Characterization Of Veiling Glare In Angiographic Systems

This investigation concerns the sources and the characteristics (importance and structure) of veiling glare in angiographic systems. The veiling glare is modelled by empirical PSFs. The parameters of these PSFs are fitted from contrast ratio measurements. Various acquisition configurations are examined. Theoretical expressions have been developed to study the spatial variance of the PSFs and the contribution of the image intensifier (II) input screen in the global veiling glare. The results are both qualitative and quantitative. The spread of the veiling glare is well modelled by the sum of short and long distance terms. The importance of the II input screen is shown and is related to both short and long range effects.