What Strobe Frequency to set?

[mpf]

Hi all,
I am designing a high current controller with a strobe function (amoung many others)
My question is what should the strobe frequency be.
Fitting frequencies seem to be 5Hz to 30Hz.
At the moment I have set it just below 4Hz.

Any suggestions?
matthew

 

[matrixshaman]

I guess that would depend on the intent of the strobe. I believe the strobe in the Gladius flashlight was researched to be the most disorienting strobe frequency. I don't know exactly what that is but maybe someone around here does or could check it with an oscilloscope and photocell or some setup like that.

 

[dulridge]

Hi all,
I am designing a high current controller with a strobe function (amoung many others)
My question is what should the strobe frequency be.
Fitting frequencies seem to be 5Hz to 30Hz.
At the moment I have set it just below 4Hz.

Any suggestions?
matthew

Vague memories from many years ago - 9Hz strobing is supposed to induce epileptic seizures in many people, even those not known to be susceptible. This wikipedia article may be of some use. http://en.wikipedia.org/wiki/Strobe

 

[VidPro]

if it is used for the purpose of a Beacon for emergency rescue, the "on-Time" would be more important than the strobe frequency.
if your in a situation where you NEED a strobe, the runtime of the unit is going to be important.
because leds have a very fast on/off time, a 10htz strobe with a short on-time should last days.

when playing with flashlights with strobe the extreemly slow strobe was rather uneventfull, boooring. but it might still be great for a rescue, but as a emergency flare on the road, i would want it to be more obnoxious, and stand out as something more than a fluke.

 

[mpf]

Thanks for all the comments.
Since the strobe mode is being designed for visability rather then offensive use I will keep the frequency below 5hz (I wouldn't want the driver of a passing car the have a fit and crash)
As suggested by VidPro, I am shorting the ontime of the flash to extend the battery life. The strobe current is already adjustable so the user can set the brightness (and hence runtime) to what ever they think is appropiate.
Since the regulator is a linear buck type, as the battery dies the flash just gets dimmer but keeps going for hrs and hrs (on alkalines).
matthew