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Something like this already exists and is cheaper than red LEDs. At least it used to be cheaper. IR LEDs. Invisible to the naked eye. If you want to see the
by VLM 6y ago
Something like this already exists and is cheaper than red LEDs. At least it used to be cheaper.
IR LEDs.
Invisible to the naked eye. If you want to see the nifty status LEDs, simply hold your cellphone camera (which is IR sensitive) and look at the phone. Bonus you can take a pix of the lights and file it with a trouble ticket or whatever.
For a good laugh start up your cellphone camera and hold it in front of a IR (not RF) remote control and push a remote button, it'll light up in a big way on camera. Some TV remotes are practically IR flashlights as in light up the room, cheap ones not as bright.
- jeffbee 6y agoSpeaking of remotes, the OP incorrectly associates the LED with the invention of the remote control, but in fact the remote control predates LEDs and solid-state electronics entirely. The first remote control (I owned one!) was acoustic. It had ultrasonic chimes and buttons. Each button hammered a chime. There were circuits in the TV that were excited by the acoustic wave, which changed the channel and all that. The Zenith "Space Command" ultrasonic remote control appeared on the market in 1956.