JP4932045B1 - Light source inspection device - Google Patents

Abstract

An object of the present invention is to provide an inspection device for a light source that can easily and accurately measure the optical performance of the light source using an integrating sphere.
An inspection apparatus for a light source according to the present invention includes an integrating sphere provided with an attachment portion to which a light source to be inspected can be attached, and an emission port for emitting light toward the outside. A photometric means for measuring a reflected light beam of a photometric area in a certain range on the inner circumferential surface of the opposing integrating sphere from an emission port; and a baffle disposed between the photometric area and the mounting portion. The baffle prevents the light emitted from the light source from directly entering the photometric area, and the photometric means can photometrically measure the photometric area, thereby reducing the difference in the photometric results due to the mounting condition of the light source in the mounting section. The optical performance of the light source can be measured easily and accurately.
[Selection] Figure 2

Description

  The present invention relates to a light source inspection apparatus, and more particularly to a light source inspection apparatus particularly suitable for inspecting a light source such as a light emitting diode (LED).

  When a light emitting diode is shipped from a manufacturing factory, a final inspection is performed to evaluate optical performance such as luminous intensity, luminous flux, and luminance. In evaluating the optical performance of such an LED, a light source inspection device having an integrating sphere is used (see, for example, JP-A-2008-76126).

  In this conventional light source inspection apparatus, as shown in FIG. 4, an integrating sphere 110 having an inner peripheral surface that reflects a light beam, and an emitted light beam of a light source to be inspected enter the integrating sphere 110. A light source inspection apparatus 101 is known which includes an incident port 111 and an exit port 121 for emitting the light beam in the integrating sphere toward the outside. In this light source inspection apparatus 101, an attachment portion 113 for attaching the light emitting diode 190 to be inspected is attached to the incident port 111, and a light receiving portion 123 is attached to the emission port 121. The entrance port 111 and the exit port 121 are disposed at positions where directions from the center to the center of the cavity in the inner peripheral surface of the integrating sphere 110 are orthogonal to each other. It is located at a latitude of 0 °).

  In the integrating sphere 110, a baffle 130 is disposed between the light emitting diode 190 and the light receiving unit 123 (at a position of 45 ° latitude) so that the light from the light emitting diode 190 does not directly enter the light receiving unit 123. Is provided.

JP 2008-76126 A

  However, the present inventor has found that, when a total luminous flux test is performed using the light source inspection apparatus 101, even if the same light-emitting diode 190 is an inspection target, the photometric results are different each time the inspection is performed. As a result of intensive studies by the present inventor on this point, when there is a difference in the angle or height at which the light emitting diode 190 is attached to the attachment portion 113 (the position of the tip portion of the light emitting diode 190), the above photometric result is obtained. It turned out that there was a difference. When this inventor further examines this relationship, it is considered that a difference in the photometric result is caused for the following reason.

  First, the integrating sphere 110 is theoretically proportional to the intensity of the emitted light of the light emitting diode 190 itself without depending on the traveling direction of the light, etc., because the emitted light of the light emitting diode 190 is diffusely reflected many times. Although a light beam having a uniform intensity distribution can be obtained, in reality, the light beam is slightly absorbed for each reflection on the inner peripheral surface of the integrating sphere 110, and therefore, the region where the light beam emitted from the light emitting diode 190 first enters. The light beam reflected by (surface) is stronger than the light beam reflected by other regions. In addition, the photometric value in the light receiving unit 123 is easily affected by the light beam reflected by the location facing the light receiving unit 123 (exit port 121) on the inner circumferential surface of the integrating sphere 110, that is, when the reflected beam at the facing location is strong. The photometric value of the light receiving unit 123 is a high value. For this reason, when inspecting the light emitting diode 190 having high directivity of the emitted light, the light emitting diode 190 is attached to the attachment portion 113 so that the portion of the light emitting diode 190 where the intensity of the emitted light is directly opposite the light receiving portion 123. When incident on a spot (for example, when a light beam within the half-value angle of the light emitted from the light-emitting diode 190 is incident on the opposite spot), the intensity of the light beam reflected at the opposite spot increases. Is a relatively high value. On the other hand, when the light beam emitted from the light emitting diode 190 is not directly incident on the facing portion, only the reflected light beam from the other inner peripheral surface is incident on the facing portion of the light receiving portion 123, and the intensity of the light beam reflected at the facing portion is high. Accordingly, the photometric value of the light receiving portion 123 becomes a relatively low value. Thus, it is considered that the photometric result of the light receiving portion 123 varies depending on the mounting angle of the light emitting diode 190 in the mounting portion 113.

  The present invention has been made in view of these points, and an object of the present invention is to provide a light source inspection apparatus that can easily and accurately measure the optical performance of a light source using an integrating sphere.

The light source inspection apparatus of the present invention made to solve the above problems is
An integrating sphere having an inner peripheral surface that reflects light rays;
An incident port for allowing the light beam to be inspected to enter the integrating sphere,
An exit port for emitting the rays in the integrating sphere toward the outside, and a photometric means for measuring the rays in the integrating sphere from the exit port;
The photometric means controls the photometric path in the integrating sphere within a certain range,
A baffle is further provided between the incident port and the photometric region that intersects the photometric path on the inner circumferential surface of the integrating sphere.

  In this inspection apparatus, the light beam emitted from the light source incident from the incident port is repeatedly reflected on the inner peripheral surface of the integrating sphere, and the reflected light beam in the light measurement region among the reflected light beam is measured. The means can perform photometry, and the light source can be inspected based on the photometry results. In the inspection apparatus, since the baffle is disposed between the light measurement region and the incident port, the baffle can prevent the emitted light from the light source from directly entering the light measurement region. That is, the light beam incident on the light measurement region can be a light beam reflected on the inner peripheral surface other than the light measurement region. In other words, even if the light source is mounted with an inclination and the measured region is located within the half-value angle of the light beam emitted from the light source, the light beam emitted from the light source is blocked by the baffle blocking the light beam emitted from the light source. Can be prevented from directly entering the measured region. For this reason, the difference of the photometry result by the attachment state of a light source can be decreased, and the optical performance of a light source can be measured easily and correctly.

  In particular, in the inspection apparatus, the photometric means controls the photometric path as described above, and is provided so as to measure the reflected light of the photometric area that is a certain range of the inner circumferential surface of the integrating sphere. As described above, it is easy to install a baffle that prevents the light emitted from the light source from being directly incident, whereby the optical performance of the light source can be measured easily and accurately. That is, for example, when the photometric means measures all the light beams reaching the exit port (when the entire inner sphere of the integrating sphere is set as the photometric area), a baffle is provided between the photometric area and the exit port. Is extremely difficult, and photometry with accurate optical performance becomes difficult. On the other hand, in the inspection apparatus, the photometric means measures the reflected light of the photometric area in a certain range on the inner peripheral surface of the integrating sphere, so that the baffle can be easily placed between the photometric area and the exit port. The optical performance of the light source can be measured easily and accurately.

  The inspection apparatus preferably employs a configuration in which the baffle is disposed outside the photometry path. Thereby, the photometry means can prevent photometry of the reflected light from a baffle, and can perform a test | inspection with sufficient precision. That is, when a baffle is provided in the photometric path, the photometric means also measures the reflected light of the baffle, and the reflected light of the baffle lacks uniformity with the reflected light on the inner peripheral surface of the integrating sphere. This is because the inspection accuracy is likely to be inferior due to the strong tendency.

  In the inspection apparatus, it is possible to adopt a configuration in which the baffle is disposed at a position closer to the light measurement region than the emission port, but closer to the emission port than the light measurement region. It is preferable to employ a configuration in which a baffle is disposed at a position. This has the advantage that the baffle can be easily arranged outside the photometric path of the photometric means.

  Furthermore, in the said inspection apparatus, it is preferable that the baffle is formed in flat form. It is possible to adopt a configuration in which the flat baffle is disposed substantially parallel to a virtual straight line connecting the emission port and the center of the cavity in the inner peripheral surface of the integrating sphere. With such a configuration, even if the light beam emitted from the light source enters the baffle, the light beam is easily reflected by the baffle in the direction toward the center of the integrating sphere. As a result, the light rays incident on the baffle are also reflected on the inner peripheral surface of the integrating sphere, and by this reflection, the light rays are incident on the light measurement region, so that all the light rays including the light rays incident on the baffle are measured. Photometry can be performed.

  It is also possible to employ a configuration in which a flat baffle projects from the inner peripheral surface of the integrating sphere toward the center of the cavity in the inner peripheral surface of the integrating sphere. With such a configuration, light rays that repeatedly reflect inside the integrating sphere tend to have uniform intensity regardless of location and angle. In other words, since the baffle is arranged along the radial direction of the integrating sphere, the presence of the baffle in the integrating sphere hardly affects the isotropic dispersion of the light, and the light beam that repeatedly reflects inside the integrating sphere The strength tends to be uniform regardless of the location and angle.

  Furthermore, in the said inspection apparatus, it is preferable to employ | adopt the structure which a baffle has a reflective layer containing a white pigment on the surface at least. Thereby, the light beam incident on the baffle can be accurately reflected by the reflection layer, and the photometry can be performed on all the light beams including the light beam incident on the baffle.

  Moreover, it is preferable that the said inspection apparatus is further equipped with the attaching part to which the light source which is inspection object is attached so that attachment or detachment is possible. Accordingly, the light source can be inspected by attaching the light source to the attachment part detached from the emission port, attaching the attachment part to which the light source is attached to the emission port, and then causing the light source to emit light. In addition, after the inspection is completed, the attachment portion can be detached from the emission port, the light source can be detached from the attachment portion, and a new light source can be attached to the attachment portion as described above.

  As described above, in the light source inspection apparatus of the present invention, the light metering means controls the light metering path, and prevents the light beam emitted from the light source from directly entering the light metered area by the baffle, thereby mounting the light source. The difference in the photometric results due to can be reduced, and the optical performance of the light source can be measured easily and accurately.

It is a schematic block diagram of the inspection apparatus of the light source which concerns on one Embodiment of this invention. It is explanatory drawing of the integrating sphere of the inspection apparatus of FIG. 1, and is a schematic front view containing a partial cross section. It is explanatory drawing of the integrating sphere of the inspection apparatus of the light source which concerns on other embodiment of this invention, and is a schematic front view including a partial cross section. It is explanatory drawing of the integrating sphere of the inspection apparatus of the light source of a prior art example, and is a schematic front view including a partial cross section.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as appropriate.

[First embodiment]
The light source inspection apparatus 1 shown in FIG. 1 has an integrating sphere 10 having an inner peripheral surface that reflects light rays, and an incident port 11 for allowing the light emitted from a light emitting die auto 90 (light source) to be inspected to enter the integrating sphere 10. An exit port 21 for emitting the light rays in the integrating sphere 10 to the outside, a baffle 30 disposed in the integrating sphere 10, and a photometric means 50 for measuring the light rays in the integrating sphere 10. And control means 70 for controlling various members.

<Integrating sphere 10>
The integrating sphere 10 has a substantially spherical inner peripheral surface 10a, and the inner side of the inner peripheral surface 10a is formed in a substantially spherical cavity. The inner peripheral surface 10a is provided to reflect light rays, and the inner light rays are made uniform by repeatedly reflecting the light rays on the inner peripheral surface 10a. Various sizes of cavities inside the integrating sphere 10 (the diameter of the sphere composed of the inner peripheral surface 10a) can be adopted depending on the inspection object. For example, an integrating sphere having a spherical cavity with a diameter of 330 mm is used. Can be used.

  The inner peripheral surface 10a of the integrating sphere 10 is formed in white so as to diffusely reflect light rays, and is specifically made of a resin containing a white pigment. Here, as the white pigment, for example, titanium oxide (titanium white) can be used. In addition, as the white pigment, silica, calcium carbonate (chalk), zinc oxide (zinc white), lead carbonate (lead white), barium sulfate, and the like can also be used. The resin containing the white pigment constitutes a layered inner peripheral surface 10a by being coated on a substantially spherical surface. In addition to the coating method, the design of the member including the inner peripheral surface 10a itself from a synthetic resin containing a white pigment can be appropriately changed. In addition to making the inner peripheral surface 10a white, the design of the inner peripheral surface 10a such as silver or gold can be appropriately changed depending on the wavelength to be measured.

<Incoming port 11 and outgoing port 21>
Two through holes 11 and 21 are formed in the inner peripheral surface 10 a of the integrating sphere 10. One of the through holes 11 functions as an incident port for allowing a light beam to enter inside, and the other through hole 21. Functions as an emission port for emitting light to the outside.

  A mounting portion 13 to be described later is attached to the incident port 11, and the photometric means 50 is attached to the outgoing port 21.

  Furthermore, the exit port 21 and the entrance port 11 are arranged at positions where directions from the respective centers to the center O of the cavity of the integrating sphere 10 are orthogonal (for example, the entrance port 11 is at a position of 0 ° latitude). In this case, the emission port 21 is arranged at a latitude of 90 °). A direction (radial direction) from the center of the incident port 11 (mounting portion 13) toward the center O of the integrating sphere 10 and a direction (radial direction) from the center of the exit port 21 toward the center O of the integrating sphere 10 Is preferably 70 ° to 110 °, more preferably 80 ° to 100 °, and particularly preferably 85 ° to 95 °. If it is less than the above lower limit value, the light beam emitted from the light emitting diode 90 is likely to be incident on the photometric region S described later, so that the arrangement of the baffle 30 becomes difficult. This is because the arrangement of the baffle 30 becomes difficult due to the proximity of 90.

<Mounting part 13>
The attachment portion 13 is a member that is detachably attached to the emission port 11 and to which the light emitting diode 90 to be inspected is detachably attached.

  The attachment portion 13 includes a pedestal 15 to which the light emitting diode 90 is detachably attached, and a cover body 17 that is attached to the pedestal 15 and detachably attached to the emission port 21. That is, for example, by removing the cover body 17 from the emission port 21, attaching the light emitting diode 90 to be inspected to the base 15 attached to the cover body 17, and then attaching the cover body 17 to the emission port 21. The light emitting diode 90 can be arranged at the inspection position. The pedestal 15 is configured such that the light emitting diode 90 is attached to the surface (the surface on the center O side of the integrating sphere 10 when mounted) in a protruding state. The surface of the pedestal 15 is an extension of the inner peripheral surface 10 a of the integrating sphere 10. It is approximately located on the curved surface. For this reason, the light emitting diode 90 is attached to the attachment portion 13 such that the tip of the light emitting diode 90 to be inspected is located on the inner side (center O side) of the inner peripheral surface 10a of the integrating sphere 10. In addition, it is preferable that the base 15 and the cover body 17 are comprised from resin in which at least the surface (surface exposed inside the integrating sphere 10) contains a white pigment.

<Photometric means 50>
The photometric means 50 is a means for measuring light rays in the integrating sphere 10 while controlling the photometric path P in the integrating sphere 10 within a certain range. As shown in FIG. 1, the photometric means 50 includes a condensing optical unit 51 through which light rays from the exit port 21 of the integrating sphere 10 pass, and a spectroscope 53 that measures the light rays that have passed through the condensing optical unit 51. It has.

  The condensing optical unit 51 of the photometry means 50 includes a pinhole and a plurality of condensing elements. Here, the condensing element is comprised from the mirror. The condensing optical unit 51 controls the photometric path P in the integrating sphere 10. Specifically, the photometric path P in the integrating sphere 10 is controlled to have a substantially conical shape having a vertex (focal point) in the vicinity of the emission port 21. Of the inner circumferential surface 10 a of the integrating sphere 10, a region intersecting with the photometric path P is a photometric region S, and only reflected light reflected by the measured light region S of the inner circumferential surface 10 a of the integrating sphere 10 is measured. The means 50 is configured to measure light. Of the reflected light rays reflected by the photometric region S, the reflected light rays that are reflected outward from the photometric path P are not measured by the photometric means 50, and the reflected light rays that are reflected in the inner direction of the photometric path P are applied to the photometric means 50. Metered.

  The photometric path P controlled by the condensing optical unit 51 of the present embodiment is controlled such that the photometric axis (the conical rotation axis) passes through the center O of the integrating sphere 10. Further, the photometry path P is controlled by the condensing optical unit 51 so that the photometric area S is in a certain range. Here, in the photometric area S, it is preferable that an angle α formed by a virtual straight line connecting one end of the photometric area S and the center O of the integrating sphere 10 with respect to the photometric axis is 60 ° or less. In particular, the angle α is preferably 10 ° or more and 45 ° or less, more preferably 15 ° or more and 35 ° or less, and particularly preferably 20 ° or more and 30 ° or less. If the angle α is less than the lower limit value, the photometric area S becomes narrow. Therefore, if the photometric area S is partially or temporarily soiled (for example, dust adheres), the photometric error is large. As a result, the photometric accuracy may be reduced. On the other hand, if the angle α exceeds the upper limit, it may be difficult to dispose a baffle 30 described later outside the photometric path P. The condensing optical unit 51 controls the photometry path P so that the mounting portion 13 (and the light emitting diode 90 attached thereto) is not located in the photometry path P. Thus, the light emitted from the light emitting diode 90 is not directly measured by the photometric means 50.

  The area of the photometric region S is preferably 25% or less with respect to the entire area of the inner circumferential surface 10a of the integrating sphere 10. In particular, this ratio is preferably 1% or more and 15% or less, more preferably 2% or more and 10% or less, and particularly preferably 3% or more and 7% or less. If it is less than the lower limit, the photometric area S becomes narrow and the amount of light to be measured may be insufficient, and if the upper limit is exceeded, it will be difficult to dispose a baffle 30 described later outside the photometry path P. This is because there is a fear.

  The spectroscope 53 is provided so that the intensity for each wavelength of the light beam transmitted through the condensing optical unit 51 can be measured. As the spectroscope 53, a conventionally known one can be used. A spectroscope having a diffraction grating or a prism and using the diffraction grating or the prism to split the light beam for each wavelength is preferably used. The spectroscope 53 has a photomultiplier tube (PMT) that senses the intensity of the light beam dispersed as described above. Further, the spectroscope 53 is connected to the control unit 70 and is configured to rotate a prism in accordance with an instruction from the control unit 70 to supply a light beam having a desired wavelength to the photomultiplier tube.

  The spectroscope is connected to a photon counter 57 that measures an electric signal amplified and converted by a photomultiplier tube. The photon counter is connected to the control means 70 and supplies measured data to the control means 70.

<Baffle 30>
The baffle 30 is disposed inside the integrating sphere 10 between the photometric region S and the attachment portion 13 and outside the photometry path P. The light source inspection apparatus 1 emits light from the attachment portion 13 by the baffle 30. The light beam emitted from the diode 90 is provided so as not to directly enter the photometric region S. Specifically, the baffle 30 is attached to the inner peripheral surface 10 a of the integrating sphere 10, and protrudes from the inner peripheral surface 10 a toward the center O side of the integrating sphere 10. The baffle 30 is disposed on the opposite side of the emission port 21 (the measured region S side) from the attachment portion 13 and on the attachment portion 13 (the center of the emission port 21) side of the measured region S (the center). ing.

  The baffle 30 is made of a white plate material, and the baffle 30 is made of a resin containing a white pigment. Here, as the white pigment, it is preferable to use the same pigment as the pigment used for the inner peripheral surface 10a of the integrating sphere 10. Specifically, titanium oxide (titanium white) can be used as the white pigment. In addition, as the white pigment, silica, calcium carbonate (chalk), zinc oxide (zinc white), lead carbonate (lead white), barium sulfate, and the like can also be used. Here, the baffle 30 can be formed from a molded product of a resin containing this white pigment. For example, a baffle 30 in which the resin is coated on the outer surface of a plate material can also be used. Note that the baffle 30 can also be configured from a plate material having an outer surface such as silver or gold according to the wavelength to be measured.

  Further, the baffle 30 protrudes substantially parallel to a virtual straight line connecting the incident port 11 (the center thereof) and the center O of the integrating sphere 10. Here, “substantially parallel” is a concept including a case where the baffle 30 is inclined by about 5 ° with respect to a virtual straight line. In addition, it is preferable that the baffle 30 is provided so as to be inclined in a direction parallel to the virtual straight line or away from the virtual straight line toward the center O side of the integrating sphere 10. As a result, the light beam incident on the baffle 30 from the light emitting diode 90 and reflected by the baffle 30 is easily directed in the direction of the center O of the integrating sphere 10, and photometry is performed on all light beams including the light beam incident on the baffle 30. And accurate and accurate inspection can be performed. That is, if the light beam reflected by the baffle 30 is reflected (recursed) toward the light emitting diode 90 and the mounting portion 13 side, the light beam may be absorbed by the light emitting diode 90 or the like. By adopting such a configuration, an accurate and accurate inspection can be performed on the entire light beam emitted from the light emitting diode 90.

  Further, the baffle 30 protrudes so that the protruding edge 30 a does not reach the photometric path P, and the baffle 30 is disposed outside the photometric path P. Further, the baffle 30 is provided such that a virtual straight line connecting the protruding end edge 30a and the attachment portion 13 is located outside the photometric area S with respect to the inner peripheral surface 10a. Here, the distance D between the maximum protruding position of the baffle 30 (the position of the protruding end edge 30a closest to the center of the integrating sphere 10) and the center O of the integrating sphere 10 is 30% of the radius of the integrating sphere 10. It is preferably 80% or less, more preferably 35% or more and 70% or less, and particularly preferably 40% or more and 60% or less. If it is less than the above lower limit value, the baffle 30 is too small, so that it may not be possible to accurately prevent the light emitted from the light emitting diode 90 from directly entering the measured region S due to the size of the light emitting diode 90 or the like. Because. Further, if the upper limit is exceeded, the baffle 30 is too large, which may hinder the uniformization of the light rays inside the integrating sphere 10.

  Also, assuming that the center of the incident port 11 is at a position of 0 ° latitude and the center of the exit port 21 is at a position of 90 ° latitude, the baffle 30 has the same latitude as the center of the entrance port 11 and the center of the exit port 21. And it protrudes from the internal peripheral surface 10a of the position of latitude-10 degrees. Here, when the center of the entrance port 11 is 0 ° latitude and the center of the exit port 21 is located near 90 ° latitude, the attachment position of the baffle 30 is preferably -40 ° to −5 ° latitude. -30 ° to -7 ° is more preferable, and -20 ° to -9 ° is more preferable. If it is less than the above lower limit value, the baffle 30 is too close to the photometric region S, so that the light beam emitted from the light emitting diode 90 is prevented from directly entering the photometric region S and is baffled outside the photometric path P. It becomes difficult to arrange 30. Further, when the upper limit is exceeded, the baffle 30 is too close to the light emitting diode 90, so that a light beam having a high intensity of light emitted from the light emitting diode 90 is incident on the baffle 30 and may affect the evaluation of optical performance. This is because of this.

<Control means 70>
The control means 70 adjusts the output of the light emitting diode 90 (power supplied to the light emitting diode 90), gives an instruction to the light emitting diode control section 73, and receives photometric data from the photometric means 50. The control part main body 71 to receive is provided.

  The control unit main body 71 receives data from the photo counter 57, calculates the intensity at each wavelength of the light emitting diode 90 based on these data, and outputs the intensity and the output signal to the light emitting diode control unit 73 and the like. And a program for judging the optical performance of the light emitting diode 90 based on the above. In addition, this control part main body 71 can be comprised from a normal computer system, for example.

<Inspection method>
The light source inspection apparatus 1 of the present embodiment has the above-described configuration. Next, an inspection method using the inspection apparatus 1 will be described.

  First, in the inspection, the attaching portion 13 is detached from the exit port 21 of the integrating sphere 10, the light emitting diode 90 to be inspected is attached to the attaching portion 13, and then the attaching portion 13 is attached to the exit port 21 of the integrating sphere 10.

  Then, the control means 70 controls the output of the light emitting diode 90 to cause the light emitting diode 90 to emit light. The outgoing light from the light emitting diode 90 is repeatedly reflected in the integrating sphere 10 and reaches the outgoing port 21 as a uniform light. Of the light rays reaching the exit port 21, the light rays in the photometric path P controlled by the condensing optical unit 51 are transmitted to the spectroscope 53. The transmitted light beam is measured by the spectroscope 53 and the photo counting unit. Based on the measured data, the control means 70 determines whether or not a desired light beam is emitted from the light emitting diode 90 (whether or not the light emitting diode 90 has a desired light emission characteristic). become.

<Advantages>
According to the light source inspection apparatus 1 of the present embodiment, the baffle 30 is disposed between the light measurement region S facing the emission port 21 and the mounting portion 13 as described above, and the baffle 30 is separated from the light emitting diode 90. Since the outgoing light beam is prevented from directly entering the photometric region S, the difference in the photometric results can be reduced even if the light emitting diode 90 is attached to be inclined to the mounting portion 13 side. The optical performance of the light emitting diode 90 can be measured easily and accurately.

  Further, since the baffle 30 is disposed outside the photometric path P of the photometric means 50, the reflected light from the inner peripheral surface 10a (photometric area S) of the integrating sphere 10 other than the reflected light from the baffle 30 is measured. 50 can perform photometry, and the test result can be easily and reliably determined based on the photometry result. That is, when the baffle 30 is present in the photometry path P, the photometry means 50 also measures the reflected light from the baffle 30, and the reflected light from the baffle 30 is reflected on the inner peripheral surface 10 a of the integrating sphere 10. Therefore, when the baffle 30 is located in the photometric path P, it is necessary to make a determination in consideration of the reflected light from the baffle 30, and the determination method is difficult. It is because it becomes.

  Further, in the inspection apparatus 1, the baffle 30 is disposed at a position closer to the mounting portion 13 than the photometric region S, and therefore the baffle 30 is disposed outside the photometric path P of the photometric means 50. easy.

  Further, the photometry path P is limited by the condensing optical unit 51, and the photometry means 50 is provided so that the reflected light of the photometric area S within a certain range of the inner peripheral surface 10a of the integrating sphere 10 is measured. It is easy to install the baffle 30 outside P, and thereby the optical performance of the light emitting diode 90 can be measured easily and accurately.

  Further, since the baffle 30 is white, the light incident on the baffle 30 can be accurately reflected, and photometry can be performed on all light including the light incident on the baffle 30 as a photometric object. In particular, since the baffle 30 has a plate shape, the uniformity of the reflected light beam can be increased, and the function of the integrating sphere 10 is hardly hindered.

  Further, since the baffle 30 has the same kind of white pigment as the white pigment on the inner peripheral surface 10a of the integrating sphere 10, it is easy to obtain the same uniformity as the reflection of the inner peripheral surface 10a of the integrating sphere 10 and the presence of the baffle 30. It is difficult for photometric errors due to.

[Other Embodiments]
In the above-described embodiment, the above-described configuration has the above-described advantages. However, the present invention is not limited to this, and the design can be changed as appropriate within the intended scope of the present invention.

  That is, in the above-described embodiment, the baffle 30 is provided so as to protrude substantially parallel to the virtual straight line connecting the incident port 11 and the center O of the integrating sphere 10, but the present invention is not limited to this. For example, as shown in FIG. 3, the flat baffle 30 is not substantially parallel to the virtual straight line but protrudes from the inner circumferential surface 10 a of the integrating sphere 10 toward the center O of the integrating sphere 10. It is also possible to adopt. As shown in FIG. 3, the baffle 30 is disposed along the radial direction of the integrating sphere 10 so that the presence of the baffle 30 in the integrating sphere 10 hardly affects the isotropic dispersion of the light beam. 10 has an advantage that the light beam that repeats reflection within 10 tends to have uniform intensity regardless of location and angle.

  In addition, in FIG. 3, the same code | symbol is used about the member which has the structure or function similar to 1st embodiment. Further, the baffle 30 has the same latitude as the center of the entrance port 11 and the center of the exit port 21 when the center of the entrance port 11 is at a position of 0 ° latitude and the center of the exit port 21 is at a position of 90 ° latitude. And it protrudes from the internal peripheral surface 10a of the position of latitude -45 degrees. Here, when the center of the entrance port 11 is 0 ° latitude and the center of the exit port 21 is located in the vicinity of 90 ° latitude, the attachment position of the baffle 30 is preferably -60 ° to −15 ° latitude. The angle is more preferably −55 ° to −25 °, and further preferably −50 ° to −35 °. If it is less than the above lower limit value, the baffle 30 is too close to the photometric region S, so that the light beam emitted from the light emitting diode 90 is prevented from directly entering the photometric region S and is baffled outside the photometric path P. It becomes difficult to arrange 30. When the above upper limit is exceeded, the baffle 30 is too close to the light emitting diode 90 and a light beam having a high intensity of light emitted from the light emitting diode 90 is incident on the baffle 30, and the incident light beam is reflected and reflected by the light emitting diode 90. This is because there is a possibility that the evaluation of the optical performance is affected. Note that the protruding end edge 30a of the baffle 30 of FIG. 3 is also preferably provided at the same position (distance from the center O) as the protruding end edge 30a (see FIG. 2 and the like) of the first embodiment.

  Moreover, in the said embodiment, although the baffle 30 demonstrated what comprised the white plate-shaped object, this invention is not limited to this. That is, since the baffle is plate-shaped, it is difficult to inhibit isotropic dispersion of light rays due to the presence of the baffle, but baffles having other shapes can be employed. Although it is not limited that the baffle is composed of a white member, the surface of the baffle is preferably a white reflective layer. For example, the baffle 30 is composed of a member coated with a paint containing a white pigment on the surface. It is also possible.

  Furthermore, in the above embodiment, a light emitting diode (light emitting element) has been described as an example of a light source to be inspected. However, in the light source inspection apparatus of the present invention, other light emitting elements, and further, a radar beam irradiation member is provided. It is also possible to make it an inspection object. In the above-described embodiment, the light source mounting portion is described as being attached to the output port. For example, the light source to be inspected is disposed outside the integrating sphere, and the light emitted from the light source is guided. It is also possible to configure such that it is incident from the exit port.

  Further, the integrating sphere of the above-described embodiment may be further provided with a standard data light source incident port, and a light beam for collecting standard data may be incident from the standard data light source incident port. Thereby, the performance evaluation of the integrating sphere itself can be performed using the light source for collecting the standard data. For this reason, for example, in the control means based on the result of performance evaluation of the integrating sphere itself using the light source for collecting the standard data according to the change in the reflectance of the inner peripheral surface due to long-term use of the integrating sphere. Measurement data can be corrected, and relatively accurate evaluation of optical performance can be continued even if the integrating sphere is used for a long period of time.

  Further, in the above-described embodiment, the spectroscope 53 has a photomultiplier tube. However, the present invention is not limited to this, and a two-dimensional light receiving device such as a charge coupled device detector (CCD), for example. It is also possible to employ one having a vessel. In this case, it is preferable that the two-dimensional light receiver is connected to the control unit as in the above embodiment, and the measured data is supplied to the control unit 70.

  Moreover, in the said embodiment, although the photometry means 50 demonstrated what has a mirror, this invention is not limited to this, For example, what has a lens as a condensing element is employable. Furthermore, it is also an item that can be appropriately changed in design by making the condensing element movable so that the photometric area can be changed.

[Experimental example]
Using the light source inspection apparatus according to the first embodiment and the conventional inspection apparatus, an experiment was performed on the difference in detection accuracy depending on the mounting angle of the light emitting diode.

  In this experiment, a φ5 bullet type light emitting diode (trade name “E1L51-3B (manufactured by Toyoda Gosei))” was used as the light emitting diode. Further, when the light emitting diode is normally attached to the attachment portion (at an inclination angle of 0 ° with respect to the integrating sphere center), the tip of the light emitting diode protrudes to the center side by about 14 mm from the inner peripheral surface of the integrating sphere. A light emitting diode was attached.

(Experimental example 1)
With respect to the light emitting diode in a normally mounted state, the total luminous flux was measured after 100 seconds had elapsed after the light emitting diode was turned on. This measurement was performed 10 times for the same light emitting diode.

(Experimental Examples 2-5)
Next, as Experimental Example 2, the light-emitting diode was inclined 45 ° toward the emission port side, and the same measurement as in Experimental Example 1 was performed. Similarly, as Experimental Example 4, the same measurement as in Experimental Example 1 was performed by inclining the light-emitting diode by 45 ° toward the measured region. Similarly, as Experimental Examples 3 and 5, the light-emitting diode was inclined between the emission port and the measured region (right side and left side), respectively, and the same photometry as in Experimental Example 1 was performed.

(Photometric result)
The photometric results of Experimental Examples 1 to 5 are shown in Table 1.

In the table, the average (mW) is an average of 10 photometric values, the highest (mW) is the highest value of 10 photometric values, and the minimum (mW) means a minimum value of 10 times.
The maximum error (Δ%) is a numerical value according to the following formula.
Maximum error = (maximum value-minimum value) x 100 / (2 x average)
Furthermore, the relative intensity (%) is a ratio of the average photometric value of each experimental example to the average photometric value of Experimental example 1, and the intensity difference (%) means a difference between 100% and the relative intensity.

(Evaluation)
As is clear from the results in Table 1, according to the light source inspection apparatus, it was found that the difference in photometric values was small in Experimental Examples 1 to 5. That is, as is apparent from Experimental Examples 1 to 5, even if the mounting angle of the light emitting diode is changed, the photometric value is unlikely to change. For this reason, according to the said light source inspection apparatus, it is hard to be influenced by the attachment angle etc. of a light emitting diode, and photometry of exact optical performance is possible.

(Experimental Examples 6 to 11 and photometric results thereof)
Experimental Examples 6 to 11 were subjected to the same tests as Experimental Examples 1 to 5 with different inspection objects and attachment angles. Table 2 shows the measurement results of Experimental Examples 6 to 11. About these experimental examples 6-11, brand name E1L51-AW0C * -01 (made by Toyoda Gosei Co., Ltd.) was used as a light emitting diode which is a test object. Moreover, about Experimental Examples 7-11, unlike Experimental Examples 2-5, the attachment angle (tilt angle) was 30 degrees.

  As is clear from the results in Table 2, it was found that according to the light source inspection apparatus, the difference in the photometric values in Experimental Examples 6 to 11 was small. That is, as apparent from Experimental Examples 6 to 10, even if the mounting angle of the light emitting diode is changed, the photometric value hardly changes, and as is clear from Experimental Examples 6 and 11, the mounting height of the light emitting diode is shifted. Even if this occurs, it is difficult for the photometric value to vary. For this reason, according to the said light source inspection apparatus, it is hard to be influenced by the attachment angle etc. of a light emitting diode, and photometry of exact optical performance is possible.

  As described above, the light source inspection apparatus of the present invention can easily and accurately measure the optical performance of the light source using an integrating sphere, and can be suitably used for, for example, a total luminous flux test of a light emitting diode.

DESCRIPTION OF SYMBOLS 1 Inspection apparatus 10 Integrating sphere 10a Inner peripheral surface 11 Incident port 13 Mounting part 15 Base 17 Cover body 21 Outlet port 30 Baffle 50 Photometric means 51 Condensing optical unit 53 Spectrometer 57 Photon counter 70 Control means 71 Control part main body 73 Light emitting diode Control unit 90 Light-emitting diode O Center P Photometric path S Photometric area α Angle D Distance

Claims (3)

An integrating sphere having an inner peripheral surface that reflects light rays;
An incident port for allowing the light beam to be inspected to enter the integrating sphere,
An exit port for emitting the rays in the integrating sphere toward the outside, and a photometric means for measuring the rays in the integrating sphere from the exit port;
The photometric means controls the photometric path in the integrating sphere within a certain range,
Further example Bei a baffle disposed between the target metering area and the entrance port intersects the metering path of the inner peripheral surface of the integrating sphere,
The baffle is disposed outside the photometric path and at a position closer to the incident port than the photometric region;
The baffle is formed in a flat plate shape, and is arranged substantially parallel to a virtual straight line connecting the incident port and the center of the cavity in the inner peripheral surface of the integrating sphere,
A light source inspection apparatus in which the distance between the maximum protruding position of the baffle and the center of the integrating sphere is 30% to 80% with respect to the radius of the integrating sphere . The light source inspection device according to claim 1, wherein the baffle has a reflective layer containing a white pigment on at least a surface thereof. The light source inspection apparatus according to claim 1 , further comprising an attachment portion that is detachably attached to the incident port and to which a light source to be inspected is detachably attached.

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