JP2008070198A - Apparatus and method for measuring light radiation pattern of light-emitting body - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a measuring apparatus capable of measuring a precise light radiation pattern (light distribution pattern), irrespective of the angle of arrangement of a light-emitting body, with respect to a detection means. <P>SOLUTION: This light radiation pattern measuring apparatus for the light-emitting body is equipped with a polychrometer 108 for detecting the light of the light-emitting body 150 arranged in a darkroom 114, and a θ-stage 124 capable of changing the angle of arrangement of the emitting body 150, with respect to the polychrometer 108 and is so constituted that the detection area by the polychrometer 108 always includes the whole light-emitting part of the light-emitting body 150, irrespective of the angle of arrangement of the light-emitting body 150. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a light emission pattern measuring device and a measuring method for a light emitter.

  In the case of a surface emitting device such as an organic EL element, it is widely known that the light emission pattern (light distribution pattern) is usually approximated to a Lambertian distribution.

  Since this distribution can be defined by an angle (referred to as a radiation angle) θ from the normal direction (also referred to as the front direction) of the light emitting surface, for example, the luminance of the light emitting surface with a detector disposed only in the normal direction of θ = 0. Is applied to the following distribution equation (1) to estimate the luminance (I) at the angle θ and the value of the luminous flux that is the spatial sum, such an apparatus: Is already commercially available.

    I = Io cos θ (1)

  Here, Io is the light emission intensity in the normal direction (front direction: θ = 0).

  In recent years, in order to improve the energy efficiency of light-emitting elements, the device structure and materials used in the elements have been devised, and the light emission pattern deviates from the Lambertian distribution, for example, directivity is in the front direction. It may become strong or weak in the front direction. In such a case, the value estimated on the assumption of the Lambertian distribution does not necessarily indicate an accurate value.

  On the other hand, a method for directly measuring the light emission pattern of the light emitting element has also been proposed. For example, in Patent Document 1, as shown in FIG. 3, the condensing lens 6 side (that is, the detection unit side) is fixed, and the light emitting unit 4 of the electric light emitting element 3 is rotated by the rotary stage 2 to collect light. It is described that the measurement is performed while the arrangement angle of the light emitting unit 4 with respect to the lens 6 is displaced, and such an apparatus is also commercially available.

JP 2002-107268 A

  As is apparent from FIG. 3, conventionally, only a part of the light emitting unit 4 in the electroluminescent element 3 is detected (measured), including the measuring device described in Patent Document 1. However, it has been found that this method has a problem that the measurement result does not necessarily become an accurate value for the reason described later (comparison under the same conditions is not possible).

  It is an object of the present invention to provide a measuring apparatus and method for solving such problems and measuring an accurate light radiation pattern regardless of the arrangement angle of the light emitter.

  The present invention relates to light emission of a light emitter comprising: detection means for detecting light of a light emitter arranged in a test space; and a stage unit capable of changing an arrangement angle of the light emitter relative to the detection means. In the pattern measuring device, the above-described problem is solved by adopting a configuration in which the detection area by the detection means always includes the entire light emitting portion of the light emitter regardless of the arrangement angle of the light emitter. is there.

  The inventor rotates the electroluminescent element 3 having the light emitting part 4 by the rotary stage 2 when only a part of the light emitting part 4 in the electroluminescent element 3 is detected (measured) as in the conventional example. Then, it was found that the area (area of the light emitting unit 4) that is substantially detected (measured) differs depending on the arrangement angle (S5 <S6 <S7).

  Therefore, the inventor adopts the above-described configuration so that even when the arrangement angle of the light emitter is displaced, the entire light emitter (the light emitting portion thereof) can always be detected, and the substantial detection is performed according to the arrangement angle. The range (detection area) is prevented from changing.

  Furthermore, an optical fiber that receives the light of the light emitter arranged in the test space and guides it to the detecting means is provided, and a light receiving area by the optical fiber is always provided regardless of the arrangement angle of the light emitter. If it is set as the structure which includes the whole light emission part of the said light-emitting body, it will become possible to isolate | separate test space and a detection means. Thereby, for example, it becomes easy to place the test space under special conditions (dark room, high temperature, high pressure, etc.).

  If the detecting means is constituted by a polychromator, it is possible to measure the radiation angle dependency of the spectrum of the illuminant, and to accurately measure the radiation pattern characteristics of the luminance / chromaticity coordinates.

  Further, when an organic electroluminescence element is measured as a light emitter, it is possible to easily and accurately measure the width of the viewing angle (light emission pattern characteristics) that is a feature of the organic electroluminescence element.

  In another aspect of the present invention, an optical fiber that receives light from a light emitter disposed in the test space and guides the light to the outside of the test space, and light detected by the optical fiber is detected. A light emission pattern measuring method for a light emitter using a measuring device comprising a detecting means and a stage unit capable of displacing the arrangement angle of the light emitter with respect to the optical fiber, wherein the optical fiber always uses the optical fiber during measurement. It is also possible to grasp as a light emission pattern measurement method of a light emitter characterized in that the arrangement angle of the light emitter is displaced so that the entire light emitting portion of the light emitter is included in the light receiving area.

  By applying the present invention, the light emission pattern (light distribution pattern) can be accurately measured regardless of the arrangement angle of the light emitter with respect to the detection means.

  Hereinafter, an example of an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

  FIG. 1 is an overall configuration diagram of a light emission pattern measuring apparatus 100 as an example of an embodiment of the present invention, and FIG. 2 shows the relationship between an imaging area and a light emitter of the light radiation pattern measuring apparatus 100 according to the present invention. FIG.

  The light emission pattern measuring apparatus 100 includes a dark room 114 as a test space, an optical fiber 102 capable of guiding light from the inside of the dark room 114 to the outside, and light guided to the outside of the dark room 114 by the optical fiber 102. Detection means (details will be described later) and a control PC 140 for controlling the entire measurement apparatus.

  Inside the dark room 114, which is a test space, a light emitter 150 to be tested is arranged. As the light emitter 150, various light emitters such as an organic electroluminescence (hereinafter simply referred to as “organic EL”) element and an LED can be assumed. In the case of an organic EL element, it is possible to easily and accurately measure the width of the viewing angle (light emission pattern characteristics) that is a feature of the organic EL element. The light emitter disposed in the dark room 114 can be adjusted to an accurate measurement position by the Z stage 120 and the XY stage 122. Further, the θ stage 124 can freely displace the arrangement angle θ of the light emitter (the arrangement angle θ with respect to the detection means described later). In addition, a DC power supply 130 is provided outside the dark room 114, and power can be supplied from the DC power supply 130 to the light emitter 150. The Z stage 120, the XY stage 122, and the θ stage 124 described above are accurately controlled by a stage controller 126.

  The optical fiber 102 is disposed so as to face the light emitting surface of the light emitter 150 disposed in the dark room 114. The optical fiber 102 is fixed after being accurately positioned by a holder (not shown), for example. The optical fiber 102 can capture the entire light emitting portion 151 of the light emitter 150 disposed in the dark room 114 via an optical lens or the like as necessary (see FIG. 2). That is, the optical fiber 102 is arranged so that the entire light emitting portion 151 of the light emitter 150 is within the light receiving area of the optical fiber 102.

  The optical fiber 102 is connected to the polychromator 108 via the shutter 104 so that the spectral characteristics of the light emitter 150 can be transmitted to the control PC 140. An I / O unit 106 is connected to the shutter 104, and the opening and closing of the shutter 104 is controlled. Further, the I / O unit 106 is controlled by the control PC 140. The stage controller 126 described above is also controlled by the control PC 140.

  In this embodiment, the shutter 104 and the I / O unit 106 are integrated to form a detection mechanism as a whole in addition to the polychromator 108 that is a detection means.

  Next, the operation of the light emission pattern measuring apparatus 100 will be described.

  After the illuminant 150 to be measured is installed in the dark room 114, the illuminant 150 is adjusted to an accurate measurement position by the Z stage 120 and the XY stage 122. Further, the θ stage 124 makes the arrangement angle θ with respect to the input side end face of the optical fiber 102 be 90 ° (that is, the input side end face of the optical fiber 102 exists in front of the light emitter 150). adjust.

  Next, electric power is supplied from the DC power supply 130 to the light emitter 150 to cause the light emitter 150 to emit light. At this stage, the shutter 104 is closed. Subsequently, the shutter 104 is opened and the θ stage 124 is operated to gradually displace the arrangement angle θ of the light emitter 150 (for example, ± 90 °) and emit light at every predetermined arrangement angle θ (for example, 1 °). The emission intensity of the body 150 is measured. If the emission intensity is measured at all the arrangement angles θ, data as a light emission pattern (light distribution pattern) of the light emitter 150 can be acquired.

  At this time, in the light emission pattern measuring apparatus 100, the light receiving area (detection area of the polychromator 108) α of the optical fiber 102 always captures the entire light emitting portion 151 of the light emitter 150. That is, as shown in FIG. 2A, the entire light emitting portion 151 is within the light receiving area α of the optical fiber 102 when the arrangement angle θ of the light emitting portion 151 of the light emitter 150 is 0 °. Further, as shown in FIG. 2B, even when the arrangement angle θ of the light emitting unit 151 is 45 °, the entire light emitting unit 151 is contained in the light receiving area α. Further, as shown in FIG. 2C, even when the arrangement angle θ of the light emitting unit 151 is 60 °, the entire light emitting unit 151 is within the light receiving area α.

  As described above, the measurement is made substantially by the fact that the light emitting portion 151 of the light emitter 150 is always present in the light receiving area α regardless of the arrangement angle θ of the light emitter 150 (the light emitting portion 151). The area of the light emitting unit 151 does not change (S1 = S2 = S3), and accurate measurement under the same conditions becomes possible.

  In the present embodiment, the test space and the detection means are physically separated by connecting with an optical fiber. By adopting such a configuration, it was easy to make the test space into special conditions (dark room, high temperature, high pressure, etc.). In addition, there is a merit that the design freedom of each of the test space and the detection means is increased. Of course, it is possible to adopt a configuration in which the test space and the detection means are integrated without using an optical fiber.

  The present invention not only measures the light emission pattern of light emitters such as so-called flat display panels such as organic EL, liquid crystal displays, plasma displays, and electronic paper, but also has a highly directional light emitter (such as an LED). ) Can be widely used as a light radiation pattern measuring device.

1 is an overall configuration diagram of a light radiation pattern measuring apparatus 100 that is an example of an embodiment of the present invention. The figure which showed the relationship between the imaging area (optical fiber light-receiving area) of the optical radiation pattern measuring apparatus 100 concerning this invention, and a light-emitting body. Overall configuration diagram of measuring apparatus described in Patent Document 1 The figure which showed the relationship between the imaging area of the measuring apparatus described in patent document 1, and a light emission part (light-emitting body).

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 ... Light emission pattern (light distribution pattern) measuring apparatus 102 ... Optical fiber 104 ... Shutter 106 ... I / O unit 108 ... Polychromator (detection means)
114 ... Dark room (test space)
120 ... Z stage 122 ... XY stage 124 ... θ stage 126 ... stage controller 130 ... DC power supply 140 ... control PC
150 .. Light emitter (organic EL element)
θ ... Arrangement angle

Claims (5)

A light emission pattern measuring device for a light emitter, comprising: a detection means for detecting light of a light emitter arranged in a test space; and a stage unit capable of displacing an arrangement angle of the light emitter relative to the detection means. There,
Regardless of the arrangement angle of the light emitter, the detection area by the detection means always includes the entire light emitting portion of the light emitter. In claim 1,
Furthermore, an optical fiber that receives the light of the light emitter disposed in the test space and guides it to the detection means,
Regardless of the arrangement angle of the light emitter, the light receiving area by the optical fiber always includes the entire light emitting portion of the light emitter. In claim 1 or 2,
The light emitting pattern measuring device for a light emitter, wherein the detecting means is a polychromator. In any one of Claims 1 thru | or 3,
The said light-emitting body is an organic electroluminescent element. The light emission pattern measuring device of a light-emitting body characterized by the above-mentioned. An optical fiber that receives light from a light emitter disposed in the test space and guides the light to the outside of the test space, detection means for detecting the light guided by the optical fiber, and the light emitter for the optical fiber A stage unit capable of displacing the arrangement angle of the light emitting pattern measurement method of the illuminant using a measuring device comprising:
The method of measuring a light emission pattern of a light emitter, wherein the arrangement angle of the light emitter is displaced so that the entire light emitting portion of the light emitter is always included in a light receiving area of the optical fiber during measurement.

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