Originally posted by rawr
So I expect any Sigma reverse engineering will proceed very cautiously in future.
That had nothing to do with reverse engineering.
Actually, in the same trial the year before, the same judge ruled that Nikon's VR patents (from 2002) are "void and null" because made up from older patents from other inventors. Also, the "damage" was reduced considerably.
I guess Nikon will think twice before sueing Sigma again. All of that having nothing to do with the mount (which the reverse engineering comment applied to).
Actually, optical image stabilization is patented since 1976 (Canon, idea: tilt a prism). Later, Konica Minolta patented to shift the sensor and Nikon to shift a lens (anybody knows who patented to tilt a lens?). But it is all the same core idea, measure yaw and pitch (gyros) and shift the projected image to compensate (with differences being to tilt or shift, lens or sensor, piezo or voice coil, hall effect control loop or not, rotate or not etc.). So, they are all violating each others patents. There is no escape when doing SR, it all is a question of patent portfolio power. Seems, like Sigma could settle that issue now as well.
Interesting, nobody patented a "mass inertia" optical stabilization: a lens element coupled to an movable mass in such a way that any pitch or yaw would automagically move the mass-coupled lens element to counteract the movement. I.e., passive as opposed to active OS. When I first heard about OS without knowing more details, I was immediately thinking passive OS abd that the entire idea would be a lot older than 70's. Actually, now thinking about it, Canon's tilting prism, coupled with a little gear box, two little solid cylinders, spring and dampening, could be turned into a passive OS quite easily.