US Patent 11975962 Hermetically sealed transparent cavity and package for same

A hermetically sealed package includes: at least one cover substrate and a substrate arranged so as to adjoin the at least one cover substrate, which together define at least part of the package, the at least one cover substrate being in a thermally prestressed state and bonded to the substrate adjoining the at least one cover substrate in a hermetically sealing manner by at least one laser bonding line, the at least one cover substrate being made of a material which has a different characteristic value of a coefficient of thermal expansion than the adjoining substrate and a thermal prestress is established in the package; and at least one functional area enclosed in the package.