A New Class of Focusing Crystal Surfaces for the Bragg Spectroscopy of High-Density Plasmas and Small (Point-Like) X-Ray Sources

Web Published:

A new class of focusing crystal surfaces for the Bragg spectroscopy of high-density plasmas and small x-ray sources

Princeton Docket # 15-3175-1


Researchers at Princeton Plasma Physics Laboratory, Princeton University have identified a new class of crystal surfaces that makes it possible to maximize the photon throughput of a Bragg crystal spectrometer for a specified spectral range.

Currently, the x-ray Bragg spectroscopy of laser-produced high-density plasmas applies only standard crystal forms, such as flat crystals, spherically, cylindrically, or toroidally bent crystals and crystals of a logarithmic-spiral form, which offer very limited options for an optimization of the photon throughput in the desired spectral range. For instance, when log-spiral crystals are employed, the spectral range and photon throughput must be adapted to the given length of the crystal by varying the crystal’s position relative to the x-ray source - a method, which leads to focusing errors and a deterioration of the spectral resolution. This invention makes such compromises unnecessary. It describes a general class of new focusing crystal surfaces for the x-ray Bragg spectroscopy of (point-like) high-density plasmas that make it possible to optimize both spectral resolution and photon throughput for the desired spectral range and a given length of the crystal.



•       X-ray Bragg crystal spectrometers

•       Extreme Ultraviolet lithography

•       Military



•       Proper three-dimensional expansions of two-dimensional curves

•       Maximize the photon throughput for a specified spectral range


Princeton Plasma Physics Laboratory (PPPL)  

The U.S. Department of Energy’s Princeton Plasma Physics Laboratory (PPPL) is a collaborative national center for fusion energy research. The Laboratory advances the coupled fields of fusion energy and plasma physics research, and, with collaborators, is developing the scientific understanding and key innovations needed to realize fusion as an energy source for the world. An associated mission is providing the highest quality of scientific education.



Manfred Bitter is a Principal Research Physicist at the Princeton Plasma Physics Laboratory (PPPL) of Princeton University. He joined PPPL in 1977 after previous appointments at the European Space Organization in Frascati, Italy from 1969 to 1973 and the Centre des Recherches en Physique des Plasmas in Lausanne, Switzerland from 1973 to 1977. He was educated in Germany, where he received a diploma in physics (‘Diplom-Physiker’) from the Ludwig Maximilian Universität in Munich and a doctorate in physics (‘Dr. rer. nat.’) from the Technische Hochschule in Aachen. His fields of expertise are the physics of highly charged ions and x-ray spectroscopy of hot tokamak plasmas with a particular focus on Doppler measurements of the plasma ion temperatures and plasma flow velocities. For the purpose of these measurements, he invented a (1D) x-ray imaging crystal spectrometer, which provides radial profiles of these important plasma parameters with high spectral and high spatial resolutions. This type of spectrometer is now being used on tokamaks and stellarators worldwide and its design concept has also been adopted for measurements of the profiles of plasma ion-temperatures and plasma flow-velocity profiles in the International Thermonuclear Experimental Reactor (ITER). More recently, he and his colleagues at PPPL, Dr. Kenneth W. Hill and Dr. Phillip C. Efthimion, developed high-resolution spectrometers and 2D imaging systems for the diagnostics of laser-produced plasmas and applications in EUV lithography. Manfred Bitter is a fellow of the American Physical Society since 1985. He received the Alexander von Humboldt Award in 1996 and the Kaul Prize for Excellence in Plasma Physics in 2012.


Intellectual Property & Development status

Patent protection is pending.

Princeton is currently seeking commercial partners for the further development and commercialization of this opportunity.



Michael R. Tyerech

Princeton University Office of Technology Licensing • (609) 258-6762• tyerech@princeton.edu

Sangeeta Bafna

Princeton University Office of Technology Licensing • (609) 258-5579• sbafna@princeton.edu


Patent Information:
For Information, Contact:
Michael Tyerech
former Princeton Sr. Licensing Associate
Princeton University
Manfred Bitter
Kenneth Hill
Philip Efthimion
Luis Delgado-Aparicio
Novimir Pablant