JP6432262B2 - Luminous flux measuring apparatus and luminous flux measuring method - Google Patents

Description

  The present invention relates to a light beam measuring apparatus and a light beam measuring method for measuring a light beam emitted from an object for light beam measurement.

  Conventionally, the total luminous flux (lm: lumen) has been used as an index for evaluating the performance of a light source used in a lighting fixture or the like. As a device for measuring the total luminous flux with higher accuracy, a spherical luminous meter using an integrating sphere is known. In this spherical light meter, a light source that is lit is placed in an integrating sphere, and a light beam from the light source is repeatedly reflected by a diffuse reflection material (for example, barium sulfate or PTFE (polytetrafluoroethylene)) applied to the inner wall of the integrating sphere. Due to this repeated reflection, the illuminance on the inner wall surface of the integrating sphere is made uniform. Using the fact that the illuminance of the inner wall of the integrating sphere is proportional to the total luminous flux of the light source, the illuminance of the inner wall of the integrating sphere is measured, and this measured value is measured with the previously acquired standard light source. To obtain the total luminous flux from the light source to be measured.

  As a light flux measuring device using an integrating sphere, for example, Patent Literature 1 discloses a light radiation pattern measuring device. As shown in FIG. 8, the light radiation pattern measuring apparatus 800 includes a plurality of light receiving portions 830a to 830e disposed so as to surround the measurement target WK at different radiation angles θ, and light incident on each light receiving portion. Are respectively included in the detector 840.

  On the other hand, the spherical zone coefficient method is known as a method for obtaining total luminous flux from light distribution measurement data without using an integrating sphere (Non-patent Documents 1 and 2). In a light source having an axially symmetric light distribution, the front light flux can be obtained by the spherical zone coefficient method by measuring the light distribution of several cross sections (Non-patent Document 3). The light distribution is a spatial distribution (angle distribution) of luminous intensity emitted from the light source, and the luminous intensity is a light beam included in a minute solid angle. Therefore, the total luminous flux is obtained by integrating the luminous intensity with respect to all solid angles (all spaces). In a light source having an axially symmetric light distribution, if a light distribution in a plane including the symmetric axis is obtained, the area of the spherical zone shown in FIG. 9 is obtained, and the total luminous flux is obtained by integrating those spherical zones. It is done. The integration of this solid angle is shown in FIG. As the surface area of the sphere centered on the light source, the area obtained by dividing it into strips in a cross section perpendicular to the symmetry axis is the spherical zone coefficient in the inclination angle θ direction from the vertical direction, and the luminous intensity in the θ direction of the light source The product is a light beam that passes through a solid angle stretched on a light source represented by a spherical zone. Therefore, the total luminous flux is obtained by adding the ball bands to form a sphere having all solid angles. That is, the spherical zone coefficient method is a method of performing quadrature quadrature for the surface area of a sphere.

  The spherical zone coefficient is a value unrelated to the luminous intensity, and can be calculated in advance. FIG. 11A shows a spherical zone coefficient in which θ is set every 10 °, and FIG. 11B shows θ set every 5 °. Since the actual light source is not completely symmetric with respect to the vertical axis, the light distribution measurement is performed on a plurality of vertical cross sections such as horizontal angles 0 °, 90 °, 180 °, 270 °, etc. On the other hand, the total luminous flux is obtained by the spherical zone coefficient method, and these are averaged to obtain the total luminous flux of the light source.

JP 2005-172665 A Japanese Patent No. 49332045

The Illuminating Society of Japan "Light Measurement Manual", p. 208 (1990) JIS C 8105-5: 2014 Lighting equipment-Part 5: Light distribution measurement method Kazuaki Okubo “Fundamentals and Applications of Light Measurement of Light Sources and Displays 3—Light Distribution Measurement of Light-Emitting Devices—” Liquid Crystal, Vol. 15, No. 1, p. 44 (2011)

  However, in the spherical zone coefficient method, as shown in FIG. 12, it is necessary to repeatedly measure the luminous intensity from the light source at each position while changing θ, and to multiply the obtained luminous intensity by a predetermined spherical zone coefficient. There was a problem of becoming complicated. On the other hand, in recent years, illumination such as light emitting diodes (LEDs) has become widespread, and there is an increasing demand for quickly measuring all the luminous fluxes, and a simple luminous flux measurement method has been demanded.

  The present invention has been made to solve such conventional problems. An object of the present invention is to provide a light flux measuring apparatus and a light flux measuring method capable of quickly measuring a light flux without using an integrating sphere.

Means for Solving the Problems and Effects of the Invention

  In order to achieve the above object, according to a light beam measuring apparatus according to one aspect of the present invention, a light beam measuring apparatus for measuring a light beam from an object to be measured based on the spherical zone coefficient method, A jig for holding an object on a holding plane, and a hemispherical surface formed into a hemispherical shape are formed on the joint surface with the jig, and the hemispherical surface is formed. A main body for placing the measurement object held on the holding plane of the jig at the center of the sphere, and a hemispheric surface of the main body, the center of the sphere formed by the hemisphere A plurality of apertures that are opened at positions that form a predetermined inclination angle θ with an axis passing through the center of the sphere and the center of the hemisphere on a first arc that passes through and intersects a first cross section orthogonal to the holding plane. A receiver for receiving the light emitted from the object to be measured, which is arranged close to each of the opening holes and detected in the opening holes. And means, the opening area of each opening hole, preset to a size corresponding to the spherical zone coefficient in the inclination angle theta.

  According to the above configuration, the light receiving means is provided for each opening hole, and the light intensity received from the measurement object is multiplied by the ball zone coefficient by opening the light in the area corresponding to the weight of the ball zone coefficient in advance. Therefore, the light flux can be obtained by one measurement, and the light flux measurement can be simplified. As a result, light flux measurement that can easily measure the light distribution characteristic without using an integrating sphere is realized.

1 is a vertical sectional view showing a light flux measuring device according to Embodiment 1. FIG. 2A is a plan view of the main body shown in FIG. 1, FIG. 2B is a vertical cross-sectional view taken along line cB-cB in FIG. 2A, FIG. 2C is a bottom view taken in FIG. 2A, and FIG. FIG. It is a graph which shows the change of a spherical zone coefficient when inclination-angle (theta) is 3 degrees, 5 degrees, 10 degrees, and 35 degrees pitch. It is a table | surface which shows the change rate, area, etc. of the spherical zone coefficient when the inclination | tilt angle (theta) is 35 degrees pitch, and the opening area of an opening hole. It is an expanded sectional view which shows the opening hole part of the main-body part shown in FIG. It is a perspective view which shows the light-receiving means of the light beam measuring apparatus which concerns on a modification. 7A is a plan view of the main body of the light flux measuring apparatus according to Embodiment 2, and FIG. 7B is a bottom view of FIG. 7A. It is a perspective view which shows the conventional light radiation pattern measuring apparatus. It is a perspective view which shows the space model in a spherical zone coefficient method. It is a perspective view which shows the light distribution of a light source, and the solid angle of a spherical zone. FIG. 11A is a table showing the spherical zone coefficient when the inclination angle θ is every 10 °, and FIG. 11B is a table showing the spherical zone coefficient when θ is every 5 °. It is a schematic diagram which shows the detection position of the light-receiving part in a spherical zone coefficient method.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, the embodiment described below is an example for embodying the technical idea of the present invention, and the present invention is not limited to the following. Further, the present specification by no means specifies the members shown in the claims to the members of the embodiments. In particular, the dimensions, materials, shapes, relative arrangements, and the like of the component parts described in the embodiments are not intended to limit the scope of the present invention unless otherwise specified, and are merely explanations. It is just an example. Note that the size, positional relationship, and the like of the members shown in each drawing may be exaggerated for clarity of explanation. Furthermore, in the following description, the same name and symbol indicate the same or the same members, and detailed description thereof will be omitted as appropriate. Furthermore, each element constituting the present invention may be configured such that a plurality of elements are configured by the same member and the plurality of elements are shared by one member. It can also be realized by sharing.
(Embodiment 1)

  An example of a light flux measuring apparatus 100 according to Embodiment 1 of the present invention is shown in FIG. The light flux measuring apparatus 100 shown in this figure is bonded to the jig 60 for holding the measurement object WK on the holding plane 62, and is hemispherically recessed on the bonding surface with the jig 60. And a main body 10 having a hemispherical surface 12 formed thereon. The joining position of the jig 60 and the main body portion 10 is positioned in advance so that the measurement object WK is positioned at substantially the center point of the sphere formed by the hemispherical surface 12. A plurality of opening holes 14 are formed in the hemispherical surface 12 of the main body 10. Each opening hole 14 is on the hemispherical surface 12 of the main body 10 and on a first arc passing through the center point of the sphere formed by the hemispherical surface and intersecting the first cross section perpendicular to the holding plane 62. An opening is formed at a position that forms a predetermined inclination angle θ with an axis that is a line connecting the center of the sphere and the center of the hemispherical surface 12. Moreover, the opening area of each opening hole 14 is formed in the magnitude | size according to the spherical zone coefficient in inclination-angle (theta).

  Further, each opening hole 14 is provided with a light receiving means 30 for detecting light emission of the measuring object WK as light distribution measurement data using the opening hole 14 as a detection surface. Furthermore, each light receiving means 30 is integrated and connected to the detecting means 40. Furthermore, the detection means 40 is connected to the output means 50 as necessary.

The light flux measuring apparatus 100 measures the light flux from the measuring object WK disposed on the jig 60 based on the spherical zone coefficient method. That is, the light receiving means 30 is provided for each opening hole 14 and is opened in an area corresponding to the weight of the ball zone coefficient in advance, thereby multiplying the luminous intensity received light emitted from the measuring object WK by the ball zone coefficient. Therefore, the light flux can be obtained by one measurement, and the light flux measurement can be simplified. As a result, light flux measurement that can easily measure the light distribution characteristic without using an integrating sphere is realized. In addition, as the measuring object WK, for example, a light emitting device such as an LED is used. In particular, it is possible to effectively measure a light beam with respect to a point light source having a relatively uniform light distribution characteristic. Hereinafter, each member will be described in detail.
(Jig 60)

  The jig 60 is a member for holding the measurement object WK. Specifically, as shown in FIG. 1, the measurement object WK is arranged at the center of a sphere that is connected to the main body 10 and formed by the hemisphere of the main body 10. The jig 60 includes a connection member for connecting to the main body 10. The connection member can be a post or a screw. In particular, since the main body 10 forms a hemispherical surface 12 that is recessed in a hemispherical shape on the joint surface with the jig 60 as will be described later, the periphery of the hemispherical surface 12 is joined so as to be joined in a region other than the hemispherical surface 12. It is preferable to provide a connection member.

  In addition, in a state where the jig 60 is connected to the main body 10, the main body 10 and the jig 60 are bonded in advance so that the measurement target WK substantially coincides with the center point of the hemispherical sphere. Designed to be. In the example shown in the cross-sectional view of FIG. 1, the jig 60 has a flat joint surface with the main body 10 including the holding flat surface 62, and the joint flat surface is adjusted to be a flat surface that divides the sphere into two parts. . Further, a holding recess 64 is provided in a portion of the holding plane 62 where the measurement object WK is disposed. In a state where the measurement object WK is disposed in the holding recess 64, the light emitting surface of the measurement object WK is designed to substantially coincide with the plane of the joint surface, as shown in the partial enlarged view of FIG. Thereby, the light emission surface of the measuring object WK is made to coincide with the hemispherical center point, and accurate light flux measurement is realized. For fixing the measurement object WK to the holding recess 64, a known holding mechanism such as a double-sided tape or a holding mechanism can be used as appropriate.

1 has a holding plane 62 connected to the end face of a cylindrical shaft 66, and the periphery of the cylindrical shaft 66 and the holding plane 62 is further covered with a covering member 68. The cylindrical shaft body is connected to a holding plane and an energization mechanism for supplying power for lighting the measurement object as necessary. By making the covering member 68 black, light is absorbed and light scattering is suppressed. However, the structure of the covering member is not limited to this example. For example, the covering member may be covered with a black curtain sheet or the like, or the cylindrical shaft body and the holding plane may be colored black to omit the covering member. Further, the entire apparatus may be installed in a dark place, and the covering member may be omitted in the same manner.
(Main body 10)

  As shown in FIGS. 1 and 2, the main body 10 has a disk shape in plan view, and has a hemispherical depression on one surface (bottom surface side). The surface provided with the depression is connected to the jig 60 using a connection member. In the example shown in the bottom view of FIG. 2C, post holes are provided at four corners, and the jig 60 is connected by fitting the post.

The hemispherical surface 12 of the main body 10 is preferably covered with a light-absorbing film. Thereby, reflection of light on the hemispherical surface 12 is suppressed, and accurate light intensity measurement is possible. Or you may perform the surface treatment which suppresses scattering of light. For example, the surface of the metal is surface-treated black. Alternatively, it may be made of black resin.
(Opening hole 14)

  Further, the main body 10 has a plurality of opening holes 14 on the hemispherical surface 12. Each opening hole 14 passes through the center point of the sphere formed by the hemisphere and is on an axis passing through the center of the sphere and the center of the hemisphere 12 on a first arc that intersects the first cross section perpendicular to the holding plane 62. And a predetermined inclination angle θ. Each opening 14 is circular.

When it is assumed that the luminous flux distribution indicated by the light emission of the measurement object is symmetric, the aperture 14 is preferably on the first arc and has an inclination angle θ with respect to the axis in the range of 0 ° to 90 °. . In other words, it is preferably not provided in the range of 0 ° to -90 °. By measuring only one side and presuming that the non-measured side is the same, it is possible to realize a compact light flux measuring apparatus in which the measuring means is unevenly distributed on one side. In the case of measuring a measurement object that exhibits an asymmetrical light flux distribution or more accurate light flux measurement, the inclination angle θ of the aperture 14 is in the range of 0 ° to ± 90 °, and the total is 180 °. Needless to say, light flux measurement can be realized in a range.
(Inclination angle)

The inclination angle θ for forming the opening hole 14 on the hemispherical surface 12 is changed at a constant interval. In the example of FIG. 2, the pitch is 35 °, and opening holes 1414a, 14b, and 14c are opened at three locations of θ ₁ = 0 °, θ ₂ = 35 °, and θ ₃ = 70 °, respectively.

Furthermore, the opening areas of the opening holes 14a, 14b, and 14c opened at each inclination angle have a size corresponding to the spherical zone coefficient at the inclination angle θ. The spherical zone coefficient is a value that is unrelated to the luminous intensity as defined in “JIS C 8105-5: 2014 Lighting Fixture-Part 5: Light Distribution Measurement Method” (Non-Patent Document 1), and for each inclination angle. It can be calculated in advance. As an example, the graph of FIG. 3 shows the result of calculating the ball coefficient for each of the change width of the inclination angle of 3 ° pitch, 5 ° pitch, 10 ° pitch, and 35 ° pitch. The table of FIG. 4 shows the spherical zone coefficient in the case of 35 ° pitch, the magnification of the opening area when the spherical zone coefficient of 0 ° is used as a reference (1.00 times), and the radius and area of the opening hole. . For example, when the tilt angle is 0 °, the spherical zone coefficient is 0.29. The radius of the opening hole also depends on the size of the hemispherical surface 12. In the example of FIG. 1, the radius of the sphere formed by the hemispherical surface 12 is 34 mm, and the radius of the opening hole 14 a opened at the position of the inclination angle θ ₁ (= 0 °) is 4 mm (* how this is determined). Then, the opening area of the opening 14a is 4 mm × 4 mm × circumference≈50.3 mm ² . In addition, the radius of the opening hole 14a is set so that the light receiving part of each opening hole does not overlap from the relationship between the hemispherical outer diameter and the spherical band coefficient.

Next, the area of the opening hole 14b is obtained based on the opening hole 14a. According to FIG. 4, the magnification of the spherical zone coefficient of the opening hole 14b with respect to the spherical zone coefficient of the opening hole 14a is 7.45. Here, in the case of using the integrating sphere, the light intensity is calculated by using the light intensity measured at the opening hole at the position of the inclination angle θ ₂ = 35 ° opened with the same opening area as the reference opening hole 14a. , 7.45 times to obtain. In order to obtain the luminous intensity without performing this multiplication, in other words, in order to obtain the luminous intensity without using the conventional integrating sphere, the opening hole 14b with an inclination angle θ ₂ = 35 ° and the opening hole 14b with θ ₁ = 0 °. It is only necessary to adopt 7.45 times the amount of light received by. That is, the total opening area required for the opening hole 14b is 50.3 mm ² × 7.45≈374.6 mm ² . In the example of FIG. 2C, since the opening holes 14b are opened at two places, the area of each opening hole 14b is 374.6 mm ² ÷ 2 = 187.3 mm ² . Therefore, the radius is calculated as √ (187.3 mm ² ÷ circumference) ≈7.72 mm.

Similarly, when the opening hole 14c with the inclination angle θ ₃ = 70 ° is calculated, the magnification is 12.21. Therefore, the required total opening area is 50.3 mm ² × 12.21≈613.8 mm ² , and each opening The opening area of the hole 14c is half that of 306.9 mm ² . Therefore, the radius is calculated as √ (306.9 mm ² ÷ circumference) ≈9.88 mm.

  Thus, when the pitch of the inclination angle is determined, the radius of the opening hole at each inclination angle is determined from the opening area at the reference position and the ball zone coefficient. Then, by changing the opening area of the aperture hole in accordance with the spherical zone coefficient in this way, it is possible to omit the process of multiplying the luminous intensity measured for each inclination angle, which was conventionally required, by the spherical zone coefficient. Can do. That is, in the conventional method, as shown in FIG. 12, the size of the opening hole 814 is made equal, the light intensity is measured at each position, and then the light intensity obtained at each position is in accordance with the inclination angle of the position. The luminous flux was obtained by multiplying the ball zone coefficient and adding this. With this method, it is necessary to light up the measurement object by the number of apertures and measure the luminous intensity, and there is a problem that the number of measurements increases and the multiplication and addition processes take time. Alternatively, by providing a semiconductor light receiving element such as a PD for each optical fiber provided in the opening hole, the light intensity at each position can be measured by a single measurement, but in this case, the number of light receiving elements required for the number of optical fibers is required. There is a problem that becomes complicated and expensive. Further, since a multiplication process is required for each light receiving element, the load of the process does not change.

On the other hand, according to the present embodiment, by forming an opening area in a size corresponding to the ball zone coefficient in advance, the light intensity detected in this aperture hole is the light quantity multiplied by the ball zone coefficient. Therefore, there is an advantage that it can be used for calculation of the luminous flux as it is. For this reason, it is possible to measure the luminous intensity at each position only by emitting light once on the measurement object, and the advantage is that the number of measurements is one and the measurement time can be shortened. Further, since it is sufficient to bundle the optical fibers 31 as the light receiving means 30 provided in each opening hole and measure the light intensity with one light receiving element, there is an advantage that the configuration can be simplified by reducing the number of light receiving elements. . Furthermore, it is possible to omit the arithmetic processing for multiplying the spherical zone coefficient for each aperture hole, and it is possible to obtain an excellent advantage that light flux measurement is realized at low load, high speed and low cost.
(Light receiving means 30)

  The light receiving means 30 is disposed in each opening hole 14. The light receiving means 30 detects light emission of the measurement object WK detected on the detection surface as light distribution measurement data. For such a light receiving means 30, an optical fiber 31 or the like can be suitably used.

In addition, in this specification, the structure which provides the light-receiving means 30 in all the formed opening holes 14 is demonstrated. However, the light receiving means may not be provided in all the opening holes, or the light receiving means may not be provided in some of the opening holes.
(Detecting means 40)

Each light receiving means 30 is collected in the detecting means 40. As the detection means 40, a semiconductor light receiving element such as a CCD or a light receiving element (PD) is preferably used. Further, it is preferable to use a common detection means in which a plurality of output end faces of the light receiving means having the light receiving end faces positioned in the respective opening holes are connected together. In particular, in a configuration in which the light receiving means 30 is an optical fiber 31 and the detection means 40 is a PD, a plurality of optical fibers 31 are bundled and their emission end faces are optically coupled to the PD, so that a single PD can be used simultaneously. The advantage that the luminous flux can be detected and the configuration can be greatly simplified is obtained.
(Output means 50)

The detection means 40 is connected to the output means 50. The output means 50 outputs the light beam received by the light receiving means 30 and added together by the detecting means 40 to the outside. For example, a display for displaying the luminous flux numerically, a 7-segment display, or the like can be used. In particular, according to the present embodiment, for each element of the light distribution measurement data group obtained by the light receiving means 30 provided in each opening hole as in the prior art, a spherical band corresponding to the angle of each detection surface The process of calculating the luminous flux from the measurement object by multiplying and integrating the coefficient can be greatly reduced.
(Diffusion plate 70)

  Moreover, it is preferable to arrange | position the diffusion plate 70 in each detection hole. By doing in this way, the light taken in the detection hole and entering the detection surface can be made uniform. In particular, the optical fiber 31 that is the light receiving means 30 can receive light only in a certain direction, but can be easily incident on the end face of the optical fiber 31 by making it uniform with the diffusion plate 70.

Further, as shown in the cross-sectional view of FIG. 5, the end face of the optical fiber 31 is preferably separated from the diffusion plate 70 by a distance corresponding to the area of the diffusion plate 70 and the light receiving allowable angle of the optical fiber 31. In this way, light received by the entire surface of the diffusing plate 70 can be incident from the end face of the optical fiber 31.
(Modification)

  In the above example, an optical fiber having the same diameter is used as the light receiving means. However, the area of the end face of the optical fiber can be formed to an area corresponding to the spherical zone coefficient. For example, as shown in the bottom view of the light flux measuring apparatus 100 ′ according to the modification shown in FIG. 6, the area of the end surface exposed to the opening hole 14 is adjusted by bundling a plurality of optical fibers 31 as the light receiving means 30 ′. can do. In this case, since the light can be directly received at the end face of the optical fiber 31, a diffusion plate can be dispensed with.

  In addition, it is preferable that the attitude | position of the jig | tool 60 and the main-body part 10 shall be a vertical attitude | position rather than making the holding | maintenance plane 62 holding the measurement object WK into a horizontal attitude | position. By doing so, for example, even when foreign matter such as dust or dust is generated when placing the measurement object on the jig, such foreign matter is measured compared to the case where the measurement object is placed on a horizontal surface. It is possible to avoid a situation in which the accuracy of measurement decreases due to adhesion to the light emitting surface of an object.

  Furthermore, it is preferable that the opening 14 is also in a posture in which the detection surface of the light receiving means 30 is directed vertically downward. Specifically, the opening hole 14 is not opened upward, but as far as possible, preferably between the horizontal posture and vertically downward, that is, so that the angle with the horizontal plane is 0 ° to 90 °. By doing in this way, since the detection surface of the light receiving means 30 arranged in the opening hole 14 is fixed in a posture that is vertically downward from the horizontal plane, it is possible to avoid a situation where dust or dust adheres to the detection surface.

  By doing so, as shown in the cross-sectional view of FIG. 1, the measurement object WK is held vertically while the main body 10 and the jig 60 are joined, and each light receiving means 30 has a horizontal detection surface. It is arrange | positioned downward and it can avoid the situation where foreign materials, such as dust, adhere to an optical member, and can improve the light beam measurement precision. In particular, the conventional light flux measurement method using an integrating sphere measures the light flux by reflecting light from the inner surface of the integrating sphere, so if foreign matter such as dust or dust enters the surface of the integrating sphere, the amount of light will be weakened and measured. There was a problem that the accuracy decreased. On the other hand, according to the present embodiment, it is possible to avoid such a problem and improve the reliability of the light flux measurement result by adopting a posture in which a foreign object hardly adheres to the measurement object or the opening hole.

In the first embodiment, the opening hole 14, that is, the light receiving means 30 is provided not only on the first arc as shown in FIG. 2 but also on the second arc intersecting therewith. That is, as shown in the bottom view of FIG. 2C, the opening hole 14 is opened on the first arc and also on the second arc intersecting therewith. In other words, the opening hole is formed on the radius of 0 ° and 90 ° from the center of the hemispherical surface 12 in plan view. Specifically, the axis line and a predetermined inclination angle θ are also formed on a second arc that passes through the center of the hemispherical surface 12 of the main body 10 and intersects the second cut surface and the hemispherical surface 12 that are orthogonal to the first cross section. A plurality of second opening holes 15 that are opened at positions that define the above are defined. This light beam measuring apparatus 100 adds the light beam obtained by averaging the light beam obtained at the first cross section and the light beam obtained at the second cut surface by the detection means 40 and outputs the result as a measurement result from the output unit. In this way, even when the measurement object does not have an axially symmetric light distribution, the total luminous flux can be obtained by averaging the luminous fluxes obtained in the vertical direction. For example, in the case of an LED, the luminous flux is not a perfect circle, but is slightly elliptical. Thus, by using the luminous flux measurement in which the luminous flux is measured in two directions in plan view, it is possible to obtain a more accurate luminous intensity. .
(Embodiment 2)

However, the present invention is not limited to the configuration in which the opening hole, that is, the light receiving means is provided on the two arcs of the first arc and the second arc, but may be provided on three or more arcs. As an example, a light flux measuring apparatus 100 in which an opening hole is also opened on a third arc is shown in FIG. Here, as shown in the bottom view of FIG. 7B, opening holes are formed on radii of 0 °, 45 °, and 90 ° from the center of the hemispherical surface 12 in plan view. Specifically, in addition to the first arc and the second arc, the third cut surface that passes through the center of the hemispherical surface 12 of the main body 10 and equally divides the angle formed by the first cross section and the second cut surface. A plurality of third opening holes 16 are also formed on the third arc where the hemispherical surface 12 and the hemispherical surface 12 intersect at a position that forms a predetermined inclination angle θ with the axis. In this light beam measuring apparatus 100, the light beam obtained by averaging the light beams obtained at the first cross section, the second cut surface, and the third cut surface is added by the detection means 40 and output. With such a configuration, even when the measurement object does not have an axially symmetric light distribution, the total luminous flux can be obtained by averaging the luminous fluxes obtained at the respective cut surfaces.
(Embodiment 3)

  Or conversely, the opening hole, that is, the light receiving means may be provided only on the first arc. In particular, it can be suitably used for a case where the symmetry of the light flux distribution of the measurement object is high, a use that does not require such a high degree of accuracy, or a use such as simple light flux measurement.

  The light flux measuring apparatus and the light flux measuring method of the present invention can be suitably used as an inspection device for measuring the light flux of a light source for illumination use or backlight use such as LED, semiconductor laser (LD), and organic EL.

DESCRIPTION OF SYMBOLS 100, 100 ', 200 ... Luminous flux measuring apparatus 10 ... Main-body part 12 ... Hemispherical surface 14, 14a, 14b, 14c ... Opening hole 15 ... Second opening hole 16 ... Third opening hole 30, 30' ... Light-receiving means 31 ... Light Fiber 40 ... Detection means 50 ... Output means 60 ... Jig 62 ... Holding plane 64 ... Holding depression 66 ... Cylindrical shaft body 68 ... Cover member 70 ... Diffusion plate 800 ... Light emission pattern measuring devices 830a to 830e ... Light receiving part 814 ... Opening hole 840 ... Detector WK ... Measurement object

Claims (9)

A light flux measuring device for measuring a light flux from a measurement object based on the spherical zone coefficient method,
A jig for holding the measurement object on the holding plane;
A hemispherical surface is formed in a hemispherical shape on the joint surface with the jig, and held on the holding plane of the jig at the center of the sphere formed by the hemispherical surface. A main body for placing the measured object,
The center of the sphere and the hemisphere are on a first arc on the hemispherical surface of the main body and passing through the center of the sphere formed by the hemispherical surface and intersecting the first cross section perpendicular to the holding plane. A light receiving means for receiving light emitted from a measurement object that is disposed in proximity to each of a plurality of opening holes that are opened at positions that form a predetermined inclination angle θ with an axis that passes through the center of the opening. When,
With
A luminous flux measuring apparatus, wherein an opening area of each opening hole is preset to a size corresponding to a spherical zone coefficient at an inclination angle θ. The light flux measuring device according to claim 1,
The light beam measuring device, wherein the light receiving means is an optical fiber. The light flux measuring device according to claim 2, further comprising:
A light flux measuring apparatus comprising a diffusion plate disposed in the opening hole. The light flux measuring device according to claim 3,
A light flux measuring apparatus, wherein the end face of the optical fiber is separated from the diffuser plate by a distance corresponding to the area of the diffuser plate and the light receiving allowable angle of the optical fiber. It is a light beam measuring apparatus as described in any one of Claims 1-4,
The jig is held in a posture in which the holding plane is vertical;
Further, the plurality of aperture holes are opened such that the detection surface of the light receiving means arranged here is fixed in a posture in which the detection surface faces vertically downward from a horizontal plane. The light flux measurement device according to any one of claims 1 to 5,
The luminous flux measuring apparatus, wherein the opening hole is provided with an inclination angle θ with respect to the vertical direction of the center of the hemisphere at 0 °, 35 °, and 70 °. The light flux measurement device according to any one of claims 1 to 6,
The luminous flux measuring apparatus characterized in that the hemispherical surface is covered with a light-absorbing film. The light flux measurement device according to any one of claims 1 to 7,
A light flux measuring apparatus, wherein the object to be measured is a light emitting diode. A luminous flux measurement method for measuring a luminous flux from an object to be measured based on the spherical zone coefficient method,
Holding the measurement object on the holding plane with a jig;
The object to be measured held on the holding plane of the jig is arranged at the center of the sphere formed by the hemispherical surface of the hemispherical concave spherical surface of the main body joined to the jig. Illuminate the measurement object
The center of the sphere and the hemispherical surface are on a hemispherical surface of the main body and on a first arc passing through the center of the sphere formed by the hemispherical surface and intersecting a first cross section perpendicular to the holding plane. With light receiving means arranged close to each of a plurality of apertures that are opened at positions that form a predetermined inclination angle θ with an axis passing through the center, the light emission of the measurement object detected in the apertures is received, The plurality of opening holes are designed to have an opening area with a size corresponding to the spherical zone coefficient at the inclination angle θ ,
And adding a luminous intensity obtained by each light receiving means to output a luminous flux.

Images