how do I know how to power an LED?

Hi,

I just got a RL5-UV2030 405 nm ultra-violet led 20mw, and I want to know what the best type of battery to use to power it is. I am going to be putting it inside the base of a narrow plastic tube to light it up, so the smaller the battery the better.

I also need to know what sort of resistor I will need..

-patrick

I assume you will operate it at 20mA. The length of time you want it to run off the battery will determine the battery size and type.

Light Emitting Diodes (LEDs) that should get you going

actualy if you look at the links at the bottom of the page i gave if your new to electronics its a good basic site that explains well