The present invention generally relates to the field of testing computing devices. A first light is emitted from a first scintillator by the ray transmitted through the light shielding film. The front wall and side walls have lower portions surrounding the exhaust aperture on three sides, upper ends defining a generally rectangular open end disposed in an angular plane with respect to a vertical axis, and interior surfaces forming an arcuate extension of the exhaust aperture. The bone member may be coupled to the base generally parallel to the surface of the base.