JPH03225293A - Integration type digital rate meter - Google Patents

Abstract

PURPOSE:To improve statistic accuracy with the lapse of time and to obtain a count value whose indication value is not sharply changed by displaying a counting rate value obtained by dividing an integrated value obtained by integrating values by an adder by the time required from detection start up to the current time. CONSTITUTION:When a radiant ray is injected into a detector 12, low pressure vapor (alcohol steam, etc.) is ionized, electric discharge is generated and a discharge current is instantaneously allowed to flow and A/D converted into a digital signal 100. The signal 100 is amplified by an amplifier 14 and the amplified digital signal 101 is counted by a counter 16. A sampling circuit 20 outputs a timing pulse 102 in each previously set time, the count value 103 of the counted signal 101 is outputted to an adder 18 in each timing and the counter 16 is reset by the count signal 103. The adder 18 integrates the count value 103 successively outputted from the counter 16 and outputs the total number 105 of counts from the count starting point up to the current point to a divider 24. The divider 24 calculates the count rate value, which is displayed on a display device 26.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an integrating digital rate meter that is used in radiation medical equipment and the like and displays input pulse values at a count rate.

[Prior Art] Conventionally, an integrating digital rate meter used in a radiation measuring device in radiation medical equipment is known. The counting rate value is calculated from the above, and this counting rate value is displayed on the display.

[Problem to be solved by the invention] Since the conventional integrating digital rate meter is configured as described above, when counting random pulses,
If the setting time is shortened, the indicated value will fluctuate due to statistical fluctuations, making it difficult to read.If the setting time is lengthened to suppress the fluctuation of the indicated value, the interval between the indicated value changes will become longer, causing the counted value to fluctuate. However, there was a problem in that the indicated value did not change immediately.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to provide an integrating digital rate meter whose statistical accuracy improves over time and whose indicated value does not fluctuate greatly.

[Means for Solving the Problems] The integrating digital rate meter according to the present invention includes a detector that detects input pulses, an adder that integrates the output from the detector from the time when detection starts to the present, and a A counter that counts the time from to the present, a divider that divides the integrated value accumulated by the adder by the time from the start of detection counted by the counter to the present, and a display that displays the count rate value calculated by the divider. It has a container.

[Operation] The integrating digital rate meter of the present invention detects human pulses using a detector, integrates the output from the detector from the start of detection to the present using an adder, and calculates the time from the start of detection to the present using a counter. is counted, and the divider divides the integrated value accumulated by the adder by the time counted by the counter from the start of detection to the present time, and the display displays the count rate value calculated by the divider.

〔Example] An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the configuration of the integrating digital rate meter according to the present invention. It has a detector 12 that detects the radiation as a discharge current by applying a DC high voltage between the tube wall and the tube wall, and converts the discharge current from analog to digital. An amplifier 14 for amplifying the digital signal 100 output from the detector 12 is connected.

A counter 16 for counting the digital signal 101 amplified by the amplifier 14 is connected to the output side of the amplifier 14, and the output side of the counter 16 is connected to a preset time, that is, an interval time for displaying the count rate value. (
An adder 18 is connected to add up the counts output from the counter 16 every Δt).

Further, a sampling circuit 20 that sets an interval time (Δt) and outputs a timing pulse 102 at every interval time (Δt) is connected to the counter 16, and the counter 16 counts every time it receives a timing pulse 102. It outputs the count of digital signal 101 and is reset by the output signal 103.

Furthermore, a counter 22 that counts the timing pulses 102 output from the sampling circuit 20 at every interval time (Δt) is connected to the output side of the sampling circuit 20, and the output side of the counter 22 and the adder 18 is , after starting counting, multiplying the total count 105 from the start of counting output from the adder 18 to the present by the total count number 104 of the timing pulse 102 output from the counter 22 by the interval time (Δt). A divider 24 is connected to calculate the count rate value by dividing by the time up to the present time (T1).

A display 26 that displays the count rate value calculated by the divider 24 is connected to the output side of the divider 24.

Next, the operation of this embodiment will be explained.

When radiation enters the detector 12, the low-pressure gas (alcohol vapor, etc.) sealed inside the detector 12 is ionized and a discharge occurs, a discharge current flows instantaneously, and this discharge current is A/D converted. The result is a digital signal 100.

Then, the digital signal 100 is amplified by the amplifier 14, and the amplified digital signal 101 is counted by the counter 16.

At this time, the sampling circuit 20 outputs the timing pulse 102 at every preset setting time (interval time) (Δt), and the counter 16 that receives the timing pulse 102 counts the timing pulse 102 every time it receives the timing pulse 102. The count 103 of the signal 101 is output to the adder 18 and is reset by the output signal 103.

Then, the adder 18 sequentially integrates the counts 103 output from the counter 16 and outputs the total count 105 from the start of counting to the present to the divider 24.

Further, the divider 24 which receives the total count 105 from the start of counting to the present from the adder 18 receives the total count 105 from the adder 18.
The time from the start of counting to the present (T1) is the total count number 104 of the timing pulses 102 output from the counter 22 that counts the timing pulses 102 output from the sampling circuit 20 multiplied by the interval time (Δt). Calculate the count rate value by dividing by .

Then, the count rate value calculated by the divider 24 is displayed on the display 26.

For example, R1 is the display counting rate (c p s) after the first interval time (Δt) after starting counting, and R1 is the display counting rate (c p s) after the first interval time (Δt) after starting counting.
) is the total number of 105 up to N.

The first interval time (Δ
t) is T1.If the count of the first interval is Jz interval time Δt, it can be expressed as follows.

When i-1, R1 When 1-2, R3 When 1-3, R3 5, 1-120, -nt / 0-5 - (nt + n 2 ) / 1 - (n 1 + n 2 + n s )/1.5 Here, when Δt-0°1-120, R120-(n 1 + n 2 +
...+n12o)/60 is displayed on the display 26.

In the above-mentioned embodiments, an ionization type detector was used as the detector, but the present invention is not limited to this type of detector.

[Effects of the Invention] As explained above, according to the present invention, the count rate value obtained by dividing the integrated value accumulated by the adder by the time from the start of detection to the present time is displayed, so that the count value can be easily calculated. When counting random pulses while maintaining the sensitivity of the indicated value due to fluctuations, it is possible to smooth the fluctuations in the indicated value and read the count rate value on the container.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an integrating digital rate meter according to the present invention. 0 2 8 2 4 6 Digital rate meter detector adder counter divider indicator.

Claims (1)

[Claims] A detector that detects input pulses, an adder that adds up the output from the detector from the start of detection to the present, a counter that counts the time from the start of detection to the present, and a counter that calculates the integrated value accumulated by the adder. An integrating digital rate meter comprising: a divider that divides by the time counted from the start of detection to the present; and a display that displays the count rate value calculated by the divider.