Purple Haze was acid (LSD) first, before it was any thing else. It coexisted with other long obsolete LSD like Orange Sunshine and such. The purple haze in his eyes is, I think, the hallucinations. He wa smost probably tripping while dreaming (hope that fits in with everyones story okay).

We used to get LSD in lquid form and drop it in our eyes using a visine dropper. I don't know if the original purple haze was microdot or liquid, but that could be the other way he got it in his eye. Probably not an accident.