In nuclear imaging, when a gamma ray strikes a scintillator, a burst of visible light is created. That light is detected by a photodetector and processed by downstream electronics. It is desirable to harness as much of the burst of light as possible and get it to the photodetector. In a detector element (18), a first reflective layer (44) partially envelops a scintillation crystal (34). The first reflective layer (44) diffuses the scintillated light. A second reflective layer (46) and a support component reflective layer (48) prevent the light from leaving the scintillation crystal (34) by any route except a light emitting face (36) of the scintillator (34). In another embodiment, a light concentrator (50) is coupled to the scintillator (34) and channels the diffuse light onto a light sensitive portion of a photodetector (38). The reflective layers (44, 46, 48) and the concentrator (50) ensure that all or nearly all of the light emitted by the scintillator (34) is received by the photodetector (38).