Patent for Moving Sensor Switch?

[Canon Rumors]

<a href="http://www.canonrumors.com/wp-content/uploads/2016/01/mirrorless-slr.gif" rel="attachment wp-att-24206"><img class="aligncenter size-full wp-image-24206" src="http://www.canonrumors.com/wp-content/uploads/2016/01/mirrorless-slr.gif" alt="mirrorless-slr" width="560" height="326" /></a></p>
<p>A patent that seems to show a switch that will move a camera from mirorrless to DSLR mode has been published.</p>
<p><a href="http://www.northlight-images.co.uk/cameras/Canon_rumours.html" target="_blank">Keith over at Northlight</a> provided the animation above and this explanation:</p>
<blockquote><p>Short back focus lenses such as EF-M allow you to put the sensor much closer to the lens, reducing body depth. However, unless you choose an EVF, there is no way to get a good optical reflex viewfinder. The patent allows you to swap between a focus screen or sensor close up to the lens.</p>
<p>Perhaps a bit clearer to see in this animation of the short backfocus reflex viewfinder design. The sensor is red and the focus screen green (other moving part is a mirror) This allows a reflex optical viewfinder to be used with any short backfocus lens.</p></blockquote>
<p>A very interesting concept indeed.</p>
<span id="pty_trigger"></span>

 

[3kramd5]

Seems like a neat way to get the worst of both worlds in one package!

 

[gruhl28]

Seems like a neat way to get the worst of both worlds in one package!

LOL, exactly.

If I'm understanding correctly, this would allow you to use lenses designed for mirrorless cameras on a DSLR. Why would you want to do that? I guess maybe someone wants to use Leica M lenses on a DSLR? Or use mostly mirrorless lenses with a mirrorless camera, but also have a DSLR that works with those lenses for times when a DSLR is an advantage? How large a market would that be?

 

[TeT]

This is something else. Probably just covering a concept that they garnered something useful from. Practical application (from marketing sales angle) of the diagram displayed doesn't make much sense.

 

[chmteacher]

Seems like a neat way to get the worst of both worlds in one package!

HAHAHAH!

 

[bseitz234]

If this makes it so I can have a wide-ish, fast enough prime for an APS-C sensor (mount the EF-M 22mm f/2 on my 7D), short of shelling out for the 24L, then I guess I see a purpose in it. Then again, is it really worth all the effort to make a moveable sensor so I have access to one more $200 lens? Doubtful...

 

[Luds34]

Seems like a neat way to get the worst of both worlds in one package!

I was kind of thinking the same, seems like a very compromising solution, especially if we are talking M size, APS-C type of camera. And for what? To get an OVF? I think most would take the compromise of an EVF on an M to be able to maintain the small form factor.

 

[-1]

Now we know what Canon's gonna release 1/4! ヅ

 

[skp]

There has to be more to this. As shown, it seems that in order to take a photo while in OVF mode, three things would have to move 1) the focusing screen, 2) the mirror, and 3) the sensor itself. I'm not sure, but it seems that having to move all three things would probably create such a lag before the image is captured that it might defeat the advantage of the OVF. More importantly, it seems like flapping the entire image sensor into place would introduce a vibration problem millions of times worse than the mirror slap issue that engineers have fought to dampen over countless generations of DSLRs.

Based on what we've seen and heard over the past couple of years since mirrorless started taking off, I have no doubt that Canon is working one something interesting to overcome the deficiencies of electronic viewfinders in a mirrorless body, but this isn't the whole picture. Canon isn't that daft.

 

[Click]

Seems like a neat way to get the worst of both worlds in one package!

LOL

 

[scrup]

DOA,

technology is about less moving parts not more.

Work on EVF, Improved processing and Battery Life.

The mirror is not the future.

 

[Nininini]

this would allow you to use lenses designed for mirrorless cameras on a DSLR. Why would you want to do that?

smaller flange distance would simplify lens design and reduce size

for canon it would also mean they no longer need to design 2 types of lenses, they are now being forced to design lenses for mirrorless and DSLR, that's a crazy extra cost for them that they are sure to find a solution for in the future

this isn't a weird solution at all, anyone who has given flange distance a second of thought quickly realizes that the only way to reduce the flange distance is to physically move the sensor when pressing the shutter, the mirror in DSLR takes up the spot where the sensor is in mirrorless

letting the sensor flap just like the mirror is not a new idea, I've seen several people mention it in the past

 

[rs]

This is a concept well suited to a company with a large back catalogue of mirrorless lenses that wants to move into the DSLR/OVF market, and doesn't want to start from scratch with lenses.

Canon doesn't fit that description.

 

[Nininini]

technology is about less moving parts not more.

Not always true, one example is tray loading CD players VS slot loading.

Tray loading has much more mechanical parts, a bigger motor, more parts...yet, it is far more reliable than slot loading, the disc can't get stuck, the disc has far less chance to get scratched. Slot loading has less moving parts, but it never took off, some brands like Apple use it, but it never displaced tray loading, tray loading is still far more popular, it is far more reliable.

EVF have a major issue, they use a lot of battery life.

 

[Bernard]

There has to be more to this. As shown, it seems that in order to take a photo while in OVF mode, three things would have to move (...)

They would be geared together to move as one, and they could also balance each other to minimize vibration, so it's not an un-solvable problem.

The illustration may be confusing. I imagine that the mirror and focusing screen would move as one (collapsing?) unit.

 

[Steve_FR]

I am in agreement that this patent looks at first glance like a ridiculous Rube Goldberg contraption, but it could also be one of the most exciting recent patents from Canon.

It appears to have an EF-M focal flange distance (18mm) That would allow a DSLR with this design to use all legacy Canon FD lenses with an adapter. As well as most other legacy glass. Potentially there could also be room for a full frame sensor, and built in sensor stabilization. That's a bit of a stretch, but...if the sensor is already moving, maybe it could compensation for hand-held vibration as well. Could be a really exciting camera. EF-M lenses could be used in "APS-C" mode, and this could open up the doors for full frame EF-M lenses without adding another lens mount type to the lineup.

 

[Wizardly]

Some patents you file to build. Some you file to license. Some you file to block a build.

I'm guessing this is for license.

 

[Tugela]

Seems like a neat way to get the worst of both worlds in one package!

Not practical, since it would significantly change the optical path length. You would need completely different lenses for each mode.

 

[Loswr]

Not practical, since it would significantly change the optical path length. You would need completely different lenses for each mode.

In current dSLRs, the optical path length to the eyepiece is significantly different from that to the image sensor, yet somehow I can still both look through the lens via the viewfinder and capture an image with the sensor, all with the same lens. Why?

Beacuse the the focusing screen is at the same relative location in the optical path as the sensor. That's also true in the animation that Keith at Northlight prepared (from the diagrams in the patent) to illustrate the concept.

The concept is perfectly valid, but your understanding of it and the relevant underlying principles seems to be lacking.

 

[Tugela]

Not practical, since it would significantly change the optical path length. You would need completely different lenses for each mode.

In current dSLRs, the optical path length to the eyepiece is significantly different from that to the image sensor, yet somehow I can still both look through the lens via the viewfinder and capture an image with the sensor, all with the same lens. Why?

Beacuse the the focusing screen is at the same relative location in the optical path as the sensor. That's also true in the animation that Keith at Northlight prepared (from the diagrams in the patent) to illustrate the concept.

The concept is perfectly valid, but your understanding of it and the relevant underlying principles seems to be lacking.

The only understanding lacking is yours.

Because the mirror has its own optics to correct for the changes in optical path lens. The sensor doesn't move, so for the purposes of taking a picture no additional correction is needed. If your sensor moves and changes the optical path lens, you will also have to flip in additional optics to correct for that, if you are using the same lens. That is not practical. Realistically you would need to use a completely different lens design.