The Samsung Galaxy Note 5 and S6/S6 edge+ all have the same great primary camera. A camera that proudly holds its first position on DxOMark, and one that was highly praised by phone reviewers all across the web. It seems like the image quality is as good as it gets for those small sensors. But as you thought that it can get any better, Samsung proves us wrong.
That being said, I wonder how much can be improved. The Stacked BSI sensors has shown marginal improvement, but what’s next? I think that the only way to really make a vast improvement in both image quality and better control over depth of field is to use a larger sensor. The problems is that phone manufacturers want to keep the phone profile as slim as possible, and that limits the camera capabilities. Furthermore, larger sensor costs much more to manufacture. So cost and design certainly limit the capabilities of today’s high-end smartphones. I’m sure that many of you ould have liked to have an optical zoom lens with a 1-inch sensor, wouldn’t you?
Take the Nokia 808 PureView smartphone for example. It has a 1/1.2″ (10.67 x 8.0 mm) sensor and image quality that still holds on today. This phone as announced on February 27, 2012. The reason this 2012 phone can still hold its 11th place on DxOMark is due to it’s large sensor. It has 1.4 micron pixels, but the camera can use oversampling (pixel binning) to accommodate for the very high 41MP sensor resolution. There is also the Panasonic Lumix DMC-CM1 smartphone that has a 20MP 1-inch sensor (13.20 x 8.80 mm), even larger than the Nokia one.
The Samsung Galaxy Note5 and Galaxy S6 edge+ (edge plus) rear camera uses a 1/2.6-inch (5.79 mm x 4.01 mm) sensor, which is relatively larger in mobile camera terms, but considerably smaller than the 1/1.2″ and 1″ sensors. Some phone manufacturers like HTC used a lower-resolution sensor, so the pixel are bigger and this helped to improve image quality. But this was done because they didn’t want to use a larger sensor that will make the phone much more expensive. Even for a high-end device, most people just wouldn’t able to afford it.
So what’s next, what improvements we will see in cameras in the Note 6, Note 7 and so forth?. Well, nobody knows for sure. I thought that 1-inch sensor’s price would considerebly drop over the years, and indeed there as a small drop, but the combination of this sensor and optics are relatively very expensive. The Panasonic DMC-CM1 sells for $1000 on Amazon the last time I checked, around $350 more than the Samsung Galaxy S6 Edge (~$650 as of the time of writing).
Flexible polymer lenses ill eventually be present in future smartphones and allow real zoom and adaptable depth-of-field. So these are good news, but in order to have better image quality, we need bigger pixels, and therefore a larger sensor. There are some innovation in this field. Sony curved sensor technology can help improve image quality. It works the same way the human eye works. this technology allows greater light sensitivity and lower noise. This lens design can also use large aperture and overall image quality can be vastly improved. According to Sony, this sensor design can improve center sensitivity by a factor of 1.4.
There is also a new research by Nanyang Technological University in Singapore, allowing to produce sensors that are 1000x more sensitive than current sensors. Those sensor have the ability to detect a broader spectrum of light and well as hold the light-generated electrons for a longer period of time. Hey, that’s not all. According to sciencedaily.com, magnetic sensors are 100 times more sensitive than the silicon equivalent (hat used today). However, that article mentioned that this technology will take about 5 to 10 years before it becomes reality.
I’m pretty sure that will find those sensor technologies continue to improve and be the first to be available in consumer products. Those technologies will reduce the overall production cost and they are preferable to using larger sensors. As I mentioned, the problem is that in mobile imaging, you want to miniaturize the hardware as much as possible and use the latest technologies to achieve this. There are some physic restrictions of course, but ho knows what the future brings.
As for now, the Samsung Galaxy Note5 and S6 Edge+ aren’t innovating over their predecessors, neither does Apple’s latest devices. It might take a few years until we see new type of sensors. As for no, Stacked BSI are the leading technology for camera image sensors.