Composite of infrared over cables.
The easy answer to this question is: none of them, in the "thermal imaging" sense of the phrase. As of today, no cellular phones of any kind have built-in infrared cameras. Some companies offer accessories which purport to convert a cell phone's camera into a thermal-imaging device, but these offers come with a strong sense of "caveat emptor". However, in January 2011 DARPA, the Defense Advanced Research Projects Agency, announced that it was seeking to integrate today's cellular phones' CMOS camera technology with that of long-wave infrared technology.
DARPA's Project
Unmanned Air-Combat Vehicles: brought to you by DARPA
The DARPA Microsystems Technology Office announced (DARPA-BAA-11-27) in January that the Low-Cost Thermal Imager Manufacturing (LCTI-M) program is working to outfit soldiers on the ground with low-cost infrared cameras for threat-detection and to improve visibility in general. The program's objective is to develop wafer-sized processors for chip-sized thermal imagers. Its vision is to integrate long-wave infrared cameras into cellular phones or into handheld, network-capable devices. Should this technology prevail on the battlefield, it is possible that the new hardware may become diversified and offered on the civilian market.
Apple's IR Patent Scandal
iPhone camera in action
Apple, Inc. has recently revealed a patent whereby it may design a feature for future iPhone versions to detect infrared light. In this way, the company has paved the way for concert venues and movie theaters to stop rampant video recording at their live events. The patent in question describes image-processing circuitry integrated into future iPhone cameras that will be able to scan a photo and collect any infrared light which includes encoded data. The data then is translated into information or commands. In the aforementioned example, infrared light emitted at a venue could signal a phone to disable its camera and prevent further recording.
Other Benefits
Apple's patent filing includes some pros of this proposed infrared scanning technology such as the transmission of data. The technology, once developed, may drive augmented physical space functions. For example, a museum exhibit's supporting information could be accessed remotely. The idea is that the iPhone's ability to receive data would only be limited by the possible places an infrared emitter could be installed.
Conclusion
While IR cell-phone camera technology has yet to hit your local electronics store, it may in the near future.
Tags: cellular phones, infrared cameras, infrared light, camera technology, future iPhone, long-wave infrared