| 摘要 |
<p>In an all electronic multi energy system at least two levels of x-ray energy are produced sequentially and rapidly at independently controllable and different power or flux levels. In the system there are a triode x-ray tube (1) which selects the operating current of the system and a series connected temperature limited diode (2) or triode which controls the voltage across the first x-ray tube. This system provides improved performance in x-ray imaging applications at low cost, for example, in baggage inspection or measurements of bone densities and medical fluoroscopy. The objective of the system is to produce a maximum amount of useful information with a minimum amount of exposure for the patient or object to be illuminated by x-ray flux. With human patients this is desirable for health safety reasons; for baggage inspection, to reduce exposure to photographic films.</p> |
