How to design a reflector?

Hello all. I'd like to make a larger head for my t500 MicroFire. But how do you go about designing the reflector? We've all seen the line drawings of a side view reflector with the lines emenating from the bulb and bouncing off the curve of the reflector. How do you know which way the light will bounce?

When the curve of the reflector is parabolic and the light source is placed at the parabola's focus, the light will collimate into a beam. Now, which section of the parabolic curve you use is up to you. If you use a small section (shallow reflector), you'll get a wide spill and not a lot of hotspot. If you use more of the curve (a deeper reflector), you'll get a brighter hotspot and narrower spill.

This would be a shallow reflector The equation is y=1/4x^2



This would be a deep reflector. The equation is y=x^2


IIRC, the equation for the focus is 1/4a. A is the coefficient of x. So, the focus for the shallow reflector is (0,1), and the focus is (0,.25) for the deeper one.

Is there software to design any type of reflector? So you can virtually design your reflector & see what beam it will produce. Then once you have what you want, give the plans to somone who makes reflectors. It would really nice to have alot of choices. Like for what kind of light, incan, short arc, you could design exactly what kind of spot or flood, beam width. Seems theres only a few generic reflector types around.

thx

You should check: http://www.lambdares.com/products/tracepro/index.phtml

Last year I used it to design some reflectors, you can contact them, they sell a full preview version with manuals valid for 30 days for $100

check this thread: http://candlepowerforums.com/vb/showthread.php?t=125342


Pablo