Skip to main content
Image
Fabrication of height modulated and tapered features in fused silica

This LLNL invention allows for the fabrication of complex waveplate features and topologies from fused silica, a highly desirable and durable waveplate material.  It also is a unique technique for density multiplication and high-fidelity bidirectional deposition, which can create optical components that are generally for entirely new classes of optical materials.

Left Image Caption…

Image
Schematic showing how laser can be used to induce localized heating

LLNL researchers developed a novel strategy that involves material transformations such as oxidation, nitridation, or carbonization. In one embodiment, copper is heated under ambient conditions resulting in its surface being oxidized and turned into copper oxide, where a new material (e.g., copper oxide) is developed via transformation (e.g., oxidation) without additional addition deposition…

Image
Standing in LLNL’s Center for Micro Nano Technology, Nathan Ray holds a marvel of optical engineering, a 5-centimeter metasurface optic

This LLNL invention concerns a method for patterning the index of refraction by fabricating a spatially invariant metasurface, and then apply spatially varied mechanical loading to compress the metasurface features vertically and spread them radially. In doing so, the index of refraction can be re-written on the metasurface, thus enabling index patterning. This process allows rapid 'rewriting…

Image
SEM image of etched metasurface with angled features

This novel invention specifically enables the fabrication of arbitrarily tailored birefringence characteristics in nano-structured meta-surfaces on non-birefringent substrates (e.g. fused silica). The birefringent nano-structured meta-surface is produced by angled directional reactive ion beam etching through a nano-particle mask. This method enables the simultaneous tailoring of refractive…

Image
Schematic of one methodology for achieving a thicker substrate engraved meta-surface (SEMS) layer

This invention (US Patent No. 11,294,103) is an extension of another LLNL invention, US Patent No. 10,612,145, which utilizes a thin sacrificial metal mask layer deposited on a dielectric substrate (e.g. fused silica) and subsequently nanostructured through a laser generated selective thermal de-wetting process.

Image
large potassium dihydrogen phosphate KDP crystal

This invention takes advantage of the high water-solubility of key NIF KDP crystal optics and uses water as an etchant to remove surface defects and improve the laser induced damage threshold. Since pure water etches KDP too fast, this invention is to disperse water as nanosized droplets in a water-in-oil micro-emulsion. While in a stable micro-emulsion form, the surfactant additives prevent…

Image
LLNL’s CO2 laser-based Optics Mitigation Facility adapted for controlled laser melting of glass optics.

This invention proposes to use laser induced melting/softening to locally reshape the form of a glass optic. The local glass densification that results induces predictable stresses that through plate deformation mechanics yield a deterministic methodology for arbitrarily reshaping an optic surface figure and wavefront without the need to remove material.

Image
Scanning electron micrograph of scalable, grating-like nanoscale metal mask (line period ~35 nm)

This invention consists of a method of forming nanoscale metal lines to produce a grating-like mask with wide area coverage over the surface of a durable optical material such as fused silica. Subsequent etching processes transfer the metal mask to the underlying substrate forming a birefringent metasurface. This method enables the production of ultrathin waveplates for high power laser…

Image
Scanning electron micrograph of bulk metamaterial structures fabricated at LLNL

Heat sensitive materials such as piezoelectric and MEMS devices and assemblies, magnetic sensors, nonlinear optical crystals, laser glass or solid-state laser materials, etc. cannot be exposed to excess temperatures which in the context of this invention, means materials that cannot be exposed to temperatures greater than 50°C (122°F). LLNL’s invention describes a low-temperature method of…

Image
Linearly polarized light entering a half-wave plate can be resolved into two waves, parallel and perpendicular to the optic axis of the waveplate ("Waveplate" by Bob Mellish is licensed under CC BY-SA 3.0).

This novel method of producing waveplates from isotropic optical materials (e.g. fused silica) consists of forming a void-dash metasurface using the following process steps:

Image
Hand polishing optics

LLNL's Slurry Stabilization Method provides a chemical means of stabilizing a polishing compound in suspension at working concentrations without reducing the rate of material removal. The treated product remains stable for many months in storage.