Canon Patent Applicaton: EVF Optics Improvement

Canon filed a patent application for some improved EVF optics.  The goal of the patent was to reduce the size and weight of the EVF optics, while also having a wide viewing angle.

Conventionally, in order to observe the image displayed on the image display device such as a liquid crystal panel, the observation optical system has been proposed which uses a plurality of lenses. In order to enhance visibility, these observation optical systems are required to have a sufficiently wide field of view (high magnification) and a sufficient eye relief, and to have various aberrations well corrected.

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The present invention relates to an observation optical system capable of observing image information displayed on an image display surface with high optical performance while maintaining a wide viewing angle while reducing the size and weight of the entire system. 

Improving the EVF optics is of a high priority to Canon, as the EVF viewing comfort directly relates to the adaptation of EVF's over OVF's.

In this patent, they demonstrate quite a few different EVF optic designs, some of them down to using just 3 elements.

Canon Patent Application 2020-027113