The shake reduction system Pentax has installed on its new generation digi-SLRs looks like it could be reverse engineered to provide the most professional method to oscillate a ground glass. It uses magnets and ball bearings in an elegant solution ; see here

http://www.dpreview.com/articles/PentaxK10D/Images/Features/sr.jpg

http://www.dpreview.com/articles/PentaxK10D/Images/Features/srdiagram.jpg


What may be mouth watering is the availability of this as a part for purchase as an assembled sub unit.

Oh jeah, Canon`s new 400D will have much-much more compact piezoelectric vibration system but I quess it`s not planar or biaxial. See it here (http://www.youtube.com/watch?v=_P8_LNmpFSc) at 1:20
Quite compact I think but fills only academy frame.

Regs,
T

I think, determinative is here(by building 35mm adapter) how much system can give vibration amplitude. To get electromagnet vibrate with more than 2mm(approximate essential minimum) not difficult maybe to achieve high enough frequncies is difficult but piezo needs about 1000V to get distorted 1mm. So definately You need there good compact voltage multiplier.

Judging from the diagram, its the whole centre plate which vibrates so it would be simple to file out a bigger hole for full frame 35mm gg; such as a frosted microscope glass slide or your gg of choice. Also by drilling extra holes to reduce mass would allow larger amplitude and frequency of vibration for a given current through the coils. I suspect those coils are rated for audio level line signals so that the oscillatory signals could be fed by a cheap stereo mp3 player.

It is the robustness of the design which appeals to me; with the only point of wear being the ball bearings which are simple to replace (being held at the correct pressure by screws in those brass housings) and since this unit is in the K110D I am guessing the sub unit would be available as a replacment part for around the 150 dollar mark, without the CCD of course.