Relative to CRT monitors, FPDs have the following advantages:
FPDs are, on average, brighter than CRTs. A typical CRT might have brightness of about 100 candelas/square meter, a unit of measurement referred to as a nit. (Some monitors are rated in foot Lamberts (fL), where one fL equals about 3.43 nits.) A high-quality 15-inch FPD might be rated at 300 nits, three times as bright as a typical CRT. This brightness disparity decreases a bit in larger sizes. For example, a high-quality 19-inch FPD might be rated at 235 nits. CRTs dim as they age, although a brightness control with enough range at the upper end can often be used to set an old CRT to near-original brightness. The cold cathode ray tubes (CCRTs) used to backlight FPDs also dim as they age, but generally fail completely before reduced brightness becomes a major issue.
Contrast measures the difference in luminance between the brightest and dimmest portions of an image, and is expressed as a ratio. The ability to display a high-contrast image is an important aspect of image quality, particularly for text. An average CRT monitor may have a contrast ratio of 200:1, and a superb CRT 250:1. An inexpensive FPD may have a contrast ratio of 200:1, and a superb FPD 500:1. In other words, even an inexpensive FPD may have a better contrast ratio than an excellent CRT monitor.
Even good flat-screen CRTs are subject to objectionable reflections when used in bright environments, ...