Layered infrared transmitting optical elements and method for making same
US9981459B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 14, 2014 |
| Grant date | May 29, 2018 |
| Priority date | — |
| Expiry date | Jan 28, 2037 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB32B2551/00
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
A method for bonding infrared transmitting glasses into an optical element without interlayer voids by stacking at least two different infrared transmitting glasses inside a vessel where each glass has a different refractive index, a different dispersion, or both, and where the glasses all have similar viscosities, thermal expansion coefficients, and glass transition temperatures; placing a weight on top of the stack; applying a vacuum to the vessel; applying an isostatic pressure of at least 1500 psi; and after releasing the isostatic pressure, annealing at a temperature within 10° C. of the glass transition temperature at a pressure between 0 and 1000 psi. Applying the vacuum, applying the isostatic pressure, and annealing are done sequentially and with no intermediate transitions to ambient temperature or pressure. Also disclosed is the related optical element made by this method.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.