Large quantities of low cost hydrogen free of carbon oxides are required as fuel for the hydrogen economy. The photodetector comprises an integrated circuit and at least two optically sensitive layers. The electromagnetic signal measuring device is able to determine the intensity and polarization of the electromagnetic signal. Because the execution time is constant, the execution is deterministic and therefore may be used in applications requiring deterministic behavior. According to one embodiment is a safety scalpel system including handle capable of coupling to a blade with or without a safety housing. Light from luminescent lamp 10 travels into light guide plate 2 through incidence face 3, being emitted from emission face 4 for irradiating LCD panel 5.