Can Light Replace Electricity in Modern Technology?

[seb7]

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 into 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?

 

[Mech_Engineer]

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?

Fiber optics can be used to transmit power where electrical cables have certain disadvantages (called Power Over Fiber) although it is less efficient, but I'm not aware of the possibility of "optical circuits," or anything like an optical capacitor or transistor.

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 into 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?

Now this has actually been done, although it's hard to say if it's as economical as electrical solutions. I read about a system like this a few years ago in Popular Mechanics, the system utilized a tracking parabolic reflector on the roof and plastic fiber optics to transmit light into the building for lighting. The system was paired with a fluorescent light source to use the same fiber optics for lighting at night.

I found this through a Google search: http://www.sunlight-direct.com/lighting.php

 

[Topher925]

Phosphors are essentially optical capacitors. They behave very similarly as capacitors do in electrical circuits except their efficiency is very low compared to electrical capacitors. There is also the issue of Stoke's shift. Optical diodes are essentially one way or reflective films that you might find on a beam splitter or interferometer. I believe there are some fluorescent materials that can be used as optical transistors, but right now I can't remember specifically what they are called. As far as I know there is no optical equivalent to an inductor.

I don't think light will ever replace electrons as a means for power or computing. Light has big problems with attenuation and almost everything about it is inefficient. Sending power over an optical fiber for example has very high losses. All optical fibers have some sort of attenuation which decreases the light signal and heats up the fiber. Most high power fibers are extremely expensive due to being very pure silica and are typically never rated past a few watts. If a large amount of power is being transmitted through the fiber and there is a large impurity (couple nanometers), the fiber will literally melt and burn up.