JP2012225858A - Inspection device for light-emitting device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simultaneously inspect light emitted from a front face of a light-emitting element and light emitted from a side face of the light-emitting element.SOLUTION: There is provided an inspection device 200 for a light-emitting device 100 which measures luminance and chromaticity of light emitted from a front face 103a and a side face 103b of an LED element 103 provided for the light-emitting device to inspect presence of color unevenness in emission light. The inspection device includes: a diffusion member 1 which is arranged opposing to the light-emitting device 100 and installed at a position to which light emitted from the front face 103a of the LED element 103 and light emitted from the side face 103b of the LED element 103 can be projected in a separate manner; a light receiver 2 which receives light projected on the diffusion member 1; and a controller 3 which computes luminance and chromaticity of light on the basis of a light receiving result by the light receiver 2.

Description

  The present invention relates to an inspection device for a light emitting device.

Conventionally, light from an LED element is imaged, a video signal of the imaged light is converted into a digital signal, and the digital signal data is compared with a predetermined reference value to determine whether or not it is within a predetermined threshold range An inspection apparatus that inspects the display color or the like of the emitted light of the LED element by determining the above is known (for example, see Patent Document 1).
In addition, an inspection method is known in which an organic LED display is caused to emit light, two images are picked up by an imaging device, and luminance uniformity of the organic LED display is measured from the images (see, for example, Patent Document 2).

  By the way, in recent years, the surface of the LED element is covered with a phosphor particle layer, and a white color is generated by a color mixture of light emitted from the LED element and light emitted from the phosphor particle layer after absorbing the light of the LED element and converting the wavelength. A light-emitting device that obtains system light is widely used (see, for example, Patent Document 3).

Japanese Patent No. 4530429 Special table 2008-513968 gazette JP-A-11-040858

  In the light emitting device described in Patent Document 3, the phosphor particle layer may not be uniform on the front surface (upper surface) and the side surface of the LED element. In such a case, the amount of light emitted from the front surface of the LED element is different from the amount of light emitted from the side surface of the LED element, and color unevenness occurs in the emitted light of the LED element. Therefore, in order to specify the presence or absence of color unevenness, etc., it is necessary to inspect each of the light emitted from the front surface of the LED element and the light emitted from the side surface of the LED element, and multiple inspections are required. Is done.

  Therefore, an object of the present invention is to provide a light-emitting element inspection apparatus capable of simultaneously inspecting light emitted from the front surface of a light-emitting element and light emitted from a side surface of the light-emitting element.

In order to solve the above problems, according to the present invention,
A light-emitting device inspection device that measures the luminance and chromaticity of light emitted from the front and side surfaces of a light-emitting element provided in the light-emitting device, and inspects the presence or absence of color unevenness of the emitted light,
A diffusing member installed opposite to the light emitting device and installed at a position where the light emitted from the front surface of the light emitting element and the light emitted from the side surface of the light emitting element can be separated and projected,
A light receiver for receiving the light projected on the diffusion member;
A control device for calculating brightness and chromaticity of light based on a light reception result by the light receiver;
An inspection apparatus for a light emitting device is provided.

  According to the present invention, the diffusion member is installed at a position where the light emitted from the front surface of the light emitting element and the light emitted from the side surface of the light emitting element can be separately projected, and the light projected on the diffusion member is Since a light receiving device is provided and a control device is provided for calculating the luminance and chromaticity of the received light, the luminance and chromaticity of the light emitted from the front surface of the light emitting element and the side surface of the light emitting element are emitted. The brightness and chromaticity of the light can be measured simultaneously. Thereby, it is possible to easily inspect whether or not color unevenness occurs in the emitted light of the light emitting device.

It is a mimetic diagram showing a schematic structure of an inspection device concerning this embodiment. It is sectional drawing and the front view of the diffusion member of a test | inspection apparatus. It is a block diagram which shows roughly the control structure of an inspection apparatus. It is a flowchart which shows an example of the operation | movement which concerns on the inspection process by an inspection apparatus. It is a figure explaining the inspection apparatus which concerns on the modification 1, Comprising: It is sectional drawing which shows the diffusion member and partition member of an inspection apparatus. It is a figure explaining the inspection apparatus which concerns on the modification 2, Comprising: It is sectional drawing which shows the diffusion member and partition member of an inspection apparatus.

  EMBODIMENT OF THE INVENTION Below, the form for implementing this invention is demonstrated using drawing. However, although various technically preferable limitations for implementing the present invention are given to the embodiments described below, the scope of the invention is not limited to the following embodiments and illustrated examples.

As shown in FIG. 1, the inspection apparatus 200 includes a diffusing member 1 disposed facing the LED element 103 of the light emitting device 100, a light receiver 2 that images light projected onto the diffusing member 1, and the like. Furthermore, the inspection apparatus 200 includes a control device 3 that performs various processes.
The inspection device 200 has the light emitting device 100 as an inspection target, and the luminance and chromaticity of light emitted from the front surface 103 a of the LED element 103 provided in the light emitting device 100 and the light emitted from the side surface 103 b of the LED element 103. This is an inspection device that measures luminance and chromaticity at the same time and inspects the presence or absence of color unevenness of the emitted light of the light emitting device 100.

The light emitting device 100 includes a package 101 having a concave cross section as shown in FIG. A rectangular parallelepiped LED element (light emitting element) 103 is disposed in the recess (bottom) of the package 101. The LED element 103 has a back surface fixed to the package 101, and emits light from the front surface 103a and the side surface 103b. Here, a configuration in which one LED element 103 is provided for one package 101 is illustrated, but a plurality of LED elements 103 may be provided in a recess of one package 101.
In the present embodiment, a blue LED element is used as the LED element 103. The blue LED element is formed, for example, by laminating an n-GaN-based cladding layer, an InGaN light-emitting layer, a p-GaN-based cladding layer, and a transparent electrode on a sapphire substrate.
A wavelength conversion unit 106 is formed in the recess of the package 101 so as to seal the periphery of the LED element 103. The wavelength converter 106 is a part that converts light having a predetermined wavelength emitted from the LED element 103 into light having a different wavelength. The wavelength conversion unit 106 contains phosphor particles that are excited by light of a predetermined wavelength from the LED element 103 and emit fluorescence having a wavelength different from the excitation wavelength.
The light emitting device 100 configured as described above is fixed at a predetermined position by the jig 4 (see FIG. 1) and connected to the control device 3 (see FIG. 3).

  The diffusion member 1 is a translucent plate-like member formed in a rectangular shape. As shown in FIG. 2A, the diffusing member 1 is disposed so as to face the light emitting device 100, and light emitted from the LED element 103 is taken into the diffusing member 1. The diffusing member 1 is disposed at a position where light emitted from the front surface 103 a of the LED element 103 and light emitted from the side surface 103 b of the LED element 103 are projected separately. For example, the LED element 103 is formed in a 200 μm square, the length in the height direction of the package 101 (direction parallel to the side surface 103b of the LED element 103) is 2 mm, and the width direction of the package 101 (the front surface of the LED element 103). When the length in the direction parallel to 103a is 3 mm, the diffusing member 1 is disposed at a position within 2 mm from the front surface of the light emitting device 100. In the illustrated example, the diffusing member 1 is disposed at a position in contact with the front surface of the light emitting device 100 (a position of 0 mm from the front surface of the light emitting device 100). As a result, as shown in FIG. 2 (b), the light emitted from the front surface 103 a of the LED element 103 is projected on the center of the diffusing member 1 on the front surface of the diffusing member 1, and around the LED element 103. The light emitted from the side surface 103b is projected. FIG. 2B illustrates a case where the amount of light emitted from the front surface 103a of the LED element 103 is different from the amount of light emitted from the side surface 103b, resulting in color unevenness.

The light receiver 2 includes a camera lens unit (light receiving unit) 21, and the camera lens unit 21 is arranged facing the light emitting device 100. The light receiver 2 images the light emitted from the LED element 103, taken into the diffusing member 1 and projected. The light receiver 2 transfers the imaging data to the control device 3.
For example, a CCD camera is preferably used as the light receiver 2. For example, a standard lens, a macro lens, a wide-angle lens, and the like are attached to the camera lens unit 21 of the light receiver 2, and the lens can be appropriately replaced. When the light emitting device 100 is provided with a plurality of LED elements 103, the plurality of LED elements 103 can be imaged simultaneously by exchanging the lens of the camera lens unit 21 with a wide-angle lens, and the inspection time can be shortened.

  The light receiver 2 has a moving mechanism 22, and the moving mechanism 22 causes the light receiver 2 to be orthogonal to the light emitting direction of the light emitting device 100 (the direction indicated by the arrow in FIG. 1). 1 is movable in a vertical direction, a direction perpendicular to the paper surface of FIG. 1 and a parallel direction (left-right direction in FIG. 1). Thereby, even if the LED element 103 has a size that does not fit in the finder of the light receiver 2, it is possible to capture the emitted light projected on the diffusing member 1 by moving the light receiver 2 by the moving mechanism 22. And inspection time can be shortened.

The inspection device 200 having the above configuration is provided with a control device 3 (PC) shown in FIG. As shown in FIG. 3, the light receiver 2 and the light emitting device 100 are connected to the control device 3.
The control device 3 is configured to perform software control of the operation of these members. By key input to the control device 3, the light receiving device 2 is moved by the moving mechanism 22, the light emitting device 100 is turned on, and the light receiving device 2 Acquisition of imaging data, various processes based on the acquired imaging data, and the like can be performed. When acquiring the imaging data from the light receiver 2, the control device 3 divides the light projected on the diffusing member 1 into squares of a predetermined size based on the acquired imaging data, as shown in FIG. Luminance and chromaticity are calculated for each square. The size and shape of the grids shown in FIG. 2 (b) are examples and are not limited to this, and the size and shape of the grids can be arbitrarily set as appropriate.

  Next, a light emitting element inspection method using the inspection apparatus 200 will be described with reference to FIG.

  First, the light emitting device 100 to be inspected is fixed to the jig 4. Conditions such as the number of LED elements 103 provided in the light emitting device 100 to be inspected are input to the control device 3, and based on this, the light receiver 2 is moved by the moving mechanism 22. Further, an optimal lens is selected according to the size and number of the LED elements 103, and the selected lens is mounted on the camera lens unit 21 of the light receiver 2 (step S1).

Next, the LED element 103 of the light emitting device 100 is caused to emit light (step S2). Thereby, light is emitted from the front surface 103 a and the side surface 103 b of the LED element 103. The light emitted from the LED element 103 is taken into the diffusing member 1, and the light emitted from the front surface 103a and the light emitted from the side surface 103b of the LED element 103 are projected separately.
Next, the light of the LED element 103 projected on the diffusing member 1 by the light receiver 2 is imaged (step S3).

  Imaging data of the imaged light of the LED element 103 is acquired from the light receiver 2 (step S4). As shown in FIG. 2B, based on the acquired imaging data, the light projected on the diffusing member 1 is divided into squares having a predetermined shape, and the luminance and chromaticity are calculated for each square (step S5). ). Thereby, the brightness | luminance and chromaticity of the light radiate | emitted from the LED element 103 front surface 103a and the brightness | luminance and chromaticity of the light radiate | emitted from the side surface 103b of the LED element 103 can be obtained.

Finally, the calculated brightness and chromaticity of the LED element 103 are compared with reference value data input in advance for each square (step S6). The difference between the calculated value and the reference value is calculated, and the comparison result is output to a predetermined output means (for example, an image display unit (not shown)) (step S7).
Thereby, the inspection process by the inspection apparatus 200 is completed.

According to the above embodiment, the diffusing member 1 is provided at a position where the light emitted from the front surface 103a of the LED element 103 and the light emitted from the side surface 103b of the LED element 103 can be separated and projected. Since a light receiver that images the light projected on the diffusing member 1 is provided, and a control device 3 that calculates the luminance and chromaticity of the light based on the imaging data from the light receiver is provided, the front surface 103a of the LED element 103 is provided. The light emitted from the side and the light emitted from the side surface 103b can be inspected at the same time. Thereby, it is possible to easily confirm whether or not color unevenness occurs in the light emitted from the LED element 103.
Further, the control device 3 divides the light projected on the diffusing member 1 into squares based on the imaging data obtained from the light receiver 2, and calculates luminance and chromaticity for each square. It is possible to easily confirm in which part of a certain light emitting device 100 color unevenness occurs.

  In addition, since the camera lens unit 21 of the light receiver 2 can be provided with a wide-angle lens, even if the light emitting device 100 is provided with a plurality of LED elements 103, each of the emitted lights of the plurality of LED elements 103 is provided. Can be imaged simultaneously for inspection. Therefore, even if a plurality of LED elements 103 are provided in the light emitting device 100 to be inspected, the inspection does not require a long time.

  In addition, the light receiver 2 can be moved in a direction orthogonal to and parallel to the light emission direction of the light emitting device 100 by the moving mechanism 22, so that the LED element 103 can fit in the finder of the light receiver 2. Even if the size is not large, by moving the light receiver 2 by the moving mechanism 22, the emitted light of the LED element 103 can be imaged and the time required for the inspection can be shortened.

  In the illustrated example, the light emitting device 100, the diffusing member 1, and the light receiver 2 are arranged side by side in the horizontal direction. However, this is merely an example, and the present invention is not limited thereto. That is, the diffusing member 1 is disposed at a position where the light emitted from the front surface 103 a and the light emitted from the side surface 103 b of the LED element 103 can be separately projected, and the light receiver 2 is projected onto the diffusing member 1. Any arrangement may be used as long as it is arranged at a position where it can pick up light. For example, the light emitting device 100 may be installed upward, and the diffusing member 1 and the light receiver 2 may be arranged side by side above the light emitting device 100.

<Modification 1>
Next, Modification 1 of the inspection apparatus 200 will be described with reference to FIG. In the inspection apparatus according to the first modification, the configuration other than the configuration described below is substantially the same as that of the inspection device 200 of the above embodiment, and thus detailed description thereof is omitted.

  The inspection apparatus 200 according to the modification 1 includes a partition member 6 in addition to the diffusion member 1, the light receiver 2, and the control device 3.

As shown in FIG. 5, the partition member 6 is provided between the light emitting device 100 and the diffusing member 1, and is emitted from the front surface 103 a of the LED element 103 and enters the diffusing member 1, and the side surface of the LED element 103. It arrange | positions so that the light radiate | emitted from 103b and injecting into the diffusion member 1 may be partitioned off. That is, the partition member 6 is formed in a square tube shape, and is erected on the opposite surface of the light emitting device 100 on both surfaces of the diffusing member 1, and the tip thereof is the boundary between the front surface 103 a and the side surface 103 b of the LED element 103. It extends until it reaches the part. That is, the partition member 6 is disposed so as to surround the front surface 103 a of the LED element 103. Thereby, the light emitted from the front surface 103a of the LED element 103 and incident on the diffusing member 1 and the light emitted from the side surface 103b and incident on the diffusing member 1 can be partitioned, and the light emitted from the front surface 103a and The light emitted from the side surface 103b can be separated and projected onto the diffusing member 1.
Note that the surface of the partition member 6 may be subjected to mirror finishing. In this case, a part of the light emitted from the LED element 103 is reflected by the partition member 6, so that most of the light emitted from the LED element 103 is taken into the diffusing member 1 and the inspection accuracy with respect to the light emitting device 100 is detected. Can be improved.

  As described above, according to the inspection apparatus 200 according to the first modification, the light emitted from the front surface 103 a and the light emitted from the side surface 103 b of the LED element 103 are partitioned by the partition member 6 and taken into the diffusion member 1. Therefore, the inspection accuracy of the presence or absence of color unevenness with respect to the LED element 103 can be further improved.

<Modification 2>
Subsequently, a second modification of the inspection apparatus 200 will be described with reference to FIG. Note that the inspection apparatus according to the second modification has substantially the same configuration as that of the inspection apparatus 200 according to the first modification, except for the structure described below, and a detailed description thereof will be omitted.
The inspection device 200 according to Modification 2 is different from the inspection device 200 according to Modification 1 in the shape of the partition member 7.

The partition member 7 is formed in a square tube shape, and stands on the opposing surface of the LED element 103 on both surfaces of the diffusing member 1, and its tip is separated from the LED element 103. That is, the length from the base end portion of the partition member 7 installed in the diffusing member 1 to the tip end portion of the partition member 7 is the length in the height direction of the package 101 (direction parallel to the side surface 103b of the LED element 103). Or less than 1/2. Further, the partition member 7 has an angle θ (see FIG. 6) formed by a straight line connecting the boundary between the front surface 103 a and the side surface 103 b of the LED element 103 and the front end portion of the partition member 7 and the front surface 103 a of the LED element 103. It arrange | positions so that it may become ~ 30 degree. Thereby, the light emitted from the front surface 103a of the LED element 103 and incident on the diffusion member 1 can be separated from the light emitted from the side surface 103b of the LED element 103 and incident on the diffusion member 1, and emitted from the front surface 103a. And the light emitted from the side surface 103b can be separated and projected onto the diffusing member 1.
In addition, the partition member 7 has a rectangular cylindrical shape, but the light emitted from the front surface 103a of the LED element 103 and incident on the diffusion member 1 and the light emitted from the side surface 103b of the LED element 103 are diffused. A cylindrical shape or a polygonal cylindrical shape may be used as long as it can be separated from the light incident on the.

As described above, according to the inspection apparatus 200 according to the modification example 2, the light emitted from the front surface 103a and the light emitted from the side surface 103b of the LED element 103 are partitioned by the partition member 6 and taken into the diffusion member 1. Therefore, the inspection accuracy of the presence or absence of color unevenness with respect to the LED element 103 can be further improved.
Further, since the partition member 7 is arranged away from the LED element 103, the partition member 7 can be prevented from touching the electrode wire connected around the LED element 103, and the light emission of the LED element 103 is hindered. Can be suppressed.

DESCRIPTION OF SYMBOLS 1 Diffusion member 2 Light receiver 3 Control apparatus 4 Jig 6 Partition member 7 Partition member 21 Camera lens part 22 Moving mechanism 100 Light-emitting device 101 Package 103 LED element (light-emitting element)
103a Front 103b Side 106 Wavelength conversion unit 200 Inspection device

Claims (5)

A light-emitting device inspection device that measures the luminance and chromaticity of light emitted from the front and side surfaces of a light-emitting element provided in the light-emitting device, and inspects the presence or absence of color unevenness of the emitted light,
A diffusing member installed opposite to the light emitting device and installed at a position where the light emitted from the front surface of the light emitting element and the light emitted from the side surface of the light emitting element can be separated and projected,
A light receiver for receiving the light projected on the diffusion member;
A control device for calculating brightness and chromaticity of light based on a light reception result by the light receiver;
An inspection apparatus for a light-emitting device, comprising:   The light-emitting device inspection device according to claim 1, wherein a lens provided in a light-receiving portion of the light-receiving device is replaceable.   The light-emitting device inspection apparatus according to claim 1, wherein a wide-angle lens is provided in a light-receiving portion of the light receiver.   The said light receiver has a moving mechanism for moving to the direction orthogonal to the light emission direction of the said light-emitting device, and a parallel direction, The Claim 1 characterized by the above-mentioned. Inspection device for light emitting device.   Light that is provided between the light emitting device and the diffusing member and is emitted from the front surface of the light emitting element and incident on the diffusing member; and light that is emitted from the side surface of the light emitting element and incident on the diffusing member. The inspection apparatus for a light-emitting device according to any one of claims 1 to 4, further comprising a partition member for partitioning.

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