Device for automatically adjusting pressure of flowing gas

Abstract

The invention discloses a device for automatically adjusting the pressure of flowing gas, comprising a vacuum gauge and a valve body. The device is characterized in that the valve body is a fine-adjustment valve body the air inlet end of which is provided with an air inlet joint and a fine-adjustment air inlet valve, the gas transmission end is provided with a vacuum detection head, a piezoelectric ceramic valve is arranged between the fine-adjustment air inlet valve and the vacuum detection head, the signal output end of the vacuum detection head is connected with the input end of the vacuum gauge through a first wire, the output end of the vacuum gauge is connected with the input end of a piezoelectric controller through a data wire, a digital/analogue converter and a second wire, the output end of the piezoelectric controller is connected with the control end of the piezoelectric ceramic valve through a third wire and a sealed conductive plate on the fine-adjustment valve body, and the gas transmission end of the fine-adjustment valve body is provided with a threaded joint to facilitate sealing connection with a container into which the flowing gas is to be input. The device has simple structure, easy operation and great practical value under the experimental condition that the air pressure is lower than 100torr and the stability thereof needs to be accurately controlled.

Description

technical field [0001] The invention relates to an automatic regulating device for flowing air pressure, in particular to an automatic regulating device for flowing gas pressure at low air pressure (below 100 Torr). Background technique [0002] Higher harmonic technology is the synthesis of a single attosecond (10 -18 second) level ultrashort pulse and the main experimental method for generating X-rays in the water window band, because a single attosecond level ultrashort pulse can be used to study the movement of electrons in atoms or molecules, and X-rays in the water window band can be used in biological imaging It plays an extremely important role, so the research on high-order harmonic technology is very popular in today's world. [0003] The current development of high-order harmonic technology is mainly to study the interaction between laser and gas, mainly by changing the femtosecond laser field, gas type, gas pressure, gas box length, the relative position of the ...

AI Technical Summary

Problems solved by technology

The acquisition time of high-order harmonic signals is generally a few seconds to tens of seconds. If the signal is relatively strong, the required acquisition time is relatively short. It is feasible to use the method of manually adjusting the fine-tuning valve, but the signal is often very weak in current experiments. The required acquisition time is as long as several minutes. In this case, the method of manually adjusting the fine-tuning valve has great disadvantages. First, the precision of the fine-tuning valve is not high, and the air pressure will change greatly if it is rotated at a very small angle. , it is difficult to adjust accurately; secondly, the operator concentrates on adjusting the air pressure in real time for a long time, and the longer the time, the worse the adjustment effect will be; harmful to the experimenter

In short, changes in air pressure will affect the interaction process between gas and laser, so that we cannot get the high-order harmonics we want

[0004] At present, the air pressure is adjusted by manually adjusting the fine-tuning valve method, which usually makes the high-order harmonic spectrum (such as figure 1 As shown, the abscissa is the photon energy, the unit is electron volts, and the ordinate is the harmonic intensity, and the unit is the atomic unit) and the higher harmonic spectrum obtained by theoretical simulation under the same parameters (such as figure 2 As shown, the selection of the abscissa and the ordinate is the same as figure 1 ) is not the same, because the air pressure value is fixed during theoretical simulation, but it cannot be realized in the experimental process

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