JP2012007951A - Measurement device for light distribution characteristics of light source - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measurement device for light distribution characteristics of a light source, the device that can obtain a sufficient angle resolution with a simple and compact device configuration.SOLUTION: A measurement device 1 for light distribution characteristics of a light source 11 repeats an operation of detecting intensity of light emitted from an emitting-side aperture 13b of an integrating sphere 13 using a light intensity detector 21 every time a fan-shaped rotational aperture 17 is rotated by a central angle. The light intensity detector 21 performs the detecting operation every time an aperture diameter of a variable aperture 15 is varied in accordance with a desired angle resolution, or every time at least one of the light source 11 and integrating sphere 13 is moved by a movement mechanism 19. The measurement device 1 then determines three-dimensional light distribution characteristics of the light source 11 using the detection result.

Description

  The present invention relates to an apparatus for measuring a light distribution characteristic that is a basic characteristic of a light source.

  Conventionally, in measuring the light distribution characteristics of a light source, it has been necessary to measure the light distribution characteristics in a wide solid angle range, for example, a solid angle range of a hemispherical coordinate system, for the intensity of light emitted from the light source. Specifically, scanning is performed around a light source with a measuring light receiver (light receiving element) using a three-dimensional goniophotometer or a goniophotometer. In that case, the light source is a point light source. It was necessary to make the distance between the light source and the light receiver large enough to be regarded as

  However, in such a conventional technique, a mechanism for scanning with a light receiver becomes large. In particular, when the size of the light source is large or when the angular resolution of light distribution is increased, it is necessary to further increase the distance between the light source and the light receiver. For this reason, the size of the device for driving the light receiver must be increased. Such an increase in the size of the apparatus accompanying the expansion of the measurement space leads to an increase in cost. In the conventional technique, the light receiver must be moved in two directions in order to measure the three-dimensional light distribution characteristic. The two directions referred to here are, for example, when the front direction of the light emitting surface is the Z axis, and the receiver is moved in the circumferential direction in which the receiver is rotated around the Z axis and in the direction of the Z axis. Axial direction.

  As a solution to such a problem, Patent Document 1 discloses a measuring apparatus in which a plurality of light receivers are arranged in advance at positions opposite to different radial angles with respect to the Z axis in the front direction of the light emitting surface. ing. In this apparatus, the light receiver moves only 360 degrees in one direction in the circumferential direction, but still requires a large space as a three-dimensional light distribution characteristic measuring apparatus.

  Thus, a photometric device with a small measurement space is disclosed in Patent Document 2. In this device, the optical axes of a plurality of luminance meters are arranged radially so that they intersect at one point (point P). Further, mirror surfaces corresponding to the individual luminance meters are arranged on an ellipse having the light source and the point P as focal points.

JP 2005-172665 A JP 7-294328 A

  However, in the photometric device described in Document 2, since the mirror surface is arranged on an ellipse as described above, the reflection angle of light varies depending on the position of the mirror surface. Therefore, the dependency of the reflectance on the incident angle becomes an error in light distribution measurement. In addition, since a plurality of luminance meters are arranged, there is a limit on the downsizing of the measuring apparatus.

  The present invention has been made in view of such a problem, and an object of the present invention is to provide a light distribution characteristic measurement device for a light source that can obtain a sufficient angular resolution while having a simple and space-saving device configuration. To do.

  In order to achieve such an object, the present invention is an apparatus for measuring the three-dimensional light distribution characteristics of a light source having a circular light emitting surface, and includes an incident side opening for introducing light from the light source into the inside. The integrating sphere formed with an exit side opening that is always emitted as light having the same exit azimuth regardless of the incident aperture angle, as a result of light diffused and reflected internally from the entrance side opening, A light intensity detector for detecting the intensity of light emitted from the exit side opening, a variable aperture provided in the entrance side opening of the integrating sphere, the aperture diameter being variable, and the entrance side opening of the integrating sphere At least one of the light source and the integrating sphere, which is provided immediately before or after the variable aperture and is rotatable about the apex of a fan-shaped opening having a central angle equal to a desired angular resolution, and the light source and the integrating sphere A moving mechanism capable of moving and changing a distance from the light source to the incident-side opening of the integrating sphere; variable control of an aperture diameter of the variable aperture; rotation control of the fan-shaped rotary aperture; and the moving mechanism A controller that controls the movement of at least one of the light source and the integrating sphere according to the above and the timing for detecting the light intensity by the light intensity detector, and the controller controls the variable aperture according to a desired angular resolution. Each time the aperture diameter is changed or at least one of the light source and the integrating sphere is moved by the moving mechanism, the intensity of the light emitted from the exit side opening of the integrating sphere is adjusted by the light intensity detector. The detection operation is repeated each time the fan-shaped rotation aperture is rotated by the central angle, and the detection result obtained is used. Obtaining a three-dimensional light distribution characteristic of the light source.

  In the light distribution characteristic measuring apparatus of the light source according to the present invention, the size of the aperture diameter of the variable aperture is gradually increased from the minimum diameter at a pitch based on a desired angular resolution, and within the light distribution characteristic measurement range. When the maximum diameter is reached, variable aperture control means for causing the variable aperture to repeat this operation, and whenever the size of the aperture diameter of the variable aperture reaches the maximum diameter, the moving mechanism causes the light source and the integrating sphere to At least one is moved in a direction approaching each other at a pitch based on the desired angular resolution, and a movement mechanism control unit that repeats this operation until the light source and the incident-side opening of the integrating sphere contact each other, the light source, and the integration Each time the sphere comes into contact with the incident side opening, the fan-shaped rotation aperture is rotated by the size of the central angle, and this operation is performed at the end within the light distribution characteristic measurement range. Fan-shaped rotation aperture control means that repeats until the aperture diameter of the variable aperture changes, the first detector that detects the size of the aperture diameter, and the fan-shaped rotation aperture rotates each time the fan-shaped rotation aperture rotates. And a second detector for detecting the position of the fan-shaped opening and a distance from the light source to the incident-side opening of the integrating sphere each time at least one of the light source and the integrating sphere moves. A third detector, and the light intensity detector that detects the intensity of light emitted from the exit-side opening of the integrating sphere each time one of the first to third detectors performs a detection operation; The size of the aperture of the variable aperture detected by the first detector, the position of the fan-shaped opening of the fan-shaped rotary aperture detected by the second detector, and detected by the third detector Said light source From the light intensity detected by the light intensity detector when the distance to the input aperture of al the integrating sphere and these are detected, and a data processing device for determining a three-dimensional light distribution characteristic of the light source.

  Furthermore, in the light distribution characteristic measuring apparatus for a light source according to the present invention, a direction in which at least one of the light source and the integrating sphere is moved by the moving mechanism is parallel to an optical axis direction of light emitted from the light source. The optical axis in the present invention is defined as a straight line that passes through the center of the light emitting surface of the light source and is perpendicular to the light emitting surface of the light source.

  Further, in the light distribution characteristic measuring apparatus of the light source according to the present invention, the variable aperture and the fan-shaped rotation aperture are moved to the incident side opening of the integrating sphere by at least one of the light source and the integrating sphere by the moving mechanism. It is provided so that it may become perpendicular | vertical with respect to the direction to do.

  Further, in the light distribution characteristic measuring apparatus of the light source according to the present invention, the center of the light emitting surface for emitting the light formed in the light source, the opening center of the variable aperture, and the rotation center of the fan-shaped rotation aperture are The moving mechanism is on a straight line parallel to the direction in which at least one of the light source and the integrating sphere moves.

  According to the present invention, it is possible to provide a light distribution characteristic measurement device for a light source that has a simple and space-saving device configuration and can obtain a sufficient angular resolution.

It is a section lineblock diagram of a light distribution characteristic measuring device of a light source concerning this embodiment. It is explanatory drawing of the coordinate system showing a light distribution characteristic. It is a figure showing the light distribution characteristic in a certain azimuth angle detected by the light distribution characteristic measuring apparatus of the light source which concerns on this embodiment. It is sectional drawing from a light source to a variable aperture.

  Hereinafter, embodiments will be described with reference to the drawings. As shown in FIG. 1, the light source three-dimensional light distribution characteristic measuring apparatus 1 according to this embodiment includes a light source 11 that is a measurement target, an integrating sphere 13 in which an incident side opening 13a and an emission side opening 13b are formed. The variable aperture 15, the fan-shaped rotation aperture 17, the moving mechanism 19, the light intensity detector 21, the first detector 23, the second detector 25, the third detector 27, and the controller 29. And a data processing device 31.

  In the light source 11, a circular light emitting surface 11 a is installed toward the incident side opening 13 a of the integrating sphere 13. Further, the diameter of the circular light emitting surface 11 a is smaller than the smaller one of the maximum diameter of the opening of the variable aperture 15 and the opening diameter of the incident side opening 13 a of the integrating sphere 13.

  The integrating sphere 13 repeats diffuse reflection inside the incident side opening 13a for introducing the light from the light source 11 and the light introduced from the incident side opening 13a, and as a result (introduced into the integrating sphere 13). It has an exit side opening 13b that always emits light having the same exit direction regardless of the incident aperture angle θ of the light.

  The variable aperture 15 is provided in the incident side opening 13a of the integrating sphere 13 and can change the size of the opening diameter.

  The fan-shaped rotary aperture 17 is provided so as to overlap the incident aperture 13a of the integrating sphere 13 with the variable aperture 15, and has a fan-shaped aperture having a central angle ω having a magnitude equal to a desired angular resolution (in an azimuth direction described later). It is possible to rotate around the vertex of the part. In addition, the radius of the fan-shaped opening of the fan-shaped rotating aperture 17 is larger than the maximum diameter of the opening of the variable aperture 15. The smaller the sector central angle ω, the higher the angular resolution (in the azimuth angle direction described later) can be measured.

  Note that the variable aperture 15 and the fan-shaped rotary aperture 17 are both in the direction in which at least one of the light source 11 and the integrating sphere 13 moves to the incident side opening 13a of the integrating sphere 13 by the moving mechanism 19 (that is, the optical axis direction). It is provided to be vertical.

  The moving mechanism 19 can move at least one of the light source 11 and the integrating sphere 13 to change the distance from the light source 11 to the incident-side opening 13 a of the integrating sphere 13.

  The light intensity detector 21 detects the light emitted from the exit side opening 13b of the integrating sphere 13 each time any one of the first detector 23, the second detector 25, and the third detector 29 is detected. Detect intensity.

  The first detector 23 detects the size of the opening diameter every time the size of the opening diameter of the variable aperture 15 changes.

  The second detector 25 detects the position of the fan-shaped opening every time the fan-shaped rotation aperture 17 rotates.

  The third detector 27 detects the distance from the light source 11 to the incident-side opening 13a of the integrating sphere 13 every time at least one of the light source 11 and the integrating sphere 13 moves.

  The controller 29 includes a variable aperture control unit 29a, a moving mechanism control unit 29b, and a fan-shaped rotation aperture control unit 29c.

  The variable aperture control unit 29a gradually increases the size of the aperture diameter of the variable aperture 15 at a pitch ΔAp based on a desired angle resolution (in the light distribution angle direction described later) calculated from the minimum diameter by a method described later. When the maximum diameter is reached within the light distribution characteristic measurement range, control is performed to cause the variable aperture 15 to repeat this operation.

  The movement mechanism control unit 29b calculates at least one of the light source 11 and the integrating sphere 13 by the movement mechanism 19 in a direction approaching each other by the movement mechanism 19 every time the opening diameter of the variable aperture 15 reaches the maximum diameter. Control is performed so as to move at a pitch ΔD based on a desired angular resolution (in the light distribution angle direction described later), and to repeat this operation until the light source 11 and the incident-side opening 13a of the integrating sphere 13 contact each other.

  The fan-shaped rotation aperture control unit 29c rotates the fan-shaped rotation aperture 17 by a central angle ω (with a size equal to the desired angular resolution) every time the light source 11 and the incident side opening 13a of the integrating sphere 13 contact each other. Is controlled until the fan-shaped rotary aperture 17 reaches the end within the light distribution characteristic measurement range.

  The data processing device 31 includes the size of the opening diameter of the variable aperture 15 detected by the first detector 23, the position of the fan-shaped opening of the fan-shaped rotary aperture 17 detected by the second detector 25, the third From the distance from the light source 11 detected by the detector 27 to the entrance-side opening of the integrating sphere 13 and the light intensity detected by the light intensity detector 21 when these are detected, The three-dimensional light distribution characteristic is obtained.

  The screen display device 33 displays the measurement result of the light distribution characteristic of the light source 11 derived by the data processing device 31.

  In obtaining light distribution characteristics in the present embodiment, as shown in FIG. 2, a plane that intersects the reference axis with the moving direction of the integrating sphere 13 and the light source 11 (the optical axis direction of the light source 11) as a reference axis. Each luminance is measured at an angle θ (hereinafter also referred to as a light distribution angle θ) on the (detection surface) and an inclination α (hereinafter also referred to as an azimuth angle α) of the plane. Further, the measurable angle range is set from the front to the side of the light source 11 (θ = 0 to 90 °) and the entire circumference (α = 0 to 360 °) in the circumferential direction. In the following, the detection azimuth α on the plane perpendicular to the moving direction of the integrating sphere 13 and the light source 11 corresponds to the rotation azimuth α of the fan-shaped rotation aperture 17 and the light distribution angle in the detection plane. The incident aperture angle θ of the light 11 introduced into the integrating sphere 13 corresponds to θ.

  Then, the measuring method of the light distribution characteristic of the light source 11 by the light distribution characteristic measuring apparatus 1 of the said structure is demonstrated. In measurement, the center of the light emitting surface 11 a of the light source 11, the opening center of the variable aperture 15, and the rotation center of the fan-shaped rotation aperture 17 are directions in which at least one of the light source 11 and the integrating sphere 13 is moved by the moving mechanism 19 (that is, light Adjust so that it is on a straight line parallel to the axial direction. Further, the moving mechanism 19 is always adjusted so that the moving direction of the light source 11 and the integrating sphere 13 is parallel to the optical axis direction of the light emitted from the light emitting surface 11 a of the light source 11.

  In the light distribution characteristic measuring apparatus 1, a part of the light emitted through the light emitting surface 11a of the light source 11 sequentially passes through the fan-shaped rotary aperture 17 and the variable aperture 15 provided in the incident side opening 13a of the integrating sphere 13, It is introduced into the integrating sphere 13 (see FIG. 1).

  The controller 29 introduces the diameter of the opening of the variable aperture 15 into the integrating sphere 13 by gradually widening from an infinitesimal pitch at a later-described pitch ΔAp calculated based on a desired light distribution angle resolution. The incident aperture angle θ of light from the light source 11 is increased by the desired light distribution angle resolution, and the intensity of light emitted from the exit side opening 13b of the integrating sphere 13 to the light intensity detector 21 each time (at each angle). Is detected. And the data processing apparatus 31 calculates | requires a relative light distribution intensity | strength by the method mentioned later using the detected result. In the above operation, the diameter of the opening of the variable aperture 15 is equal to the diameter of the incident side opening 13a of the integrating sphere 13 or is equal to or smaller than the diameter of the incident side opening 13a of the integrating sphere 13 and the variable aperture. Repeat until the maximum diameter of 15 is reached.

  Next, the controller 29 causes the moving mechanism 19 to gradually move at least one of the light source 11 and the integrating sphere 13 in a direction approaching each other at a pitch ΔD, which will be described later, calculated based on a desired light distribution angle resolution. As a result, the incident aperture angle θ of the light from the light source 11 introduced into the integrating sphere 13 is increased by the desired light distribution angle resolution, and each time (at each angle), the light intensity detector 21 receives the integrating sphere 13. The intensity of light emitted from the emission side opening 13b is detected. And the data processing apparatus 31 calculates | requires a relative light distribution intensity | strength by the method mentioned later using the detected result. The above operation is repeated until the incident side opening 13a of the integrating sphere 13 (the fan-shaped rotational aperture 17) contacts the light source 11, that is, until the incident opening angle θ to the integrating sphere 13 reaches 90 °.

  If the thus obtained light distribution intensity is plotted for each light distribution angle, a graph of the light distribution characteristic at a certain azimuth angle α as shown in FIG. 3 can be obtained.

  A series of operations as described above is performed every time the fan-shaped rotation aperture 17 is rotated by the central angle ω (azimuth resolution) until the end (for example, α = 360 °) is reached within the light distribution characteristic measurement range. It is possible to derive the light distribution characteristic over the entire circumference of the eleven.

  Here, a method of deriving the change pitch ΔAp of the opening diameter of the variable aperture 15 described above, which is used in the variable aperture control unit 29a, will be described with reference to FIG. The diameter of the light emitting surface 11a of the light source 11 is As, and the incident aperture angle of light from the light source 11 introduced into the integrating sphere 13 is θ (provided in the incident side aperture 13a of the integrating sphere 13). When the size of the aperture diameter of the variable aperture 15 is Ap and the distance from the light source 11 to the incident side aperture 13a of the integrating sphere 13 is D, the variable aperture is obtained from the geometrical relationship as shown in the following equation (1). A diameter Ap of 15 can be expressed as a function of θ.

  Ap = 2Dtanθ + As (1)

What we want to know here is the amount of change in the diameter Ap of the variable aperture 15 when the incident aperture angle θ of light from the light source 11 introduced into the integrating sphere 13 changes by a desired light distribution angle resolution θ _r. ΔAp, which can be expressed by equation (2) as follows.

If the value of the light distribution angular resolution θ _r , the incident aperture angle θ and the corresponding distance D from the light source 11 to the incident side aperture 13a of the integrating sphere 13 is substituted into this equation (2), the diameter of the variable aperture 15 The specific value of the change pitch ΔAp can be obtained.

  Next, a method for deriving the change pitch ΔD of the distance from the light source 11 to the incident side opening 13a of the integrating sphere 13 used in the moving mechanism control unit 29b will be described with reference to FIG. Assuming that the distance from the light source 11 to the incident side opening 13a of the integrating sphere 13 is D, the distance D can be expressed as a function of θ from the geometrical relationship as shown in the following equation (3).

What we want to know here is that from the light source 11 to the incident side opening 13a of the integrating sphere 13 when the incident opening angle θ of the light introduced into the integrating sphere 13 changes by the desired light distribution angle resolution θ _r . This is a change amount ΔD of the distance D, which can be expressed by the following equation (4).

If the values of the light distribution angle resolution θ _r , the incident aperture angle θ, the diameter Ap of the variable aperture 15 and the diameter As of the light emitting surface 11 a of the light source 11 are substituted into the equation (4), the integration from the light source 11 is performed. A specific value of the change pitch ΔD of the distance to the incident side opening 13a of the sphere 13 can be obtained.

Next, a method for deriving the relative light distribution intensity from the emission light intensity of the integrating sphere 13 detected by the light intensity detector 21 in the data processing device 31 will be described. When the incident aperture angle of light from the light source 11 to the integrating sphere 13 is θ, the light intensity I _θ detected by the light intensity detector 21 and the light distribution angle resolution θ _r from the incident aperture angle θ. The difference from the detected light intensity I _{θ + θr} at the increased angle corresponds to the radiant flux at the light distribution angle θ in the azimuth α specified by the sector rotation aperture 17. However, the light distribution characteristic is defined by the luminance for each light distribution angle, that is, the radiant flux per unit area. Therefore, it is necessary to _divide the difference in light intensity (I _{θ + θr} −I _θ ) by the amount of change in the light receiving solid angle (light receiving area) when the incident aperture angle θ changes by the light distribution angle resolution θ _r .

  The light receiving solid angle Ω is expressed by the following equation (5), where θ is the incident aperture angle of light from the light source 11 introduced into the integrating sphere 13 and ω is the sector center angle of the sector rotation aperture 17. Can be expressed as:

Therefore, the change amount ΔΩ of the light receiving solid angle when the incident aperture angle θ changes by a desired light distribution angle resolution θ _r can be expressed by the following equation (6).

Therefore, in order to obtain the light distribution intensity, the light intensity difference (I _{θ + θr} −I _θ ) can be divided by the amount of change ΔΩ of the light receiving solid angle as described above. Since it is a “relative” light distribution intensity, when the part that does not depend on θ is omitted from the above formula (6) as a constant, the following formula (7) gives the relative light distribution at the light distribution angle θ. The strength can be determined.

If the values of the light distribution angle resolution θ _r , the incident aperture angle θ, and the corresponding detection intensity I _θ (I _{θ + θr} ) are substituted into the equation (7), the relative distribution at the light distribution angle θ is obtained. The light intensity I _θr can be specifically obtained.

  As described above, according to the light distribution characteristic measuring apparatus according to the present embodiment, by arranging the integrating sphere between the light source and the detector, the detector (the detection surface thereof) is arranged in the light distribution direction of the light source. Since the position and orientation do not depend on each other, there is no need to move the detector (or its detection surface) or to install a plurality of detectors according to the measurement angle or measurement position as in the prior art. Therefore, the measuring device can be simplified and downsized. Further, the light distribution characteristic can be scanned only by changing the fan-shaped rotational aperture diameter and linearly moving one of the integrating sphere and the light source. Therefore, the driving mechanism is simplified. Furthermore, the light distribution angle resolution is not limited to the light receiving area of the detector that detects the light intensity, but only depends on the measurement accuracy of the distance from the integrating sphere to the light source and the measurement accuracy of the fan-shaped rotation aperture diameter. Measurement with high resolution is possible.

  That is, according to the present embodiment, it is possible to achieve a light distribution characteristic measuring device for a light source that has a simple and space-saving device configuration and can obtain a sufficient angular resolution.

  In order to make the present invention easy to understand, the configuration requirements of the embodiment have been described, but it goes without saying that the present invention is not limited to this.

  For example, in the light distribution characteristic measurement device of the light source according to the present embodiment, the light distribution angle θ is operated from the state where the light distribution angle θ is 0 ° so as to increase by a desired angular resolution, but the light distribution angle θ is 90 °. The reverse operation may be performed so as to decrease the desired angular resolution from the state.

  In the light distribution characteristic measuring apparatus for the light source according to the present embodiment, the distance from the light source 11 to the integrating sphere 13 is the pitch ΔD after the diameter of the opening of the variable aperture 15 is changed by the pitch ΔAp. Although the operation is performed to change, the operation is not limited to this, but the reverse operation, that is, after the distance from the light source 11 to the integrating sphere 13 is changed by the pitch ΔD, the diameter of the opening of the variable aperture 15 is changed. You may change by pitch (DELTA) Ap.

  Moreover, in the light distribution characteristic measuring apparatus of the light source according to the present embodiment, when the variable aperture 15 and the fan-shaped rotation aperture 17 are installed in the incident side opening 13a of the integrating sphere 13, either of them may be installed on the light source 11a side. Absent.

  Moreover, in the light distribution characteristic measuring apparatus of the light source according to the present embodiment, the light intensity detector 21 is not fixedly attached to the integrating sphere 13 but the exit side opening of the integrating sphere 13 through a bundle fiber or the like. You may comprise so that the light inject | emitted from 13b may be introduce | transduced into a light intensity detector. With this configuration, for example, when the light intensity detector is large and it is difficult to mount or move, it is possible to move only the integrating sphere 13 and improve convenience.

DESCRIPTION OF SYMBOLS 1 Light distribution characteristic measuring apparatus 11 Light source 11a Light emission surface 13 Integrating sphere 13a Incident side opening 13b Emission side opening 15 Variable aperture 17 Fan-shaped rotation aperture 19 Moving mechanism 21 Light intensity detector 23 First detector 25 Second detector 27 Third detector 29 Controller 29a Variable aperture control unit 29b Moving mechanism control unit 29c Fan-shaped rotation aperture control unit 31 Data processing device 33 Screen display device

Claims (5)

An apparatus for measuring the three-dimensional light distribution characteristics of a light source having a circular light emitting surface,
The incident side opening for introducing the light from the light source into the inside, and the light introduced from the incident side opening repeatedly diffused and reflected internally, so that the light is always emitted as light having the same emission direction regardless of the incident opening angle. An integrating sphere formed with an exit opening;
A light intensity detector for detecting the intensity of light emitted from the exit-side opening of the integrating sphere;
A variable aperture provided in the entrance-side opening of the integrating sphere and having a variable aperture diameter;
A fan-shaped rotary aperture that is provided immediately before or after the variable aperture of the incident-side aperture of the integrating sphere, and is rotatable about the apex of a fan-shaped aperture having a central angle equal to a desired angular resolution;
A moving mechanism capable of moving at least one of the light source and the integrating sphere to change a distance from the light source to the incident-side opening of the integrating sphere;
Variable control of the aperture diameter of the variable aperture, rotation control of the fan-shaped rotation aperture, movement control of at least one of the light source and the integrating sphere by the moving mechanism, and control of timing for detecting light intensity by the light intensity detector A controller to perform
The light intensity detector each time the controller changes the aperture of the variable aperture or moves at least one of the light source and the integrating sphere by the moving mechanism according to a desired angular resolution. The operation of detecting the intensity of the light emitted from the exit-side opening of the integrating sphere is repeated each time the fan-shaped rotation aperture is rotated by the central angle, and using the obtained detection result, the three-dimensional A light distribution characteristic measuring apparatus characterized by obtaining a light distribution characteristic. The opening diameter of the variable aperture is gradually increased from the minimum diameter at a pitch based on the desired angular resolution, and when the maximum diameter is reached within the light distribution characteristic measurement range, the variable aperture is repeatedly operated. Aperture control means,
Each time the opening diameter of the variable aperture reaches the maximum diameter, the moving mechanism moves at least one of the light source and the integrating sphere at a pitch based on a desired angular resolution in a direction in which the light source and the integrating sphere approach each other. Moving mechanism control means that repeats until the light source and the incident-side opening of the integrating sphere contact each other,
Each time the light source and the incident-side opening of the integrating sphere contact each other, the fan-shaped rotation aperture is rotated by the size of the central angle, and this operation is repeated until the end is reached within the light distribution characteristic measurement range. Aperture control means,
A first detector that detects the size of the aperture diameter each time the aperture size of the variable aperture changes;
A second detector for detecting the position of the fan-shaped opening each time the fan-shaped rotation aperture rotates;
A third detector for detecting a distance from the light source to the incident side opening of the integrating sphere each time at least one of the light source and the integrating sphere moves;
The light intensity detector that detects the intensity of light emitted from the exit side opening of the integrating sphere each time any one of the first to third detectors performs a detection operation;
The size of the aperture of the variable aperture detected by the first detector, the position of the fan-shaped opening of the fan-shaped rotary aperture detected by the second detector, and detected by the third detector A data processing device for obtaining a three-dimensional light distribution characteristic of the light source from the distance from the incident light source to the entrance-side opening of the integrating sphere and the light intensity detected by the light intensity detector when these are detected The light distribution characteristic measurement device for a light source according to claim 1, wherein:   The light source arrangement according to claim 1 or 2, wherein a direction in which at least one of the light source and the integrating sphere moves by the moving mechanism is parallel to an optical axis direction of light emitted from the light source. Optical property measuring device.   The variable aperture and the fan-shaped rotation aperture are provided in the incident side opening of the integrating sphere so as to be perpendicular to a direction in which at least one of the light source and the integrating sphere moves by the moving mechanism. The light distribution characteristic measuring apparatus for a light source according to any one of claims 1 to 3.   At least one of the light source and the integrating sphere is moved by the moving mechanism at the center of the light emitting surface for emitting light formed on the light source, the opening center of the variable aperture, and the rotation center of the fan-shaped rotating aperture. The light distribution characteristic measuring apparatus for a light source according to any one of claims 1 to 4, wherein the light distribution characteristic measuring apparatus is on a straight line parallel to the direction.

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