inverter on a camera flash

Ive been studying the intertubes for a bit now and I cant seem to find an explanation on how a disposable camera flash works in detail. I mean I understand that it runs with two transformers, one at 300v output to charge the cap and the other to help discharge the payload through the xenon bulb run at 2000v output. but a transformer doesn't work with out a pulse or rapid continuous change in voltage. so how is it inverting to ac or am I missing something stupid

I was going to direct you to my Instructable Reverse engineering for the of a Polaroid flash circuit but I only marked the two leads source red and starter white lead xenon bulb.


This is a disposable camera circuit, the glass in the xenon bulb acts like a capacitor connected to a starter coil allowing the flash.

Camera Flash 3.bmp