Realistic digital holography demonstrator: a STEM outreach tool for teaching optics and lasers

The US Air Force (USAF) is interested in using lasers and optics for sensing and directed energy applications. These systems must overcome atmospheric turbulence, which distorts images and complicates detection. Digital Holography (DH) is a sensing technique that enables measurement of atmospheric turbulence and allows for improved capabilities for imaging and sensing applications. Researchers must explain their work to audiences without laser and optics expertise, ranging from high-level decision makers to high school and undergraduate students as part of STEM outreach events. STEM outreach is also a critical component to ensuring future leaders with technical understanding and awareness. There is a need for a simple demonstration tool that can cater to a range of audiences while also accurately mimicking a real-world DH system. In previous work, USAF researchers built DH demonstration systems that explain the science and engineering involved with imaging through atmospheric turbulence and showing that aberrations can be corrected with digital methods. Our DH demonstration tool adds to previous work by introducing a reflective imaging geometry which leads to speckle from rough surface scattering and a true pupil plane in which we may introduce isoplanatic turbulence. Additionally, the system is less expensive than previous demonstrators, allowing for widespread use in optics education programs.