Homemade HD Projector with Nexus 7 Screen, Field View Camera Lens, Arduino Keystoning
Having assembled exactly one semi-complex optical-based project from scratch in my life I can verifiably say it’s something you could potentially pull your own hair out over! But patience is a virtue, exemplified in this video from YouTuber HAMMERLAND who appears to improvise solutions on the fly and modify the HD projector design accordingly. This includes some interesting ideas along the way, like the long threaded bolt for adjusting the position of the lens, and the Arduino circuit for articulating the vertical keystoning of the fresnel lens (horizontal keystoning is done manually).
As you can see the results are pretty darn good! (Display size is 100″ diagonal.)