Hi,
We've been wondering if the Lightcrafter 6500 operating in pattern mode enforces some predefined refresh rate on the mirrors? By this we mean, if I display 3 patterns with, let's say 100 ms exposure and 0 ms dark time each, does the DMD then show the first pattern for 100ms keeping the mirrors on at all times, then instantaneously switch to the next pattern and displays that for another 100ms and so on? Or when it is projecting a pattern, are the mirrors actually cycling on/off on some duty cycle during each exposure? Also, when switching to the next pattern, what is the typical delay between pattern transitions? Does the DMD turn all mirrors off during the transition.
We are asking because we're observing very poor contrast on our DMD, on the order of 2:1 between mirrors that are on and off, which is very far away from the 1000:1 or so (if I remember correctly) in the documentation. For our application we are displaying various patterns under constant illumination and mapping them using a camera, and we are trying to troubleshoot why we're getting such poor contrast - whether it is due to our optical design or some internal cycling of the mirrors.
Many thanks,
Alex
