Canon Is Developing a Lens Coating Without PFAS-Laden Fluorine

Canon is working on a fluorine-free optical coating that offers the same water-repelling qualities and durability of fluorine, but without the PFAS problems.

Per- and polyfluoroalkyl substances, also known as PFAS, have been used in a wide range of consumer products for over 70 years. PFAS are common in nonstick cookware, water-resistant clothes, and even photographic lenses. Unfortunately, PFAS are essentially “forever chemicals,” and they get into people’s bloodstream through the air, soil, water, and food. PFAS are linked to several serious human health conditions, and legislation to regulate or ban PFAS chemicals is popping up around the world.

As Digital Camera Life reports, Canon Optron, an optical materials company within the Canon Group, is actively developing a new material that offers the same water repellent and durability qualities as fluorine coating, but without the fluorine.

As Digital Camera Life rightly observes, it is very easy for photographers to take fluorine coating on lenses for granted. It’s an extremely common thing mentioned by lens manufacturers, who frequently tout a fluorine-coated front element as being more resistant to water droplets and easier to clean.

Canon’s first lens with fluorine, the EF 70-300mm f/4-5.6L IS USM, arrived in 2010. Nikon’s first lens with fluorine, the AF-S 800mm f/5.6E FL ED VR, arrived just a few years later.

Unfortunately, fluorine coatings are related to PFAS. As the full name suggests, “per- and polyfluroalkyl substances,” PFAS are a group of synthetic organofluorine chemical compounds. PFAS have multiple fluorine atoms attached to an alkyl chain. Various regulatory bodies approach fluorine in different ways as it relates to PFAS, but the European Union, which is at the forefront of PFAS regulation, specifically targets fluorine coatings, as they are, essentially, a type of PFAS compound.

While relevant regulations are not yet in full force, they feel inevitable given the EU’s stance that PFAS usage and resulting pollution pose a “significant and long-term threat to human health and ecosystems.” That does not sound like a situation the EU is likely to leave unregulated.

Canon and the rest of the photographic lens industry must grapple with the risk that lenses with fluorine coatings could become illegal to export to and sell within Europe, a major market. If Europe bans these types of products, other regions will likely follow, and no lens company is keen to have fractured lens manufacturing processes for different markets.

This means Canon needs a fluorine-free optical coating that delivers similar performance and benefits to fluorine coatings. High-end optical performance and durability are paramount.

As the videos below from Sony, Nikon, and Tamron show, fluorine coating is currently an essential component of photographic lenses. The benefits are obvious, but the world is catching up to the potential downsides.

Canon Optron’s solution, with the not-so-catchy name “Dev-02-003,” can withstand abrasion and wear to a very high degree, which is extremely important when dealing with a front element of a lens that will be regularly cleaned through friction. Durability has been a significant challenge for previous fluorine-free chemicals, like Canon Optron’s OR-510.

Unlike OR-510, which is not very durable at all, Dev-02-003 was able to withstand 10,000 instances of a scratch-resistance test. The material withstood both fabric abrasion tests and wiping tests with an alcohol-dampened cloth.

“‘Dev-02-003’ is fluorine-free yet can withstand harsh field environments. Once the mass production process is established and the official name is decided, there is a strong possibility that it will be widely adopted as an environmentally friendly and highly durable selling point for next-generation RF lenses,” Digital Camera Life writes.

The publication speculates that Canon’s L Series RF lenses are the likely target for the first commercial test of Dev-02-003, as professional lenses are the most likely to experience harsh environments, such as rain, wind, and dust, and therefore require the most frequent cleaning. These lenses must be extremely resistant to scratches and damage.

Canon has widely publicized environmental and sustainability initiatives, and being the first major lens maker to move beyond potentially hazardous fluorine coatings without any drop in optical quality or performance would be a nice feather in the company’s cap.

Surely, given the rapidly changing PFAS regulations worldwide, Canon is not the only company hard at work to solve the problem. However, it may well be on pace to be the first to do so.

Image creditsCanon, except for the header image, which is an example of the benefits of fluorine coating from Nikon.