Although SPA doesn't provide polarizers, filters or gratings, our experience in using these devices aids in the specification of these devices for our clients.  A small sampling of how we've used some of these devices in particular applications follows:

• We have helped define polarizers as well as backlight diffusers to maximize contrast for companies that utilize flat panel displays.
• SPA helped define some wave-plate and polarizer combinations for stereo-viewing of projected displays.
• Gratings were defined for a spectrophotometer we helped design.
• SPA has defined filters for specific wavelength selection for use in microscopy.
• We have specified a longpass filter coating for visible light rejection for a near infra-red camera application.