SU1128307A1 - Process for measuring resolution time of photomultiplier tube - Google Patents

Abstract

METHOD OF MEASURING RESOLUTION BP | IMPORTANCE OF A PHOTO-ELECTRON MULTIPLE, including measuring the time delay between the electrical signals at the output of the photomultiplier by the action of light: sensitivity: characterized in that, in order to improve the accuracy of measuring the resolution time of a photomultiplier at the upper limit of the dynamic range when the output signal is saturated, the photomultiplier is irradiated with a light pulse causing the anode current of the PMT to saturate and the reference light pulse corresponding to the upper limit linearity of the amplitude characteristic of the photomultiplier, and change the delay time between pulses to obtain a given level of nonlinearity 9 epernogo signal and as an information parameter of the resolving time Image: electron multiplier using the received delay time between pulses.

Description

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one

{The invention relates to electronic engineering, in particular, to methods for measuring parameters of photomultipliers (PMT), and can be used in the field of photometry of photosensitive devices.

There is a known method for measuring the defrosting time of radio engineering installations (dead time) using a pulse generator and an oscilloscope. In this case, the minimum time interval between two pulses is determined, at which both pulses are reliably recorded by measuring radio equipment II.

The disadvantage of the method applies. its accuracy is relatively low.

The closest to the invention of the JIO technical entity is the method of measuring, permitting the time of a photomultiplier on a pair of light pulses or using two trains of pulses that converge in time, close to their complete merging with an adjustable delay line, including measuring the time delay electrical signals at the PMT output. Since measurements of this kind are most often carried out to compare various structures, a standardizing measurement is introduced that relates to one of the main parameters of a photomultiplier, for example, the anodic sensitivity of a photomultiplier {2J.

The disadvantages of this method are the lack of accurate quantitative criteria by which the resolution time can be recorded at the upper limit of the dynamic range. It is especially difficult in the absence of accurate assessment criteria to determine the resolution time with a powerful light pulse, causing the anode current of the photomultiplier to saturate, preceding the appearance of a useful rvetovrgo signal.

The purpose of the invention is to improve the accuracy of measuring the resolution time at the upper limit of the dynamic range when the output signal of the photomultiplier is saturated.

This goal is achieved in that according to the method of measuring the resolution time of the photomultiplier, including the measurement of the time delay between the electrical signals at the output. photomultiplier at. impact on

28307g

It is irradiated with light pulses, in the mode of a predetermined anodic sensitivity, by a photomultiplier, with a power pulse causing a saturation of the anodic current of the photomultiplier

10 pulses up to a predetermined level of nonlinearity of the reference signal, and the received delay time is used as an information parameter about the PMT resolution time.

15 between pulses.

The essence of the method is that. if the power of the light pulse interference lies on top. ;: dynamic range of PMT (for

20 different types of PMT 10® - 1.0 W), at the output of the PMT a Powerful overload mode is created - anode current saturation. In this case, the anodic pulse due to over-voltage;

5 charge is strongly deformed, and its duration increases several times. Simultaneously with the impulse, the photomultiplier interference is irradiated with a reference light signal by a pulse of average power,

0 imitating the useful signal to the top of the jieM limit of the linearity of the amplitude characteristic of the photomultiplier.

Initially, the reference signal 5 is delayed relative to the interference signal for a certain time interval: low. By changing the delay time ti. (by bringing the interference pulse and the repertoire pulse) achieve a given 0 level of nonlinearity. The reference signal. In this case, the obtained time Ip is equal to the resolving time of the photomultiplier.

FIG. 1 is a schematic diagram of the installation for measuring a permit. stitching the photomultiplier time of the proposed method in FIG. 2 and 3 -. characteristic pulse waveforms.

The installation contains a PMT 1, the output of which is connected to a wideband pulse oscilloscope 2, to the second input of which is connected the output of the trigger generator j, the other two outputs of which are connected

with an optical quantum generator (RCG) 4 and a line 5 under the top, connected to LED 6, and a neutral calibrated absorber 7 of light,

Claims (1)

METHOD FOR MEASURING THE RESOLUTION TIME OF A PHOTOELECTRON MULTIPLIER, including measuring the time delay between electric signals at the output of a photomultiplier when exposed to light: pulses in a given anode mode; sensitivity: characterized in that, in order to increase ^{1 the} accuracy of measuring the resolution time of the photomultiplier at the upper boundary of the dynamic range when the output signal is saturated, the photomultiplier is irradiated with a light pulse with a power causing saturation of the PMT anode current, and a reference light pulse with a power corresponding to the upper the linearity limit of the amplitude characteristic of the photomultiplier, and the delay time between pulses is changed until a predetermined level of reference non-linearity is obtained signal and as an information parameter about the resolution time of the photo; The electron multiplier uses the obtained delay time between pulses. eleven