The temperature gradients in a side-cooled mirror would create a thermal bending moment along the mirror length. For a slender side-cooled mirror with longitudinally uniform incident beam, the tangential slope error is primarily due to the bowing deformation caused by this thermal bending moment. The thermal bending moment depends on the temperature distribution, which is a function of the mirror geometry, heat load, and cooling design. Optimal design of a side-cooled mirror can achieve a “favorable” temperature profile to make the thermal bending moment, with respect to the substrate neutral plane, approach zero, so that the bowing deformation of the mirror is minimized. To understand the deformation of a side-cooled mirror and achieve an optimal design, a theoretical formulation is developed.

Date Published: 18 October 2004
PDF: 6 pages
Proc. SPIE 5533, Advances in Mirror Technology for X-Ray, EUV Lithography, Laser, and Other Applications II, (18 October 2004); doi: 10.1117/12.561435

Published in SPIE Proceedings Vol. 5533:
Advances in Mirror Technology for X-Ray, EUV Lithography, Laser, and Other Applications II
Ali M. Khounsary; Udo Dinger; Kazuya Ota, Editor(s)