Something called Fluidics was in vogue in the
sixties. It used compressed air and shaped
channels in plastic blocks that formed OR gates,
AND gates and flip-flops. It allowed control
systems where electricity was not desired. And
a few years ago a colour television projector
was demonstrated using the light from three
laser diodes mechanically scanned onto a screen.
Or a wall. Could have been mass produced very
easily I would have thought. Now we have the
flat screen LCD sets appearing in our shops.
They were developed for laptops and having
invested in producing them, the mass television
market is being invaded. But they are not
simple, it really is brute force having millions
of drivers for each pixel. But it can be done.
Still cannot quite believe it! But that simple
laser scanner is definitely not wanted now