What to expect without the optical fiber ?

[Externet]

Setting a pair of these one in front of the other with sight of their optical ports aligned, no optical fiber ?
Would it be an over-the-air optical LAN link ?

----> **broken link removed**

Now, what to expect if the optical ports were fitted some lens instead of the fiber connector, like to diverge/sense a wider angle ?
Would some wider dispersion be achieved ?

Same for USB-to-light converters... ----> http://www.ratioplast.info/index.php/en/productlinie/product/view/163/900
For doing an over-the-air link within a room.

 

[FvM]

Without concentrating (not diverging) optic, I wont expect more than 5 or 10 cm range due to optical power decreasing with squared distance. Refer to IrDA for larger range https://en.wikipedia.org/wiki/Infrared_Data_Association

 

[Externet]

Thank you, FvM. Good informative link.
Thought that the emitters being more powerful than a plain TV remote, range could be larger than for a TV control. But multipath reflections becoming problematic at high data rates.

 

[FvM]

IT remote control uses high transmitter current and very sensitive, low bandwidth receiver.

 

[BradtheRad]

I used a narrow-beam led (bright orange) to flash at a photosensing circuit across the room. I amplified the photodiode signal but to get reliable operation I had to mount a magnifying glass in front of the photodiode.The magnifier was 1 inch diameter with focal length a couple inches.

Transmission rate was very low, only 10 flashes per second maximum.