GENERATION OF X RAY EXPOSURE USING PHOTOCONDUCTOR AND APPARATUS FOR IMPLEMENTING THE SAME

摘要

PURPOSE: To decrease the artifacts in X-ray exposure by self-discharge by determining the self-discharge at respective image positions from the time elapsing from the precedent exposure before the end of charging, the discharge characteristic function of photoelectric conductors and the amplitude coefft dependent upon the dosage at the image points in the precedent exposure. CONSTITUTION: X-ray radiations are converted to charge images. These images are locally and evenly charged before the X-ray exposure and are discharged as the function of the X-ray radiation intensity by the exposure. The surface thereof is scanned for the purpose of detecting the charge densities after the exposure and the video values are formed for the respective image points. The X-ray exposure is radiated by the photoelectric conductors corresponding to the discharge at the image points. In such a case, the self-discharge of the photoelectric conductors in succession to the X-ray exposure is expressed as the product of radiation characteristic function f(t) of the time function-photoelectric conductors and the amplitude coefft. dependent upon the dosage of the X-ray exposure. The video values are decreased for the purpose of correcting the discharge generated by the respective exposures by as much as the values which are proportional to the video values and are proportional to the time difference between the scanning time and the reference time which is the exposure time, thereby, the formation of the artifacts by the self-discharge is lessened.