METHOD AND SYSTEM FOR CONTROLLING X-RAY FOCAL SPOT CHARACTERISTICS FOR TOMOSYNTHESIS AND MAMMOGRAPHY IMAGING

摘要

An x-ray tube is described that includes components forincreasing x-ray image clarity in the presence of a moving x-ray source bymodifying focal spot characteristics, including focal spot size and focal spotposition, tn a first arrangement a static focal spot is moved in a directioncontrary to the movement of the x-ray source so that an effective focal spotposition is essentially fixed in space relative to one of the imaged objectand/or detector during a tomosynthesis exposure. In a second arrangement,the size of the static focal spot is increased, and the resulting increase intube current reduces the exposure time and concomitant blur effect. Themethods may be used alone or in combination; for example an x-ray tubewith a larger, moveable static focal spot will result in a system that fullyutilizes the x-ray tube generator, provides a high quality image with reducedblur and, due to the decrease in exposure time, may scan the patient morequickly.