a friend has asked me to help them with a LED billboard type of art piece. It's envisioned to basically be ping pong balls cut in half with LEDs mounted under them. She got some jumbo (10mm) LEDs for their brightness specs, and she's happy with the brightness, but not so happy with the specularity (creates a hot spot). I explained to her, somewhat speculatively, that low specularity (wide viewing angle) and high luminous intensity are competing goals,
So on to the question. What are the parameters / characteristics to focus in on for picking an LED that will brightly and evenly illuminate the inside of a ping pong ball? Are there tried and true ways to take a really bright LED and diffuse its light onto a semi-spherical surface? Am I better off getting a wide viewing angle LED at a lower luminous intensity, or a high luminous intensity and using some kind of external diffusion strategy? Any help / advice would be greatly appreciated!