JP2008076126A - Photometric device and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photometric device and method which automatically and continuously measures the radiation output and the wavelength characteristic, etc. of a light emitting element. <P>SOLUTION: The photometric device comprises an integrating sphere having a highly diffusive inner wall with high optical reflectance of a split constitution of an element holding part 1 and a measurement main body 2, wherein a light receiving element disposed in the measurement main body 2 receives a radiation from a light emitting element disposed in the element holding part 1. The device also includes: a transporting part which moves the element holding part 1 toward the measurement main body 2 almost integrating both parts prior to the measurement operation, while it moves the element holding part 1 away from the measurement main body 2 when a measuring operation is finished; and an operation control part which makes the light emitting element emit light at the measurement operation and makes the light receiving element receive a diffuse wave after having almost integrated the element holding part 1 with the measurement main body 2. Light amount of the light emitting element held in the element holding part 1 and sequentially transported is continuously measured by repeating the operation of the transporting part and the operation control part. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a photometric device and a photometric method that can automatically measure the radiation output, wavelength characteristics, and the like of a light emitting element.

Manufacturers of light emitting elements such as light emitting diodes and laser diodes need to evaluate characteristics such as luminous intensity Iv (Candela), luminous flux Φv (Lumen), luminance Lv (cd / m ² ) in the final inspection process. In addition, the wavelength characteristic of the radiation intensity for each wavelength also becomes a problem.

  However, the light emitting element has directivity in the radiation intensity, and it is slightly different for each element, so that it is difficult to automatically perform the characteristic inspection.

In addition, although a measuring apparatus using an integrating sphere for smoothing directivity has been proposed (Patent Document 1 and Patent Document 2), none of them can realize continuous characteristic inspection.
No. 2003-297844 2002-318156

  The present invention has been made in view of these problems, and an object of the present invention is to provide a photometric device and a photometric method capable of automatically and continuously measuring the radiation output and wavelength characteristics of a light emitting element.

  In order to achieve the above object, the invention according to claim 1 is configured such that an integrating sphere having a high light reflectivity and a highly diffusible inner wall is divided into an element holding part and a measurement main part, and is arranged in the element holding part. The photometric device receives the radiated light from the light emitting element received by the light receiving element arranged in the measurement main body part, and moves the element holding part toward the measurement main body part prior to the measurement operation. On the other hand, when the measurement operation is completed, the light-emitting element is moved during the measurement operation after the transfer unit that moves the element holding unit away from the measurement main body unit and the element holding unit are substantially integrated with the measurement main unit when the measurement operation is completed. The element holding unit by repeating the operations of the transport unit and the operation control unit, and an operation control unit that causes the light receiving element to receive the diffuse reflection wave diffused by the inner wall of the integrating sphere. Held in order Is configured to measure the emitted light of the light emitting elements come being continuously.

  Here, preferably, a light-shielding member is arranged on a straight line from the light-emitting element to the light-receiving element, and is configured to shield direct waves during the measurement operation. Moreover, it is preferable that the measurement main body portion is provided with a movable portion that moves the conducting member and contacts the light emitting element prior to the measurement operation. Moreover, it is preferable that a fiber cable for transmitting light emitted from the light emitting element to the wavelength meter is attached to the measurement main body.

  According to a fourth aspect of the present invention, an integrating sphere having a high light reflectivity and a highly diffusive inner wall is divided into an element holding part and a measurement main part, and the emitted light from the light emitting element arranged in the element holding part Is received by a light receiving element disposed in the measurement main body, and prior to the measurement operation, the element holding portion in which the light emitting element is disposed is moved toward the measurement main body so that both are substantially omitted. A preparatory step for integration, a measurement step for causing the light-emitting element to emit light, and a diffused reflected wave from the inner wall received by the light-receiving element; and when the measurement step is completed, the element holding unit is removed from the measurement main body unit. And having a transition step of disposing another light emitting element on the element holding portion, and repeating the preparation step, the measurement step, and the transition step in this order, thereby emitting light from a plurality of the light emitting elements. Continuously It is to be measured.

  In the present invention described above, the integrating sphere is divided into the measurement main body part and the element holding part, and one of them is configured to be movable, so that the radiation output, wavelength characteristics, etc. of the light emitting element are automatically and continuously measured. be able to.

  Hereinafter, the present invention will be described in detail based on examples. FIG. 1 illustrates a schematic configuration of a photometric device according to an embodiment. This photometric device is configured such that an element holding unit 1 that holds a light emitting element such as a light emitting diode and a measurement main body 2 in which a plurality of photometric instruments are arranged can be divided to form an integrating sphere as a whole. .

  Here, the integrating sphere means a sphere having a spherical inner wall formed with a reflectance of about 100%. In this embodiment, when measuring light in a wavelength band of about 300 nm to 1300 nm, the spherical inner wall is coated with barium sulfate having a predetermined thickness. On the other hand, when measuring light with a wavelength band of 250 nm to 2500 nm, the inner wall is made by compacting PTFE (polytetrafluoroethylene) powder, and when measuring the infrared wavelength band of 1 μm to 2 μm, Gold plating is preferred.

  In any case, since the integrating sphere has a highly reflective inner wall, when a light source is arranged inside the integrating sphere, the emitted light from the light source is diffusely reflected by the highly reflective inner wall, and this diffuse reflected light is Then, it repeatedly hits the inner wall of the integrating sphere and is diffused. As a result, the directivity of the radiated light is integrated, and almost uniform brightness can be obtained regardless of the measurement position in the integrating sphere.

  Since this measurement value is proportional to the total light amount of the light source, the light amount of the light source to be measured can be specified by calibrating with the reference output value from the reference light source (master work).

  As shown in FIG. 1, the element holding part 1 and the measurement main body part 2 are configured by dividing an integrating sphere by a horizontal cut surface CUT, and in this embodiment, the horizontal cut surface CUT is a diameter R of the integrating sphere. It is formed at a height position of about 15%.

  The element holding unit 1 reciprocates in the horizontal plane in the direction of arrow a in FIG. 2 and reciprocates in the vertical plane in the direction of arrow b, and the lower integrating sphere 4 cut by the horizontal cut surface CUT, It consists of

  The bottom of the lower integrating sphere 4 is opened and fixed to the inspection table 3, and a mounting table 5 on which a measurement object WK (sample work) can be placed is provided on the bottom of the lower integrating sphere 4. ing. The mounting table 5 is configured so that a master work MS for calibration processing can also be mounted. The measurement object WK is, for example, a light emitting diode or a laser diode.

  Prior to the measurement work, the measurement object WK is placed on the mounting table 5 by the robot mechanism. When the measurement work is completed, the measurement object WK is replaced with the next measurement object WK by the robot mechanism. On the other hand, the master work MS is merely arranged on the mounting table 5 at the time of calibration work once every several days or months, and it is not necessary to use the master work at the time of measurement work. That is, the master work MS in FIG. 2 is only described for convenience.

  The measurement main body 1 is as shown in FIG. 1, and includes a first detection unit 6 and a second detection unit 7A that face each other on the horizontal center line of the integrating sphere, and a third detection unit 7B that is positioned on the top of the vertical center line. Is provided. The 1st detection part 6 is a part which measures the light quantity of a measuring object, and specifically, the photodiode is arrange | positioned. On the other hand, the second detection unit 7A and the third detection unit 7B constitute a part of the wavelength meter, and the two detection units 7A and 7B are arranged with the end portions of the fiber cables reaching the wavelength meter. . In this embodiment, since two detection units are provided, any one can be selected and used as necessary. In addition, since the diffusion plate which has translucency is arrange | positioned at the front-end | tip of detection part 7A, 7B, the function of an integrating sphere is not inhibited.

  In the measurement main body 1, a light shielding plate 8 that shields direct light from the measurement object WK and the master work MS is disposed at an intermediate position between the first detection unit 6 and the mounting table 5. Therefore, there is no possibility that the measurement target light is incident on the first detection unit 6 as direct light.

  Below the light shielding plate 8, there is provided a movable portion 10 for moving the probe needle 9 up and down. During the measurement operation, the movable unit 10 is lowered to bring the probe needle 9 into contact with the energization terminal of the measurement object WK. Then, due to the contact with the probe needle 9, the measurement object is energized, and radiated light is emitted from the measurement object WK. This radiated light has directivity and the intensity varies depending on the radiation direction. However, since the radiated light is repeatedly reflected on the inner wall of the integrating sphere, the radiant intensity is constant regardless of the light receiving position.

  By the way, since the photometric device of the present embodiment is configured by dividing the integrating sphere, the inspection light leaks from the gap δ generated on the opposing surface of the element holding unit 1 and the measurement main body unit 2 or the gap generated in the movable unit 10. There are harmful effects. Therefore, as shown in FIG. 3, it is preferable to provide a light shielding piece 11 in the movable portion 10.

  Moreover, it is preferable to provide a superposition part also about the opposing surface of the element holding | maintenance part 1 and the measurement main-body part 2. FIG. In FIG. 3, the lower end portion 2a of the measurement main body 2 is bent, and the gap δ substantially disappears (δ = 0) during the measurement operation in which the element holding portion 1 is raised to the limit position. However, in this embodiment, since the calibration process by the master work MS is provided, if the gap is suppressed to 0.5 mm to 1 mm, as shown in FIG. Can be eliminated.

  Next, a method of using the photometric device having the above configuration will be described.

  First, the measurement target WK is attached to the element holding unit 1 by the robot mechanism, and the element holding unit 1 is moved to a position below the measurement main body 2 based on the operation of the horizontal transfer mechanism (arrow a in FIG. 2).

  Thereafter, based on the operation of the vertical transport mechanism, the element holding unit 1 is raised and stopped at a position substantially in contact with the facing surface of the measurement main body unit 2 (arrow b in FIG. 2). In this state, the gap δ between the facing surfaces of the element holding portion 1 and the measurement main body portion 2 is managed to be about 1 to 0.5 mm.

  Subsequently, the movable part 10 is lowered and the probe needle 9 is brought into contact with the measurement object WK. Then, since the measuring object WK emits light, the amount of the emitted light is measured by the photodiode PD of the first detector 1. Further, the spectral sensitivity characteristic is also measured by the detection unit 7. Since the radiated light is repeatedly reflected on the inner wall of the integrating sphere, a value proportional to the integrated value of the radiated light is measured.

  Since the measurement process is completed as described above, next, after the movable unit 10 is raised, the element holding unit 1 is lowered based on the operation of the vertical transport mechanism. Further, the element holding unit 1 is retracted to the origin position based on the operation of the horizontal transport mechanism. And while removing the measuring object which finished the measurement process, another measuring object is attached, and said operation | movement is repeated again.

  Thus, according to the present embodiment, the light quantity of the light emitting element can be accurately measured, and this inspection process can be completely automated.

  As mentioned above, although the Example of this invention was described concretely, the concrete description content does not limit this invention at all. For example, in the embodiment of FIG. 1, the probe needle 9 is configured to be movable, but a fixed conducting member may be provided in the element holding portion 1 without providing the probe needle 9.

  In this case, since the movable part 10 does not exist, it is not necessary to provide the light shielding piece 11, and there is no possibility that the radiated light of the measurement object leaks from the gap of the movable part 10. In the configuration in which the movable unit 10 is not provided, the conductive member is also brought into contact with the measurement object when the measurement object WK is held on the mounting table 5. Therefore, from the viewpoint of simplicity, the energization operation to the measurement object WK may be started prior to the measurement operation.

  As mentioned above, although the Example of this invention was described concretely, the concrete description content does not specifically limit this invention. For example, in FIG. 1, two detection ports for the wavelength meter are provided. However, since only one location is usually used, it is sufficient to provide only one of the detection ports. In addition, it has been explained that a light-transmitting diffuser is placed at the detection port. However, if the time required for measurement is low because the amount of light from the measurement object is weak, the wavelength distribution should not be significantly affected. After confirming the above, it may be configured to receive direct light.

1 schematically illustrates the configuration of a photometric device according to an embodiment. It is a perspective view which shows a part of FIG. It is a perspective view which shows another part of FIG.

Explanation of symbols

WK Light emitting element 1 Element holding part 2 Measurement main body part 8 Light shielding member

Claims (5)

An integrating sphere having a high light reflectivity and a highly diffusive inner wall is divided into an element holding part and a measurement main part, and the emitted light from the light emitting element arranged in the element holding part is arranged in the measurement main part. A photometric device that receives light received from
Prior to the measurement operation, the element holding unit is moved toward the measurement main body unit so that the two are substantially integrated.On the other hand, when the measurement operation is completed, the conveyance unit for moving the element holding unit away from the measurement main body unit,
After the element holding part is substantially integrated with the measurement main body part, an operation control part that causes the light emitting element to emit light during a measurement operation and receives the diffuse reflected wave diffused on the inner wall of the integrating sphere by the light receiving element; Have
A photometric device configured to continuously measure the emitted light of the light emitting elements held by the element holding unit and sequentially conveyed by repeating the operations of the transfer unit and the operation control unit. The photometric device according to claim 1, wherein a light shielding member is disposed on a straight line extending from the light emitting element to the light receiving element, and shields a direct wave during a measurement operation. 3. The photometric device according to claim 1, wherein the measurement main body is provided with a movable portion that moves a conductive member to contact the light emitting element prior to a measurement operation. The photometric device according to any one of claims 1 to 3, wherein a fiber cable for transmitting light emitted from a light emitting element to a wavelength meter is attached to the measurement main body. An integrating sphere having a high light reflectivity and a highly diffusive inner wall is divided into an element holding part and a measurement main part, and the emitted light from the light emitting element arranged in the element holding part is arranged in the measurement main part. A photometric method received by a light receiving element
Prior to the measurement operation, the preparatory step of moving the element holding part on which the light emitting element is arranged toward the measurement main body part so that both are substantially integrated,
Then, a measurement step of causing the light emitting element to emit light and receiving the diffuse reflected wave from the inner wall by the light receiving element;
When the measurement step is completed, the device holding unit is moved away from the measurement main body unit, and another light emitting element is arranged in the device holding unit,
A photometric method in which the preparation step, the measurement step, and the transition step are repeated in this order to continuously measure the emitted light of the plurality of light emitting elements.

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