JP2010071807A - Photometric method for light source bulb for vehicle lighting fixture and light emitting property model generation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a photometric method for a light source bulb capable of contributing improvement of the accuracy of optical simulation of a vehicle lighting fixture by a simple technique. <P>SOLUTION: A light source bulb 2 having a specular surface formed by covering a surface of a base on a glass bulb side with a reflection member is disposed on a rotation support base 1 and lit, and a light receiver 3 is disposed to be movable around the light source bulb 2. The rotation support base 1 is rotated at a predetermined angle pitch every time when the light receiver 3 is moved with respect to a center axis Xc of the light source bulb 2 at the predetermined angle pitch. The brightness is measured after every movement. Since the obtained brightness data include that of direct light from the light source bulb and that of reflection light from the specular surface, brightness data of the reflection light is regarded as that of direct light from the light source bulb to the specular surface, and three-dimensional brightness distribution data of the direct light from the light source bulb is determined. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a light metering method and a light emission characteristic model generation method for a light source bulb for a vehicle lamp, and more specifically, measurement data collection and data processing for constructing a light source data file used for optical simulation of a vehicle lamp The present invention relates to a photometric method and a light emission characteristic model generation method for a light source bulb for a vehicle lamp according to the above.

  In general, in the design / development stage, vehicular lamps are advanced while verifying the ideal shape of reflectors and lenses that make up the optical system and their ideal positional relationship including the light source using optical simulation. Is.

  In that case, the light source is often appropriately selected from those already standardized, and is rarely newly developed along with the design and development of the vehicular lamp.

  Therefore, when designing and developing a vehicular lamp, a data file (light source data file) for optical simulation related to the light source is constructed in advance by direct optical measurement of the selected light source, and the basis for optical simulation of the vehicular lamp. Utilizing it as data can improve the accuracy of optical simulation.

  As a specific conventional measurement method, a measurement method using a light distribution characteristic measurement device as described below has been proposed. That is, a light source sample is sequentially placed on a horizontal substrate via a rotary stage, a three-dimensional adjustment mechanism, and a sample stage, and the light source sample is set to rotate 360 ° about the Z axis perpendicular to the horizontal substrate.

  At the same time, a light receiver is sequentially mounted on the horizontal substrate through the standing plate portion, the rotation shaft, and the rotation plate, and the angle of the light receiver to the Z-axis direction with the Z-axis direction perpendicular to the horizontal substrate being 0 ° is determined. Install so that it rotates more than ± 90 °.

  In the measurement, first, the light receiver is aligned so that the light receiving axis of the light receiver coincides with the optical axis (Z axis) of the light source sample, and the light intensity at that position is measured. Next, the light intensity is measured at each predetermined angle θ while the light receiver is inclined by a predetermined angle δ from the Z axis and the light source sample is rotated 360 °.

Then, each time the light receiver is sequentially set to a predetermined angle δ with respect to the Z axis, the light intensity is measured for each predetermined angle θ while rotating the light source sample by 360 °, and at least the angle δ of the light receiver with respect to the Z axis is Repeat measurement until 110 °. Thus, the light intensity is represented by a function based on the coordinate parameters (δ, θ) at a distance R in the predetermined radial direction from the center (see, for example, Patent Document 1).
JP 2008-70290 A

  When the light source sample is a vehicle lamp light source bulb (hereinafter abbreviated as a light source bulb), as shown in FIG. 13, an annular base 51 extending in the radial direction of the glass bulb 50 is formed at the bottom of the glass bulb 50. There is something with.

  When the light intensity of this type of light source bulb 52 is measured by the above method, if the angle δ of the light receiver with respect to the central axis Xb is greater than δmax when the direction of the central axis Xb of the light source bulb 52 is 0 °, the light source bulb 52 The light emitted from the light emission source 53 is shielded by the base 51 and does not reach the light receiver, making it impossible to collect light intensity data. That is, the light distribution characteristic measuring device cannot measure the light emitted from the light source 53 of the light source bulb 52 toward the base 51.

  When the light source bulb 52 is mounted on a vehicle lamp, the portion of the base 51 is covered with a reflector, and light emitted from the light source 53 of the light source bulb 52 toward the base 51 is a region of the reflector that covers the base 51. Is reflected in the irradiation direction of the vehicular lamp and is irradiated forward as part of the irradiation light.

  When the vehicle lamp having such a configuration is subjected to an optical simulation using a light source data file constructed based on the light intensity data obtained by the light distribution characteristic measuring device, the light source data file includes a light source bulb 52 to a base 51. The light intensity data of the light emitted toward is not captured, and the accuracy of the optical simulation is low.

  Therefore, the present invention was devised in view of the above problems, and the object of the present invention is to provide a photometric method and light emission characteristics of a light source bulb that can contribute to improving the accuracy of optical simulation of a vehicular lamp by a simple method. To provide a model generation method.

In order to solve the above-mentioned problems, the invention described in claim 1 of the present invention has a light emitting source in an airtight space by a glass bulb, and a base extending in the radial direction of the glass bulb at the bottom of the glass bulb. A photometric method of a light source bulb for a vehicle lamp provided,
The direction of the light receiving element mounted on the measuring instrument is always photometrically measured for each of the light source bulb in which the glass bulb side surface of the base is covered with a reflecting member to provide a specular reflection surface and the light source bulb in which the specular reflection surface is not provided. The light source bulb to be measured is measured in a three-dimensional direction by the measuring instrument in a state where the distance between the light receiving element and the light source is always constant, and the light source bulb is measured on a three-dimensional coordinate. Obtaining a ray vector value and a luminance value for each of a plurality of regions;
Reflection from photometric data including direct light and reflected light reflected from the specular reflection surface and from photometry data including only direct light, obtained from the light source bulb provided with the specular reflection surface and the light source bulb not provided with the specular reflection surface. Extracting light metering data; and
Extracting the photometric data of the reflected light as light emitted from the light source bulb in the direction of the specular reflection surface.

  In the invention described in claim 2 of the present invention, in claim 1, the photometric range in the three-dimensional direction measured by the measuring device is at least a central axis passing through the light emitting source of the light source bulb. The circumferential direction as the center is the entire circumference, and the inclination direction with the central axis as the center is from the central axis until the light receiving axis passing through the light receiving element of the measuring instrument reaches the outer edge of the specular reflection surface. It is characterized by doing.

  According to a third aspect of the present invention, in any one of the first or second aspect, the light receiving element is a CCD.

  Moreover, the invention described in claim 4 of the present invention is the light emitted from the light source bulb obtained by the photometric method according to claims 1 to 3 to the specular reflection surface and the light from the light source bulb. The light-emitting characteristic model of the light source bulb is generated by combining the photometric data with the direct light.

  The present invention is a photometric method for obtaining actual measurement data of a light source bulb for constructing a light source data file used for optical simulation of a vehicular lamp, and in particular, in photometry of a light source bulb having a base that obstructs photometry. The desired photometric data can be obtained without being affected by the presence of the base.

  Therefore, the glass bulb side surface of the base is covered with a reflecting member to be a specular reflection surface, the direction of the light receiving element mounted on the measuring instrument is always directed to the light source of the light source bulb, and the light receiving element and the light source The light source bulb is photometrically measured from the three-dimensional direction by the measuring instrument in a state in which the distance is always constant, and among the obtained photometric data, photometric data based on reflected light is emitted from the light source bulb toward the specular reflection surface. Captured as direct light.

  As a result, it is possible to obtain desired photometric data without being affected by the presence of the base by simply performing a simple process such as providing a specular reflection surface on the base that interferes with photometry during light metering of the light source bulb. became.

  Hereinafter, a preferred embodiment of the present invention will be described in detail with reference to FIGS. 1 to 12 (the same reference numerals are given to the same portions). The embodiments described below are preferable specific examples of the present invention, and thus various technically preferable limitations are given. However, the scope of the present invention particularly limits the present invention in the following description. Unless stated to the effect, the present invention is not limited to these embodiments.

  FIG. 1 is an explanatory diagram of a photometric device according to a photometric method of a light source bulb for a vehicle lamp of the present invention, FIG. 2 is an explanatory diagram of a light source bulb of an object to be measured, FIG. 3 is an explanatory diagram of a photometric method according to the present invention, FIG. FIG. 5 is an explanatory diagram of a photometric method according to the present invention, FIG. 5 is an explanatory diagram showing a luminance photograph and a group of luminance photos, FIG. 6 is an explanatory diagram showing the principle of photometry, and FIG. 7 is light source data constructed by a conventional photometric method. FIG. 8 is an explanatory diagram of a light source bulb that is an object to be measured by a conventional photometric method, FIG. 9 is a two-dimensional image of a light source data file constructed by the photometric method of the present invention, and FIG. 10 is a photometric direction. FIG. 11 is an explanatory view of another light source bulb, and FIG. 12 is an explanatory view showing a state in which a reflecting member is attached to the light source bulb of FIG.

  As shown in FIG. 1, the light source bulb 2 to be measured is placed on the rotation support base 1 so that the center axis Xa of the rotation support base 1 and the center axis Xb of the light source bulb 2 are located on the same straight line.

  The light receiver (measuring device) 3 includes a CCD (two-dimensional CCD) (not shown) composed of a plurality of vertical and horizontal pixels as light receiving elements on the light receiving axis Xc. 3 from the position where the light receiving axis Xc of the light source bulb 2 is on the same straight line as the central axis Xb of the light source bulb 2 and the central axis Xa of the rotary support base 1 in the tilt direction with the position of the measurement origin (light emitting source) P of the light source bulb 2 as the center. They are arranged so as to move in the same plane.

  Therefore, the light receiving element always faces the direction of the light emitting source, and the distance between the light receiving element and the light emitting source is always constant.

  As shown in FIG. 2, the light source bulb 2 placed on the rotary support 1 has a shape including an annular base 5 extending in the radial direction of the glass bulb 4 at the bottom of the glass bulb 4. Yes. In photometry, the entire surface of the base 5 on the glass bulb 4 side is covered with a reflecting member 6, and the surface is used as a specular reflecting surface 7.

  The thickness of the reflecting member 6 is formed as thin as possible so as not to impair the original shape of the light source bulb 2 so as not to reduce the photometric accuracy.

  Next, a photometric method will be described with reference to FIG. First, a rated voltage (current) is applied to the light source bulb 2 placed on the rotation support base 1 from an external power source to light it, and a state in which a luminous flux equivalent to that in practical use is emitted from the light emitting source is maintained.

  Then, the light receiver 3 is set so that the light receiving axis Xc of the light receiver 3 is located on the same straight line as the central axis Xb of the light source bulb 2 and the central axis Xa of the rotation support base 1, and the light receiving element (CCD) The luminance distribution of the light source bulb 2 is measured by each pixel. This luminance distribution is like a photographic image obtained by photographing the luminance distribution on the surface of the glass bulb 4 of the light source bulb 2 with a CCD. Therefore, it is hereinafter referred to as a luminance photograph.

Next, the light receiver 3 is moved, and the angle α that the light receiving axis Xc of the light receiver 3 makes with the central axis Xb direction of the light source bulb 2 as 0 ° is a predetermined angle α ₁ (for example, Set to a position where α = 1 °. Thereafter, the rotation support 1 is rotated 360 ° from the reference position in the θ direction at a predetermined angle β ₁ (for example, β ₁ = 1 °), and the luminance distribution is measured by the CCD at each angle β ₁ to obtain a luminance photograph. create.

Then, sequentially light receiver 3, and moves at an angle alpha ₁ intervals in the direction (inclination direction) away light receiving axis Xc from the center axis Xb direction of the light source valve 2 of the light receiving unit 3, in each case, relative to the rotating support base 1 The position is rotated 360 ° in the θ direction at a predetermined angle β ₁ from the position, and the luminance distribution is measured by the CCD for each angle β ₁ to create a luminance photograph.

  This photometric process is a region from the position where the light receiving axis Xc of the light receiver 3 is collinear with the central axis Xb of the light source bulb 2 and the central axis Xa of the rotation support base 1 to immediately before being blocked by the base 5 of the light source bulb 2. That is, as shown in FIG. 4, the angle α formed from the position where the light receiving axis Xc of the light receiver 3 is collinear with the central axis Xb of the light source bulb 2 with the central axis Xb direction being 0 ° and the central axis Xb direction. Is performed in a region until αmax reaches αmax.

  When the angle α is greater than or equal to αmax, the light emitted from the light source bulb 2 is shielded by the base 5 and does not reach the light receiver 3, and direct light as in the photometric method using the conventional light distribution characteristic measuring apparatus described above. Measurement of is impossible.

  Therefore, in the photometric method of the present invention, the entire surface of the base 5 of the light source bulb 2 on the glass bulb 4 side is covered with the reflecting member 6 so that the surface is the specular reflection surface 7, and the light is emitted from the light source bulb 2 toward the base 5. The reflected light is reflected by the mirror reflecting surface 7 of the reflecting member 6 and taken into the CCD as reflected light. The direct light emitted from the light source bulb 2 and the reflected light emitted from the light source bulb 2 and reflected by the mirror reflecting surface 7 are reflected. To form a luminance photograph.

  As a result, as shown in FIG. 5, a luminance photograph group 10 by a plurality of luminance photographs 9 arranged in a spherical shape around the position of the light source (for example, filament) 8 of the light source bulb 2 so as to surround the light source bulb 2. Is generated.

  Next, a procedure for creating a light source data file based on the luminance photograph group obtained by photometry of the light source bulb 2 will be described below.

  First, a three-dimensional shape model of the light source bulb 2 used for photometry is created on CAD. This three-dimensional shape model also incorporates a specular reflection surface 7 of the reflection member 6 that covers the base 5.

  The three-dimensional shape model of the light source bulb 2 and the luminance photograph group are maintained in the positional relationship at the time of photometry, and the measurement origin (light emission source) of the light source bulb 2 is set as the coordinate origin O (0, 0, 0) 3 The individual luminance photographs constituting the luminance photograph group, which are arranged in a three-dimensional coordinate space, are divided into a plurality of predetermined regions, and ray tracing is performed in the direction of the three-dimensional shape model of the light source bulb 2 using each divided minute region as a base point. I do.

  Then, in the minute region of the luminance photograph, there can be one in which the arrival point of ray tracing based on the minute region becomes the glass bulb of the light source bulb, and one that becomes the specular reflection surface.

  When the reaching point of ray tracing based on each minute region is a glass bulb, each of the three-dimensional ray vector V (x, y, z) and the luminance value L at each ray tracing reaching point of the glass bulb is used. Information is calculated based on the photometric luminance value of each base point and the direction of the ray trajectory from the base point to the position Q (x, y, z) of the glass bulb.

  On the other hand, when the arrival point of ray tracing with each minute region as a base point becomes a specular reflection surface, as shown in FIG. 6, the glass bulb in which the light rays M reflected at the position of the ray tracing arrival point on the specular reflection surface 7 intersect. 4 position Q (x, y, z) is obtained, and the luminance value L of the position Q is calculated based on the photometric luminance value of each base point. At this time, as the photometric luminance value at the base point, a value in consideration of the luminance attenuation due to the reflection of the specular reflection surface is used so as not to impair the calculation accuracy of the luminance value L.

  The ray vector V (x, y, z) at this time connects the position of the ray tracing arrival point on the specular reflection surface and the position Q (x, y, z) of the glass bulb where the ray reflected by the specular reflection surface intersects. It is obtained by calculating the direction of the ray trajectory.

  That is, the luminance data by the reflected light reflected by the specular reflection surface is regarded as the direct light from the light source bulb toward the specular reflection surface.

  In this way, each information of the light vector V (x, y, z) and the luminance value L at the three-dimensional position Q (x, y, z) of the light source bulb that emits the light toward the base of the light source bulb is the base. It is calculated | required by utilizing the photometry data of the reflected light by the specular reflection surface 7 of the reflection member 6 which covers the surface.

  That is, by measuring the direct light emitted from the light source bulb 2 and the reflected light emitted from the light source bulb 2 and reflected by the specular reflection surface 7, a three-dimensional position Q (over the entire surface of the glass bulb of the light source bulb ( It is possible to construct an information data file (light source data file) related to the light vector V (x, y, z) and the luminance value L in x, y, z).

  FIG. 7 shows a two-dimensional image of a light source data file constructed based on data obtained by directly measuring the conventional light source bulb having the shape shown in FIG. 8, and FIG. 9 shows a light source having the shape shown in FIG. FIG. 3 shows a two-dimensional image of a light source data file constructed on the basis of data obtained by photometric measurement of the light source bulb 2 shown in FIG. 2 in which the base of the bulb is covered with a reflecting member and the surface is a specular reflection surface.

  7 and 9, the UD (90 ° -90 °) direction of the vertical axis is the UD direction (direction perpendicular to the winding direction of the filament serving as the light emitting source 8) shown in FIG. Correspondingly, the direction of LR (180 ° -180 °) on the horizontal axis also corresponds to the LR direction (direction parallel to the winding direction of the filament serving as the light emitting source 8) shown in FIG. In addition, a pair of water droplet-like regions E having a luminous intensity of 0 located on the LR line whose UD direction is 0 ° is a shadow portion projected by an introduction line that supports a light emission source (filament). A pair of semi-circular light intensity areas F are projected shadow portions of the base part.

  When FIG. 7 is compared with FIG. 9, the area F having a light intensity of 0 by the base in FIG. 9 is much smaller than the area F having a light intensity of 0 by the base in FIG. 7. That is, it has been verified that the light metering method of the present invention can construct the light source data file of the light source bulb over a wide range by reducing the influence of the base compared with the conventional metering method.

  Note that some light source bulbs with caps have other shapes, for example, some have a flat plate-like fusion sealing portion 11 at the bottom of the glass bulb 4, as shown in FIG. In this case, as shown in FIG. 2 described above, when photometry is performed with the entire surface of the base on the glass bulb side covered with a reflecting member and the surface as a specular reflecting surface, the light receiver is positioned on the substantially central axis of the light source bulb. Sometimes, the direct light from the light source overlaps the optical path of the reflected light that is emitted from the light source directly below the glass bulb, reflected by the specular reflection surface, and guided again through the glass bulb, and is detected by the light receiver. It is difficult to separate the emitted light into direct light and reflected light.

  Therefore, in order to avoid such a problem, as shown in FIG. 12, the specular reflection surface 7 by the reflecting member 6 provided so as to cover the base is in a state where at least the portion directly below the glass bulb 4 is inclined with respect to the base. To place. In other words, the reflecting member 6 is provided so that the specular reflection surface 7 immediately below the glass bulb 4 is not perpendicular to the central axis Xb of the light source bulb 4.

  As a result, the direct light from the light source and the optical path of the reflected light that is emitted from the light source and reflected by the specular reflection surface do not overlap, and a light source data file that does not impair accuracy can be constructed.

  By the way, in order to improve the accuracy of the light source data file, when creating the light source data file from the luminance photograph data, the photometric brightness of the photometric luminance is taken into account in consideration of the distance between the glass bulb of the light source bulb and the light receiving element mounted on the receiver. It is also possible to use the distance correction parameter γ for the actually measured value.

  Specifically, the luminance value on the glass bulb in the light source data file = the measured value of photometric luminance by the light receiver × γ. The distance correction parameter γ is a distance correction parameter γ by actually measuring the luminance at a predetermined position on the glass bulb surface after the construction of the light source data file and comparing the measured luminance value with the luminance value in the light source data file at the same position of the glass bulb. Is adjusted so that the luminance value of the light source data file is close to the actually measured luminance value, and the distance correction parameter γ is optimized while repeating this processing, thereby improving the accuracy of the light source data file.

  The light source data file constructed in this way is the ideal shape of reflectors and lenses that make up the optical system together with the light source bulb, and their ideal positions including the light source at the design and development stage of the vehicular lamp. It is used as basic data for optical simulation to verify the relationship, and effectively contributes to the realization of optimized lamps.

  As described above, the photometric method of the light source bulb for vehicle lamps according to the present invention performs a simple process such as providing a specular reflection surface on the base that obstructs photometry at the time of photometry of the light source bulb. This has a great advantage that light emitted in the direction can be taken into a light receiver as reflected light by a specular reflection surface and used for construction of a light source data file.

It is explanatory drawing of the measurement photometry apparatus concerning this invention. It is explanatory drawing of the light source bulb of a to-be-measured object. It is explanatory drawing of the photometry method concerning this invention. Similarly, it is explanatory drawing of the photometry method concerning this invention. It is explanatory drawing of a brightness | luminance photograph. It is explanatory drawing which shows the photometry principle. It is a two-dimensional image of a light source data file constructed by a conventional photometric method. It is explanatory drawing of the light source bulb | ball used as the to-be-measured object of the conventional photometry method. It is a two-dimensional image of the light source data file constructed by the photometric method of the present invention. It is explanatory drawing which shows a photometry direction. It is explanatory drawing of another light source bulb. It is explanatory drawing which shows the state which attached the reflection member to the light source bulb of FIG. It is explanatory drawing explaining the conventional photometry method.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotation support stand 2 Light source bulb 3 Light receiver 4 Glass bulb 5 Base 6 Reflective member 7 Specular reflection surface 8 Light emission source 9 Luminance photograph 10 Luminance photograph group 11 Fusion sealing part

Claims (4)

A light metering method for a light source bulb for a vehicle lamp having a light emitting source in an airtight space by a glass bulb and having a base extending in a radial direction of the glass bulb at the bottom of the glass bulb,
The direction of the light receiving element mounted on the measuring instrument is always photometrically measured for each of the light source bulb in which the glass bulb side surface of the base is covered with a reflecting member to provide a specular reflection surface and the light source bulb in which the specular reflection surface is not provided. The light source bulb to be measured is measured in a three-dimensional direction by the measuring instrument in a state where the distance between the light receiving element and the light source is always constant, and the light source bulb is measured on a three-dimensional coordinate. Obtaining a ray vector value and a luminance value for each of a plurality of regions;
Reflection from photometric data including direct light and reflected light reflected from the specular reflection surface and from photometry data including only direct light, obtained from the light source bulb provided with the specular reflection surface and the light source bulb not provided with the specular reflection surface. Extracting light metering data; and
And a step of extracting the photometric data of the reflected light as light emitted from the light source bulb toward the specular reflection surface.   The photometric range in the three-dimensional direction that is measured by the measuring device is at least an entire circumference in the circumferential direction centered on the central axis that passes through the light emitting source of the light source bulb, and is inclined about the central axis. 2. The photometric method for a light source bulb for a vehicle lamp according to claim 1, wherein the direction is such that a light receiving axis passing through the light receiving element of the measuring instrument extends from the central axis to an outer edge of the specular reflection surface. .   The photometric method for a light source bulb for a vehicle lamp according to claim 1, wherein the light receiving element is a CCD.   The light source bulb is synthesized by combining the light emitted from the light source bulb obtained by the photometric method according to claim 1 to the specular reflection surface and the photometric data of the direct light from the light source bulb. A method for generating a light emission characteristic model of a light source bulb, comprising: generating a light emission characteristic model of the light source bulb.