Audio signals transferred by a light source

[cynricng]

Hi, I am currently working on a little science project, I came across this page about sending audio signals through a laser pointer.

http://www.i-hacked.com/content/view/162/44/

I was wondering if it is possible if I did it with an ordinary light bulb.

It said that the data is transferred by the light's amplitude, so if I were to use a light bulb instead of a laser point, does it kind of mess up the signal if I were to stand closer or farther from the receiver? Or does the audio output on the receiver will just have a lower volume if I stand farther away?

Thanks.

 

[Dr_Morbius]

The problem with an incandescent light bulb is that it's response time is slow and may not accurately transmit higher frequency sound waves, But it's not impossible. I remember seeing a project for what you are describing using light bulbs when I was a kid. You could also do it with LEDs.

 

[cynricng]

LEDs would seem to be the closest thing I have in mind.

But will the distance of the light and the receiver change the volume?

 

[That Neuron]

No, The distance shouldn't affect the volume (provided the device you are using is dependent upon luminosity for volume) if you have a true laser... because the luminosity would be relatively constant... no diffusion, but if you are using an incandescent bulb or LED then yes distance will affect the volume.

 

[cynricng]

Oooh, i get it.

That's exactly the effect that I was hoping for.

Thanks.