JPH06273531A - Survey meter - Google Patents

Abstract

PURPOSE:To make it possible to easily, conveniently and highly accurately measure equivalent dose rate or the like with no individual difference or measurement error by providing means for measuring the distance from an object using laser light. CONSTITUTION:The survey meter 1 comprises a radiation measuring means 2, a distance measuring means 3, a display means 4, a laser power supply 10, and a grip 12. The distance measuring means 3 is a laser transmitting/receiving unit 6 comprising a sensor for emitting a visible laser light toward an object and receiving a reflected laser light, and a measuring circuit. A measuring person grips the meter 1 and directs the unit 6 toward the object. When a switch at a panel section 7 is turned on, laser light is emitted toward the object and the unit 6 measures the distance up to the object based on the time elapsed before reception of the laser light and displays the distance on the panel section 7. When power switch at a radiation measuring section 5 is turned on, an ionization chamber detects radiation from the object and then an equivalent dose rate is measured and displayed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a survey meter, and more specifically, to a dose equivalent rate required to be measured at a place where a distance and an angle from a measuring object are constant,
The present invention relates to a survey meter that can be easily and easily measured with high accuracy without individual differences or measurement errors.

[0002]

2. Description of the Related Art L-type, A
When transporting radioactive materials such as type B, type B, and IP type, from the viewpoint of preventing radioactive contamination and exposure, it is stipulated by law from the surface of packages, vehicles, ships, etc. that contain such radioactive materials. It is necessary to measure the dose equivalent rate at a position separated by a certain distance and evaluate whether the value complies with legal regulations. Conventionally, a portable survey meter that is easy to handle has been used to measure the dose equivalent rate.

However, the conventional survey meter is
Since there is no means to measure the distance from the measurement target, when the measurer uses this to measure the dose equivalent rate, the distance from the measurement target is manually measured beforehand with a tape measure and specified. I had to do it later. In such a case, since it is necessary to approach the measurement target, there is a risk of exposing the measurer to extra radiation. Since it is a manual work, it takes time to measure the distance. Further, there is a problem that the distance from the measurement object measured in this way is low in accuracy, and an error or the like is likely to occur in the value of the dose equivalent rate measured thereafter. In addition, when measuring on a transport vehicle or ship, the scaffolding at the measurement location is often poor, so it is not easy to maintain the angle between the radiation measurement part of the survey meter and the measured part of the measurement target at a right angle. However, there is a problem that an error or individual difference is likely to occur in the measured value.

Therefore, in order to solve such a problem, a survey meter having an antenna-shaped telescopic bar with a maximum extension of 1 m has been proposed as a means for measuring the distance from the object to be measured.

However, when a survey meter having the telescopic bar is used, an operation of extending and contracting the telescopic bar is required each time measurement is performed, which is complicated and impractical. In addition, the distance from the measurement target specified by law is 1
When it exceeds m, for example, when it is 2 m in a transportation ship, there is a problem that measurement cannot be performed.

On the other hand, to measure the dose equivalent rate, it is necessary to specify not only the distance from the object to be measured but also the portion to be measured in the object to be measured from the viewpoint of preventing measurement error. However, in the conventional survey meter, the measurer cannot confirm where in the measurement object is measured as the measured portion. In such a case, whether or not the point to be measured and the portion to be measured in the measurement target that is actually measuring match with the sense of the individual measurer,
Since the judgment is made based on experience, intuition, etc., there is a problem that individual differences and measurement errors are likely to occur in measured values.

The present invention solves the above problems and makes it possible to easily measure the dose equivalent rate or the like required to be measured at a place where the distance and angle from the object to be measured are constant, with high accuracy without individual differences or measurement errors. Moreover, it aims at providing the survey meter which can measure simply.

[0008]

According to a first aspect of the present invention for solving the above-mentioned problems, there is provided distance measuring means for measuring the distance from the object to be measured using laser light, and radiation from the object to be measured. And a display unit for displaying the distance from the measurement target measured by the distance measurement unit and the amount of radiation from the measurement target measured by the radiation measurement unit. It is a survey meter.

[0009]

In the survey meter according to the present invention, the distance measuring means emits laser light to the object to be measured and receives laser light reflected by the object to be measured. At this time, the distance measuring means measures the distance from the measurement object based on the time from the emission of the laser beam to the reception of the laser beam. Then, the display means displays the distance. Further, the radiation measuring means measures the amount of radiation from the measurement target. Then, the display means displays the amount of the radiation.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of a survey meter according to the present invention will be described below with reference to the drawings. The present invention is not limited to the following embodiments.

FIG. 1 is a schematic explanatory view showing an embodiment of a survey meter according to the present invention.

The survey meter 1 has a radiation measuring unit 2, a distance measuring unit 3, a display unit 4, a laser power source 10 and a grip 12.

The radiation measuring means 2 has a dose equivalent including an operation unit (not shown) having a power switch, a range change switch, a zero point adjustment dial, a time constant change switch, etc., and an ionization chamber for measuring the radiation from the object to be measured. The rate measuring unit 5. The dose equivalent rate measuring unit 5 is arranged in front of the survey meter 1.

The distance measuring means 3 has a sensor (not shown) having a function of emitting visible laser light to the object to be measured and receiving visible laser light reflected by the object to be measured, and the sensor emitting visible laser light. The laser receiving and emitting device 6 is provided with a measuring circuit (not shown) having a function of measuring the distance from the object to be measured based on the time required to receive light. The laser light emitting and receiving device 6 is arranged below the dose equivalent rate measuring unit 5.

As shown in FIG. 2, the display means 4 includes a dose equivalent rate display section 8 for analog-displaying the value of the dose equivalent rate measured by the dose equivalent rate measuring section 5, and the laser light receiving and emitting device 6. Distance display section 9 for digitally displaying the distance from the measurement object to be measured, and laser light emitting and receiving device switch 1
1 is a panel section 7 including The panel section 7 is arranged at the rear of the dose equivalent rate measuring section 5.

The laser power source 10 is arranged inside the survey meter 1. Further, the grip 12 is arranged below the laser light emitting and receiving device 6.

In the survey meter 1 of this embodiment, the dose equivalent rate measuring unit 5, the laser light emitting and receiving device 6, the panel unit 7, the laser power source and the grip 12 are integrally formed.

Next, the operation of the survey meter 1 of this embodiment will be described.

In the case of measuring the dose equivalent rate using the survey meter 1, first, at the planned measurement location, the measurer holds the grip 12 and targets the sensor in the laser light emitting and receiving device 6 of the survey meter 1 to the measurement object. Turn. Next, the laser light emitting and receiving device switch 11 on the panel portion 7 is turned on. Then, the visible laser light is emitted from the sensor toward the measurement target by the power from the laser power source 10. The emitted visible laser light travels straight and is irradiated onto the measurement target. At this time, the portion to be measured in the measuring object irradiated with the visible laser light is brightly colored, and therefore can be easily visually checked and confirmed by the measurer. Then, the visible laser light applied to the measurement target is reflected at an angle equal to the incident angle. At this time, if the sensor and the measurement target are not perpendicular to each other, visible laser light reflected from the measurement target is not received by the sensor. On the other hand, when it is vertical, the visible laser light reflected from the measuring object is received by the sensor. Then, the laser light emitting and receiving device 6 measures the distance from the measurement target based on the time from the emission of the visible laser light to the reception of the visible laser light. This distance is
It is digitally displayed on the distance display section 9 of the panel section 7. The distance displayed by the distance display unit 9 and the target distance to be measured are matched by the measurer.
The survey meter 1 is arranged at a position and an angle from the measurement target.

Next, when the measurer turns on the power switch in the radiation measuring section 5, the ionization chamber in the radiation measuring section 5 detects the radiation from the measurement object and measures the dose equivalent rate. The value of the dose equivalent rate is displayed in analog form on the dose equivalent rate display section 8 of the panel section 7.

According to the survey meter of the present invention, since the distance from the object to be measured is measured by using the laser light having the characteristics that it is excellent in straightness and its width does not spread, it is easy and simple with high accuracy. The distance can be measured and the position of the measurer can be specified in a short time. Further, the dose equivalent rate at an arbitrary distance from the measurement target can be measured. Moreover, since the measured portion of the measuring object is illuminated with the laser beam, the measurer can easily visually confirm and specify the measured portion. In this case, the measurement can be performed while easily keeping the distance and the angle to the measurement target constant.

Therefore, according to the survey meter according to the present invention, the measurement of the dose equivalent rate required to be measured at a place where the distance and angle from the measurement object are constant depends on the sense, experience, intuition, etc. of the individual measurer. Can be done without As a result, the measurement value can be measured easily and easily with high accuracy without causing individual differences or measurement errors.

The present invention is not limited to the above-mentioned embodiment, but can be appropriately modified according to the purpose.

The survey meter according to the present invention can measure various radiation doses such as irradiation dose other than the dose equivalent rate.

Instead of the ionization chamber in the dose equivalent rate measuring unit 5, a radiation measuring instrument known per se such as a GM (Geiger-Muller) counter, a proportional counter, a scintillation counter, etc. is appropriately selected according to the purpose. be able to.

The sensor in the laser light emitting and receiving device 6 is configured to emit laser light in front of the survey meter 1, but it may be configured to emit laser light in the lateral direction.

The laser light used in the laser light emitting and receiving device 6 is, for example, a compound semiconductor laser such as gallium alloy (red), He-Ne, Ar,
Ion laser such as Kr, polymethine type (green to far infrared), oxazine type (red to near infrared), xanthine type (yellow to red), coumarin type (purple to green), scintillator material (ultraviolet to blue), etc. Visible laser light such as a dye laser can be used. In the present invention, the visible laser light may be used alone, or the distance from the measuring object may be measured by using a non-visible laser light such as CO ₂ laser to identify the portion to be measured in the measuring object. It may be performed using the visible laser light.

The laser light emitting and receiving device 6 does not have to be provided integrally with the survey meter 1, but it may be provided at another location and the visible laser light generated there may be introduced into the survey meter 1 using an optical fiber or the like for use. You can also

The dose equivalent rate display section 8 and the distance display section 9 may be digital display or analog display and are not particularly limited.

The laser power source 10 may not be built in the survey meter 1 and may be arranged at another location. In such a case, power can be introduced from the laser power source 10 to the survey meter 1 using a known power cord or the like.

The grip 12 is not limited to the lower part of the survey meter 1, but may be provided as an upper grip, for example.

The radiation measuring means 2, the distance measuring means 3 and the display means 4 in the present invention do not have to be constructed integrally, and for example, only the display means 4 can be arranged separately and independently. At this time, the radiation measuring unit 2, the distance measuring unit 3, and the display unit 4 can be connected by using, for example, a cable. Also, each of these means
The structure may be operated by independent switches or may be operated by a single switch.

[0033]

[Effect] According to the present invention, the dose equivalent rate and the like required to be measured at a constant distance and angle from the object to be measured can be easily and simply produced with high accuracy without causing individual differences or measurement errors. It is possible to provide a survey meter that can measure.

[Brief description of drawings]

FIG. 1 is a schematic explanatory view showing an embodiment of a survey meter according to the present invention.

FIG. 2 is a schematic explanatory view showing an example of display means when viewed in the direction of the arrow in FIG.

[Explanation of sign]

 1 Survey Meter 2 Radiation Measuring Means 3 Distance Measuring Means 4 Display Means 5 Dose Equivalence Rate Measuring Section 6 Laser Receiving / Emitting Device 7 Panel Section 8 Dose Equivalence Rate Displaying Section 9 Distance Displaying Section 10 Laser Power Supply 11 Laser Receiving / Emitting Equipment Switch 12 Grip Hand

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[Procedure amendment]

[Submission date] March 25, 1993

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Correction target item name] All drawings

[Correction method] Change

[Correction content]

[Figure 1]

[Fig. 2]

Claims (1)

[Claims] 1. A distance measuring means for measuring a distance from a measuring object by using a laser beam, a radiation measuring means for measuring an amount of radiation from the measuring object, and a measuring object measured by the distance measuring means. A survey meter, comprising: a display unit that displays the distance and the amount of radiation from the measurement target measured by the radiation measurement unit.