In this patent application (2023-125584), Canon is attempting to design lightweight telephotos with good optical characteristics.
First up we have some full-frame telephotos ranging from a 4x 200-800 F5.6-9 to a 6x 100-600mm F5.6-9. The designs are interesting, but they, even with F9.0 would have some pretty big front elements, and at least two large groups, balancing these lenses may be difficult, and if they are lighter, that may actually work against the lens. The IS units seem to be quite a bit more forward than usual on the two telephoto designs. The telephotos are also at the minimum 1.4x tele-extender friendly, with the 100-600 most likely capable of supporting the 2x tele-extender as well.
The APS-C lens would not be used on the RF mount or even the EOS-M mount. It could though be used on an APS-C powershot. With a back focus distance of 10mm, it's not suitable for any Canon ILC (interchangeable lens camera).
Canon RF 100-600mm F5.6-9
focal length 100.02 231.27 599.98 F number 5.83 7.10 9.20 Half angle of view (°) 12.21 5.34 2.07 Image height 21.64 21.64 21.64 Total lens length 300.08 336.79 373.49 BF 77.78 77.78 77.78
Canon RF 200-800mm F5.6-9.0
Focal length 206.00 404.42 775.96 F number 5.83 7.10 9.20 Half angle of view (°) 6.00 3.06 1.60 Image height 21.64 21.64 21.64 Lens total length 330.07 361.31 392.54 BF 38.46 38.46 38.46
Canon APS-C 20-150mm F4-F8
Focal Length 19.99 51.56 150.00 F Number 4.12 6.60 8.12 Half Angle of View (°) 30.77 14.84 5.20 Image Height 11.90 13.66 13.66 Lens length 118.37 134.53 150.69 BF 10.01 10.01 10.01
As with any Canon Patent Application. This may not be used to create an actual product, and may not even get processed into a published patent by Canon. It does however give us a glimpse into what Canon is researching.