Canon Files Patent for Barndoor-Style Lens Cap Mechanism That Is Permanently Attached

Canon Files Patent for Barndoor-Style Lens Cap Mechanism That Is Permanently Attached

There are two types of photographer: those who utilize their lens cap, and those that don’t. Canon now seems set to make this a thing of the past, as it has patented a barndoor-style lens cap design that folds open when shooting, and shuts to protect the lens when not in use.

As per Japanese Patent Application 2019-113645, the innovative new lens cap design is said to be designed with an aim to ending the attachment and removal of lens caps for good. The patent reads:

The present invention works as a lens hood function at the time of shooting and as a lens protection function at the time of non-shooting, thus eliminating the need for lens cap attachment/removal and barrier opening/closing operations.

It’s early days yet, but the idea would mean never losing a lens cap again, given that this design would be permanently affixed to the lens. However, whether it’s quite as air-tight and can prevent dust, dirt, and moisture from getting through remains to be seen. There’s also the concern that the design would eliminate the chance of using attachable filters in front of the camera.

The designs featured in the patent application also appear to signify that the proposed barndoor-style lens cap would only work with lenses that have extending barrels. It seems internal zoom/focus lenses wouldn’t work with this design.

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A 28-year-old self-taught photographer, Jack Alexander specialises in intimate portraits with musicians, actors, and models.

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17 Comments

This is one of the weirder ideas I've seen come out of Canon... On the one hand, it seems cool because you'll never lose your lens cap and it essentially doubles as a lens hood. On the other hand, it looks like more things that can break, collect crud, and something that can potentially be knocked in the way of the lens by some random passerby while you're photographing.

Yeah, my first thought is more moving parts = more places for things to get broken. That's why I always hated pop up headlights no matter how cool they looked

It would only double as a lens hood if it completely surrounds the whole front of the lens. In that paten drawing it looks like it leaves gaps between each door where light could leak in.

This feels like one of those times where a company patents an idea but has no real intention of actually using it.

Would be nice if the whole assembly is detachable.

Can they create barndoors that wrap around the entire camera when not in use?

Hey, your barn door is open.

That looks like a horrible idea...not being able to remove it would drive me nutty.

Phew. Glad they’ve filed for a patent on this. Means it’s very unlikely Nikon will inflict that upon us.

Unlikely Canon will, either. If I remember correctly, they hold the third most patents in the U.S. I’m sure they have lots of things patented that will never see a production line.

This is just patent trolling plain and simple.

Canon innovating in the lens cap space.
Nobody asked for this.

It's not innovating when the idea has already been done by several manufacturers over the decades.

For the extra lazy. Or the extra rich. Or both.

As often as I misplace my lens cap on shoots I don't like this idea. Too much of a risk of something getting stuck or going wrong in general. And I personally wonder how you will get it open without at least chancing a fingerprint on the lens

Nothing new. Leica / Panasonic offered more or less the same thing for the D-Lux / LX100 range.

This is nothing new. Panasonic makes this exact lens cap for the LX100.

How can they get a patent for something that has already existed for decades? Has Canon really reduced themselves to patent trolling and crowdfunding to try and stay relevant?