Patent Number: 
Section: claims

1. An amplifying optical cavity of the FABRY-PEROT type for producing monochromatic X-rays through a COMPTON reaction of a high-rate picoseconds pulsed laser beam with a synchronized electron beam, the cavity comprising a closed enclosure operably being vacuumed, traversed by an electron beam tube, the enclosure comprising a laser, at least a first actuator operably maintaining and positioning two plane optical reflectors, and at least a second actuator operably maintaining and positioning two spherical optical reflectors operably focusing the laser beam at a point of interaction with the electron beam, wherein the optical reflectors are arranged by the first and second actuators such that the optical reflectors substantially define the vertexes of a tetrahedron. 2. An amplifying optical cavity according to claim 1, wherein the spherical optical reflectors second actuator has two complementary clearances, arranged so as to define a bay for the passage of the electron beam tube. 3. An amplifying optical cavity according to claim 1, wherein at least one of the actuators comprise an orienting member for orienting the associated reflector made from a single mechanical piece, including at least three distinct portions, movable with respect to each other, by flexible hinges. 4. An amplifying optical cavity according to claim 3, wherein the three distinct portions of the orienting member are movable around two rotation axes converging at one point substantially confounded with the optical center of the reflector. 5. An amplifying optical cavity according to claim 1, wherein at least one of the actuators is actuated by linear electric motors encapsulated within a sealed enclosure made of stainless steel and extended by a bellows. 6. An amplifying optical cavity according to claim 5, wherein the linear electric motors are kept in permanent contact with respect to the at least one actuator by a spring element which generates a return force. 7. An amplifying optical cavity according to claim 1, wherein at least one of the actuators has a Z-axis translation table, the translation table supporting two linear electric motors capable of actuating the reflector orienting member. 8. An amplifying optical cavity according to claim 1, wherein at least one of the actuators has a piezoelectric actuator oriented along the direction of the reflector optical axis and maintained in position by a spring ring. 9. An amplifying optical cavity according to claim 1, wherein all of the actuators are positioned on a main support, the main support being the only piece contacting the closed enclosure. 10. A system for producing monochromatic X-rays through a COMPTON reaction, comprising an amplifying, FABRY-PEROT optical cavity comprising a high-rate picoseconds pulsed laser beam with a synchronized electron beam, the cavity comprising a closed enclosure operably being vacuumed, traversed by an electron beam tube, the enclosure comprising a laser, at least a first actuator operably maintaining and positioning two plane optical reflectors, and at least a second actuator operably maintaining and positioning two spherical optical reflectors operably focusing the laser beam at a point of interaction with the electron beam, wherein the optical reflectors are arranged by the first and second actuators such that the optical reflectors substantially define the vertexes of a tetrahedron.