[baobrien]

Mike Harrison of mikeselectricstuff gave a talk at the 2016 Hackaday Belgrade conference on how insanely complex these things were.

https://www.youtube.com/watch?v=3-BvMcqEc98

[beautifulfreak]

He mentions the Eidophor's only competitor, the GE Talaria, which is also interesting:

https://en.wikipedia.org/wiki/Talaria_projector