How iPhone 4's New Camera Sensor Illuminates Low-Light

By Matthew Braga

Back-illuminated sensors technology is making its way into devices like the iPhone, and promising to bring increased low-light performance with it.

Apple has a knack for dropping weird and wonderful technologies into our laps — everything from IPS displays to MEMS gyroscopes, and now, back-illuminated sensors. Don't know what that last one is? You're not alone. The technology, introduced by Sony almost two years ago today, is relatively new, and has found fairly limited thus far. Yet, that's something Apple is looking to change.

iPhone 4's new 5 Megapixel camera, Steve Jobs promised many things, from increased photon collection to pixel maximization — things that sound great on paper, but do little to enlighten the average Joe. What matters is how well the new iPhone performs, and what you can expect from your pictures. There's no doubting that a back-illuminated sensor will produce better pictures than the iPhones of old, but the real question is, by how much?

Note how a back-illuminated sensor leaves all the photons intact. That means a brighter image. 
twice the sensitivity of its traditional CMOS sensors, while Toshiba's implementation produced similar results as well.

In the case of the iPhone 4, the technology should offer a huge improvement in picture quality — perhaps a two-fold increase in brightness compared to previous models, if Sony's tests are any indication. This is huge for low-light shooting, and should make a big difference in terms of video capture as well. 

as CNET points out, a better sensor doesn't necessarily mean a better shooting experience. Image processing could still be slow, even with that beefy A4 chip, and the plastic lens does a lot to degrade your picture's quality. However, there's no doubting some of the photos demoed during today's unveiling were impressive, and real-world performance remains a mystery until the device is in our hands. If image stabilization is included as well — and the possibility is there — we could have one serious camera phone later this month as far as mobile shooting is concerned.    

Images via Apple, Sony.