8 December 1997 New 1.053-um coating developments for the Megajoule laser: reduction of defect density on large optics
Author Affiliations +
Proceedings Volume 3047, Solid State Lasers for Application to Inertial Confinement Fusion: Second Annual International Conference; (1997) https://doi.org/10.1117/12.294281
Event: Second International Conference on Solid State Lasers for Application to ICF, 1996, Paris, France
Abstract
The manufacture of modern optical components requires the use of high performance interferometers, usually based on phase-shifting techniques. However, there is currently no commercial phase-shifting interferometer having the capacity to measure large parts, such as those found in Inertial Confinement Fusion Lasers (NIF and Méga-Joule), and other large systems. Standard interferometers lack the simultaneous qualities of accuracy and spatial resolution required for the measurement of such components. Indeed, it has been shown that surface ripples with wavelengths of around 1 to 10 millimeters are extremely dangerous for large ICF optics, even at low amplitude, because of the process of non-linear ripple amplification present in high power laser systems. In order to circumvent the restrictions on size and performance of standard interferometers, we have designed and built a scanning interferometer, using a standard "small" diameter phase shifting interferometer. A PC computer is used to control the measurement process, acquire the interferograms and stitch the measurements together to produce the original large surface. The measurement sequence is completely automated. The advantages ofthis technique are low cost, small size, and no loss ofspatial resolution. One system has been in actual use for the characterization of large size mirrors (approx. 400 x 600 mm) since december 1994. In this presentation, we shall look over the design of the system, produce actual measurements, and discuss the technical implications of the stitching process in relation to specifications such as those currently being derived for ICF large components. This work is supported by CEA/CEL-V, as part of the Laser MégaJoule Program.
© (1997) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Odile Lam, Odile Lam, Andre Roussel, Andre Roussel, Anne Fornier, Anne Fornier, Bernard Geenen, Bernard Geenen, Herve Leplan, Herve Leplan, B. Pinot, B. Pinot, W. Alexandre, W. Alexandre, P. Pally, P. Pally, } "New 1.053-um coating developments for the Megajoule laser: reduction of defect density on large optics", Proc. SPIE 3047, Solid State Lasers for Application to Inertial Confinement Fusion: Second Annual International Conference, (8 December 1997); doi: 10.1117/12.294281; https://doi.org/10.1117/12.294281
PROCEEDINGS
12 PAGES


SHARE
Back to Top