Optical Filter for Undersea Blue-Green Laser Communication

We propose to build and test two types of polarization interference filter stages to achieve the goal of a ninety-degree full cone angle, field of view. These filter stages will be of different designs that both have the potential to meet this goal. They will have a 45 millimeter diameter clear aperture and a transmission peak full width at half maximum of less that one nanometer at a wavelength of 532 nanometers. The designs and materials chosen for these filters can be scaled up to clear apertures of at least eighty millimeters diameter. The proposed filter stages will be the basic building block for a complete filter system to be built and tested in Phase II.BENEFITS: The technology developed here will form the basis for a laser communication detector system that can benefit free space laser communication systems during fog and precipitation as well as enabling submarine laser communications. The retarder components developed will enhance Meadowlark Optics' line of commercial retarder products, as well as improving the performance of our line of filter products.