I wanted to create an analog projection clock, a clock face should be projected onto a wall. I put a small clock from a cheap alarm clock at the back of a mirror surface and put the hands over the mirror. With the help of a second mirror, the reversed image is mirrored again and by shining a light on the clock mirror projects a nice clock image.
I haven't really been successful in finding a good light source. It has to be a clear single point light source or else the clock hands look too diffused. I think I found the right one in Adafruit's store: the 1 Watt cool white LED.
Now my question is: what do I need to connect it to a power supply? I don't want to use batteries, because I want my clock to run longer than a few hours. I'm not really experienced in electronics. Apart from the necessary resistors, can I attach the LED directly to the output of a power supply or will there be some other problems?
Analog projection clock
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Re: Analog projection clock
If you have a regulated supply and you run the led at less than the rated maximum current, you can get by with a simple resistor current limiter. If you want to run the led closer to maximum output, you will want to use a constant-current led driver.
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