The invention provides a radiation detector that can efficiently cool
solid-state sensors used in collecting photons produced during conversion
of radiation to light. The radiation detector can achieve an excellent
cooling effect by transferring heat, which is produced during the cooling
process, through a housing. The radiation detector comprises of an
detection unit that detects the photons produced during the conversion of
radiation to light, by utilizing a plurality of solid-state sensors
installed on the motherboard. The radiation detector further comprises a
heat transferring unit that cools the plurality of solid-state sensors
simultaneously.