Embedded medical and space systems make use of miniaturized computers that are designed and programmed to do only one or a very limited number of functions. Their minute size and very low energy demands allow them to be used in several environments. Combined with other systems, they can be used to create any number of new devices. Embedded Systems in Medicine Because of their small size and their specificity in function, embedded systems have been widely used in medicine, especially when used as a relatively large component. Current computer tomography (CT) scanners use application-specific integrated circuits (ASICs) that span a few square inches; this is quite big in comparison to other implementations of embedded systems which cover a mere fraction of an inch. Photodiodes are yet another embedded system that is critical to CT scanners. Photodiode arrays (photodiodes arranged in a linear fashion on an integrated chip) are responsible for detecting different wavelengths of light, a fundamental function in CT technology.