Hot Forming of Curved Mirrors Without the Need for a Mandrel

Background

Large format active or deformable mirrors can enable optical applications that are difficult to achieve with more conventional-sized deformable mirrors. In particular, adaptive secondary mirrors (ASMs) can be integrated into telescopes and provide adaptive optics corrections. However, making facesheets for ASMs is challenging. Current facesheet fabrication processes are costly and risky. Hot forming approaches for forming curved facesheets have been developed, but these methods typically require a mold for the facesheet to slump into.

Technology Description

Researchers at UC Santa Cruz have developed approaches for fabricating facesheets that also use a hot thermal forming process, or slumping. However, instead of using a mold, this approach involves placing a flat facesheet on a support structure, such as a steel ring, thus allowing the facesheet to freeform slump. A weight, such as a second steel ring, is placed on top of the facesheet, aiding the facesheet in forming the desired shape. Once the facesheet has the desired properties, the excess facesheet material between the top weight and the support structure is cut off.

This approach allows for creation of shells of a variety of radii of curvature and eliminates the need for a mold. Furthermore, this approach is an iterative one that allows for adjustments for aberrations produced by previous cycles.

Applications

• optics
• imaging

Advantages

• iterative approach allows for correction of optical errors
• eliminates need for negative form for facesheet to slump into
• allows creation of shells of a variety of radii of curvature
• adaptable for different optical prescriptions
• cost efficient

Intellectual Property Information

Additional Patents Pending

Related Materials

• Generating curved deformable facesheets via free form slumping - 08/29/2022