Patent Number: 
Section: claims

1. An optical system, comprising:a Bragg reflector configured to diffract incident light having a wavelength between about 0.1 nm and about 0.7 nm; anda diffraction grating comprising parallel lines engraved on a surface of the Bragg reflector, wherein the diffraction grating is configured to diffract incident light having a wavelength between about 0.6 nm and about 150 nm. 2. The optical system of claim 1, wherein the Bragg reflector comprises a crystal. 3. The optical system of claim 2, wherein the crystal comprises a silicon monocrystal. 4. The optical system of claim 2, further comprising a metallic layer which covers the diffraction grating. 5. The optical system of claim 1, further comprising a metallic layer which covers the diffraction grating. 6. An optical measuring device, comprising: an optical system, comprising:a Bragg reflector configured to diffract incident light having a wavelength between about 0.1 nm and about 0.7 nm; anda diffraction grating comprising parallel lines engraved on a surface of the Bragg reflector, wherein the diffraction grating is configured to diffract incident light having a wavelength between about 0.6 nm and about 150 nm;means for emitting at least one incident light beam toward the surface of the diffraction grating, the at least one incident light beam having a wavelength between about 0.1 nm and about 150 nm;means for collecting at least one returned light beam from the surface of the optical system; andmeans for rotating the optical system with respect to the at least one incident light beam so that the returned light beam results from the diffraction of the at least one incident light beam by the optical system. 7. The optical measuring device of claim 6, wherein the Bragg reflector comprises a crystal. 8. The optical measuring device of claim 7, wherein the crystal comprises a silicon monocrystal. 9. The optical measuring device of claim 7, wherein the optical system further comprises a metallic layer which covers the diffraction grating. 10. The optical measuring device of claim 6, wherein the optical system further comprises a metallic layer which covers the diffraction grating. 11. The optical measuring device of claim 6, wherein the means emitting emits a polychromatic light. 12. A light diffraction optical method using an optical measuring device, wherein the optical medical device comprises: an optical system, comprising: a Bragg reflector configured to diffract incident light having a wavelength between about 0.1 nm and about 0.7 nm; and a diffraction grating comprising parallel lines engraved on a surface of the Bragg reflector, wherein the surface of the Bragg reflector defines a normal axis, and the diffraction grating is configured to diffract incident light having a wavelength between about 0.6 nm and about 150 nm; means for emitting at least one incident light beam toward a surface of the diffraction grating, the at least one incident light beam having a wavelength between about 0.1 nm and about 150 nm; means for collecting at least one returned light beam from the surface of the optical system; and means for rotating the optical system with respect to the at least one incident light beam so that the returned light beam results from the diffraction of the at least one incident light beam by the optical system, the method comprising the steps of:emitting the at least one incident light beam in a direction of incidence forming an angle of incidence relative to the normal axis; andcollecting the at least one returned beam from the optical system in a returned direction forming a return angle with respect to the normal axis. 13. The method of claim 12, wherein the angle of incidence is between about 5° and about 80° when the wavelength of the at least one incident light beam is between about 0.1 nm and about 0.7 nm, and wherein the angle of incidence is at least about 70° when the wavelength of the at least one incident light beam is between about 0.6 nm and about 150 nm. 14. An optical system, comprising:a Bragg reflector configured to diffract incident light having a wavelength between 0.1 nm and 0.6 nm; anda diffraction grating comprising parallel lines engraved on a surface of the Bragg reflector, wherein the diffraction grating is configured to diffract incident light having a wavelength that is greater than 0.6 nm and is less than or equal to about 150 nm.