Originally posted by ExDelayed:Halos are easy, some clear acrylic rods, heated and bent around a tube the size you want. Notched either on the inside (facing the lamp) or on the front (facing out) and lit with two LEDs. Not hard to build knock-offs. OEM BMW pieces go for a bit more.
ANGEL EYES They came on the 2001 BMW and has been a popular design to copy. Here is a few examples of how to make them:
* 3/8 inch acrylic rods can be heat bended in a circle. In each end insert a high brightness white LED. For double the light, make 2 half circles and insert 4 LEDs instead of 2. To get the light to hit the rod, it need something to light up: Create small vertical cuts on the back with 2-3mm spacing. A dremel with a circular cutting blade is excellent to do this job. To create the best optical contact between the LED and the rod, use a 100% transparent glue or silicone.
* White 12" spaced white LED flexible arrays from Radiantz.com can be mounted around a projector headlight to make a similar appearance. Picture shows a Audi A6 projector unit embrased by the LED array inserted into a Nissan Maxima headlight. Thanks to multi talented "MGB" for these pictures.
* Home made LED array. In general, any kind of LED will do. There is a few things to consider. Colorwise, I would choose white and not the blueish white to keep the cops happy. I'd say the more LEDs you solder in there, the better will it look like a continous circle. Look for LEDs that have as high opening angle - at least 30 degrees. LEDS tend to be bright straigth ahead and very dim to the side. Also note the maximum current you can send through a LEDs at certain tempratures. A typical hi-power LED can take a max 30mA of load at room temp. On a hot summer day, inside temp of a headlight can go up to maybe 50-100 degree Celsius, all depending. At that temp, max load is maybe 10mA. So look for LEDs that can run as high current as possible at elevated temperatures. If its labled for automotive purposes, its usually a high temperature span on it.
