Current Olympus cameras use magnetic levitation of the sensor for IBIS, and they may well own the patent.
Magnetic levitation? If so, you would never want your camera close to a magnetic field...
But you may be right, found this from an Olympus website:
“Turning on the OM-D camera energizes a coil and magnet arrangement that causes the image sensor to float in magnetic suspension. This allows the image sensor to move freely, so it can be rotated or moved vertically or horizontally depending on the movement of the camera. It can also be used to compensate for the gentle vibration that occurs when the user is walking, such as when recording video.”
It may be the way to go for multi-axis systems, else each axis would need some sort of bearings and guides.
As I said elsewhere, 'suspension' and 'levitation' are different things.
I found this You-Tube video of the Olympus IBIS working
It shows clearly that it isn't magnetically 'levitated'. It's held down with springs, sliding against a backplate which keeps it correctly located in the image plane.
Thanks for the link. I can only make out 3 axes shown moving, not 5.
I see that's been explained so no need to add. Just to say, the sensor has to be kept in the focal plane, otherwise the image will be out of focus.
The springs are not conclusive at excluding levitation. They may be needed when powered off. I wonder if there is additionally a mechanical lock for the axes when powered off - else it would be quite fragile to shocks in transit....
Right now, we're in Russell teapot territory. So far, no-one has produced a source that says it is 'levitated'. There is a source that says it is 'suspended' (though even then, not a strong source, a popular description by a journalist, and journalists often get the technical details wrong). So, the assertion that it is 'levitated' depends on insisting that 'suspended' means 'levitated'. Really, the onus is on those who insist on 'levitation' to prove that, not those who think that Olympus will have used the obvious, satisfactory and well tried engineering solution. For a start, none of the technical information that is available (until and unless one of the proponents of 'levitation' finds otherwise) shows any 'levitation' mechanism in any Olympus document, the default assumption would be that Olympus has used the sensible engineering solution.
On that solution, it is essential that the sensor be accurately aligned in the image plane If you look at Roger Cicala's recent teardowns, you'll see that cameras include precise adjustment (either shims or spring and screw) to ensure that alignment. In the case of a 'magnetically levitated' sensor, that alignment has to be maintained by active control, with a feedback loop and a mechanism for constantly the position and parallelism (in 2 dimensions) of the sensor. Not impossible, but it is some extra, and not so simple engineering. So then we think, what would be the advantage of such a levitation mechanism over a simple low-friction mechanical arrangement.. The sole one that I can see is that it reduces friction a bit, which in turn will reduce the power needed to move the sensor. Against that it's more complex, expensive and prone to failure than the mechanical mechanism. It's not even clear to me that there would be any power advantage, since it would take power in any case to maintain the levitation, which would likely offset any power saving from the friction loss, and then since the sensor unit has to be mechanically connected in any case (through the hold-down springs and the flex PCB) there will be mechanical resistance to movement in any case, and the sliding friction of the sensor unit is likely insignificant. Then the extra weight of the levitation mechanism will add to the inertia, which is another negative. In the end, the mechanical slider is the better solution, and I suspect that, the good engineers that they are, Olympus will have used the better solution.
But as I said, so far no-one has shown a source that says that magnetic levitation is used. Those that propose the unusual are the ones that need to back up their claims with evidence.
