Re: looking for nanosecond pulse LED



simba schrieb:

I am looking for a LED than can be driven buy pulse with width of
10ns~100ns order.
Such a LED is required for measurement of velocity of small particles
( size of some 10 microns order ) as light source.

This is more a question of the driver circuit than of the LED itself. If you
want to switch the LED during such short times, you have to overcome the
LED capacitance and thus your driver must be able to supply a lot of
reactive power (or you have to compensate for it with an impedance matching
network).

Also note, that in pulsed mode most LEDs can be overdriven to a multiple of
the maximum allowed CW current. And even if the LED burns you only loose a
few cents. It may pay off to use an IR-Led, since usually cameras have a
higher efficiency there.

However, LED could be a
choice if both illuminating power and speed of the LED is enough.

The speed probably is, the brightness could be sufficient if your imaging
area is very small.

Cheers,
Jürgen

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