Inductively-driven light source for microscopy
An apparatus for producing light includes a chamber that has a plasma discharge region and that contains an ionizable medium. The apparatus also includes a magnetic core that surrounds a portion of the plasma discharge region. The apparatus also includes a pulse power system for providing at least one pulse of energy to the magnetic core for delivering power to a plasma formed in the plasma discharge region. The plasma has a localized high intensity zone.
1. A microscopy system comprising:
a first optical element for collecting light
a second optical element for projecting an image of a sample onto a detector in optical communication with the first and second optical elements; and
a light source in optical communication with the first optical element comprising
i. a chamber having a plasma discharge region and containing an ionizable medium,
ii. a magnetic core that surrounds a portion of the plasma discharge region, and
iii. a pulse power system for providing at least one pulse of energy to the magnetic core for delivering power to a plasma formed in the plasma discharge region, wherein the plasma has a localized high intensity location.
2. The microscopy system of claim 1 wherein the first optical element collects light emitted by the light source to illuminate the sample and the second optical element projects an image of the sample onto the detector.
3. The microscopy system of claim 1 wherein the plasma substantially varies in current density along a path of current flow in the plasma.
4. The microscopy system of claim 1 wherein the zone is a point source of high intensity light.
5. The microscopy system of claim 1 wherein the zone is a region where the plasma is pinched to form a neck.
6. The microscopy system of claim 1 wherein a feature in the chamber creates the zone.
7. The microscopy system of claim 1 wherein gas pressure creates the zone.
8. The microscopy system of claim 1 wherein current flow in the plasma creates the zone.
9. The microscopy system of claim 6 wherein the feature is configured to substantially localize an emission of light by the plasma.
10. The microscopy system of claim 6 wherein the feature is located remotely relative to the magnetic core.
11. The microscopy system of claim 6 wherein the feature defines a necked region for localizing an emission of light by the plasma.
12. The microscopy system of claim 6 wherein the feature comprises a gas inlet.
13. The microscopy system of claim 6 wherein the feature comprises cooling capability.
14. The microscopy system of claim 1 wherein the at least one pulse of energy provided to the magnetic core forms the plasma.
15. The microscopy system of claim 1 wherein the pulse power system provides each pulse of energy at a frequency of between about 100 pulses per second and about 15,000 pulses per second.
16. The microscopy system of claim 1 wherein each pulse of energy is provided for a duration of time between about 10 ns and about 10 μs.
17. The microscopy system of claim 1 wherein the pulse power system comprises an energy storage device.
18. The microscopy system of claim 17 wherein the energy storage device comprises at least one capacitor.
19. The microscopy system of claim 1 wherein the pulse power system comprises a second magnetic core.
20. The microscopy system of claim 19 wherein the second magnetic core discharges each pulse of energy to the first magnetic core to deliver power to the plasma.
21. The microscopy system of claim 19 wherein inductive leakage current flowing from the second magnetic core to the magnetic core surrounding the portion of the plasma discharge region pre-ionizes the ionizable medium.
22. The microscopy system of claim 1 wherein the pulse power system comprises a magnetic compression pulse generator.
23. The microscopy system of claim 1 wherein the pulse power system comprises a magnetic switch for selectively delivering the pulse of energy to the magnetic core.
24. The microscopy system of claim 1 wherein the pulse power system comprises a saturable inductor.
25. The microscopy system of claim 1 wherein the magnetic core is configured to produce at least essentially a Z-pinch in a channel region located in the chamber.
26. The microscopy system of claim 1 wherein the magnetic core is configured to produce at least essentially a capillary discharge in a channel region located in the chamber.
27. The microscopy system of claim 1 further comprising at least one port for introducing the ionizable medium into the chamber.
28. The microscopy system of claim 1 wherein the ionizable medium is at least one or more gases selected from the group consisting of Xenon, Lithium, Tin, Nitrogen, Argon, Helium, Fluorine, Ammonia, Stannane, Krypton and Neon.
29. The microscopy system of claim 1 comprising an ionization source for pre-ionizing the ionizable medium.
30. The microscopy system of claim 29 wherein the ionization source is a source selected from the group consisting of an ultraviolet lamp, an RF source, a spark plug and a DC discharge source.
31. The microscopy system of claim 1 comprising an enclosure that at least partially encloses the magnetic core.
32. The microscopy system of claim 31 wherein the enclosure defines a plurality of holes.
33. The microscopy system of claim 32 wherein a plurality of plasma loops pass through the plurality of holes when the magnetic core delivers power to the plasma.
34. The microscopy system of claim 31 wherein the enclosure comprises two parallel plates.
35. The microscopy system of claim 34 wherein the parallel plates are conductive and form a primary winding around the core.
36. The microscopy system of claim 31 wherein coolant flows through the enclosure for cooling a location adjacent the localized high intensity zone.
37. The microscopy system of claim 31 wherein the enclosure comprises a material selected from the group consisting of copper, tungsten, aluminum and copper-tungsten alloys.
38. The microscopy system of claim 1 wherein the plasma forms the secondary of a transformer.
39. The microscopy system of claim 6 wherein the feature is at least one aperture in a rotating disk.
40. The microscopy system of claim 39 wherein a thin gas layer conducts heat from the disk to a cooled surface.
41. The microscopy system of claim 1 wherein the light source is configured to produce light at wavelengths shorter than about 100 nm when the light source generates a plasma discharge.
42. A microscopy method comprising:
introducing an ionizable medium capable of generating a plasma into a chamber;
applying at least one pulse of energy to a magnetic core that surrounds a portion of a plasma discharge region within the chamber such that the magnetic core delivers power to the plasma, wherein the plasma has a localized high intensity zone;
collecting light emitted by the plasma with a first optical element;
projecting the collected light through a sample; and
projecting the light emitted through the sample to a detector.
43. A microscopy system comprising:
a lens;
a detector in optical communication with the lens; and
a light source in optical communication with the lens comprising
i. a chamber having a plasma discharge region and containing an ionizable medium,
ii. a magnetic core that surrounds a portion of the plasma discharge region, and
iii. a means for providing at least one pulse of energy to the magnetic core for delivering power to a plasma formed in the plasma discharge region, wherein the plasma has a localized high intensity zone.