An apparatus directing x-rays along a predetermined axis includes an x-ray optic having one or more nested x-ray reflector rings positioned relative to a source generating broad spectrum x-rays so that generated x-rays moving away from the predetermined axis are collected by the reflector incident at or close to a Bragg angle to thereby reflect the collected x-rays into a conically parallel beam. A first diffractor is positioned relative to the x-ray optic to receive incident thereon the conically parallel beam, the first diffractor selected from a truncated cone and a cylinder and diffracting the conically parallel beam toward the predetermined axis. A second diffractor is positioned relative to the first diffractor and having a geometry effective to receive incident thereon and redirect the conically parallel beam along the predetermined axis as a collimated beam of substantially parallel x-rays.