Canon Patent: Quarter Wave Element Lenses
In this patent application (2025-040503), Canon further explores this reflective and transmission phased layer to produce some wild lens designs. I will have to come up with a name for this element, as I have a feeling we will see a lot of it. Now, it's still possible that Canon may never do these lenses with this layer, as we have no idea how difficult it is to mass produce.
Look at the other patent application on some really esoteric ultra-wide lenses using this technique.
All of these lenses, though, would never be in an RF mount configuration. It would be impossible. The lens almost touches the sensor, having a back focus distance of only .1mm. These lenses may make it into a dedicated camera system, but with a .1mm back focus distance, I struggle to even think of a camera system these could be used with, as any vibration or thermal expansion and the element would be touching the sensor.
Looking at the below example, which is a 50mm F1.5 lens for a full-frame sensor but with a back focus distance of .1mm, you can see the HM1, HM2, and QWP elements reflect incoming light and bend it so that the image circle is large enough for a full-frame sensor. That is an amazing feat when the elements are close to the sensor.
This is a Patent Application
As with all patent applications, this is a look into Canon's Research and may not end up in an actual product.
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Richard @ CanonNews
Richard has been using Canon cameras since the 1990s, with his first being the now legendary EOS-3. Since then, Richard has continued to use Canon cameras and now focuses mostly on infrared photography. Richard is the founder and editor of CanonNews since 2017, and has worked as a writer on CanonRumors and other websites in the past.
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