Rutherford Petawatt Laser to Explore New Areas of Physics

Optical Surfaces Ltd. has delivered an extremely high quality F0.8 on-axis parabola of 175mm diameter to the Central Laser Facility at the STFC Rutherford Appleton Laboratory.

Due to be installed on the Astra Gemini laser beam line the diffraction limited on-axis mirror will be used to focus the beam line energy to produce a maximum focused intensity of c. 1022 Wcm-2 enabling researchers to explore new areas of physics.

Using proprietary production techniques - Optical Surfaces highly experienced and skilled production team produced the fast focusing on-axis parabolic mirror with a surface accuracy of better than lambda/10 P-V and smoothness of 20/10 scratch/dig. The excellent surface quality achieved during manufacturing together with the exceptional high reflectivity coatings will enable RAL researchers to achieve the high optical performance and efficiency required by their ground breaking experiments. The optics were manufactured in Zerodur and coated using a special type high performance UV-Silver coating suitable for high reflectivity (R>98%) throughout the wavelength range between 350-800nm.

Peta Foster, Astro Gemini Link Scientist, commented “Our primary aim is the production of the highest intensity ever produced with a laser. This optic was extremely demanding in specification and we are delighted to take receipt of it. The focus of this optic should deliver a 5x increase in laser intensity that we hope will enable the study of an exciting new regime in laser-matter interactions”.

Dr Aris Kouris of Optical Surfaces Ltd commented We were delighted to have again been selected by a world-class laser facility to produce optics key to their future research. In this project the great challenge was to achieve the targeted surface accuracy and local gradients simultaneously for such a highly aspheric mirror (0.4mm of asphericity) and of this size. The higher the asphericity and the smaller the size of the optic the more difficult is to control both optical performance parameters but especially the local gradients. This is due to the fact that the gradients are changing directions very rapidly over a short distance making it extremely challenging to achieve. Optical performance at that level requires mastering of technical and practical aspects at multiple levels.

Optical Surfaces Ltd (www.optisurf.com) has been producing optical components and systems for more than 45 years and is now accepted as one of the world's leading manufacturers of high-precision optics for high power laser research facilities. The company's ISO 9001-2000 approved manufacturing workshops and test facilities are deep underground in a series of tunnels excavated in solid chalk where temperature remains constant and vibration is practically non-existent. With such stable conditions testing, particularly with long path lengths, becomes quantifiable and reliable. Working with these natural advantages is a highly skilled team of craftsmen with a commitment to excellence in both product quality and customer service.