Theoretical and experimental determination of sensitivity and edge enhancement in xeroradiography and ionography.

A study of the factors affecting image quality and x-ray sensitivity of ionography and xeroradiography is presented. First, the relative charge sensitivities (nC/cm2mR) are compared. It is shown that high pressure xenon (10 atm cm) as used in ionography produces more than 2.5--3.5 times more charge than the selenium layers used in xeroradiography for the same x-ray exposure. The influence of development time and toner deposition on the appearance of images is investigated theoretically and experimentally. A parameter describing development sensitivity is proposed. It is shown that an increase in development sensitivity (ODcm2/nC) with increasing development time is accompanied by a loss in edge enhancement. The development sensitivity of ionography is about twice that typical of xeroradiography. This makes the total sensitivity (OD/mR) or the ionography process more than 4.5--6.5 times that of xeroradiography. The total sensitivity of ionography is about 1/2 that of par speed film screen combinations.