An Evaluation of a Thin Film X-Ray Imaging Sensor with Laser Read-Out

Abstract

This report describes the industrial research work done during the summer of 1986. The main objective of this research was to develop a high resolution X-ray imaging system for mammographic applications. The basic set up of such system is quite simple: it consists of an x-ray tube; an x-ray sensor (which is coupled to the read out electronics), and the optical scanner assembly which serves as the reading device. Based on the feasibility studies carried out two years ago, much of the work during the past summer was targeted to improve the existing prototype, and to test out the new x-ray sensors. A new optical assembly was built for this system, which was used to examine the optical resolution of the new sensors. Experimental results were analysed using calculations of the resolution (MTF) of the sensors, and the results indicate that the latest sensors are capable of resolving a 1mm diameter object. Unfortunately, due to the limitation of time, no x-ray exposure test were done on test targets. However, a theoretical model describing the x-ray sensors responses to x-ray radiation and laser light (based on previous work carried out by A. Zermeno et al, 1979) is presented here. Also, the results of the research work, carried out since the feasibility study up until the end of the summer of 1986, indicate that the sensors have a great potential for achieving limiting resolutions in the range of "0.1mm" objects.