Nakayamaon and Yasuo on August 23, 1983. This is the basic patent that uses a thryistor to quench the flash mid stream so to speak.
Several enhancements have been made since then but the original patent has expired in 2000.
Cheers,
James
At 12:51 PM 1/8/2009 +1000, you wrote:
rebphoto
> I had much more consistancy using one
> of my Vivitar 283's and my Nikon FE.
<whispers> you know Vivitar own the patent to the thyristor circuits used in *all* auto-flash units and license it to other vendors ;)
k
