JP6592279B2 - Chromaticity inspection method and inspection device for light emitting device - Google Patents

Description

  The present invention relates to a technique for inspecting a light emitting device including a plurality of light emitting elements, and more particularly to a technique for inspecting appropriateness of chromaticity of a plurality of light emitting elements, in particular, chromaticity variation (color unevenness).

  As a light emitting device, a vehicle lamp using a light emitting element such as a light emitting diode (LED) as a light source is provided. In many cases, this type of lamp has a configuration in which a plurality of LEDs are arranged in a lamp housing in order to obtain a required luminous intensity. For example, in an automobile fog lamp, four LEDs are arranged in a lamp housing having a translucent front lens, and the four LEDs are caused to emit light simultaneously, and light emitted from each LED is emitted through the front lens. The configuration is taken. Thereby, the luminous intensity of the whole fog lamp is increased, and a lamp satisfying the required luminous intensity is obtained.

  In such a lamp using a plurality of LEDs as light sources, there is a variation in the chromaticity of light emitted from each LED (sometimes referred to as hue or color tone, but referred to as chromaticity in this specification). When the lamp is viewed from the front side when the lamp is turned on, color unevenness is observed on the surface of the front lens, which causes a problem in the quality of the lamp. Therefore, when manufacturing a lamp, it is necessary to inspect the chromaticity of a plurality of LEDs to prevent the occurrence of color unevenness.

  When the inspector inspects the color unevenness, the color unevenness is determined by the inspector's subjectivity. Therefore, it is difficult to determine with high reproducibility whether the color unevenness of the manufactured lamp is within the standard. Therefore, it is desired to automatically inspect the color unevenness.

  As a technique for inspecting color unevenness caused by a plurality of LEDs, for example, there is a technique disclosed in Patent Document 1. This technology captures a light diffuser illuminated by a plurality of LEDs, divides the obtained image into pixels, separates the color, and then photoelectrically converts the chromaticity distribution consisting of position information and chromaticity information for each pixel. I have data. With this chromaticity distribution data, it is possible to detect variations in chromaticity in the light diffusion plate, that is, color unevenness, and to achieve illumination without color unevenness by adjusting the chromaticity to be within a predetermined range. Can do.

JP 2006-98054 A

  The technique of Patent Document 1 obtains chromaticity information by performing color separation for each pixel of a captured image, but there is no description of a specific method in Patent Document 1 for this color separation, Usually, it is considered that the pixel is decomposed into color elements of three primary colors of RGB. In addition, Patent Document 1 photoelectrically converts each of the decomposed color elements to obtain luminous intensity, and obtains chromaticity based on the luminous intensity of these color elements. Therefore, in the technique of Patent Document 1, the process for obtaining the chromaticity of a plurality of LEDs is complicated, the processing time becomes long, and the apparatus for detecting the chromaticity cannot be complicated. Absent.

  SUMMARY OF THE INVENTION An object of the present invention is to provide a chromaticity inspection method and an inspection apparatus for a light-emitting device that simplify inspection processing for determining variations in chromaticity and simplify the inspection apparatus.

Chromaticity inspection apparatus of the present invention is an inspection apparatus for inspecting the chromaticity of emission color of a light-emitting device comprising a plurality of light sources, each light source and the light-emitting element that emits blue light is excited by the blue light comprising a phosphor emitting yellow light, by mixing these blue light and yellow light Ri configuration der that emits pseudo white light, and the blue light region of the first wavelength region, a green light as the second wavelength region Means for measuring each luminous intensity of the region to detect the first and second photometric values; chromaticity value calculating means for calculating the chromaticity value of each light source from the first and second photometric values; Relative value calculation means for calculating the relative value of each chromaticity value of each light source, and determination means for determining the suitability of the chromaticity of the emission color based on the relative value.

  In the first aspect of the present invention, the relative value calculating means is a means for calculating the difference between the maximum value and the minimum value of the chromaticity values of the respective light sources, and the determining means is the chromaticity when the difference is not more than a predetermined value. Means for determining appropriateness are provided.

  According to a second aspect of the present invention, the relative value calculating means calculates an average value of chromaticity values of each light source, and further calculates a relative value of each chromaticity value with respect to the average value. Means for determining that the chromaticity is appropriate when each relative value is within a predetermined first range. In the second embodiment, the determination unit may further include a unit that determines that the chromaticity is appropriate when the average value is within a predetermined second range.

Chromaticity inspection method of the present invention is an inspection method for inspecting the chromaticity of emission color of a light-emitting device comprising a plurality of light sources, each light source and the light-emitting element that emits blue light is excited by the blue light comprising a phosphor emitting yellow light, by mixing these blue light and yellow light Ri configuration der that emits pseudo white light, and the blue light region of the first wavelength region, a green light as the second wavelength region A step of measuring each luminous intensity of the region to detect a first photometric value and a second photometric value; a step of calculating a chromaticity value of each light source from the first photometric value and the second photometric value; and a color of each light source A step of calculating a relative value of the degree value, and a step of determining suitability of the chromaticity of the emission color based on the relative value.

  According to the present invention, the first photometric value and the second photometric value are detected by measuring the respective light intensities in the first wavelength region and the second wavelength region, and the chromaticity value is determined from the first photometric value and the second photometric value. It is possible to check the suitability of chromaticity by calculating and further calculating the relative values of chromaticity values of a plurality of light sources. Therefore, the photometric means can be simply configured, the photometric man-hours can be reduced, and the processing of the calculation unit based on the photometric value can be simplified to easily and quickly perform the chromaticity inspection.

The schematic perspective view of a fog lamp as a test object, a longitudinal cross-sectional view, and a front view. The schematic sectional drawing of LED, and its spectral characteristics figure. The figure which plotted the spectral characteristic figure and chromaticity value of LED from which chromaticity differs. 1 is a schematic configuration diagram of a chromaticity inspection apparatus according to an embodiment. The figure explaining the simple inspection method of chromaticity. The figure explaining the exact inspection method of chromaticity. The figure explaining the dispersion | variation inspection of the chromaticity between several fog lamps. The schematic block diagram of the chromaticity inspection apparatus of other embodiment. Furthermore, the schematic block diagram of the chromaticity test | inspection apparatus of other embodiment.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a fog lamp FL of an automobile as a light emitting device to be inspected by the chromaticity inspection apparatus of the present invention. FIG. 1 (a) is a schematic perspective view of the fog lamp FL, and FIG. It is a longitudinal cross-sectional view. As will be described later, this embodiment is configured as an inspection apparatus for inspecting chromaticity variation, that is, color unevenness, on the light emitting surface of the fog lamp FL.

  The fog lamp FL includes four light emitting elements, here four light emitting diodes (hereinafter referred to as LEDs) 1a to 1d as light sources. The LEDs 1a to 1d are mounted on the required substrates 2a to 2d, respectively, and are configured as LED modules 3a to 3d that emit power by being fed through the substrates 2a to 2d. These LED modules 3a to 3d are fixedly supported on a base plate 5 disposed in the lamp body 4 of the fog lamp FL. The base plate 5 is fixed and supported in a state of extending in the left-right direction at a substantially central position in the vertical direction in the lamp body 4, and the four LED modules 3 a to 3 d are mounted on the upper and lower surfaces of the base plate 5. Two each are fixedly supported at a position spaced apart in the left-right direction.

  The inner surface of the lamp body 4 is configured as a reflector surface 41. When the four LEDs 1a to 1d emit light, the light emitted from the LEDs 1a to 1d is reflected by the reflector surface 41, and the lamp housing body. 4 is transmitted through the front lens 6 having translucency disposed in the front opening 4 and irradiated to the front region.

  In this fog lamp FL, when the fog lamp FL is viewed from the front direction, that is, from the front when illuminated, the light emitted from the four LEDs 1a to 1d is reflected by the reflector surface 41, as shown in FIG. When the light is transmitted forward through the front lens 6, four light emitting areas Aa to Ad that divide the front lens 6 vertically and horizontally are observed. Therefore, the light emitting surface as a whole of the fog lamp FL is composed of these four light emitting areas Aa to Ad.

  The LEDs 1a to 1d used in the LED modules 3a to 3d are so-called pseudo white LEDs. As shown in FIG. 2A, the pseudo white LED has a schematic cross-sectional structure as LED 1 and a blue LED chip 12 that emits blue light is mounted in a package case 11 having a rectangular concave dish shape. The yellow phosphor 13 that emits yellow light when excited by the blue light is arranged in the package case 11 so as to cover the blue LED chip 12. As shown in FIG. 2B, the spectral distribution of the pseudo white LED includes blue light emitted from the blue LED chip 12 having a peak at a wavelength of about 450 nm and a wavelength of about 550 nm generated by the yellow phosphor 13. It has spectral characteristics in which yellow light having a gentle peak is photomixed.

  In the LED 1 having this configuration, due to the relative relationship between the luminous intensity when the blue light emitted from the blue LED chip 12 is emitted through the yellow phosphor 13 and the luminous intensity of the yellow light generated by the yellow phosphor 13. The chromaticity of the light emitted from the LED 1 is determined. That is, in FIG. 2B, the luminous intensity LB in the first wavelength region (blue light wavelength region: hereinafter referred to as B wavelength region) and the luminous intensity LG in the second wavelength region (green light wavelength region: hereinafter referred to as G wavelength region). The chromaticity is determined by the light intensity LR in the third wavelength region (red light wavelength region: hereinafter, R wavelength region). Therefore, when these luminosities are different, the chromaticity is also different.

  If the chromaticity of each LED 1 is different due to the difference in the luminous intensity of these first to third wavelength regions, the chromaticity of the four LEDs 1a to 1d of the fog lamp FL varies, and the colors of the four light emitting regions Aa to Ad. Variations will occur in the degree. If the variation in chromaticity is a difference that cannot be distinguished with the naked eye, uneven color due to the difference in chromaticity in the four light emitting areas Aa to Ad is not observed. On the other hand, if the chromaticity of one or two of the four LEDs 1a to 1d is different from the chromaticity of the other LEDs to such an extent that it can be observed with the naked eye, one of the four light emitting areas Aa to Ad or Color unevenness is observed in the two light emitting regions. When this uneven color is observed, it is determined that the chromaticity of the fog lamp FL is not appropriate.

  According to the study of the present inventor, it has been found that this type of LED can be classified as an LED having three different chromaticity forms. That is, an LED that emits light with a standard white chromaticity (W-LED), an LED that emits light with a bluish blue-based white chromaticity (B-LED), and a yellowish yellow-green white LED (G-LED) that emits light with chromaticity.

  FIG. 3A is a spectral characteristic diagram of LEDs of these three chromaticities. For these LEDs, the luminous intensity LB (LBw, LBb, LBg) in the B wavelength region, the luminous intensity LG (LGw, LGb, LGg) in the G wavelength region, and the luminous intensity LR (LRw, LRb, LRg) in the R wavelength region. It was measured. Then, when the measured luminosity was compared with the chromaticity of each LED, the following was found. That is, in each LED, there is a difference between the light intensity LB in the B wavelength region and the light intensity LG in the G wavelength region. On the other hand, there is no significant difference in the luminous intensity LR in the R wavelength region between the LEDs.

  From this, the present inventor has conceived that it is possible to inspect the difference in chromaticity of each LED by measuring the luminosity LB, LG in the B wavelength region and the G wavelength region. In particular, it is found that the light intensity ratio between the light intensity LB and LG in the B wavelength region and the G wavelength region has a correlation with the chromaticity, and from this, the light intensity ratio can be used as it is as the chromaticity value CV. I came up with it. This chromaticity value (luminosity ratio) is calculated by the calculation formula CV = LB / LG.

  The chromaticity value CV is calculated by the above-described arithmetic expression for the three types of LEDs shown in FIG. 3A, that is, W-LED, B-LED, and G-LED, and the ordinate indicates the chromaticity coordinates. When plotted, the result is as shown in FIG. The chromaticity value CV is a reference white chromaticity when the chromaticity value CV is a predetermined value. When the chromaticity value CV is larger than this, a bluish blue chromaticity is obtained. Tasteful yellow-green chromaticity.

  FIG. 4 is a block diagram of the chromaticity inspection apparatus CT according to the embodiment configured based on such a view. The photometric unit 110 is for measuring light emitted from the fog lamp FL as an inspection target, and is on the front side of the milky white light transmission diffuser plate 110 disposed in front of the fog lamp FL, that is, on the opposite side to the fog lamp FL. Are arranged so as to face the four light emitting areas Aa to Ad of the fog lamp FL. The photometric unit 110 has four optical sensor pairs 112a to 112d, and the four optical sensor pairs 112a to 112d are respectively a B sensor SB that measures light in a B wavelength region as a first wavelength region, and The G sensor SG is configured to measure light in the G wavelength region as the second wavelength region. The B sensor SB photoelectrically converts the received light in the B wavelength region and outputs a first photometric value (B photometric value) LB, and the G sensor SG photoelectrically converts the received light in the G wavelength region to perform second photometry. A value (G photometric value) LG is output.

  In addition, the chromaticity inspection apparatus CT includes a calculation unit 100 for performing calculation on the measured B photometric value LB and G photometric value LG. The computing unit 100 computes a relative ratio between the B photometric value LB and the G photometric value LG and calculates this as a chromaticity value, and these chromaticity value computing units 101a. An average value calculation unit 102 that calculates an average value of chromaticity values obtained at ˜101d, and a relative value calculation that calculates a relative difference between the chromaticity values obtained at the chromaticity value calculation units 101a to 101d as relative values Part 103.

  Further, the chromaticity inspection apparatus CT determines a suitability of chromaticity in the fog lamp FL to be inspected, that is, a chromaticity variation, based on the average value or the relative value calculated by the calculation unit 100. It has. As will be described in detail later, the determination unit 120 includes a relative value determination unit 121 that determines whether or not the relative value is within a predetermined reference value range, and the average value is a predetermined reference average value range. An average value determination unit 122 is provided for determining whether or not it exists in the inside.

  A chromaticity inspection method using the chromaticity inspection apparatus CT having this configuration will be described. As shown in FIG. 4, the fog lamp FL as an inspection object is turned on, and a light transmission diffusion plate 111 is disposed on the front side thereof with a required dimension apart. Then, on the front side of the light diffusing plate 111, that is, on the side opposite to the fog lamp FL, the illumination area of the light diffusing plate 111 illuminated by the light emitted from the fog lamp FL being transmitted in a diffused state, that is, the fog lamp FL The four illumination areas (hereinafter also referred to as light emission areas Aa to Ad) corresponding to the four light emission areas Aa to Ad are measured by the four optical sensor pairs 112a to 112d, respectively.

  The B photometric values LB and G photometric values LG measured by the B sensor SB and G sensor SG of each of the photosensor pairs 112a to 112d have a luminous intensity ratio between the photometric values LB and LG in the chromaticity value calculation units 101a to 101d, respectively. Calculated. This is as shown in FIG. 3B, and the chromaticity calculation units 101a to 101d are configured such that the B photometric value of the B sensor SB is LB, the G photometric value of the G sensor SG is LG, and CV = LB / LG. Perform the operation. This is performed for the four light emitting areas Aa to Ad to obtain respective chromaticity values CVa to CVd.

  These four chromaticity values CVa to CVd are plotted on the chromaticity chart shown in FIG. 5A (a). In this chromaticity chart, the vertical axis is the chromaticity value (relative ratio) as in FIG. 3B, and when the upper chromaticity value increases, it is bluish blue white, and the chromaticity value is When it gets smaller, it is yellowish yellowish white with yellowishness. When the four chromaticity values CVa to CVd are different from each other, the plot position of each chromaticity value is different in the vertical coordinate position, and the vertical coordinate position is the color in each light emitting area Aa to Ad. It represents the difference in degrees.

  As a first inspection in the present invention, the relative value calculation unit 103 detects the maximum value and the minimum value of the calculated chromaticity values and calculates the difference between them. In FIG. 5A (a), the chromaticity value CVb is the maximum value, and the chromaticity value CVc is the minimum value. A difference Dx between these chromaticity values is CVb-CVc.

  Then, in the determination unit 120, the relative value determination unit 121 compares the chromaticity difference Dx with the reference value Dr. If the difference Dx is less than or equal to the reference value Dr, the chromaticity values CVa to CVd of the four light sources are all within the range of the reference value Dr. Therefore, it is determined that no color unevenness due to chromaticity variation has occurred. On the other hand, when the difference Dx is larger than the reference value Dr, any one of the chromaticity values CVa to CVd of the four light sources is outside the range of the reference value Dr. Is done.

  For example, in the case of FIG. 5A (b), the chromaticity value CVd is the maximum value, the chromaticity value CVc is the minimum value, and the difference Dx between them is equal to or less than the reference value Dr. Determined. In the case of FIG. 5A (c), similarly, the chromaticity value CVd is the maximum value and the chromaticity value CVc is the minimum value, but since the difference Dx between them is larger than the reference value Dr, color unevenness occurs. It is determined.

  In this inspection method, the calculation unit 100 only needs to perform the calculation in the relative value calculation unit 103 on the calculated chromaticity values CVa to CVd, and the determination unit 120 performs the determination in the relative value determination unit 121. Since only this is necessary, rapid inspection can be realized.

  In this first inspection method, when the four chromaticity values CVa to CVd are biased, for example, three chromaticity values are biased to blue, and one chromaticity value is biased to yellowish green. In such a case, the yellowish green light source becomes conspicuous with respect to the blue light source, which may cause color unevenness.

  Therefore, in the present invention, it is possible to execute the second inspection with higher reliability. As shown in FIG. 5B (a), the calculated four chromaticity values CVa to CVd are plotted on a chromaticity chart. This chromaticity chart is the same as FIG. 5A (a).

  Next, in the second inspection, the average value calculation unit 102 calculates the average value M of the chromaticity values CVa to CVd. The average value M indicates whether the average of the chromaticity of the four light emitting areas Aa to Ad is present between blue white and yellow green white. Further, the relative value calculation unit 103 calculates the relative values Da to Dd of the four chromaticity values CVa to CVd with respect to the average value M. The relative values Da to Dd take the difference between the average value M and each chromaticity value CVa to CVd, and how much each chromaticity value is on the blue side or yellowish green side with respect to the average value M. Will be shown.

  Accordingly, in the determination unit 120, the relative value determination unit 121 determines whether or not these four relative values Da to Dd exist between the upper limit and the lower limit of the predetermined reference relative value range REF1. The reference relative value range REF1 is a value that is set recursively based on a large number of measurement results obtained in advance in preliminary experiments. The chromaticity is in the blue and yellowish green directions with respect to the average value M. It shows the upper and lower limits where the difference in chromaticity cannot be confirmed with the naked eye even when they are different. This reference relative value range REF1 is the first range in the present invention. Note that the upper and lower limits are not necessarily in the same range in the vertical direction with respect to the average value M.

  In the example of the fog lamp in FIG. 5B (a), the four relative values Da to Dd are all smaller than the upper limit of the first range REF1 and larger than the lower limit, so that the chromaticities of the four light emitting areas Aa to Ad of the fog lamp FL The variation does not stand out, and it is determined that no color unevenness has occurred. The same applies to the fog lamp shown in FIG. 5B (b). The relative values Da to Dd of the four chromaticity values CVa to CVd are all smaller than the upper limit of the first range REF1 and larger than the lower limit. The variation in chromaticity of the four light emitting areas Aa to Ad of the fog lamp FL does not stand out and it is determined that no color unevenness occurs.

  On the other hand, in the case of the fog lamp of FIG. 5B (c), among the relative values Da to Dd of the four chromaticity values CVa to CVd, the relative value Dc in the chromaticity value CVc is smaller than the lower limit of the first range REF1. It is a value. That is, the chromaticity of the light emitting area Ac is white with a strong yellowish green color with respect to the other light emitting areas Aa, Ab, and Ad, and there is a significant difference in chromaticity. Therefore, in this fog lamp, it is determined that color unevenness due to chromaticity variation occurs in one of the four light emitting areas Aa to Ad.

  Thus, the color unevenness in the four light emitting areas Aa to Ad in the fog lamp can be inspected by the inspection using the chromaticity inspection apparatus CT of the embodiment. In this chromaticity inspection apparatus CT, since the photometry unit 110 can be configured by a pair of optical sensors 112a to 112d including a B sensor SB and a G sensor SG, three BGR optical sensors for inspecting the spectral characteristics of the three primary colors are required. The configuration is simpler than the photometric unit.

  Further, in the color unevenness determination process, a calculation process for obtaining the respective light intensity ratios for a plurality of light sensor pairs is performed, and a difference between the plurality of light intensity ratios obtained in the first inspection is calculated and compared with a reference value. It is only necessary to perform an arithmetic process, and it is only necessary to perform an average value calculation process based on a plurality of light intensity ratios obtained in the second inspection and a relative value calculation process for the average value. Therefore, as in Patent Document 1, RGB spectrophotometry is performed in correspondence with a plurality of LEDs, chromaticity is calculated based on each RGB photometric value, and variation of the obtained chromaticity is calculated. Such a complicated process becomes unnecessary. Thereby, the structure of the calculating part of a test | inspection apparatus can be simplified. In addition, since the processing time can be shortened by simplifying the process, the color unevenness inspection apparatus according to the embodiment can be incorporated in the fog lamp production line.

  The above inspection is an example in which variation in chromaticity in the four light emitting areas Aa to Ad of one fog lamp is inspected. As described above, the variation in chromaticity of the four light emitting regions is based on the difference in chromaticity values of the respective light emitting regions or the relative difference (relative value) of the chromaticity values of the respective light emitting regions with respect to the average value of the chromaticity values. It is calculated as variation. Therefore, even when the chromaticity values of the four light emitting regions are all biased toward either the blue side or the yellowish green side, the chromaticity value difference Dx is equal to or less than the reference value Dr, and is a relative value with respect to the average value. May fall within the first range REF1, that is, the reference relative value range. In this case, chromaticity variation is not detected in each fog lamp.

  However, when chromaticity inspection is performed on a plurality of fog lamps, no variation in chromaticity between the four light emitting areas is detected in each fog lamp, but there is a variation in chromaticity between the plurality of fog lamps. May occur. That is, no variation in chromaticity in the four light emitting areas is detected with one fog lamp, but when a plurality of different fog lamps are compared, the overall emission color of each fog lamp becomes blue chromaticity, or yellowish green It becomes the chromaticity of the system. This variation in chromaticity may cause a problem in terms of the total quality of the manufactured plurality of fog lamps.

  In view of such variations in chromaticity, in the inspection apparatus CT of the embodiment, the average value determination unit 122 of the determination unit 120 compares the average value M of the chromaticity values of the individual fog lamps with each other. FIG. 6 is a chromaticity chart for explaining this, and plots chromaticity values in each of four light emitting regions of a plurality of fog lamps, here, the first to fourth fog lamps FL1 to FL4. In this example, in the second fog lamp FL2, it can be seen that the average value M2 of the chromaticity values of the four light emitting regions is larger than the average value M1 of the first fog lamp FL1, and the chromaticity is biased toward blue. . In contrast, in the third fog lamp FL3, the average value M3 of the chromaticity values of the four light emitting regions is smaller than the average value M1 of the first fog lamp FL1, and it can be seen that the chromaticity is biased to yellowish green. It can be seen that the average value M4 of the fourth fog lamp FL4 is smaller, and the chromaticity is more biased toward yellowish green than the third fog lamp FL3.

  In any of these first to fourth fog lamps FL1 to FL4, the relative values Da to Dd of the chromaticity values in the respective four light emitting regions are within the upper and lower limits of the first range REF1. Therefore, the chromaticity variation is not determined in each of the fog lamps FL1 to FL4. However, these four fog lamps FL1 to FL4 are different as described above when the average values M1 to M4 are compared. Therefore, the second fog lamp FL2 has a chromaticity that is bluer than that of the first fog lamp FL1. The third and fourth fog lamps FL3 and FL4 have a yellowish green chromaticity than that of the first fog lamp FL1.

  In this inspection apparatus CT, the average value determination unit 122 refers to the average value of each fog lamp as a preset reference average value range REF2, and whether or not the average value of each fog lamp exists in the reference average value range REF2. Determine. This reference average value range REF2 is the second range in the present invention. In the example of FIG. 6, for the first to third fog lamps FL1 to FL3, the average values M1 to M3 are within the range of the second range REF2.

  On the other hand, in the fourth fog lamp FL4, the average value M4 deviates from the second range REF2. Therefore, in this case, it is determined that there is chromaticity variation for the fourth fog lamp FL4. Thereby, it is possible to inspect the chromaticity variation of the fourth fog lamp FL4 whose chromaticity is significantly yellowish green with respect to the first to third fog lamps FL1 to FL3, and manufacture a plurality of fog lamps. Even in this case, variation in chromaticity among the plurality of fog lamps can be avoided.

  FIG. 7 is a conceptual configuration diagram of a chromaticity inspection apparatus according to another embodiment, and parts equivalent to those in FIG. In this embodiment, the photometry unit 110A includes one optical sensor pair 112, that is, one B sensor SB and one G sensor SG. In addition, an actuator 113 for moving the optical sensor pair 112 in the plane direction with respect to the light transmission diffusion plate 111 is provided. The actuator 113 moves the optical sensor pair 112 to the four light emitting areas Aa to Ad. It is comprised so that it can oppose in order.

  On the other hand, the computing unit 100 is provided with only one chromaticity value computing unit 101 that computes the relative ratio between the B photometric value LB and the G photometric value LG. Instead, the chromaticity value calculation unit 101 is provided with a storage unit 104, and the photometric value LB obtained when the photosensor pair 112 is moved to each of the four light emitting areas Aa to Ad to perform photometry. LG and the chromaticity value CV calculated based on the photometric values LB and LG can be stored in the storage unit 104, respectively. Accordingly, the calculation unit 100 sequentially reads the photometric values LB and LG and the chromaticity values CV for the four light emitting areas Aa to Ad stored in the storage unit 104 while the average value calculation unit 102 and the relative value calculation unit 103 Arithmetic is executed. The determination unit 120 determines the chromaticity variation from the calculated average value and relative value as in the above embodiment.

  In this embodiment, since only one optical sensor pair 112 is required, the configuration of the photometric unit 110A including the optical sensor pair 112 can be simplified with respect to the configuration excluding the actuator 113. In addition, since only one chromaticity value calculation unit 101 in the calculation unit 100 is required, the configuration of the calculation unit 100 can be simplified. Thereby, the whole structure of the inspection apparatus CT can be simplified.

  FIG. 8 is a conceptual configuration diagram of a chromaticity inspection apparatus CT of still another embodiment, and the same reference numerals are given to the parts equivalent to FIG. In this embodiment, an image pickup apparatus using an image pickup device is used as the photometry unit 110B. Here, a color digital camera 114 that captures a still image is used, and the four light emitting areas Aa to Ad in the light transmission diffusion plate 111 are collectively captured by the color digital camera 114. The color image sensor 115 of the color digital camera 114 is connected to the arithmetic unit 100 similar to the chromaticity inspection apparatus CT shown in FIG.

  In addition, a part of a large number of light receiving cells (light receiving elements) constituting the color image sensor 115 is set as a B sensor SB and a G sensor SG, and these constitute four optical sensor pairs 112. . These optical sensor pairs 112 are set to areas for imaging each of the four light emitting areas Aa to Ad when the light transmission diffusion plate 111 is imaged. Therefore, when the four light emitting areas Aa to Ad are imaged, the B photometric values and the G photometric values of the four light emitting areas Aa to Ad are obtained from the four photosensor pairs 112, respectively.

  The calculation unit 100 has the same configuration as the chromaticity inspection apparatus CT in FIG. Since each photometric value measured by the four optical sensors 112 set in the color image sensor 115 is output in time series, the chromaticity calculation unit 101 of the calculation unit 100 calculates the calculated photometric value and the calculated value. By storing the obtained chromaticity value in the storage unit 104, it is possible to execute computation and determine the chromaticity similarly to the chromaticity inspection apparatus CT of FIG.

  In this embodiment, since an existing color digital camera, color digital movie camera, or the like can be used, the configuration of the photometry unit can be simplified. In addition, if a calculation unit and a determination unit are incorporated in these cameras, a chromaticity inspection device can be constructed in the camera, which is effective in reducing the size of the chromaticity inspection device.

  In the embodiment, since an example in which a pseudo white LED is used as an LED to be inspected has been described, an example of a blue wavelength region as a first wavelength region and a green wavelength region as a second wavelength region in the present invention has been described. According to the difference in the light emission characteristics, it is possible to inspect chromaticity variations using other wavelength regions. For example, in the case of a three-primary white LED composed of three BGR LED chips, or an LED composed of an ultraviolet LED chip and a BGR phosphor, a blue wavelength region as the first wavelength region and a red wavelength as the second wavelength region It is also possible to apply a region.

  Also, depending on the type of LED, even if the chromaticity of each LED varies, the photometric value in the second wavelength region of each LED is large as in the third wavelength region as described above. Some do not change. When the present invention is applied to such an LED, if the photometric value in the second wavelength region is measured in advance, the photometric value in the second wavelength region is set as the reference photometric value. Thus, at the time of actual inspection, it is possible to inspect the chromaticity variation only by measuring the photometric value in the first wavelength region.

  In particular, a general pseudo white type LED often has a variation in chromaticity due to the spectral characteristics as shown in FIG. 3A. However, in certain types of LEDs, the G wavelength region and the R wavelength region are used. In some cases, the photometric values LG and LR are not significantly different. Therefore, in this case, only the photometric value LG in the G wavelength region is measured in advance, and only the photometric value LB in the B wavelength region is measured at the time of inspection, so that the chromaticity variation inspection to which the present invention is applied can be performed. realizable. Therefore, when performing an inspection in such a form, the photometric unit of the inspection apparatus can be configured by only the B sensor, and the configuration can be further simplified.

  In the embodiment, the relative ratio between the B photometric value and the G photometric value is used as the chromaticity value in each LED. However, in some cases, the relative difference between the B photometric value and the G photometric value is calculated and used as the chromaticity value. Also good. Alternatively, in view of the logarithmic difference in chromaticity felt with the naked eye, the logarithmic value (log value) of the relative ratio between the B photometric value and the G photometric value may be used as the chromaticity value. About these, it can set suitably according to the light emission characteristic of LED used as test | inspection object.

  In the embodiment, the relative value with respect to the average value of each chromaticity value is used as the relative value with respect to the average value when determining the chromaticity variation in the second inspection, but a deviation value may be used. In this case, a standard deviation is obtained from a plurality of chromaticity values and an average value thereof, a deviation value of each chromaticity value with respect to the standard deviation is obtained, and chromaticity variation is determined based on the deviation value. Good.

  In the embodiment, the example in which the chromaticity inspection apparatus for inspecting the chromaticity variation of the fog lamp using four LEDs as light sources has been described. However, the embodiment is not limited to the number of light sources, that is, the number of LEDs. The present invention can also be applied as an inspection apparatus for inspecting chromaticity variations in lamps other than the above, such as headlamps and clearance lamps. Furthermore, the present invention can also be applied as a chromaticity variation inspection device in a light emitting device other than a vehicle lamp, for example, a backlight illumination device of a display device or a light emitting device using a light emitting element other than an LED as a light source.

CT chromaticity inspection device FL fog lamp (light emitting device)
Aa to Ad Light-emitting area SB, SG Light sensor Lb, LG Photometric value (first photometric value, second photometric value)
CV (CVa to CVd) Chromaticity value Dx Chromaticity difference Dr Reference value Da to Dd Relative value (relative difference)
M Average value REF1 Reference relative value range (first range)
REF2 standard average value range (second range)
1a to 1d Light emitting diode (LED)
3a to 3d LED module 100 arithmetic unit 101 (101a to 101d) chromaticity value arithmetic unit 102 average value arithmetic unit 103 relative value arithmetic unit 104 storage units 110, 110A, 110B photometric unit 111 light transmissive diffuser 112 optical sensor pair 120 determination Part

Claims (6)

An inspection apparatus for inspecting the chromaticity of emission color of a light-emitting device comprising a plurality of light sources, each light source and the light-emitting element that emits blue light, a phosphor that said excited by blue light to emit yellow light includes, Ri configuration der which a mixture of the yellow light and the blue light to emit pseudo white light, and the blue light region of the first wavelength region, respectively metering the respective intensity of the green light region of the second wavelength region Means for detecting the first photometric value and the second photometric value; chromaticity value calculating means for calculating the chromaticity value of each light source from the first photometric value and the second photometric value; and A chromaticity inspection apparatus comprising: a relative value calculation unit that calculates a relative value of each chromaticity value; and a determination unit that determines suitability of chromaticity of the emission color based on the relative value.   The means for detecting the first photometric value and the second photometric value are respectively disposed in a light transmission diffuser plate on which the light of each light source is projected, and a plurality of regions on which the light of each light source is projected, The chromaticity inspection apparatus according to claim 1, further comprising: an optical sensor pair that receives each light in the first wavelength region and the second wavelength region transmitted through the light transmission diffusion plate.   The means for detecting the first photometric value and the second photometric value includes a light transmissive diffusion plate on which the light of each light source is projected, and light in a plurality of regions of each of the light sources transmitted through the light transmissive diffuser plate. The chromaticity inspection apparatus according to claim 1, further comprising an image pickup apparatus having a color image pickup device that picks up images collectively. The relative value calculating means is a means for calculating a difference between a maximum value and a minimum value of chromaticity values of the respective light sources, and the determining means determines that chromaticity is appropriate when the difference is equal to or less than a predetermined value. The chromaticity inspection apparatus according to any one of claims 1 to 3 , further comprising: The relative value calculating means is a means for calculating an average value of chromaticity values of the respective light sources, and further calculating a relative value of each chromaticity value with respect to the average value, and the determining means is that each relative value of each of the light sources is calculated. The color according to any one of claims 1 to 3 , further comprising means for determining that chromaticity is appropriate when the average value is within a predetermined first range and the average value is within the predetermined second range. Degree inspection device. An inspection method for inspecting the chromaticity of emission color of a light-emitting device comprising a plurality of light sources, each light source and the light-emitting element that emits blue light, a phosphor that said excited by blue light to emit yellow light includes, Ri configuration der which a mixture of the yellow light and the blue light to emit pseudo white light, and the blue light region of the first wavelength region, respectively metering the respective intensity of the green light region of the second wavelength region Detecting a first photometric value and a second photometric value, calculating a chromaticity value of each light source from the first photometric value and the second photometric value, and calculating a chromaticity value of each light source. A chromaticity inspection method comprising a step of calculating a relative value and a step of determining suitability of chromaticity of the emission color based on the relative value.

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