Patent Number: 
Section: claims

1. An extreme ultraviolet light source apparatus for supplying extreme ultraviolet light to a processing unit for performing processing by using the extreme ultraviolet light, said apparatus comprising:a chamber in which the extreme ultraviolet light to be supplied to said processing unit is generated;a collector mirror provided in said chamber, and configured to collect the extreme ultraviolet light generated in said chamber and to output the extreme ultraviolet light from said chamber; andan optical path connection module arranged at a position between said chamber and said processing unit, and configured to be detachable from the position by detaching said chamber from said processing unit, to isolate a route of the extreme ultraviolet light between said chamber and said processing unit from outside, and to form, in the optical path connection module, an intermediate focusing point of the extreme ultraviolet light from said chamber, whereinsaid optical path connection module includes a wave-shaped section formed on an inner wall of said optical path connection module. 2. An extreme ultraviolet light source apparatus according to claim 1, further comprising:a first gate valve being provided in a connecting part of said chamber to said optical path connection module. 3. An extreme ultraviolet light source apparatus according to claim 1, further comprising:a second gate valve being provided in a connecting part of said processing unit to said optical path connection module. 4. An extreme ultraviolet light source apparatus according to claim 1, further comprising:a third gate valve being provided at one end of said optical path connection module to be connected to said chamber. 5. An extreme ultraviolet light source apparatus according to claim 1, further comprising:a fourth gate valve being provided at one end of said optical path connection module to be connected to said processing unit.