, wherein the plurality of first light sources emit a first light having a first chromaticity; A plurality of second light sources are disposed on the substrate and surround the plurality of first light sources, wherein the plurality of second light sources emit a second light having a second chromaticity, wherein the first chromaticity and the second chromaticity have a chromaticity difference (Rx, Ry).

7. The light source module according to claim 6, wherein: The light source module has a center point, and an extension line is extended from the center point. The quantity ratio of the first light source to the second light source on the extension line is between 2:1 and 4:

3.

8. The light source module as claimed in claim 6, further comprising a plurality of third light sources disposed on the substrate, wherein: The plurality of third light sources emit a third light having a third chromaticity which is different from the second chromaticity and the first chromaticity. The plurality of third light sources surround the plurality of first light sources, and the plurality of second light sources surround the plurality of third light sources.

9. The light source module according to claim 8, wherein: The light source module has a center point, and an extension line is extended from the center point. The number ratio of the first light source, the third light source and the second light source on the extension line is 2:2:

1.

10. The light source module according to claim 6, wherein: The plurality of first light sources are arranged in a matrix or concentric circles, and the light source is selected from a light emitting diode, a light emitting diode chip or a mini light emitting diode.

Images