People ask me all the time what might be next in Nikon technology, particularly when it comes to mirrorless. While there is no guarantee that patents become actual products, it's worth delving into the patent stream once and awhile to see what's up, as it sometimes suggests directions a company might be headed.
Nikon's current autofocus system uses phase detect style light masking on every 12th row of pixels. The masking itself appears to be done only in the microlens layer. Nikon has used this system since the Nikon 1 appeared in 2011, and Sony later adopted a version of it.
In a recent Nikon patent, there's a different approach described: every fourth row gets alternating full light capturing Green and masked Green photosites. Only those masked sites use a second, new layer, which filters the light spectrally to form Red light focus data in the fourth row, Blue light focus data in the eighth row.
The changes implied by this patent are multiple. First, the vertical density of focus information is improved (data every fourth row rather than every twelfth). Second, the focus sensors are now seeing different colors of light instead of the same color (alternating Red and Blue instead of just Blue, Blue, Blue). There's more to it than that, but those are the biggest gains I see over the current system. Both these things provide a more useful and subtle data set to the focus processing than the current system, which mostly uses brute force on a ton of long-axis oriented data. Oh, and the detection for this new sensor design is via organic material. I'll leave the rest for others to work out.
Much of the Internet seems to think that Nikon R&D has gone away and that they can't be competitive with Canon and Sony. In doing a deeper dive into recent patents, I'd say that Nikon is still doing as much deep engineering work that's integrated between the Precision and Imaging teams as before, and is still coming up with new and interesting twists like this one.
Can this sensor design go into production? Yes, I'm pretty sure it lies within Nikon's technical capabilities. Moreover, it involves some changes in how the stepper is used at the semiconductor maker, and guess what, Nikon makes steppers.
