• The Canon Rumors Forum has officially been shut down as of July 10, 2026.

    All data will be deleted on September 16, 2026.

    the ad free experience will return by July 17, 2026.

Patent: A New Type of ASC Lens Coating

Canon Rumors

Who Dey
Canon Rumors Premium
Jul 20, 2010
12,874
5,707
279,596
Canada
www.canonrumors.com
HTML:
A Canon patent application shows what looks to be expanding on ASC (air sphere coating).</p>
<p>As you can see in the image below, ASC in fact looks like little bubbles</p>
<p><img class="aligncenter size-full wp-image-32722" src="http://www.canonrumors.com/wp-content/uploads/2017/12/JP2017-167271.png" alt="" width="297" height="223" srcset="http://www.canonrumors.com/wp-content/uploads/2017/12/JP2017-167271.png 297w, http://www.canonrumors.com/wp-content/uploads/2017/12/JP2017-167271-225x169.png 225w" sizes="(max-width: 297px) 100vw, 297px" /></p>


<p>From <a href="https://www.canonnews.com/patent-application-for-new-lens-coating">Japan Patent Application</a>: 2017-167271</p>
<blockquote><p>To provide an optical member having an anti-reflection film with high strength, uniform refractive index distribution, and low scattering, and a manufacturing method for the optical member.</p></blockquote>
<span id="pty_trigger"></span>
 
The bubbles in the picture are about 20-30 nm in size. They are much smaller than the wavelength of visible light. I guess this is why they don’t scatter light. Who would have thought this would make a good lens coating? Innovation from Canon.
 
Upvote 0
BeenThere said:
The bubbles in the picture are about 20-30 nm in size. They are much smaller than the wavelength of visible light. I guess this is why they don’t scatter light. Who would have thought this would make a good lens coating? Innovation from Canon.

WOW! interesting. Thanks for the explanation.
 
Upvote 0
As I read the patent, its a manufacturing method, not a new coating. I believe that the existing method for applying the coating is difficult, many complaints have been posted about the coating of the 24-70 F/2.8L II coming loose. This appears to be a improved manufacturing method that may reduce defects or cost less.

OPTICAL MEMBER AND MANUFACTURING METHOD FOR OPTICAL MEMBER
(57)AbstractPROBLEM TO BE SOLVED: To provide an optical member having an anti-reflection film with high strength, uniform refractive index distribution, and low scattering, and a manufacturing method for the optical member.
SOLUTION: A manufacturing method for an optical member includes: a step of applying dispersion liquid containing particles and dispersant on a base material; a step of, after applying the dispersion liquid, applying a solution containing a binder forming component and causing the solution to enter the space between the particles included in the dispersion liquid applied previously, so as to form a single layer having the binder filling the space between the particles; and a step of drying the layer to form an anti-reflection film. The solution contains a silane alkoxy condensate with an average particle diameter of 8 nm or more and 60 nm or less. The solution contains 70 mass% or more of a solvent whose water solubility is 10 wt% or less.
 
Upvote 0
Mt Spokane Photography said:
As I read the patent, its a manufacturing method, not a new coating. I believe that the existing method for applying the coating is difficult, many complaints have been posted about the coating of the 24-70 F/2.8L II coming loose. This appears to be a improved manufacturing method that may reduce defects or cost less.

OPTICAL MEMBER AND MANUFACTURING METHOD FOR OPTICAL MEMBER
(57)AbstractPROBLEM TO BE SOLVED: To provide an optical member having an anti-reflection film with high strength, uniform refractive index distribution, and low scattering, and a manufacturing method for the optical member.
SOLUTION: A manufacturing method for an optical member includes: a step of applying dispersion liquid containing particles and dispersant on a base material; a step of, after applying the dispersion liquid, applying a solution containing a binder forming component and causing the solution to enter the space between the particles included in the dispersion liquid applied previously, so as to form a single layer having the binder filling the space between the particles; and a step of drying the layer to form an anti-reflection film. The solution contains a silane alkoxy condensate with an average particle diameter of 8 nm or more and 60 nm or less. The solution contains 70 mass% or more of a solvent whose water solubility is 10 wt% or less.

it's both. it says so right in the title without even reading further.

OPTICAL MEMBER AND MANUFACTURING METHOD FOR OPTICAL MEMBER

not to mention under problem to be solved:

To provide an optical member having an anti-reflection film with high strength, uniform refractive index distribution, and low scattering,

Usually with canon's element designs, they design both an optical element and also a method of manufacturing. they go hand in hand. as a optical element that is difficult to manufacturer wont' go anywhere.

Also the 24-70 doesn't have ASC coatings. ASC coatings were developed and originally released just a few years ago with the 100-400L II.

Any "coating" that would come loose and be visible or external on the lens and noticeable would be the fluorine coating and entirely different thing all together.
 
Upvote 0