Sony to get rid of mirror for new cameras!

Cool! I don't understand a word of it (the patent text I mean) but Fig 1 and 2 are clearly the outlines of the trusty good old a100. So I wouldn't bet on it coming out very soon, filing the patent doesn't necessarily mean they're also starting up the actual production lines.

dca1213 wrote: I have to admit, I'm a photographer and this is way over my head...

The end result is using the main sensor to do phase detect AF instead of a separate AF module. So we can have EVIL but keep using fast phase detect AF instead of contrast detect AF.

@backToSlr. I was just thinking the same thing.

They have not got rid of the mirror yet so you can still jump in with that patent.

Edited by mpb - 05 February 2010 at 01:37

Seems to me a system like that could be implemented in both SLR and EVIL cameras. Now which one will Sony throw it into, thats a good question...

I must have missed something somewhere but I don't see the addition of phase-detection AF to mean the disappearance of contrast-detection AF and SLR mirrors... Maybe I'm just really thick.

Oops, I stand corrected but my point remains. :)

Edited by pnaciona - 05 February 2010 at 04:34

Its dated Sep. 10th 2009, and the a500/550/450 came out right around then. It might be related to that.

I am reading that sony will be adding an extra pixel site, in addition to the RGB ones, which will be used for AF only. These AF pixels will be dispersed around the sensor, and have 2 films with light slits stacked on top of each other, there is also a second AF pixel right beside it, and each one reads light at a different angle, coming from a micro lens covering them both up. (look at page 6 of the PDF) I guess this gives a steroscopic effect and since there is distance between the two pixels which is then measurements taken to figure out distance.

So...each "pixel" has 2 AF pixels that give measurements of light from a micro lens through two different plates with slits in them, and there are bunch of those AF sites across the sensor that then talk to each other. When the circle of confusion is at its smallest point (most focused image) it locks focus.

They talk about the fact that large apertures have very very narrow depth of field and I guess its one of the big reasons contrast detect fails to focus properly, but with the 2 sensor plates having little slits/pupils the light can still be effectively measured to AF properly, and apparently these pupils can be adjusted either for aperture reasons or available light reasons.



Anyway, I think thats the jist of it. Basically its contrast detect in name only, it seems to be phase detect on a micro level, but embedded into the sensor itself.

Wikipedia phase detect and how it works, and then apply those principles to the diagram on page 6 of the patent, and all the discussion of 2 slits and AF sensors.





Edited by MarkSangenito - 05 February 2010 at 05:56