I am not sure where I should put this, but this seems to be the best place. I want to buy, or build, an adjustable ultra-fast strobe light. By ultra-fast, I mean capable of strobe frequencies in the neighborhood of 400 THz. I want it to be minutely adjustable. I also want to be able to adjust the on/off ratio. For example, if I can set it to be on for 2 periods of time, then off for 1 period of time. Light intensity is fairly inconsequential, (it doesn't have to be terribly bright) but I would like to be able to adjust the intesity if possible. Intensity control is secondary, I could live without it, but I WOULD prefer it. It can be a stand alone unit (such as a freq generator with a voltage output that I could affix an LED to in some manner). It can be a computer controlled black box. I could even dedicate a whole computer to it if necessary. I could take one of my laptops and scavenge it if I have to. Cost is not much of a concern, though I am not Bill Gates. Any suggestions at all would be greatly appreciated.