Why is using visible light for radio transmission not feasible?

AI Thread Summary
Using visible light for radio transmission is impractical due to its short wavelength, which limits its ability to diffract around obstacles, requiring a clear line of sight for communication. While devices like TV remotes and infrared communication ports utilize visible or infrared light for data transmission, they are not effective for long-distance radio-like transmissions. The principle of long-distance transmission is feasible, as evidenced by detecting AM visible light signals from pulsars. However, the rapid attenuation of visible light signals in obstructed environments poses significant challenges. Overall, effective communication using visible light necessitates unobstructed paths between devices.
bsmith
Messages
3
Reaction score
0

Homework Statement



Why can't you make radio transmitter that transmits visible light instead in the same way we transmith AM signals?

Homework Equations





The Attempt at a Solution



Im thinking maybe they would not be very effective as their wavelenth is so small, they would die out rapidly...
 
Physics news on Phys.org
There are lots of practical devices that use AM visible or infra red light for data transmission. For example TV remote controls, infrared communications ports on PCs, etc.

There is no problem in principle with long distance transmission. For example we can detect the AM visible light signals from pulsars many light years away from earth. However short wavelengths do not diffract round large objects, so you can only communicate between devices that can "see" each other with no obstructions in between them.
 

Thread 'Struggling to understand the concept of this question (ice cube in water optics question)'

TL;DR Summary: I came across this question from a Sri Lankan A-level textbook. Question - An ice cube with a length of 10 cm is immersed in water at 0 °C. An observer observes the ice cube from the water, and it seems to be 7.75 cm long. If the refractive index of water is 4/3, find the height of the ice cube immersed in the water. I could not understand how the apparent height of the ice cube in the water depends on the height of the ice cube immersed in the water. Does anyone have an...
View full post »
Thread 'Variable mass system : water sprayed into a moving container'

Thread 'Variable mass system : water sprayed into a moving container'

Starting with the mass considerations #m(t)# is mass of water #M_{c}# mass of container and #M(t)# mass of total system $$M(t) = M_{C} + m(t)$$ $$\Rightarrow \frac{dM(t)}{dt} = \frac{dm(t)}{dt}$$ $$P_i = Mv + u \, dm$$ $$P_f = (M + dm)(v + dv)$$ $$\Delta P = M \, dv + (v - u) \, dm$$ $$F = \frac{dP}{dt} = M \frac{dv}{dt} + (v - u) \frac{dm}{dt}$$ $$F = u \frac{dm}{dt} = \rho A u^2$$ from conservation of momentum , the cannon recoils with the same force which it applies. $$\quad \frac{dm}{dt}...
View full post »

Similar threads

B Feasibility of Sending a Radio Signal Detectable from a Neighboring Star
Replies
5
Views
226
Time for radio signal to get to a receiver
Replies
2
Views
2K
Thin-film interference: transmission & reflection of colors
Replies
6
Views
4K
Diffraction Grating - all visible light?
Replies
2
Views
2K
Solving for Visible Light Reflection/Transmission: A Homework Help Guide
Replies
5
Views
2K
Finding wavelength of visible light in a well
Replies
15
Views
2K
Work function of cathode, visible light
Replies
2
Views
6K
Understanding Radio Waves & Oxygen Absorption at 60GHz
Replies
1
Views
2K
Diffraction Grating and Visible Light
Replies
8
Views
7K
B What if I could see in radio instead of light?
Replies
39
Views
6K

Hot Threads

Recent Insights

Back
Top