Now the high frequency of X-ray cameras have been gradually replaced the industrial frequency X-ray cameras, so high frequency X-ray cameras, which have characteristics and advantages?
Perlong high frequency X-ray generator features below:
1, the patient's skin dose low: industrial frequency machine especially single-phase full-wave rectifier X-ray machine, the high voltage transformer is pulstin current output waveform, ripple coefficient 100%, on imaging without any help more soft rays composition. High-frequency machine high voltage generator is similar to the output waveform constant dc, pulse rate is very low, corrugated coefficient "plus or minus 5%, the output of the X-ray energy oneness, the patient's skin greatly improve greatly reduced dose.
2, the image quality high: the continuous spectrum of x line, and the material of the absorption don't abide by the rules index, the rays through the material after, not only have the reduction of the number of photons, but also the photon energy changes, the image quality is poorer. And single can narrow beam X-ray, material to the absorption abide by law index, the rays through material later, only the reduction of the number of photons, no photon energy change, to improve the image quality is very favorable.
3, output dose great: for high frequency machine is a constant dc exposure, therefore, in the film to get the same black of c, high-frequency machine power frequency value is mAs 60% of the machine. For example the total wave rectifier single X-ray machine, a pulse duration for 10 ms, more than 0.707 times of peak for time is about 5 ms, and high frequency machine constant dc exposure of 10 ms is the single dose of x line machine wave dc exposure of ms 20 doses. If exposure in the same time, high frequency machine use 300 mA provides X-ray dose and single phase all the wave rectifier X-ray machine 500 mA provide basic same x line dose.
4, real-time control: in the process of exposure to kV and mA real-time control. High-frequency machine kV usually by dc inverter to adjust the output pulse frequency, inverter frequency output not only by kV set data control, are also affected by kV detection signal control, in the process of exposure, the output frequency can be set according to the test signal and the result is rapidly tracking adjustment, to ensure that the actual value is equal to set data kV. And power frequency of the machine by self cou pling transformer is kV regulation, although in exposure compensation can before, but once the exposure start, to prevent carbon round mobile produce arc, and because the exposure time, carbon wheel drive system inertial couldn't keep up with the change of the mechanical electrical signal, when the power supply voltage fluctuations or other factors of tube voltage change cannot control, so that the actual value tube voltage and deflection value. In addition, high frequency machine mA usually by dc inverter to adjust the output pulse width, inverter output pulse width not only by mA set data control, are also affected by filament heating or mA detection signal control, in the process of exposure, the output pulse width can be set according to the test signal and compare the results of the track quickly adjust to ensure that mA the actual value equal to the value. And power frequency of mA adjustment circuit is machine needs, set up manostat, while still need space charge to compensate, although taken a lot of measures, mA the actual value and value are still worse error. Real-time control still can make the high frequency X-ray machine exposure of repeatability of book greatly increased.
Article: from perlong medical (http://www.pl999.net)
Attention: if you want to copy this article , you must attach the website.
Perlong high frequency X-ray generator features below:
1, the patient's skin dose low: industrial frequency machine especially single-phase full-wave rectifier X-ray machine, the high voltage transformer is pulstin current output waveform, ripple coefficient 100%, on imaging without any help more soft rays composition. High-frequency machine high voltage generator is similar to the output waveform constant dc, pulse rate is very low, corrugated coefficient "plus or minus 5%, the output of the X-ray energy oneness, the patient's skin greatly improve greatly reduced dose.
2, the image quality high: the continuous spectrum of x line, and the material of the absorption don't abide by the rules index, the rays through the material after, not only have the reduction of the number of photons, but also the photon energy changes, the image quality is poorer. And single can narrow beam X-ray, material to the absorption abide by law index, the rays through material later, only the reduction of the number of photons, no photon energy change, to improve the image quality is very favorable.
3, output dose great: for high frequency machine is a constant dc exposure, therefore, in the film to get the same black of c, high-frequency machine power frequency value is mAs 60% of the machine. For example the total wave rectifier single X-ray machine, a pulse duration for 10 ms, more than 0.707 times of peak for time is about 5 ms, and high frequency machine constant dc exposure of 10 ms is the single dose of x line machine wave dc exposure of ms 20 doses. If exposure in the same time, high frequency machine use 300 mA provides X-ray dose and single phase all the wave rectifier X-ray machine 500 mA provide basic same x line dose.
4, real-time control: in the process of exposure to kV and mA real-time control. High-frequency machine kV usually by dc inverter to adjust the output pulse frequency, inverter frequency output not only by kV set data control, are also affected by kV detection signal control, in the process of exposure, the output frequency can be set according to the test signal and the result is rapidly tracking adjustment, to ensure that the actual value is equal to set data kV. And power frequency of the machine by self cou pling transformer is kV regulation, although in exposure compensation can before, but once the exposure start, to prevent carbon round mobile produce arc, and because the exposure time, carbon wheel drive system inertial couldn't keep up with the change of the mechanical electrical signal, when the power supply voltage fluctuations or other factors of tube voltage change cannot control, so that the actual value tube voltage and deflection value. In addition, high frequency machine mA usually by dc inverter to adjust the output pulse width, inverter output pulse width not only by mA set data control, are also affected by filament heating or mA detection signal control, in the process of exposure, the output pulse width can be set according to the test signal and compare the results of the track quickly adjust to ensure that mA the actual value equal to the value. And power frequency of mA adjustment circuit is machine needs, set up manostat, while still need space charge to compensate, although taken a lot of measures, mA the actual value and value are still worse error. Real-time control still can make the high frequency X-ray machine exposure of repeatability of book greatly increased.
Article: from perlong medical (http://www.pl999.net)
Attention: if you want to copy this article , you must attach the website.
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