JP5247892B2 - Emission status measurement device - Google Patents

Description

  The present invention relates to a light emission state measuring apparatus that receives light from a semiconductor light emitting element such as an LED and measures the light emission state thereof.

  Patent Document 1 discloses a technique for measuring the distribution of the intensity of light emitted from an LED using a photographed image obtained by applying the light emitted from the LED to a translucent screen and photographing the image with a photographing device. Yes.

Japanese Patent Publication No. 5-39532

  However, the technique disclosed in Patent Document 1 is not an apparatus that can inspect the light emission status and appearance of the LED itself.

  The present invention has been made in view of the above problems, and an example of the object thereof is to provide a light emission state measuring device capable of inspecting the light emission state and appearance of the LED chip itself with a simple configuration. .

The light emission state measuring device of the present invention is a light emission state measuring device that receives light emitted from an LED and directly measures the light emission state, and is disposed on the light emission central axis of the LED and facing the LED. Image pickup means for picking up the light emission state of the LED, and a lens portion that receives light emitted from the LED and emits the light toward the image pickup means, and the lens portion includes the LED And the imaging means, and is arranged nearer to the LED than the imaging means, and the lens unit is composed of a plurality of lenses, and is at least closest to the LED among the plurality of lenses The lens arranged at the position is constituted by a Fresnel lens.

It is explanatory drawing of the light emission condition of LED in the 1st Embodiment of this invention. It is explanatory drawing of the method of measuring LED light emission condition by this embodiment. It is a comparative example referred when demonstrating the method to measure the light emission condition of LED by this embodiment. It is explanatory drawing of the light reception module for semiconductor light emitting elements of 1st Embodiment. It is explanatory drawing of the outline | summary of the light emission condition measuring apparatus. It is explanatory drawing of the effect of this embodiment. It is a comparative example used when demonstrating the effect of this embodiment.

Hereinafter, the first embodiment of the present invention will be described in detail with reference to FIG.
FIG. 1 is an explanatory diagram of a light emission state of the LED 101 according to the first embodiment of the present invention.

As described in FIG. 1A, an LED (Light Emitting Diode) 101 emits light from a light emitting surface 101a. The normal line of the light emitting surface 101a of the LED 101 is referred to as a light emission central axis (LCA).
When the light emitted from the LED 101 is not centered on the normal direction of the light emitting surface 101a (for example, when light is emitted centering on the oblique direction in FIG. 1A), the light is emitted by the LED 101. The direction that becomes the center of the emitted light is called the emission central axis.
FIG. 1B is an external view of the LED 101 viewed from the light emitting surface 101a side on the light emission central axis. Note that the shape of the LED 101 is not limited to such a shape.
Here, it is desirable that the light intensity of the LED 101 is uniform in all portions designed to emit light.
In other words, the LED 101 that satisfies a certain performance by measuring the situation such as whether there is no part that does not emit light in the LED 101 or whether the intensity of the light is within a certain range even if it emits light. It is necessary to separate only the water.
Note that the light emission status of the LED 101 is collectively referred to as the light emission status.
In particular, it is expected that the future LED 101 will be required to have a performance with a light emission state of a certain level or more.
Therefore, it is necessary to measure the presence / absence of light emission for each part of the LED 101 and the intensity of the light emission, if any, and classify based on this. Furthermore, it is necessary to inspect whether there is any abnormality in the appearance of the LED 101.
Therefore, in this embodiment, the light emission state is measured by directly measuring how each part of the LED 101 emits light, not how the light emitted from the LED 101 is received at a certain position.
A specific method for this will be described below.

FIG. 2 is an explanatory diagram of a method for measuring the light emission state of the LED 101 according to the present embodiment.
FIG. 3 is a comparative example that is referred to when describing the method of measuring the light emission state of the LED 101 according to the present embodiment.

As shown in FIG. 2, the LED 101 that is the measurement object is disposed on the workpiece 102, and the tip of the probe needle 109 is brought into contact with the electrode of the LED 101 to apply a voltage.
As a result, the light emitted from the LED 101 is refracted by the lens unit 123 and an image (real image) of the LED 101 is formed on the CCD 105.
At that time, the lens unit 123 is disposed at a position closer to the LED 101 than the CCD 105. More specifically, the lens unit 123 is disposed at a position where the LED 101 is positioned slightly farther than the focal position D2 of the lens unit 123 on the LED 101 side.
This slightly distant position means that when the first principal point position (object side principal point) and the second principal point position (image side principal point) of the lens part 123 are both at the lens part center position C1, the lens part 123 center C1. This is a distance between the distance to the focal position D2 (focal distance, (effective focal distance)) and twice the distance from the lens section 123 center position C1 to the focal position D2.
In other words, when the first principal point position (object side principal point) and the second principal point position (image side principal point) of the lens unit 123 are both the lens part center position C1, the focal length is between 1 and 2 times. The LED 101 is disposed at the position of the distance.
This is because a real image connected to the CCD 105 is larger than the actual LED 101 within this range.
The CCD 105 is disposed at a position where the image (real image) of the LED 101 is formed.
The focal point D2 on the LED 101 side of the lens unit 123, the center C1 of the lens unit 123, the focal point D1 on the CCD 105 side of the lens unit 123, and the center of the CCD 101 are arranged on the light emission central axis of the LED 101.
The light receiving surface of the CCD 105 is arranged so as to be perpendicular to the light emission center axis.

When the LED 101, the lens unit 123, and the CCD 105 are arranged so as to have the above positional relationship, a larger real image than the actual LED 101 is formed on the CCD 105 as can be seen from FIG.
Accordingly, the state of the LED 101 can be imaged with high resolution by the CCD 105. That is, the situation is the same as when the surface of the LED 101 is photographed.
Further, since the CCD 105 is completely in focus with the LED 101, the light emission state of the LED 101 can be measured by the CCD 105.
Specifically, it is possible to determine which part of the LED 101 is not emitting light.
Furthermore, if an optical filter or the like is used, the wavelength and intensity of the light can be detected for each part even if the part emits light. In this case, it is possible not only to discriminate based on the light intensity of this embodiment but also to discriminate based on wavelength.

In addition, as can be seen from FIG. 2, in this method, light having an angle up to θ 1 can be condensed by the lens unit 123 and guided to the CCD 105. That is, a wide range of light can be condensed on the CCD 105, and measurement can be performed in a short time.
In addition, it is possible to guide light to the CCD 105 even when the light emission direction of a part of the LED 101 is in a direction different from the light emission central axis.

Furthermore, since the distance between the focused LED 101 and the lens unit 123 is short, the depth of field is shallow.
If the depth of field is shallow, the range of the focus point is narrowed, and the subject at a distance away from the focus point is photographed without being focused. In this embodiment, the position of the probe needle 109 is Is relatively far from the focus point, and the image picked up by the CCD 105 is picked up with the probe needle 109 not in focus at all.
In some cases, the image may not appear at all.
Therefore, in this method, it is possible to image only the LED 101 substantially.
It is also possible to measure the light emission state of the portion hidden behind the probe needle 109. The light hidden behind the probe needle 109 is measured by light passing through an optical path that is not blocked by the probe needle 109.

On the other hand, in the method of the comparative example shown in FIG. 3 (the method of disposing the lens unit 123 on the CCD 105 side), even if a real image is formed on the CCD 105, the size thereof is as shown in FIG. It will become a small thing. As a result, this method cannot image the LED 101 with high resolution.
In the method of the comparative example shown in FIG. 3, the range of light guided by the CCD 105 is only the range of θ2. As a result, the amount of light incident on the CCD 105 is reduced, and imaging at high speed becomes difficult accordingly. Furthermore, it becomes impossible to guide most of the light whose light emitting direction in a certain part of the LED 101 is in a direction different from the light emission central axis.
Furthermore, in the method of the comparative example shown in FIG. 3, the distance between the focused LED 101 and the lens unit 123 is long, so that the depth of field is deep.
That is, the probe needle 109 is also within the range of the depth of field, and an unnecessary probe is imaged.
As a result of imaging the probe needle 109 as well, the light emission state of the portion hidden by the probe needle 109 cannot be measured.
In FIG. 3, C2 is the center of the lens unit 123, D3 is the focal point of the lens unit 123 on the CCD 105 side, and D4 is the focal point of the lens unit 123 on the LED 101 side.

As described above, the image captured by the CCD 105 can measure the light emission state of the LED 101 with higher resolution as the magnification ratio increases. Further, the closer the lens portion 123 is to the LED 101, the larger the range of light that can be guided to the CCD 105.
Furthermore, the closer the lens unit 123 is to the LED 101, the shallower the depth of field of the probe needle 109 can be set.
If the lens unit 123 having a short focal length is used, these can be realized simultaneously.
This is because the enlargement ratio can be increased when the focal length is short.
In addition, when the focal length is short, the position of the LED 101 arranged slightly far from the focal point of the lens unit 123 can also be closer to the lens unit 123.
Furthermore, if the position of the LED 101 can be made closer to the lens unit 123, the influence of the distance difference between the focus point position and the probe needle 109 can be increased, and the depth of field of the probe needle can be reduced. Thus, the position of the probe needle 109 can be relatively greatly deviated from the depth of field. As a result, the probe needle 109 can be hardly imaged.
Therefore, the structure of an actual device (light-receiving module 1 for semiconductor light-emitting elements) capable of increasing the focal length will be described below.

  FIG. 4 is an explanatory diagram of the light-receiving module 1 for semiconductor light-emitting elements according to the first embodiment.

As shown in FIG. 4A, in the present embodiment, the light receiving module 1 for a semiconductor light emitting element includes a workpiece 102 (sample mounting table), a CCD 105, a holder 107, a signal line 111, an image processing unit 113, a communication line 115, a spacer. 117 and a lens portion 123.
However, all of these are not essential components of the light-receiving module 1 for semiconductor light-emitting elements, and it is sufficient to have at least the CCD 105 and the lens unit 123.
5 includes a probe needle 109, an electrical characteristic measuring unit 119, and a tester 151 for inspecting electrical characteristics of the LED 101, in addition to the light receiving module 1 for semiconductor light emitting elements.
LED101 is arrange | positioned on the workpiece | work 102 installed horizontally.
A holder 107 is disposed at a position facing the workpiece 102 with a space therebetween.
A CCD 105 is arranged inside the holder 107.
The LED 101, the workpiece 102, and the CCD 105 are arranged in parallel to each other.
The probe needle 109 is in contact with the LED 101 and applies a voltage to the LED 101 when measuring the amount of light and measuring the electrical characteristics.
The probe needle 109 may move while the workpiece 102 and the LED 101 are fixed, and the probe needle 109 and the LED 101 may contact each other. Conversely, the workpiece 102 and the LED 101 may move while the probe needle 109 is fixed, and the probe needle 109 and the LED 101 may come into contact with each other.
The probe needle 109 is connected to the electrical characteristic measurement unit 119.
The probe needles 109 extend radially in a direction perpendicular to the normal line of the light emitting surface 101 a of the LED 101 substantially parallel to the light emitting surface 101 a of the LED 101.

The holder 107 has a shielding part 107a and a cylindrical side part 107b.
Furthermore, the holder 107 has a cylindrical part 107d and an extending part 107e between the shielding part 107a and the cylindrical side part 107b.
The side surface portion 107b has a cylindrical shape and has a shape extending in the direction of θ = 0 ° (the light emitting surface 101a normal direction of the LED 101).
The cylindrical portion 107d has a cylindrical shape having a length of about 1.5 times the diameter of the bottom surface (circular shape). And the internal peripheral surface which forms the hollow space of the cylindrical part 107d is formed so that it may correspond with the internal peripheral surface which forms the column-shaped hollow space which the extended part 107e makes.
The diameter of the inner peripheral surface of the cylindrical portion 107d and the inner peripheral surface of the extending portion 107e, the outer peripheral surface of the cylindrical portion 107d, the inner peripheral surface of the side surface portion 107b, the outer peripheral surface of the side surface portion 107b, and the outer peripheral surface of the extending portion 107e. The diameter is large.
The central axes of the shielding portion 107a, the cylindrical portion 107d, the extending portion 107e, and the side surface portion 107b have a direction of θ = 0 °, and are the same as the normal line of the light emitting surface 101a of the LED 101.
The CCD 105 is disposed in a hollow space formed by the inner peripheral surface of the side surface portion 107b.
A circular opening 107c that forms a frustoconical hollow portion is formed at the center of the shielding portion 107a. Due to the circular opening 107c, the CCD 105 can receive light emitted from the LED 101.
The outer peripheral surface of the shielding part 107 a is formed from an outer peripheral inclined surface 107 i that is inclined toward the LED 101. A hollow space formed by the inner peripheral surface of the shielding portion 107a is formed by an inclined surface 107f, a parallel surface 107g, and a right-angle surface 107h.
From the LED 101 side, an inclined surface 107f, a parallel surface 107g, and a right angle surface 107h are formed in this order.
The inclined surface 107f is formed so that its diameter increases toward the LED 101 side, thereby forming the circular opening 107c that forms the above-mentioned frustoconical hollow portion.
The parallel surface 107g has a plane extending in the radial direction from the light emission central axis, and more specifically, the outer periphery of the upper surface of the circular opening 107c forming the frustoconical hollow portion. It has a plane extending horizontally from the position (opening surface end 107j) toward the position in the longitudinal direction corresponding to the outer peripheral position of the bottom surface. Moreover, the normal direction of the parallel surface 107g has the same direction as the light emission central axis.
The right-angled surface 107h forms a cylindrical hollow section centered on the light emission central axis.
An opening surface end 107j, which is the end of the inclined surface 107f on the CCD 105 side, is formed at a position where θ = 60 ° or more.

The lens unit 123 has a function of refracting light emitted from the LED 101 and guiding it to the CCD 105.
The lens unit 123 includes, in order from the LED 101 side, a first Fresnel lens 125a (first lens 125), a second Fresnel lens 127a (second lens 127), and a third Fresnel lens 129a (third lens 129). ).
By using a plurality of lenses in this way, the lens portion 123 having a short focal length can be obtained as a whole.
Hereinafter, the lens unit 123 will be described in more detail.

The lens unit 123 is disposed at a position closer to the LED 101 than the CCD 105. More specifically, the lens unit 123 is disposed at a position where the LED 101 is positioned slightly farther than the focal position D2 of the lens unit 123 on the LED 101 side.
This slightly distant position means that when the first principal point position (object side principal point) and the second principal point position (image side principal point) of the lens part 123 are both at the lens part center position C1, the lens part 123 center C1. This is a distance between the distance to the focal position D2 (focal distance, (effective focal distance)) and twice the distance from the lens section 123 center position C1 to the focal position D2.
In other words, when the first principal point position (object side principal point) and the second principal point position (image side principal point) of the lens unit 123 are both the lens part center position C1, the focal length is between 1 and 2 times. The LED 101 is disposed at the position of the distance.
This is because a real image connected to the CCD 105 is larger than the actual LED 101 within this range.
The CCD 105 is disposed at a position where the image (real image) of the LED 101 is formed.
Furthermore, it is preferable that the numerical aperture NA of the lens portion 123 formed from the first Fresnel lens 125a, the second Fresnel lens 127a, and the third Fresnel lens 129a is 0.86 or more.
The reason why the numerical aperture NA is preferably 0.86 or more will be described below.
First, the numerical aperture NA is
NA = nsinθ (see also FIG. 4B).
n is the refractive index of the substance that transmits the light before entering the lens.
In the present embodiment, since the light emitted from the LED 101 passes through the air and n = 1.0003, it may be considered that NA = sin θ.
Here, in most cases, the ordinary LED 101 only needs to be able to irradiate light in the range of θ up to 60 °.
In addition, in the range where θ is 60 ° or more, the intensity of normal light is weak, and it is normal not to use the range where θ is 60 ° or more.
Therefore, it is sufficient that the light up to the range of θ of 60 ° is received by the CCD 101 and the state of the light can be measured.
Therefore, if 60 ° is substituted for θ in the above equation for obtaining NA, the numerical aperture NA should be 0.86 or more.
A large numerical aperture NA means that the refractive index is high, and a high refractive index means that the focal length is short.

However, since it is difficult to set the numerical aperture NA to 0.86 or more with one lens unit 123, in this embodiment, the lens unit 123 includes the first Fresnel lens 125a, the second Fresnel lens 127a, and the third lens unit 123. The Fresnel lens 129a is formed.
That is, when the first Fresnel lens 125a, the second Fresnel lens 127a, and the third Fresnel lens 129a are combined and regarded as one lens portion 123, the numerical aperture NA is 0.86 or more. ing.

Here, the reason why the lens portion 123 is formed by the first Fresnel lens 125a, the second Fresnel lens 127a, and the third Fresnel lens 129a is as follows.
The first reason is that since the Fresnel lens can be formed thin, the first Fresnel lens 125a can be brought close to the LED 101.
That is, for example, in the case of a normal convex lens, the light emission central axis portion has a greatly swelled structure, so that it is difficult to bring the lens portion 123 close to the LED 101. The Fresnel lens 125a can be brought close to the LED 101.
The second reason is that the lens portion 123 is composed of three lens members, a first Fresnel lens 125a, a second Fresnel lens 127a, and a third Fresnel lens 129a. This is because if a bulging convex lens or the like is used, each one occupies a large space, and the thickness of the lens portion 123 increases.
The third reason is that when formed with a convex lens, the distance between the first lens center 125c and the second lens center 127c of the lens portion 123 and the distance between the second lens center 127c and the third Fresnel lens center 129c. This is because a large amount must be taken.
That is, when the distance for disposing the lens is increased in this way, the light after passing through the first lens 125 goes straight ahead for a longer distance than when the Fresnel lens is used. Similarly, the second lens The light after passing through 127 goes straight for a long distance. Then, the light travels with a large spread, and the second lens 127 and the third lens 129 for refracting the spread light within the light receiving region of the CCD 105 need to have large diameter lenses. End up.
Furthermore, a convex lens having a large diameter becomes a vicious circle in which the thickness of the light emission central axis is further increased.
As described above, when the lens portion 123 is formed using a plurality of lenses, it is more preferable to use a Fresnel lens.

The material of the Fresnel lens is preferably composed mainly of silicon.
If comprised in this way, it will become possible to make the range of the wavelength which the light reception module 1 for semiconductor light emitting elements can measure into 300 nm-1500 nm.
In other words, since the material of the Fresnel lens is mainly composed of silicon, the lens unit 123 can withstand high temperatures. And since it can endure high temperature, even if the wavelength of the light which LED101 radiates | emits is 300 nm-1500 nm, it can be used.
In addition, although plastic materials such as acrylic may be deteriorated by light, since the main component is silicon, deterioration by light can be extremely reduced.
Further, since silicon is the main component, it is possible to achieve a higher refractive index than plastic materials such as acrylic.

  In the above embodiment, the number of lenses constituting the lens unit 123 is three, but it may be more. Further, one lens may be used as long as the focal length can be shortened by one lens.

The first Fresnel lens 125a is fitted into a hollow space formed by the parallel surface 107g and the right-angle surface 107h.
In addition, the second Fresnel lens 127a and the third Fresnel lens 129a are fitted in this order along the light emission central axis at a position separated from the inner peripheral surface of the cylindrical portion 107d by a predetermined optical distance.

A needle holding mechanism that also has the function of the electrical characteristic measuring unit 119 is disposed outside the outer peripheral inclined surface 107i of the shielding unit 107a.
This needle holding mechanism has a function as a positioning unit 159 that holds the probe needle 109. The needle holding mechanism is electrically connected to an ESD unit 155 and an HV unit 153, which will be described later, and the electrical characteristics are measured by these.
In addition, when the probe needle 109 moves and comes into contact with the LED 101, the needle holding mechanism also has a function of moving and positioning the probe needle 109.
Thus, by arranging the needle holding mechanism outside the outer peripheral inclined surface 107i, the needle holding mechanism does not get in the way and it is not difficult to bring the first Fresnel lens 125a close to the LED 101.
That is, with such a configuration, the first Fresnel lens 125a can be brought close to the LED 101.

Each light receiving element of the CCD 105 receives light emitted from the LED 101.
Then, the light receiving element outputs an electric signal of the intensity (information) of the received light as an analog signal to the image processing unit 113 via the signal line 111.
The light information output from the CCD 105 is information in which the positions in the X direction (horizontal direction) and the Y direction (vertical direction) are specified, and can be referred to as light reception information (image information) as a surface.
Further, since the CCD 105 is focused on the LED 101 by the lens unit 123, the CCD 105 measures information (light emission information) on the light emission state of the LED 101.
The image processing unit 113 A / D converts this analog value from an analog value to a digital value.
Further, the image processing unit 113 performs image processing as necessary.
Then, the light amount information converted into the digital value is output to the tester 151 via the communication line (see also FIG. 5).
The image processing unit 113 is physically connected to the holder 107 via the spacer 117.

  FIG. 5 is an explanatory diagram of the outline of the light emission state measuring device 3.

The light emission state measuring device 3 includes a light receiving module 1 for a semiconductor light emitting element, an electrical characteristic measuring unit 119, a tester 151, and a display unit 152.
In the present embodiment, the light-receiving module 1 for a semiconductor light-emitting element includes a workpiece 102 (sample mounting table), a CCD 105, a holder 107, a signal line 111, an image processing unit 113, a communication line 115, a spacer 117, and a lens 123. .
However, all of these are not essential components of the light-receiving module 1 for semiconductor light-emitting elements, and it is sufficient to have at least the CCD 105 and the lens 123.
The electrical characteristic measurement unit 119 includes an HV unit 153, an ESD unit 155, a switching unit 157, and a positioning unit 159.

Each light receiving element of the CCD 105 receives light emitted from the LED 101.
Then, the light receiving element outputs an electric signal of the intensity (information) of the received light as an analog signal to the image processing unit 113 via the signal line 111.
The light information output from the CCD 105 is information in which the positions in the X direction (horizontal direction) and the Y direction (vertical direction) are specified, and can be referred to as light reception information (image information) as a surface.
That is, since the information output from the CCD 105 is light reception information as a surface, it can also be called image information. Therefore, the CCD 105 can be said to be a light receiving means, and more specifically, it can be said to be an imaging means.
Further, since the CCD 105 is focused on the LED 101 by the lens unit 123, the CCD 105 measures information (light emission information) on the light emission state of the LED 101.
The image processing unit 113 A / D converts this analog value from an analog value to a digital value. Further, the image processing unit 113 performs image processing as necessary.
Then, the light amount information converted into the digital value is output to the tester 151 via the communication line.

The probe needle 109 has a function of applying a voltage for causing the LED 101 to emit light by physically contacting the surface of the LED 101.
The probe needle 109 is positioned and fixed by a positioning unit 159.
If the positioning unit 159 is of a type in which the workpiece 102 moves, the positioning unit 159 has a function of holding the tip position of the probe needle 109 at a fixed position. Conversely, if the positioning unit 159 is of a type in which the probe needle 109 moves, the tip position of the probe needle 109 is moved to a predetermined position on the workpiece 102 on which the LED 101 is placed, and then the position is reached. Has the function of holding.

The HV unit 153 has a role of detecting various characteristics of the LED 101 with respect to the rated voltage by applying the rated voltage.
Normally, the CCD 105 measures the light emitted from the LED 101 in a state where the voltage from the HV unit 153 is applied.
Various characteristic information detected by the HV unit 153 is output to the tester 151.

The ESD unit 155 is a unit that inspects whether or not the LED 101 is electrostatically discharged by applying a large voltage to the LED 101 for a moment to cause electrostatic discharge.
The electrostatic breakdown information detected by the ESD unit 155 is output to the tester 151.

The switching unit 157 switches between the HV unit 153 and the ESD unit 155.
That is, the voltage applied to the LED 101 via the probe needle 109 is changed by the switching unit 157. And by this change, the inspection item of LED101 is each changed to the detection of the various characteristics in a rated voltage, or the presence or absence of an electrostatic breakdown.

The tester 151 receives input of image information output from the image processing unit 113, various electrical characteristic information detected by the HV unit 153, and electrostatic breakdown information detected by the ESD unit 155.
Then, the tester 151 analyzes and sorts the characteristics of the LED 101 from this input. That is, the tester 151 has a function as a control unit of the light emission state measuring device 3.
In particular, in the present embodiment, the tester 151 performs image processing and the like from image information as necessary, and detects (inspects and measures) a light emission state.
Further, the tester 151 analyzes and sorts the LEDs 101 according to the issue status.
For example, the tester 151 performs the classification that the LED 101 that does not have a certain performance should be discarded. Further, separation is performed for each light intensity (light quantity).
The physical separation is performed in a step after the inspection by the light emission state measuring device 3.

Further, the tester 151 displays the light emission status on a display unit (display or the like). Based on this display, the user may silently confirm.
In this case, there is an advantage that further necessary inspection / separation can be performed by the user.

  FIG. 6 is an explanatory diagram of the effect of this embodiment. FIG. 7 is a comparative example used when explaining the effect of the present embodiment.

In FIG. 6, not the probe needle 109 but the lead wire 101c supplies power to the LED 101 to emit light. Even in the case of the probe needle 109, substantially the same result is obtained.
In FIG. 6A, the LED 101 emits light by supplying power to the terminal 101b of the LED 101 through the lead wire 101c. The lens unit 123 is located in the vicinity of the LED 101. On the other hand, in the comparative example, the lens portion 123 is positioned in the vicinity of the CCD 105 as shown in FIG.
Image information as shown in FIG. 6B can be acquired by using the light emission state measuring device 3 of the present embodiment shown in FIG. On the other hand, only the image information as shown in FIG. 7B can be acquired by the method of the comparative example of FIG. In the method of FIG. 7A, an enlarged image as shown in FIG. 6B cannot be acquired (see FIG. 3). It is an image.
It can be easily understood by comparing FIG. 6B and FIG. 7B, but FIG. 6 can be said to be a higher resolution image.
It can also be seen that the light emission state measuring apparatus 3 of the present embodiment can obtain an image without the lead wire 101c.

<Second Embodiment>
The method of the present invention can also be applied to a semiconductor device that does not emit light. Even in these devices, it may be necessary to measure the appearance and the like, and in that case, the measurement is possible in the same manner.

<Effect of embodiment>
The light emission state measurement device 3 of the present embodiment is a light emission state measurement device 3 that receives light emitted from the LED 101 and measures the light emission state.
The light emission state measuring device 3 includes a CCD 105 that is disposed on the light emission central axis of the LED 101 and is opposed to the LED 101 and images the light emission state of the LED 101.
The lens unit 123 includes a lens unit 123 that receives light emitted from the LED 101 and emits the light toward the CCD 105.
In addition, the lens unit 123 is disposed between the LED 101 and the CCD 105, and is disposed closer to the LED 101 than the CCD 105.
Since it has such a structure, the light emission condition measuring apparatus 3 which can test | inspect the light emission condition and external appearance of LED101 itself with a simple structure can be obtained.

The lens unit 123 is disposed at a position where the LED 101 is positioned slightly far from the focal point of the lens unit 123 on the LED 101 side, and the CCD 105 is disposed at a position where a real image of the LED 101 is formed.
Since it has such a configuration, the state of the LED 101 can be imaged with high resolution by the CCD 105. Further, since the CCD 105 is completely in focus with the LED 101, the light emission state of the LED 101 can be measured by the CCD 105. Specifically, it is possible to determine which part of the LED 101 is not emitting light. Furthermore, if an optical filter or the like is used, the intensity and wavelength of the light can be detected for each part even if the part is emitting light.
Further, a wide range of light can be condensed on the CCD 105, and measurement in a short time is possible. Furthermore, it is possible to guide the CCD 105 with light in which the light emission direction of a portion of the LED 101 is directed in a direction different from the emission central axis.
In addition, substantially only the LED 101 can be imaged. It is also possible to measure the light emission state of the portion hidden behind the probe needle 109. The light hidden behind the probe needle 109 is measured by light passing through an optical path that is not blocked by the probe needle 109.

The lens portion 123 has a numerical aperture of 0.86 or more.
Since it has such a configuration, it is possible to cause the CCD 105 to receive light with a wide resolution and a wide angle of θ by being further enlarged, and to obtain image information excluding other than the LED 101.

An image processing unit 113 that processes image information captured by the CCD 105 and a display unit 152 that displays the image information as an image are provided.
Since it has such a structure, there exists an advantage that the test | inspection and classification which are further required by a user are attained.

The lens unit 123 includes a plurality of lenses.
With such a configuration, a high NA value can be easily obtained.

A lens arranged at a position closest to the LED 101 among at least a plurality of lenses is constituted by a Fresnel lens.
By having such a configuration, the first Fresnel lens 125a can be brought close to the LED 101.

  Further, the present invention is not limited to the above embodiment, and various changed structures and configurations may be performed.

<Definition etc.>
In the present invention, the light emission state refers to all information contained in light such as the presence / absence of light emission for each part, the intensity of light emitted in that part, and the wavelength of light emitted in that part.
The CCD 105 according to the embodiment is an example of an imaging unit in the present invention. That is, the imaging means may be anything as long as it can acquire light reception information as a surface.
The LED 101 is an example of a semiconductor light emitting element in the present invention. That is, the semiconductor light emitting element may be any element that emits light. Here, the light is not limited to visible light, and may be, for example, infrared rays or ultraviolet rays.
Furthermore, the lens unit 123 is an example of the lens unit of the present invention. That is, the lens unit 123 may be anything as long as it can refract light and enlarge an image. It may be composed of a plurality of lenses. Further, it is not necessary to be composed only of convex lenses.
In the present invention, the emission central axis is an axis that becomes the center of light when the semiconductor light emitting element emits light.

DESCRIPTION OF SYMBOLS 1 Light reception module for semiconductor light emitting elements 3 Light emission condition measuring apparatus 101 LED (semiconductor light emitting element)
105 CCD (imaging means)
113 Image processing unit 123 Lens unit 125a First Fresnel lens 151 Tester 152 Display unit

Claims (5)

A light emission state measuring device that directly receives light emitted from an LED and directly measures the light emission state.
An imaging unit that is disposed on the light emission central axis of the LED and is opposed to the LED, and that images the light emission state of the LED;
A lens unit that receives light emitted from the LED and emits the light toward the imaging unit;
The lens unit is disposed between the LED and the imaging unit, and is disposed closer to the LED than the imaging unit.
The lens unit includes a plurality of lenses, and at least a lens disposed at a position closest to the LED among the plurality of lenses is a light emission state measuring device configured by a Fresnel lens. The LED is a lens unit disposed at a position at a distance of 2 times the position from the slightly larger location than 1 times the distance of the focal point of the LED side of the lens unit, imaging means, this It is arranged at the position where the real image of LED is connected
Emitting state measuring device according to 請 Motomeko 1. The lens unit has its numerical aperture that is formed in less than 0.86
The light emission state measuring device according to claim 2 . An image processing unit for processing image information captured by the imaging unit;
Emitting state measuring device according to any one of claims 1 to 3, and a display unit for displaying the image information as an image. Wherein the outside of the light-emitting state measuring device, any one of claims 1-4 comprising a needle holding mechanism having a probe for applying a voltage to the cause LED to emit light in physical contact with the surface of the LED The light emission state measuring device according to item 1.