What makes a Carl Zeiss lens so special in a smartphone?

Question

There are smartphones on the market that have a focus towards photography. Some are equipped with a Carl Zeiss lens. I have looked into Wikipedia, which tells me that they are a brand who produces lenses. What makes their lenses so special?

What do you think about a 5MP camera in phones, one which is branded Carl Zeiss, versus another one which isn't? The device I have in mind is the Nokia N900.

Answer

Carl Zeiss is a very well respected lens maker, and very literally one of the reasons "German engineering" conjures images of precision and care. Camera phone manufacturers license the name (and, maybe but not necessarily, actual lens technology) from Zeiss in order to borrow some of that high-end image.

This isn't necessarily all chicanery: companies who are doing this are at least somewhat interested in appearing to be high quality, and the name isn't completely diluted, so you have a reasonable expectation that if the lens says Zeiss, it's probably above run-of-the-mill.

In the case of the N900, the lens is quite good for a smartphone, and more importantly, the sensor is relatively large. 5mpix is a decent resolution for that size of sensor — at this point in the technology, you're not going to get a lot out of having more.

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