Patent Number: 
Section: claims

1. A laser scanning microscope, comprising: a light source, in particular a laser light source defining a light beam,  an interruption device ( 1 ) for the light beam ( 2 ),  and means ( 3 ) for monitoring the functioning of the interruption device ( 1 ) being associated with the interruption device ( 1 ) wherein the means ( 3 ) are configured to monitor the interruption state generated by the interruption device ( 1 ). 2. The laser scanning microscope as defined in  claim 1 , wherein an optical and/or acoustic indication is provided for indicating the position of the interruption device ( 1 ) in or out of the light beam ( 2 ). claim 1 3. The laser scanning microscope as defined in  claim 1 , wherein the means ( 3 ) for monitoring have a light barrier and the interruption device ( 1 ) has an opening ( 4 ) formed therein. claim 1 4. The laser scanning microscope as defined in  claim 1  wherein the means for monitoring have an electrical switch, preferably an interrupter contact. claim 1 5. The laser scanning microscope as defined in  claim 1 , wherein the means for monitoring have an analysis unit with which at least one safety device is activatable. claim 1 6. The laser scanning microscope as defined in  claim 5 , wherein a signal is transmittable to the light source and/or to a further interruption device by the analysis unit and/or the safety device. claim 5 7. The laser scanning microscope as defined in  claim 6 , wherein a delay device is provided in terms of activation of the safety device and/or transmission of the signal. claim 6 8. The laser scanning microscope as defined in  claim 6 , wherein an indication of a malfunction of the interruption device and/or of an activation of the safety device is provided. claim 6 9. The laser scanning microscope as defined in  claim 1 , wherein the interruption device ( 1 ) has a mechanical shutter ( 5 ). claim 1 10. The laser scanning microscope as defined in  claim 1 , wherein the interruption device ( 1 ) has at least two movable components ( 6 ,  7 ) which are configured and arranged so that the mechanical momentum generated by at least one moving component ( 6 ) is compensated for by the motion of the at least another component ( 7 ). claim 1 11. The laser scanning microscope as defined in  claim 10 , wherein the components ( 6 ,  7 ) have the same mass. claim 10 12. The laser scanning microscope as defined in claims  10 , wherein at least one component is a counterweight. 13. A shutter ( 5 ), used in an optical system, comprising: a light beam ( 2 ) of a laser light source, and  at least two movable components ( 6 ,  7 ) being configured and arranged so that the mechanical momentum generated by at least one moving component ( 6 ) is compensated for by the motion of at least another component ( 7 ). 14. The shutter ( 5 ) as defined in  claim 13 , wherein the components ( 6 ,  7 ) are of identical or mirror-symmetrical configuration. claim 13 15. The shutter ( 5 ) as defined in  claim 13 , wherein the components ( 6 ,  7 ) have the same mass. claim 13 16. The shutter ( 5 ) as defined in  claim 13 , wherein at least one component is a counterweight. claim 13 17. The shutter ( 5 ) as defined in  claim 13 , wherein the components ( 6 ,  7 ) are arranged for straight-line and/or rotational motion. claim 13 18. The shutter ( 5 ) as defined in  claim 13 , wherein the components ( 6 ,  7 ) are arranged for oppositely directed motion. claim 13 19. The shutter ( 5 ) as defined in  claim 13 , wherein at least one component ( 6 ,  7 ) is configured as a barrier or rocker. claim 13 20. The shutter ( 5 ) as defined in  claim 19 , wherein two barriers or rockers are provided. claim 19 21. The shutter ( 5 ) as defined in  claim 13 , wherein at least one component ( 6 ,  7 ) has an opening ( 8 ) for the light beam ( 2 ). claim 13 22. The shutter ( 5 ) as defined in  claim 13 , wherein the components ( 6 ,  7 ) are movable by a motion device which converts an electrical signal into a mechanical motion. claim 13 23. The shutter ( 5 ) as defined in  claim 22 , wherein the motion device has an electromagnet ( 9 ). claim 22 24. The shutter ( 5 ) as defined in  claim 13 , wherein means ( 3 ) for monitoring the interruption state of the light beam ( 2 ) generated by the shutter ( 5 ) are associated with the shutter ( 5 ). claim 13 25. The shutter ( 5 ) as defined in  claim 13 , wherein an optical and/or acoustic indication is provided for indicating the position of the interruption device ( 1 ) in or out of the light beam ( 2 ). claim 13 26. A shutter system for an optical system comprising a light source, said light source adapted to transmit light along a light beam path; said shutter system comprising at least two movable shutter components; said shutter components operatively arranged to intersect said light beam path and configured such that the mechanical momentum generated by at least one moving shutter component is compensated by the motion of at least another shutter component. 27. The shutter system of  claim 26  further comprising monitoring means; said monitoring means operatively arranged to monitor the intersection state of said shutter components. claim 26