So, has anyone designed a glass with UV lights in the bottom???Tonic water will fluoresce under UV.
Don't know... but my young padawan made a bottle with UV LED under the stopper.So, has anyone designed a glass with UV lights in the bottom???
TV remotes and such us IR LED's, not UV.Most digital cameras will display UV LEDs in their displays when pointed at the LED. Mine did when I pointed the TV remote to it and pushed buttons of the remote.
Well at least I thougt I read IR Just too many darn names for all those various parts of electromagnetic spectrum.just a point of clarification. Leftyretro said;
TV remotes and such us IR LED's, not UV.
In the old days, LEDs were cast in a plastic that was colored to block the off-spectrum light. Red LEDs were red, green LEDs were green, etc.I got it in an LED grab bag. It's clear (no color) out-of-circuit, but glows red when in-circuit. Is this a special kind of LED?
As a child of the 60's, I remember we used to turn off the white lights, and turn on the UV. Lint on dark pants would brightly glow, providing a bit of amusement.
--Rich
I love this! Thanks Wookie!With "grab bag" LEDs, you'll never know what you're actually getting. Most of them will be safe to operate at 20mA. You can create a 20mA constant current source by using a 62 Ohm resistor and an LM317 voltage regulator to help you sort out your LEDs, and determine their Vf's (forward voltages) in conjunction with a digital multimeter (cheap nowadays).
Connect the 62 Ohm resistor from the OUT terminal of the LM317 to the ADJ terminal. Connect a 7v to 12v source to the IN terminal. Connect your LED from the ADJ terminal to the return path (ground). Measure the Vf across the LED.