Patent ID: 7430280

Claim:
A radiation emitting device comprising: a radiation emitter configured for emitting X-rays; an emitter switch, the radiation emitter being secured to the emitter switch; a disk-shaped collimator, the collimator having a central axial through-hole portion and a plurality of radial apertures configured for collimating the X-rays emitted from the radiation emitter into pencil beams, the through-hole portion receiving the radiation emitter and the emitter switch therein; a rotating mechanism coupled to the through-hole portion of the collimator for rotating the collimator; an annular shielding enclosure having an opening configured for allowing the pencil beams to exit therethrough, wherein the shielding enclosure encloses the collimator, the radiation emitter and the emitter switch therein; wherein the radiation emitter is jointly and axially movable with respect to the emitter switch in the through-hole portion between an off position and an on position, wherein in the off position, the radiation emitter is misaligned with any one of the radial apertures thus ensuring the X-rays emitted from the radiation emitter blocked by the shielding enclosure, and wherein in the on position, the radiation emitter is aligned with one of the radial apertures therefore ensuring the X-rays emitted from the radiation emitter exit from the opening of the shielding enclosure.