Patent Number: 
Section: claims

1. An intensifying screen for exposing X-ray film, the intensifying screen comprising:a screen support backing;a luminescent layer including a luminescent material that emits light in the presence of X-rays;a reflective layer disposed between the luminescent layer and the screen support backing, the reflective layer including a plurality of micro-prisms that reflect light emitted by the luminescent material,wherein micro-prism surfaces of the plurality of micro-prisms do not reflect light that impinges on the respective micro-prism surfaces at an angle exceeding a critical angle as measured from the respective micro-prism surfaces. 2. The intensifying screen according to claim 1, wherein the reflective layer is configured to reflect light emitted by the luminescent material toward an X-ray film disposed adjacent to the luminescent layer. 3. The intensifying screen according to claim 1, wherein the reflective layer reflects light in a direction generally perpendicular to a surface of the screen support backing facing the reflective layer. 4. The intensifying screen according to claim 1, wherein the reflective layer reflects light in a direction generally perpendicular to a surface of the luminescent layer facing the reflective layer. 5. The intensifying screen according to claim 1, wherein the luminescent layer emits visible light in response to excitation by X-rays. 6. The intensifying screen according to claim 1, wherein the luminescent material comprises a phosphor material. 7. The intensifying screen according to claim 1, wherein the reflective layer comprises a polymer material. 8. The intensifying screen according to claim 1, wherein the reflective layer comprises a crystalline material. 9. The intensifying screen according to claim 1, wherein the reflective layer comprises a glass material. 10. The intensifying screen according to claim 1, further comprising a light-absorbing layer on a side of the plurality of micro-prisms opposite the luminescent layer. 11. The intensifying screen according to claim 1, wherein the screen support backing comprises a light-absorbing layer. 12. An X-ray film cassette comprising:at least one intensifying screen according to claim 1;a housing surrounding the at least one intensifying screen. 13. The X-ray film cassette according to claim 12, wherein the X-ray film cassette includes two intensifying screens disposed on opposing inner surfaces of the housing. 14. An X-ray film assembly comprising:at least one intensifying screen according to claim 1;an X-ray film. 15. The X-ray film assembly according to claim 14, wherein the X-ray film is disposed between two intensifying screens. 16. The X-ray film assembly according to claim 14, wherein the X-ray film has an emulsion layer. 17. The intensifying screen according to claim 1, wherein the micro-prism surfaces reflect light that impinges on the respective micro-prism surfaces at an angle that is less than the critical angle as measured from the respective micro-prism surfaces. 18. The intensifying screen according to claim 1, wherein the micro-prism surfaces reflect light that impinges on the respective micro-prism surfaces at an angle that is less than the critical angle as measured from the respective micro-prism surfaces. 19. The intensifying screen according to claim 1, wherein light impinging on the micro-prism surfaces that is not reflected is refracted and passes through at least a portion of the reflective layer.