What effect does continuous exposure to bright daylight have on a zinc cadmium sulfide fluoroscopic screen?

Continuous exposure to bright daylight on a zinc cadmium sulfide fluoroscopic screen results in discoloration and a loss of brilliance due to photochemical reactions that occur when the screen is exposed to bright light for extended periods. Zinc cadmium sulfide is sensitive to light, and when subjected to intense daylight, the phosphorescent material can degrade or alter its chemical composition. This degradation leads to reduced fluorescence efficiency, thereby diminishing the brightness of the screen in subsequent use.

In contrast, the other options suggest effects that are either enhancement or neutrality regarding the screen's condition under bright daylight, which do not align with the material properties and behavior of zinc cadmium sulfide when exposed to such conditions. The correct understanding of how this type of screen reacts to light is crucial in ensuring proper usage and longevity of the screen in radiographic applications.