Canon Patent Application: IBIS adjustment - DSLR illustrations

We have seen images that show a "DSLR" incorporating IBIS, but in the past, they haven't really described the DSLR system in detail, it was simply for illustration purposes, never has it been a clear part of the patent application.  In this application, Canon still uses a DSLR as the illustration, but in reality - there's no need to do so.  The patent was filed on August 31, 2018 and just made public now.  The RF mount and mirrorless full frame were fully announced a week later.  So this patent makes me curious.  I do know that IBIS+IS probably would not work in the EF world because of the extreme communication that has to happen between lens and camera, and the fact that EF lenses were not built to include that level of IS communication to the camera body.  However, Canon could have IBIS and allow you to switch between IS and IBIS depending on the lens you have mounted.

Interestingly enough, the camera they choose to illustrate IBIS with is a 5D styled camera.  Seen in the below image.  Food for thought ;)

Similarly, when the image sensor is driven, flange-back adjustment is performed so that the image sensor is perpendicular to the optical axis and the distance from the lens mount to the image sensor is appropriate. This flange back adjustment is known to be performed when the image pickup device unit is incorporated into an image pickup apparatus, or in the image pickup device unit. In the latter case, the inclination of the image sensor with respect to the optical axis is adjusted in the image sensor unit, and the inclination of the image sensor unit with respect to the optical axis and the distance from the lens mount to the image sensor are adjusted when the image sensor unit is incorporated in the imaging device.

Now, this patent application is about flange distance adjustment in an IBIS system.  In other words, during assembly, the calibration that adjusts the flange back distance. This has to be incredibly precise.  Fast lenses such as the 85mm F1.2L IS USM require near-absolute perfect calibration of the sensor to the image plane.  Canon is concerned about the increase in the number of parts (complexity) and size when incorporating IBIS and also having to have this adjustment.

however, there is also a need size of the imaging device. When the image stabilization mechanism disclosed in Patent Documents 1 and 2 is mounted, an image sensor unit incorporated so that the image sensor is driven is attached to a member to which a lens mount is fixed. Therefore, after the image sensor is adjusted in the image sensor unit to drive a plane perpendicular to the photographing optical axis, flange back adjustment is performed when the image sensor unit is attached to a member to which the lens mount is fixed. When the blur correction mechanism disclosed in Patent Documents 1 and 2 is mounted, the number of components of the adjustment mechanism increases and the size of the adjustment mechanism increases because the two adjustment mechanisms are provided. There is a problem that the device is also increased in size.

In this patent application (which Canon uses a DSLR as the illustration) Canon comes up with a method to reduce the complexity and size of the adjustment.

 present invention has been made in view of the above-mentioned problems, and in an interchangeable lens type image pickup apparatus that performs image stabilization by driving an image pickup element, the number of parts is reduced and the size is reduced. It is an object to provide a mechanism capable of performing adjustment.

Note that in all the diagrams quite clearly a mirror is present.  This, of course, is not necessary for mirrorless cameras.  This entire patent application could also apply for mirrorless cameras as well, as reducing the size and complexity of IBIS and it's related components is clearly a must have for IBIS in smaller cameras.

Japan Patent Application 2020-034816