Canon EF 70-300mm f/4.5-5.6 DO lens patent shows up in Japan

Canon has patented two new zoom lenses in Japan, one with a 100-400mm focal length range and the other one with a 70-300mm range, but both with a diffractive optical element.

The “year of the lenses” has begun at Canon with the launch of the EF 16-35mm f/4L IS USM and EF-S 10-18mm f/4.5.5-6 IS STM models in mid-May.

The rumor mill is claiming that more lenses will be revealed by the end of 2014, including a wide-angle zoom with an f/2.8 aperture and a replacement for the EF 100-400mm f/4.5-5.6L IS.

In the meantime, the company has patented two new models in Japan and one of them could be the successor of the 100-400mm version.

The two newly-patented lenses are the Canon EF 100-400mm f/4.5-5.6 DO and the Canon EF 70-300mm f/4.5-5.6 DO.

Canon EF 70-300mm f/4.5-5.6 DO and EF 100-400mm f/4.5-5.6 DO lenses patented in Japan

The patent for the Canon EF 70-300mm f/4.5-5.6 DO lens. A version of this lens is still available on the market, but it appears that the company has finally decided to replace this model.

Canon has been rumored to release a new 100-400mm optic for a very long time. Several patents have been spotted among these rumors, but there is room for another one.

This version consists of 17 elements split in 11 groups with a fluorite component as well as a diffractive optical element.

The Canon EF 70-300mm f/4.5-5.6 DO lens features a similar configuration with 17 elements in 11 groups as well as fluorite and diffractive optical elements.

What’s a diffractive optical element?

Canon has been employing diffractive optics in some of its lenses for several years. The DO technology allows the company to make high-quality lenses while preserving weight and size.

The multilayer diffractive elements are made by adding diffractive coatings to lens elements. This way, lenses become smaller and lighter, while also increasing image quality.

The increase in quality comes from the fact that the DO elements do not disperse light, such as conventional models. When light disperses in a lens, it creates chromatic aberration. However, when using diffractive optics in a lens, chromatic aberration is cancelled out, says Canon.

An example of a Canon DO lens

As stated above, Canon has released DO lenses on the market. One of them is the Canon EF 70-300mm f/4.5-5.6 DO IS USM lens which has been around for about ten years.

The new patent is suggesting that a replacement for this optic is finally on its way. The current generation is still available at Amazon for about $1,400, which remains a good deal considering the fact that the launch price of this model has been set at $2,300.

Once again, there is no release date, but an announcement could take place sometime this summer, so take this with a pinch of salt for now.