No abstract

No abstract

Commercially available diamond turning machines offer high levels of accuracy where the full potential of the machine is realised. Unfortunately, surface form accuracy and roughness are dependent on the limiting stiffness of the machine / workpiece environment. Vacuum chuck methods offer a high degree of stiffness combined with the opportunity of mounting substrates in a stress free manner. Thin substrates (4 -12 mm) are relatively easily stressed and the application of vacuum chuck mounting for such components, present many problems. These include deformations due to internal material stress, vibration, and the print -through effect.We have measured the reproducability of deformations caused by the print -through effect and have developed techniques for its elimination. The feasibility of using this print -through mechanism for machining non -rotationally symmetric forms is also discussed. ABSTRACTCommercially available diamond turning machines offer high levels of accuracy where the full potential of the machine is realised. Unfortunately, surface form accuracy and roughness are dependent on the limiting stiffness of the machine/workpiece environment. Vacuum chuck methods offer a high degree of stiffness combined with the opportunity of mounting substrates in a stress free manner. Thin substrates (4-12 mm) are relatively easily stressed and the application of vacuum chuck mounting for such components, present many problems. These include deformations due to internal material stress, vibration, and the print-through effect.We have measured the reproducability of deformations caused by the print-through effect and have developed techniques for its elimination. The feasibility of using this print-through mechanism for machining non-rotationally symmetric forms is also discussed.

Traditional focusing optics for IR lasers are refractive lenses and off-axis reflective mirrors. ZnSe meniscus and plano-convex lenses dominate the refractive lens types in use today for CO 2 laser cutting, welding, marking, and engraving systems, to name a few of the more common applications. Silicon and copper spherical mirrors that are used near normal incidence and off-axis copper parabolic mirrors dominate the type of reflective mirrors used in veryhigh-power CO 2 lasers for welding and heat treating. These types of mirrors are made with common polishing and diamond-turning techniques that are well known. In the last three years, advances in fabrication techniques have allowed optic manufacturers to produce more advanced optical surfaces on metal and refractive materials. This paper will provide details of some of these novel focusing optics for IR laser applications. The paper will include design details of ring-focus off-axis parabolas, focused flat-top generators, toroidal lenses and mirrors, faceted integrators, and long-radius off-axis parabolas. Both design and theoretical performance will be given for the optics. In some cases, laser test data will also be provided.

No abstract