Years ago, it was talked about how light could be used instead of electricity. How far have we come with this idea? Do we have today any kind of transistor/diode/capacitor version that uses light instead? I was also wondering if there’s such a device that looks like a solar panel, but is actually a bunch of tiny light reflectors which narrows the light received on the surface to be tunnelled in to one small fibre. Example of use could be light up the inside of large complex buildings with needing large windows. Is this possible? has it already been done?