I was talking with some of my friends on the VGPC Discord channel, and we were talking about getting PSX ringcodes with a scanner.
We had talked about how LEDs didn't work, but incandescent lights did work. oezr had just posted an image showing the spectrum of LEDs, which showed that incandescent bulbs produced a lot of infrared light.
My thought was that the infrared light is what causes the ringcode to be visible.
With that in mind, I grabbed my nearest source of infrared light: the "Night Vision googles" that had at one point came from the Prestige Edition of CoD MW2, but I had picked up at a Goodwill. More info here http://n4g.com/user/blogpost/sangria/430144
These are the results:
I would appeciate it if anyone could pick up a cheap IR flashlight on Amazon or something to confirm that IR lights work for all scanners.