JPH0560866A - Reader of fluorescent glass dosemeter - Google Patents

Abstract

PURPOSE:To instantaneously set the optimum diaphragm to a glass element of an arbitrary kind, to easily eliminate the difference of a measuring condition between glass holders and to shorten a measuring time to a large extent. CONSTITUTION:A diaphragm plate 21 provided with two or more kinds of diaphragms 21a-21d is arranged on the exciting light incident side of the glass element 2 held by a glass holder 25 and a diaphragm plate 23 provided with two or more kinds of diaphragms 23a-23d in the same way is arranged on the fluorescence emitting side of the glass element 2. Further, a kind discrimination mark is applied to the glass holder 25 and read by a sensor 27 to rotate the diaphragm plates 21,23 and the diaphragm fitted to the kind of the glass element 2 is set to a predetermined light path position.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fluorescent glass dosimeter reading device for reading an exposure dose of a fluorescent glass dosimeter element (hereinafter referred to as a glass element), and in particular, an arrangement mechanism of a glass element and a diaphragm is improved. Fluorescent glass dosimeter reader.

[0002]

2. Description of the Related Art Generally, after exposure to radiation, a purple light of a predetermined wavelength
This glass element that emits fluorescence by external excitation, this glass
Fluorescent glass holder for holding the element, this fluorescent glass holder
The holder case that holds the rudder so that it can be carried is the user
Various things have been developed according to the purpose of use.
By the way, with the glass element, P8 (8
× 8 ×^t 4.7 mm), P15 (15 x 12 x^t 3.5
mm), P16 (16 x 16 x^t 1.5 mm), P34
(34 x 12 x^t 1.5mm) etc., detection of finger exposure
Has P6 (6 × 6 ×^t 3.3mm), for in vivo exposure detection
Is R1 (φ1 ×^l 6), P8 and P1 for air dose detection
5, P34, etc. In addition, here, P6, P8, P1
5, R1 ... Means the model number.

By the way, in the measurement of the exposure dose of a glass element, excitation ultraviolet rays are made to enter from one surface of the glass element to the glass element which has been exposed to the radiation as described above, and The fluorescence is emitted from the other surface of the glass element in the direction orthogonal to the incident direction, and the fluorescence emitted from the glass element is detected by a photomultiplier tube to measure the exposure dose of the glass element. At this time, the excited ultraviolet rays are irradiated not only on one surface of the glass element but also on the peripheral portion other than the glass element, so that fluorescence is emitted from the peripheral portion and causes a measurement error.
Therefore, from the viewpoint of preventing the generation of fluorescence from such an unnecessary portion, as shown in FIG.
A diaphragm 3 for regulating the ultraviolet ray incident area and the incident position is arranged on the ultraviolet ray incident side of the glass element 2 held by the glass element 2, and the fluorescence emitted from the glass element 2 is fixed on the other surface side (fluorescence measuring side) of the glass element 2. A diaphragm 4 for passing only the area is arranged.

FIG. 5 is a view showing a typical example of the glass element 2 and the diaphragms 3 and 4 for the glass element 2. FIG. 3A is a front view of the fluorescence incident side diaphragm 3.
FIG. 1B is a front view of the fluorescence measurement side diaphragm 4, and FIG. 1C is a perspective view of the glass element 2. In the case of the diaphragms 3 and 4 on the right end side in the drawing, the diaphragms 3 and 4 are set so as to correspond to the respective arrow positions of the glass element 2 while being moved by a predetermined distance.

Next, the structure of a conventional fluorescent glass dosimeter reading device will be described. There are two types of this reading device,
One of them has a structure as shown in FIG. In this reading device, a glass holder 1 for measurement, in which diaphragms 3 and 4 of the same shape are attached in advance, is set at each measurement position on a turntable 5, and then the turntable 5 is rotated by a sample exchanger 7 during actual measurement. While doing so, the glass elements 2 that have received the exposure dose are sequentially mounted on the glass holder 1 artificially or mechanically, and the exposure dose of the glass element 2 is measured in the manner described below.

That is, the laser beam from the N ₂ laser 8 is incident on the semitransparent mirror 11 made of quartz glass through the ultraviolet ray transmitting filter 9 and the reflecting mirror 10, and is separated into the reflected light and the straight traveling light here. Among them, the reflected light is the standard fluorescent glass 12,
The light is received by the photodiode 15 through the ultraviolet cut filter 13 and the red transmission filter 14, and the output of the photodiode 15 is used for sensitivity adjustment in a measurement output described later, that is, as a calibration signal.

On the other hand, the straight traveling light passes through the diaphragm 3 and enters one surface of the glass element 2 as excitation ultraviolet light.
At this time, fluorescence is generated from the other surface of the glass element 2. This fluorescence passes through the diaphragm 4, and then passes through the interference filter 16, the ultraviolet cut filter 17, and the red transmission filter 18 to the photomultiplier tube 19. It is introduced, where an electrical signal proportional to the radiation dose of the glass element 2 is measured and output.

Next, another conventional fluorescent glass dosimeter reading device has a diaphragm 3 and a diaphragm 4 in advance as shown in FIG.
The attached glass holder 1 is installed, and in this state, the glass element 2 is automatically loaded from the automatic sample changer 20,
It is the structure which measures the exposure dose of the said glass element 2.

[0009]

However, in the reading device shown in FIG. 6, the same kind of glass holder 1, diaphragms 3, 4 and the like are installed at each measurement position on the turntable 5, but in reality, these are used. Since the glass holder 1, the working accuracy of the diaphragms 3, 4 and the mounting positions are slightly displaced, the measurement conditions are different between the glass holders 1, 1 ..., As a result, highly accurate measurement cannot be performed.
Therefore, in order to make the measurement conditions of the glass holders 1, 1 ... The same, it is possible to measure the exposure dose of the glass element 2 using one specific measurement position on the turntable 5. However, in this case, there is a problem that the measurement takes a long time.

Further, in this reading apparatus, only the exposure dose of one type of glass element 2 can be measured, which is naturally restricted by the problem of the measurement range, and it is often inconvenient in handling. Therefore, in order to be able to measure the exposure dose of various types of glass elements 2, different glass holders 1 and diaphragms 3, 4 are provided at the respective measurement positions on the turntable 5.
However, in this case, the dimensional error, the holding state of the glass element 2 and the like are more and more different, and there is a problem that the measurement conditions are different for each glass holder 1 ,. On the other hand, in the latter reading device shown in FIG. 7, only one type of glass element 2 can be applied exclusively, and there is a problem of lacking flexibility in measurement as described above.

The present invention has been made in view of the above circumstances, and when setting the measurement position of a glass element of an arbitrary type among a plurality of types of glass elements, it is possible to automatically set an optimum diaphragm, and An object of the present invention is to provide a fluorescent glass dosimeter reading device that eliminates the difference in measurement conditions between holders and can significantly reduce the measurement time.

[0012]

In order to solve the above problems, the present invention sets a glass holder for holding a glass element in a predetermined measurement position and reads the exposure dose of the glass element. In, the type identification target attached to the predetermined portion of the glass holder, the type determination means for detecting the type identification target to determine the type of the glass element, the excitation light incident side and the fluorescence of the glass element to be measured. A diaphragm plate provided with a plurality of types of diaphragms respectively corresponding to the type of the glass element is installed on the emission side, and a desired diaphragm of each diaphragm plate is determined based on the type determination signal obtained by the type determination means. And a diaphragm setting means for setting the optical path position.

[0013]

Therefore, according to the present invention, by taking the above-mentioned means, the glass holder for holding the glass element is set at the measurement position, or after the position is set.
The type identification sensor detects the type identification target attached to the glass holder to determine the type of the glass element and sends it to the diaphragm setting means. Here, the diaphragm setting means, when receiving the type determination signal, rotates each diaphragm plate on the excitation light incident side and the fluorescence emission side, for example, to arrange a desired diaphragm on a predetermined optical path. Therefore, a diaphragm suitable for the type of glass element can be immediately and automatically set, and since many kinds of diaphragms are provided on the same diaphragm plate, problems such as dimensional error can be solved.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a schematic configuration diagram of the entire apparatus, FIG. 2 is a diagram for explaining the relationship between a glass element held by a glass holder and a diaphragm, and FIG. 3 is a diagram showing marks for identifying the type of glass element. In these figures, the same parts as those in FIG. 6 are designated by the same reference numerals, and detailed description thereof will be omitted. Hereinafter, different parts will be described particularly in comparison with the conventional device.

That is, in this reading device, a diaphragm plate 21 provided with a plurality of types of diaphragms 21a, 21b, 21c, 21d is arranged on the ultraviolet ray incident side as shown in FIGS. There is provided a diaphragm exchanger 22 which rotates the diaphragm plate 21 based on the glass element type determination signal from and sets the desired diaphragm, for example, 21a at the ultraviolet ray incident position.

On the other hand, on the fluorescence emission side of the glass element 2, a diaphragm plate 23 provided with a plurality of types of diaphragms 23a, 23b, ... Is similarly arranged as shown in FIGS. There is provided a diaphragm exchanger 24 that rotates the diaphragm plate 23 based on the glass element type signal to set a desired diaphragm 23a at a predetermined position on the fluorescence emission side.

The diaphragms 21a, 21b,
Has a role of determining the incident area and position of the excitation ultraviolet ray, and is determined exclusively by the type of the glass element 2. Further, the diaphragms 23a, 23b, ...
It has a role of allowing a certain area to pass the amount of fluorescence emitted from, and is similarly determined by the type of the glass element 2. Therefore, although the diaphragm shapes on the ultraviolet incident side and the fluorescence generating side have a pair relationship in advance, they may be appropriately and selectively used without having a pair relationship with each other.

Reference numeral 25 is a glass holder for holding the glass element 1. The glass holder 25 is a sample exchanger 2.
6 is set to the measurement position, and a type identification mark 27 for identifying the type of the glass element 2 is attached at a predetermined position of the glass holder 25. FIGS. 3A to 3C are views showing the type identification mark 27 attached to the glass holder 25. Reference numeral 28 denotes a type determination sensor that reads the type identification mark 27 and determines the type of the glass element 2.

Next, the operation of the apparatus configured as described above will be described. First, prior to measurement, the sample exchanger 2
The glass rudder 25 holding the glass element 2 is set to the measuring position by 6. Then, the type determination sensor-28 reads the type identification mark 27 attached to the glass holder 25 to determine the type of the glass element 2, and sends the type determination signal to the diaphragm exchangers 22, 24.
Send to. It is also possible to easily read the type identification mark 27 by using the type determination sensor-28 while setting the glass holder 25.

Here, each diaphragm exchanger 22, 24
When receiving the type determination signal from the type determination sensor 28, the corresponding diaphragm plates 21 and 23 are rotated by a predetermined angle to arrange the diaphragms 21a and 23a corresponding to the type of the glass element 2 on a predetermined optical path.

Thereafter, when a laser beam is generated from an N ₂ laser as an exciting ultraviolet ray source, this laser beam passes through the ultraviolet ray transmitting filter 9 and the reflecting mirror 10 and the quartz glass anti-reflecting mirror 11 is formed.
Is introduced into the light source, where it is separated into reflected light and straight light. The reflected light obtained by the anti-reflecting mirror 11 is received by the photodiode 15 through the standard fluorescent glass 12, the ultraviolet cut filter 13, and the red transmission filter 14, and is used for sensitivity adjustment of the measurement output, that is, a calibration signal.

On the other hand, the rectilinear light is transmitted to the diaphragm 21a.
Then, it enters the one surface of the glass element 2 as excited ultraviolet light. At this time, fluorescence is generated from the other surface of the glass element 2, and this fluorescence is introduced into the photomultiplier tube 19 after passing through the diaphragm 23a, passing through the interference filter 16, the ultraviolet cut filter 17, and the red transmission filter 18. Then, an electric signal proportional to the exposure dose of the glass element 2 is measured and output.

Therefore, according to the configuration of the above embodiment, the type identification sensor 27 detects the type identification mark 27 from the type identification sensor 28 during the transfer of the glass holder 25 holding the glass element 2 of an arbitrary type or after the setting of the measurement position. Glass element 2
The optimum diaphragm is automatically set at a predetermined position on the basis of the result of the judgment, so that the diaphragm can be set very quickly and a plurality of kinds of glass elements 2 can be set by using one device. The dose of radiation can be measured, and the efficiency of measurement work can be greatly improved. Moreover, since the same type of glass element 2 is always measured by using the same diaphragm and diaphragm plate, there is no problem of processing accuracy and positional deviation between the glass holders 25 as in the conventional case, and the exposure dose is the same under the same measurement conditions. Can be measured, and the reliability can be greatly improved as compared with the conventional device.

Further, in the apparatus of the present invention, a plurality of glass holders 25 can be set at each measurement position on the turntable 5 by using the sample exchanger 26 as shown in FIG. The glass elements 2 of different types can be continuously measured under the same conditions, and the time required for the measurement can be greatly shortened.

In the above embodiment, the same glass holder 25 is set at the measurement position, but the same applies to the case where a plurality of different glass holders 25 are set. Further, although the glass holder 25 is marked in the above embodiment, the type may be determined using various conventionally known identifying means. Further, although the diaphragm plates 21 and 23 are of a rotary type, a plurality of types of diaphragms are provided on a long plate body at predetermined intervals, and a desired diaphragm is set at a predetermined position by a slide type based on a type determination signal. But it's okay. Besides, the present invention can be variously modified and implemented without departing from the scope of the invention.

[0026]

As described above, according to the present invention, when setting the measurement position of any type of glass element among a plurality of types of glass elements, it is possible to immediately and automatically set the optimum diaphragm, and It is possible to provide a fluorescent glass dosimeter reader that can easily eliminate the difference in measurement conditions between glass holders and can significantly reduce the measurement time.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing an embodiment of a fluorescent glass dosimeter reading device according to the present invention.

FIG. 2 is a diagram showing a relationship between a glass element and a diaphragm.

FIG. 3 is a view showing a mark for identifying the type of glass element.

FIG. 4 is a diagram illustrating a mutual positional relationship between a conventional general glass element, a diaphragm, and a glass holder.

FIG. 5 is a diagram showing a typical example of a glass element and a diaphragm.

FIG. 6 is a schematic configuration diagram of a conventional device.

FIG. 7 is a schematic configuration diagram of another conventional device.

[Explanation of symbols]

2 ... Glass element, 21, 23 ... Diaphragm plate, 21a
-21d, 23a-23d ... Diaphragm, 22, 24
… Diaphragm changer, 25… Glass holder, 26…
Sample exchanger, 27 ... Type identification mark, 28 ... Type determination sensor.

Claims (1)

[Claims] 1. A fluorescent glass dosimeter reading device for setting a glass holder holding a glass element at a predetermined measurement position and reading the exposure dose of the glass element, wherein a type identification target attached to a predetermined portion of the glass holder. And a type determination means for detecting the type identification target to determine the type of the glass element, and a plurality of types corresponding to the type of the glass element on the excitation light incident side and the fluorescence emission side of the glass element to be measured, respectively. A diaphragm plate provided with a diaphragm is installed, and a diaphragm setting unit that sets a desired diaphragm of each diaphragm plate to a predetermined optical path position based on the type determination signal obtained by the type determination unit is provided. Fluorescent glass dosimeter reader.