Absorber for terahertz radiation management

Patent · Tue Dec 08 00:00:00 EST 2015

OSTI ID:1230013

Biallas, George Herman; Apeldoorn, Cornelis; Williams, Gwyn P.; Benson, Stephen V.; Shinn, Michelle D.; Heckman, John D.

A method and apparatus for minimizing the degradation of power in a free electron laser (FEL) generating terahertz (THz) radiation. The method includes inserting an absorber ring in the FEL beam path for absorbing any irregular THz radiation and thus minimizes the degradation of downstream optics and the resulting degradation of the FEL output power. The absorber ring includes an upstream side, a downstream side, and a plurality of wedges spaced radially around the absorber ring. The wedges form a scallop-like feature on the innermost edges of the absorber ring that acts as an apodizer, stopping diffractive focusing of the THz radiation that is not intercepted by the absorber. Spacing between the scallop-like features and the shape of the features approximates the Bartlett apodization function. The absorber ring provides a smooth intensity distribution, rather than one that is peaked on-center, thereby eliminating minor distortion downstream of the absorber.

• Research Organization: Thomas Jefferson National Accelerator Facility (TJNAF), Newport News, VA (United States)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-06OR23177
• Assignee: JEFFERSON SCIENCE ASSOCIATES, LLC
• Patent Number(s): 9,209,587
• Application Number: 14/662,322
• OSTI ID: 1230013
• Resource Relation: Patent File Date: 2015 Mar 19
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
61 RADIATION PROTECTION AND DOSIMETRY