How big is the path of an IR emitter

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The discussion centers on the signal path of an infrared (IR) emitter used in remote controls. When a button is pressed, the IR signal typically emits from the LED in a cone shape, with a divergence angle of a few degrees, often extending to several tens of degrees. Observations through a mobile phone camera confirm the flashing of the IR LED. Additionally, IR signals can be reflected by walls and furniture, which can help trigger the receiver even when not in direct line of sight. Understanding this can enhance the effectiveness of using remotes from various positions.
MartinJH
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This is a very silly question but anyway.

When using a remote for a TV or digital channel receiver, how big is the path/signal emitted from the remote when a button is pushed.
Will it come from a point, thee emitter, and form a cone shape until its picked up by the receiver.

its a dull question, I know. :)
 
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From what I found, most IR LEDs emit into a divergence angle of a few degrees.
 
If you look at it through your mobile phone camera, you'll see it flashing. (...Looking...) Hmm, I'd say it's more like few 10's of degrees. Also IR is reflected well by the walls and furniture, often this reflected light is sufficient to trigger the receiver.
 
Andy Resnick said:
From what I found, most IR LEDs emit into a divergence angle of a few degrees.

Thank you.

Delta Kilo said:
If you look at it through your mobile phone camera, you'll see it flashing. (...Looking...) Hmm, I'd say it's more like few 10's of degrees. Also IR is reflected well by the walls and furniture, often this reflected light is sufficient to trigger the receiver.

I always use that method when in bed or not in direct path to the TV :) lol.
 
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