Patent Number: 
Section: claims

1. A variable pin-hole type collimator applied to a radiation imaging device comprising:a hole forming module having a plurality of apertures which are stacked in a direction of irradiation such that each aperture defines a penetrating-space through which radiation passes;a plurality of driving modules which are configured such that each driving module varies each penetrating-space of the aperture independently; anda collimating controller to control the driving modules such that each penetrating-space of the aperture varies independently and the hole forming module forms a pin-hole, which is divided into a first cone region, a penetrating hole region and a second cone region, through which radiation passes. 2. The variable pin-hole type collimator according to claim 1, wherein the penetrating-space formed by each aperture has a circular shape or an oval shape. 3. The variable pin-hole type collimator according to claim 1, wherein each aperture is made from a radiation-shielding material. 4. A radiation imaging device to which a variable pin-hole type collimator according to claim 1 is applied.