Patent Number: 
Section: claims

1. A radiographic projector for housing a radioisotope, the apparatus comprising:a first radiation shield for housing a radioisotope;a second radiation shield;the first radiation shield defining a surface for removably receiving in surface-to-surface contact the second radiation shield;a connector for connecting said first radiation shield to said second radiation shield;wherein a first portion of said surface defines an aperture through which a radioisotope located in the first radiation shield may be projected out of the first radiation shield; anda second portion of said surface is inclined relative to a plane of said aperture. 2. A radiographic projector according to claim 1, wherein said second portion surrounds said first portion. 3. A radiographic projector according to claim 1, wherein said first radiation shield comprises a channel along which a radioisotope may be moved, said channel being in communication with said aperture. 4. A radiographic projector according to claim 3, wherein said first portion is substantially orthogonal to said channel. 5. A radiographic projector according to claim 1, wherein said first portion of said surface is located at an end of said first radiation shield, and said second portion of said surface is a chamfered edge of said first radiation shield. 6. A radiographic projector according to claim 1, wherein said surface of said first radiation shield is formed of a radiation absorbent material. 7. A radiographic projector according to claim 6, wherein said radiation absorbent material comprises at least one of depleted uranium, tungsten, lead, or tungsten powder in a binder. 8. A radiographic projector according to claim 1, further comprising a second radiation shield, adapted to removably engage said surface of said first radiation shield. 9. A radiographic projector according to claim 8, wherein said second radiation shield is a collimator. 10. A radiographic projector according to claim 8, wherein said second radiation shield is a guide tube. 11. A radiographic projector for housing a radioisotope, the radiographic projector comprising:a first radiation shield for housing a radioisotope;a second radiation shield;the first radiation shield defining a surface for removably engaging in surface-to-surface contact said second radiation shield;a connector for connecting said first radiation shield to said second radiation shield;wherein a first portion of said surface defines an aperture through which a radioisotope located in the first radiation shield may be projected out of the first radiation shield; andsaid surface of said first radiation shield comprises a radiation absorbent material. 12. A radiographic projector according to claim 11, wherein said radiation absorbent material comprises tungsten. 13. A radiographic projector according to claim 11, wherein said radiation absorbent material comprises tungsten powder in a less dense material matrix. 14. A radiographic projector as claimed in claim 3, further comprising a source holder assembly in which a radioisotope may be moved along said channel, wherein at least parts of said source holder assembly comprise a shielding material for shielding radiation emitted by said radioisotope in forward and backward directions along said channel. 15. A radiographic projector according to claim 11, wherein said first radiation shield comprises a channel along which a radioisotope may be moved, said channel being in communication with said aperture; andfurther comprising a source holder assembly in which a radioisotope may be moved along said channel, wherein at least parts of said source holder assembly comprise a shielding material for shielding radiation emitted by said radioisotope in forward and backward directions along said channel.