iPhone 4 proximity sensor problems blamed on software | iLounge News


iPhone 4 proximity sensor problems blamed on software

Noting that Apple has not responded to numerous complaints in its own support forums regarding iPhone 4 proximity sensor problems, iLounge reader Trent Phillips has conducted tests to determine differences between the sensor behaviors of multiple iPhone models, and concluded that an iOS software update is capable of resolving the problems. In an e-mail to iLounge, Phillips says that the iPhones are all capable of deactivating their screens when objects are detected at a two-inch distance from the sensor, but the iPhone 4 behaves differently from its predecessors, making decisions that lead to accidental screen reactivations under certain conditions.

Earlier iPhones, Phillips notes, switch off their screens at the two-inch distance regardless of the color and past motion of the approaching object. By comparison, the iPhone 4 appears to be less sensitive to dark objects than light ones, and also changes its deactivation distance dynamically after the initial contact. Consequently, the iPhone 4’s screen deactivates only from a shorter distance—say, one inch rather than two inches—if the object it initially reacted to was at the shorter distance. Testing with black and white pieces of paper suggested that the “black piece of paper greatly reduced the detection range of the proximity sensor,” which “could also explain why some people see different effects,” says Phillips, based on skin tone, makeup, light levels, and other factors. His belief is that the iPhone 4’s sensor retains the two-inch range of prior iPhones, but has been miscalibrated on the software side, perhaps in an effort to improve battery life. While it’s still unclear as to whether changes in the iPhone 4’s glass material and/or proximity sensor hardware could also be responsible for the issues, Phillips believes from his testing that a software update could fix the problem, and “all may be well again.”

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All I know is I got a replacement iPhone 4 from apple and my proximity sensor issues went away.  That sounds more like hardware then software to me.

Posted by Gary in East Amherst, NY, USA on July 9, 2010 at 11:28 AM (CDT)


I must be pretty dense because I don’t understand what this problem is, or if my phone has it.

Posted by Usdrowski in East Amherst, NY, USA on July 9, 2010 at 11:53 AM (CDT)


Glad to see Apple cares enough about its customers to ignore it, like with all of the iPhone 4’s problems.

Posted by Matt in East Amherst, NY, USA on July 9, 2010 at 6:44 PM (CDT)


I had mine replaced and the issue went from unbarable to occasionally annoying..I think software tweaks are needed, but that some hardware is also flawed.

Posted by Alex in East Amherst, NY, USA on July 12, 2010 at 12:32 PM (CDT)


I have owned every iPhone since the beginning.  I have definitely experienced both the antenna - signal dropping / call canceling issue, as well as the hyper sensitivity - screen darkening / calibration problem.  During calls, the “mute” mysteriously activates, only to discover that somehow the “mute” button is now illuminated.  Hence, with just a slight shift of the iPhone 4 it reactivates and then any area of the screen being touched becomes operative.  I have had scores of calls “ended” in this fashion.  This is a problem!!!

Posted by Like2SailSD in East Amherst, NY, USA on July 13, 2010 at 2:48 AM (CDT)


My iphone4 seems to darken the screen when you move the phone away from your face. So if I’m talking with it next to my ear, the screen is lit and active. That means I can inadvertently hit mute or end.
If it gets muted, it seems I can’t even cancel the call. The caller may drop off, but it’s over a minute before I can get the screen to work.
Sound like the same problems everyone else is having?
What can I do?

Posted by Dave Holdefer in East Amherst, NY, USA on July 15, 2010 at 10:28 AM (CDT)

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