JP6953657B2 - Calibration device and calibration method - Google Patents

Description

The present invention relates to, for example, a calibration device and a calibration method for calibrating a wellhead luminance meter that measures the brightness in a range including the wellhead of a tunnel.

Generally, tunnels are fitted with basic and entrance lights. The basic lighting is a lighting installed to ensure the brightness in the tunnel over the entire length of the tunnel. On the other hand, the entrance lighting is a lighting that adapts the driver's eyes when the driver enters the dark tunnel from the bright outdoors, and is installed near the tunnel entrance.

The output level of the illuminating light is controlled based on the output of the wellhead luminance meter installed at a position 150 m away from the wellhead of the tunnel. The wellhead luminance meter measures the average brightness over a wide range including the wellhead from the outside of the tunnel toward the tunnel (for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 07-294330

Wellhead luminance meters need to be calibrated on a regular basis to measure accurate luminance. However, conventional calibration work requires removing the wellhead luminance meter installed on site and sending it back to the equipment manufacturer. For this reason, there is a problem that a great deal of labor and time must be spent on calibration, such as removal and transportation of the wellhead luminance meter, and installation of an alternative machine.

In view of the above circumstances, an object of the present invention is to provide a calibration device and a calibration method capable of reducing the labor required for the calibration work of the wellhead luminance meter.

In order to achieve the above object, the calibration device for the luminance meter according to one embodiment of the present invention includes a calibration unit, a housing, and a control unit.
The calibration unit includes a light source, a reference luminance meter for measuring the brightness of the light source, and a support portion for supporting the light source and the reference luminance meter.
The housing has a light-shielding property, and is configured to accommodate the calibration unit and the luminance meter to be calibrated.
The control unit calibrates the luminance meter based on the output of the reference luminance meter and the luminance meter with reference to the measured value of the reference luminance meter.

According to this configuration, the calibration device calibrates the luminance meter in a light-shielding housing with the calibration unit and the luminance meter to be calibrated covered. As a result, the calibration work can be completed at the site where the luminance meter is installed.

Therefore, it is not necessary to remove the luminance meter installed in the field and send it back to the equipment manufacturer as in the conventional calibration work. Therefore, according to the present invention, it is possible to provide a calibration device capable of reducing the labor required for the calibration work of the luminance meter to be calibrated.

The housing may be configured to be connectable to the calibration unit.
As a result, as soon as the installation of the calibration device is completed, the calibration unit can be positioned with respect to the luminance meter to be calibrated. Therefore, the installation time for installing the calibration device on the luminance meter can be shortened.

The light source may be a surface light source facing the reference luminance meter and the luminance meter and having a light emitting surface orthogonal to the optical axis of the reference luminance meter and the luminance meter.

In order to achieve the above object, the calibration method of the luminance meter according to one embodiment of the present technology includes a light source, a reference luminance meter for measuring the brightness of the light source, and a support portion for supporting the light source and the luminance meter. The calibration unit having the above and the luminance meter to be calibrated are housed in a light-shielding housing.
The brightness of the light source is measured.
The luminance meter is calibrated based on the measured value of the reference luminance meter.

In the step of accommodating the calibration unit and the luminance meter in the housing, the luminance meter is connected to the calibration unit so that the light emitting surface of the light source is orthogonal to the optical axis of the luminance meter. It may be housed in a housing.

As described above, according to the present invention, it is possible to provide a calibration device and a calibration method capable of reducing the labor required for the calibration work of the wellhead luminance meter.

It is a schematic diagram which shows the state which the well-headed luminance meter to which the calibration apparatus of this invention is applied measures the brightness in the visual field range including the wellhead of a tunnel. It is a schematic diagram which shows the structural example of the said calibration apparatus. It is a top view of the calibration apparatus. It is a flowchart which shows the structure method of the said calibration apparatus. It is a schematic diagram which shows the state of installing the said calibration apparatus. It is a schematic diagram which shows the structural example of the calibration apparatus which concerns on 2nd Embodiment of this invention. It is a flowchart which shows the calibration method of the wellhead luminance meter in the said embodiment. It is a schematic diagram which shows the structural example of the calibration apparatus which concerns on the modification of this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the present embodiment, for example, a calibration device and a calibration method for a wellhead luminance meter for measuring the brightness in a range including the tunnel entrance will be described.

<First Embodiment>
FIG. 1 is a schematic view showing a state in which the wellhead luminance meter L to which the calibration device 1 according to the present embodiment is applied measures the luminance in the visual field range E including the wellhead M of the tunnel T.

The wellhead luminance meter L is a luminance meter to be calibrated by the calibration device 1, and corresponds to a "luminance meter" in the claims. As shown in FIG. 1, the wellhead luminance meter L is installed at a position 150 m away from the wellhead M of the tunnel T. The wellhead luminance meter L measures and measures the average brightness within a range E of a circular viewing angle of 20 ° centered on the center of the wellhead M when the wellhead M of the tunnel T is viewed from a position 150 m away from the wellhead M. The result is output to the tunnel lighting controller C.

The wellhead luminance meter L of the present embodiment converts the luminance value in the visual field range E into a luminance value according to the luminance conversion table in which the preset luminance value and the luminance value are associated with each other, and tunnels the luminance value. Output to the lighting controller C. The gradation step of the shade value measured by the wellhead luminance meter L is, for example, 12 bits (4096 steps).

The tunnel lighting controller C is electrically or wiredly connected to the entrance lighting L1 and the wellhead luminance meter L, which will be described later. The tunnel illumination controller C is configured to be able to control the entrance illumination lamp L1 to the optimum brightness based on the output result of the wellhead luminance meter L.

In the tunnel T of the present embodiment, the entrance lighting L1 and the basic lighting L2 are installed on the inner wall thereof. As shown in FIG. 1, a plurality of entrance lighting lights L1 are installed between the basic lighting lights L2 in the vicinity of the wellhead M of the tunnel T. The entrance lighting L1 has a function of acclimatizing the eyes of a driver who has entered a dark tunnel T from a bright outdoor environment.

A plurality of basic lighting lights L2 are installed at predetermined intervals over the entire length of the tunnel T to illuminate the inside of the tunnel T. The number and layout of the basic lighting L2 and the entrance lighting L1 are not limited to those shown in FIG. 1, and a larger number of the basic lighting L2 and the entrance lighting L1 are actually installed in the tunnel T.

[Calibration device configuration]
FIG. 2 is a schematic view showing a configuration example of the calibration device 1 according to the present embodiment. In the following figures, the X, Y, and Z-axis directions indicate three axial directions that are orthogonal to each other.

The calibration device 1 according to the present embodiment is a calibration device that calibrates the wellhead luminance meter L, and accommodates the wellhead luminance meter L from the Z-axis direction. As shown in FIG. 2, the calibration device 1 includes a calibration unit 100, a housing 40, and a control unit 50. The configuration of the calibration device 1 is not limited to the following description.

(Calibration unit)
As shown in FIG. 2, the calibration unit 100 includes a light source 10, a reference luminance meter 20, and a support portion 30. The light source 10 is a surface light source configured to be capable of emitting illumination light in the X-axis direction. The light source 10 has a light emitting surface 10a that faces the reference luminance meter 20 and the wellhead luminance meter L in the X-axis direction and is orthogonal to the optical axis of the reference luminance meter 20 and the wellhead luminance meter L.

Light source 10, for example, the output configured to be able to illumination light 10 cd / ^{m 2} over 1 million cd / ^{m 2} or less of luminance. The color of the illumination light emitted by the light source 10 is not particularly limited, but is typically white.

The light source 10 of the present embodiment can be an array-shaped light source composed of a plurality of LED (Light Emitting Diode) light sources. In this case, the type of LED light source constituting this array-shaped light source is not particularly limited, and for example, a cannonball type, a surface mount type (SMD), a COB type, or the like may be adopted.

The reference luminance meter 20 is installed at a position separated from the light source 10 in the X-axis direction by a predetermined distance, and is supported by one end of the support portion 30 (first plate portion 30a). The reference luminance meter 20 is configured to be capable of measuring the luminance of the illumination light emitted from the light emitting surface 10a.

Measurement range of the luminance of the reference luminance meter 20 is, for example, 10 cd / ^{m 2} over 1 million cd / ^{m 2} or less, measured as a true value in order to calibrate the wellhead luminance meter L (luminance value) the controller 50 It is configured to be able to output to.

As shown in FIG. 2, the support portion 30 is composed of a first plate portion 30a and a second plate portion 30b. The first plate portion 30a takes a longitudinal direction in the Y-axis direction and supports the light source 10. The second plate portion 30b has a longitudinal direction in the X-axis direction, one end is connected to the first plate portion 30a, and the other end supports the reference luminance meter 20.

The support portion 30 is not limited to the L-shaped plate-shaped member composed of the first and second plate portions 30a and 30b, and the calibration device 1 is provided as long as it can support the light source 10 and the reference luminance meter 20. It may be changed as appropriate according to the specifications and applications of.

(Case)
FIG. 3 is a plan view of the calibration device 1 as viewed from the Z-axis direction. Note that the control unit 50 is not shown in FIG. As shown in FIG. 3, the housing 40 is a box-shaped container that houses the calibration unit 100 and the wellhead luminance meter L. The housing 40 of the present embodiment is configured to be connectable to the calibration unit 100 or the light source 10 via a connecting portion (not shown).

As shown in FIG. 3, the housing 40 has a storage space 41 facing the light source 10 in the X-axis direction and facing the reference luminance meter 20 in the Y-axis direction. The wellhead luminance meter L of the present embodiment is accommodated in the accommodation space 41 included in the housing 40.

The inner or outer surface of the housing 40 is coated with, for example, a metal material, or the outer surface is coated with a light-shielding molded product, or the housing 40 is formed of the light-shielding material itself to allow light from the outside world to be emitted. It has the property of blocking light.

The metal material preferably reflects a large amount of light, and examples thereof include aluminum, silver, titanium, and chromium. However, it is desirable that the inner surface of the housing 40 is coated with a matte black coating in order to suppress the influence of stray light.

As the light-shielding molded product, for example, a light-shielding synthetic resin or the like is adopted. The light-shielding synthetic resin is a mixture in which a synthetic resin such as polystyrene, polyvinyl chloride or polycarbonate is used as a base, and a white paint such as titanium oxide or alumina, carbon black, or the metal materials listed above are blended therein. Etc. are adopted.

As the light-shielding material, for example, similarly to the light-shielding molded product, a synthetic resin such as polystyrene, polyvinyl chloride or polycarbonate is used as a base, and a white paint such as titanium oxide or alumina, carbon black, or carbon black, or listed above. A mixture or the like containing a metal material is adopted.

(Control unit)
The control unit 50 is arranged outside the calibration unit 100 and the housing 40, and is electrically or wiredly connected to the light source 10, the reference luminance meter 20, and the wellhead luminance meter L. The control unit 50 calibrates the wellhead luminance meter L based on the outputs of the reference luminance meter 20 and the wellhead luminance meter L with reference to the measured value of the reference luminance meter 20.

The control unit 50 has hardware necessary for a computer such as a CPU (Central Processing Unit), a ROM (Read Only Memory), a RAM (Random Access Memory), and an HDD (Hard Disk Drive). The CPU controls the operations of the light source 10, the reference luminance meter 20, and the wellhead luminance meter L by loading and executing the program stored in the ROM or HDD in the RAM.

The program is installed in the control unit 50 via, for example, various storage media (internal memory). Alternatively, the program may be installed via the Internet or the like. In the present embodiment, for example, a laptop PC (Personal Computer), a tablet terminal, or the like is used as the control unit 50, but any other computer may be used.

[Calibration method]
FIG. 4 is a flowchart showing a method in which the calibration device 1 calibrates the wellhead luminance meter L. Hereinafter, the calibration method of the calibration device 1 will be described with reference to FIG. 4 as appropriate.

(Step S01: Installation of calibration device)
In step S01, the calibration unit 100 and the wellhead luminance meter L are housed in the light-shielding housing 40.

FIG. 5 is a schematic view showing how the calibration device 1 is installed. Note that the control unit 50 is not shown in FIG.

First, the housing 40 to which the calibration unit 100 is connected is placed on the mounting plate B attached to the wellhead luminance meter L. At this time, the plurality of mounting holes H1 provided in the housing 40 and the plurality of through holes H2 formed in the mounting plate B face each other in the Z-axis direction. As a result, the wellhead luminance meter L is accommodated in the accommodation space 41 of the housing, and the light emitting surface 10a is orthogonal to the optical axis of the wellhead luminance meter L.

Next, a screw S, a bolt, or the like that penetrates the through hole H2 is screwed into the mounting hole H1. As a result, the housing 40 is fixed to the mounting plate B, and the calibration unit 100 is positioned with respect to the wellhead luminance meter L.

In the present embodiment, by adopting the installation method as described above, the calibration unit 100 is positioned with respect to the wellhead luminance meter L at the same time when the installation of the calibration device 1 is completed. As a result, the installation time for installing the calibration device 1 on the wellhead luminance meter L can be shortened.

In step S01, the method is not limited to the method of accommodating the wellhead luminance meter L in the housing 40 connected to the calibration unit 100 in advance. For example, after positioning the calibration unit 100 with respect to the wellhead luminance meter L, the calibration unit The 100 and the wellhead luminance meter L may be housed in the housing 40.

(Step S02: Luminance measurement)
In step S02, the reference luminance meter 20 measures the brightness of the illumination light emitted from the light source 10, and the wellhead luminance meter L measures the shade value of the illumination light emitted from the light source 10.

First, the light source 10 irradiates the illumination light in multiple stages while raising the output level from the low level to the limit value. The reference luminance meter 20 and the wellhead luminance meter L receive the illumination light. Here, the reference luminance meter 20 measures the luminance values corresponding to each output level of the light source 10, and outputs these luminance values to the control unit 50. On the other hand, the front luminance meter L measures the shading values according to the output level of the light source 10, and outputs these shading values to the control unit 50.

The control unit 50 determines the brightness value measured by the reference luminance meter 20 and the wellhead for each output level of the light source 10 based on the luminance value output from the reference luminance meter 20 and the shade value output from the wellhead luminance meter L. A first correspondence table is created in which the shade values measured by the luminance meter L are associated with each other.

Since the reference luminance meter 20 of the present embodiment is calibrated in advance so that the luminance value becomes a true value when measuring the luminance of the light source 10, the first corresponding table is the output of the light source 10. For each level, the shade value measured by the wellhead luminance meter L and the true luminance value are associated with each other.

(Step S03: Calibration of wellhead luminance meter)
In step S03, the control unit 50 calibrates the wellhead luminance meter L with reference to the measured value of the reference luminance meter 20. Specifically, the wellhead luminance meter L is calibrated by applying the first corresponding table created in the previous step S02 to the wellhead luminance meter L.

More specifically, in the first correspondence table, when the luminance value corresponding to the shade value for each output level of the light source 10 deviates from the true luminance value, the control unit 50 is output from the reference luminance meter 20. Correct based on the brightness value. That is, the brightness value corresponding to the shade value for each output level of the light source 10 in the first correspondence table is corrected so that the control unit 50 becomes the true value brightness value output from the reference luminance meter 20. As a result, the measured value of the wellhead luminance meter L is calibrated so as to be a true value.

[Action]
The calibration device 1 of the present embodiment is configured to be able to calibrate the wellhead luminance meter L in a state where the calibration unit 100 and the wellhead luminance meter L are housed in the light-shielding housing 40. As a result, the calibration work can be completed at the site where the wellhead luminance meter L is installed.

That is, by applying the calibration device 1 of the present embodiment to the wellhead luminance meter L, it is not necessary to remove the wellhead luminance meter L installed in the field and send it back to the equipment manufacturer as in the conventional calibration work. Therefore, according to the present invention, it is possible to provide the calibration device 1 capable of reducing the labor required for the calibration work of the wellhead luminance meter L.

<Second embodiment>
FIG. 6 is a schematic view showing a configuration example of the calibration device 2 of the present embodiment. Hereinafter, the same configurations as those of the first embodiment are designated by the same reference numerals, and the description thereof will be omitted.

[Calibration device configuration]
As shown in FIG. 6, the calibration device 2 of the present embodiment is different from the first embodiment in that the reference luminance meter 20 and the support portion 30 are omitted. As a result, the number of parts in the calibration device 2 is reduced, and the handleability of the calibration device 2 is improved. Therefore, it is possible to improve the transportability and reduce the transport cost when transporting the calibration device 2 to the site where the wellhead luminance meter L is installed.

[Calibration method]
FIG. 7 is a flowchart showing a method of calibrating the wellhead luminance meter L in the present embodiment. In the calibration method of the wellhead luminance meter L of the present embodiment, after the light source 10 is calibrated so as to emit illumination light of known brightness in advance, only the light source 20 and the housing 40 are installed in the field where the wellhead luminance meter L is installed. It is to be carried to and calibrated. Hereinafter, the detailed calibration method will be described with reference to FIG. 7 as appropriate.

(Step S21: Light source calibration)
First, the light source 10 irradiates the illumination light in multiple stages while raising the output level from the low level to the limit value. At this time, the control unit 50 controls the current value flowing through the light source 20.

As a result, the light source 20 is calibrated so as to emit illumination light having a true brightness corresponding to each current value, and the control unit 50 associates the current value flowing through the light source 10 with the true brightness value. The second correspondence table is created.

In general, the light emission level of an LED fluctuates depending on the ambient temperature. Therefore, in step S21 of the present embodiment, the temperature of a predetermined portion of the LED is measured and recorded when the light source 10 is calibrated. Then, in step S24 described later, the temperature at the same location may be measured at the time of calibration of the wellhead luminance meter L, and the luminance may be corrected from the temperature difference.

Further, step S21 of the present embodiment may be executed in a state where the calibration unit 100 is housed in the housing 40, or may be executed in an environment where light from the outside world such as a dark room is blocked.

(Step S22: Installation of calibration device)
In step S22, the light source 10 and the wellhead luminance meter L are housed in the housing 40. At this time, typically, the wellhead luminance meter L is covered with the housing 40 connected to the light source 10 from the Z-axis direction so that the light emitting surface 10a is orthogonal to the optical axis of the wellhead luminance meter L.

In step S22, the method is not limited to the method of accommodating the wellhead luminance meter L in the housing 40 connected to the light source 10 in advance. For example, after positioning the light source 10 with respect to the wellhead luminance meter L, the light source 10 and the wellhead The luminance meter L may be housed in the housing 40.

(Step S23: Gradation value measurement)
In step S23, the wellhead luminance meter L measures the shade value of the illumination light emitted from the light source 10.

First, the control unit 50 controls the light source 10 so that the current value corresponding to the true luminance value flows to the light source 10 based on the second correspondence table, so that the light source 10 raises the output level from the low level to the limit value. Irradiate illumination light with true brightness over multiple stages. The wellhead luminance meter L receives the illumination light, measures the shading values according to the output level of the light source 10, and outputs these shading values to the control unit 50.

The control unit 50 has a third unit in which the shade value output from the wellhead luminance meter L and the brightness value corresponding to the shade value are associated with each other according to the above-mentioned brightness conversion table set in advance in the wellhead luminance meter L. Create a correspondence table.

(Step S24: Calibration of wellhead luminance meter)
In step S24, when the brightness value for each output level of the light source 10 in the third correspondence table deviates from the true brightness value, the control unit 50 sets the brightness value of the third correspondence table based on the second correspondence table. to correct.

That is, the control unit 50 compares the second corresponding table and the third corresponding table, and corrects the brightness value of the third corresponding table so that it becomes the brightness value of the second corresponding table. As a result, the measured value of the wellhead luminance meter L is calibrated so as to be a true value.

<Modification example>
Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and it goes without saying that various modifications can be made.

FIG. 8 is a schematic view showing a configuration example of the calibration device 1 according to the modified example of the present invention. The calibration device 1 of the above embodiment has a configuration in which the light emitting surface 10a of the light source 10 is orthogonal to the optical axes of the reference luminance meter 20 and the wellhead luminance meter L, but the present invention is not limited to this. For example, as shown in FIG. 8, the calibration device 1 may be configured such that the optical axes of the reference luminance meter 20 and the wellhead luminance meter L are inclined by a predetermined angle with respect to the direction orthogonal to the light emitting surface 10a.

Further, the calibration devices 1 and 2 of the above-described embodiment are configured to have a luminance meter for measuring the brightness of the light source 10, but the present invention is not limited to this, and for example, the luminous flux, luminous intensity, illuminance or luminous radiance of the light source 10 can be measured. It may be configured to have various measuring devices. Further, the reference luminance meter 20 of the above embodiment is not limited to a black-and-white camera, and may be, for example, a luminance sensor capable of measuring the luminance of the light source 10.

In addition, in the above embodiments, the calibration devices 1 and 2 are applied to, but not limited to, a wellhead luminance meter that measures the brightness in a range including the tunnel wellhead. The calibration devices 1 and 2 may be applied to any other luminance meter, and its use is not limited.

1, 2 ... Calibration device 10 ... Light source 10a ... Light emitting surface 20 ... Reference luminance meter 30 ... Support 40 ... Housing 41 ... Accommodation space 50 ... Control unit 100 ... Calibration unit L ... Wellhead luminance meter (luminance meter)

Claims (5)

A calibration unit having a light source, a reference luminance meter for measuring the brightness of the light source, and a support portion for supporting the light source and the reference luminance meter.
A light-shielding housing capable of accommodating the calibration unit and a luminance meter to be calibrated,
A luminance meter calibration device including a control unit for calibrating the luminance meter based on the reference luminance meter and the output of the luminance meter based on the measured value of the luminance meter. The calibrator of the luminance meter according to claim 1.
The housing is a calibration device for a luminance meter that is configured to be connectable to the calibration unit. The calibrator of the luminance meter according to claim 1 or 2.
The light source is a calibrator of a luminance meter, which is a surface light source facing the reference luminance meter and the luminance meter and having a light emitting surface orthogonal to the optical axis of the reference luminance meter and the luminance meter. A calibration unit having a light source, a reference luminance meter for measuring the brightness of the light source, a support portion for supporting the light source and the reference luminance meter, and a luminance meter to be calibrated are housed in a light-shielding housing. Process and
The process of measuring the brightness of the light source and
A method for calibrating a luminance meter, which comprises a step of calibrating the luminance meter with reference to a measured value of the reference luminance meter. The method for calibrating a luminance meter according to claim 4.
In the step of accommodating the calibration unit and the luminance meter in the housing, the luminance meter is connected to the calibration unit so that the light emitting surface of the light source is orthogonal to the optical axis of the luminance meter. How to calibrate the luminance meter housed in the housing.

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