Invention:
This invention removes the diattenuation and retardance of a metal coated mirror using an additional uniaxial birefringent coating and anti-reflection coating. The method can additionally improve the angular response of any metal coated mirror by reducing the variation of the polarization aberration with angle. The invention includes coating designs, manufacturing methods, and a discussion of its applications.
This technology is the first step in opening up a new path into reflective optics. The polarization of light can hold a lot of information in applications such as astronomy. This coating could also be used in display technologies.
Background:
Metal coated mirrors are used throughout optics for reflecting, redirecting, and separating light. These mirrors are already available due to their low costs and reduced chromatic dispersion. However, a mirror can act as a weak polarizer, and an optical retarder can introduce unwanted polarization aberration by changing the polarization state of incident light. This is one example of many different types of possible aberration in an optical system. Removing this aberration or minimizing it would open a new set of possibilities for reflective optics.
Applications:
- Thin film coating
- Polarimetry
- Interferometry
- Metrology
- Communications
- Display and imaging technology
Advantages:
- Reduction of the difference in maximum and minimum optical transmittance
- Reduction of the difference in optical phase shifts
- Reduction of polarization aberration variation with angle
