You will need resistors and heat sinks if you get the high wattage LEDs. There is a bunch of planning involved in an electronic device of this type. I recommend you study the wavelength of the sun at the spring equinox and get the right kinds of LEDs to exactly replicate from the ultra violets to the infrared.

LEDs have an anode and a cathode to mark the flow of direction of electricity. If you do the research to determine what kind of LEDs you would like to use, then post it up I will look it over and design a circuit that will work on a laptop power supply.

I recommend mouser.com or digikey.com and select only higher wattage LEDs. They are expensive, in reality your light will end up costing close to the ones on eBay. Buy in bulk and you will get a better cost break obviously.

Good luck!

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