Apple was granted by the U.S. Patent and Trademark Office last Tuesday a patent for their system which allows iPhone's sensors to automatically adjusts the volume of the speakers and detect when to switch from handset to speaker mode depending on the distance of the device from the user.
U.S. Patent No. 8,452,020 for Apple's "Adjustment of acoustic properties based on proximity detection," is a technique where the data from the iPhone's proximity sensor is working to compute the distance from the user, thereby giving the device the capability to automatically adjust its volume.
This capability also covers several sensors, such as passive light sensors and cameras, and of course the infrared sensor which is responsible for turning the multi-touch screen on and off while in a call. Other components can be used as long as it can provide data regarding distance.
As mentioned in the patent, this innovation can automatically adjust the volume depending on the distance of the user from the device. Depending on the chosen output mode, it is applicable to both the speaker and the receiver of the iPhone. On the other hand, the user can set preferences so when the device reaches a particular distance, it will then transition from handset mode to speaker. Apple encourages users to set their profile for the system.
iPhone pioneered the multi-touch no-button technology which led the way to the modern designs of smartphones, the new proximity system is quickly becoming a crucial part of making calls. Apple has had its fair share of system problems, even just recently with the hardware calibration issues of the iPhone 4.
In June 2010, Apple's fourth generation handsets received a lot of user complaints about the proximity sensors, saying that the screen randomly turns the phone's screen on during a call, permitting errant touches on the screen. This was later fixed with a system update to the iOS a few months later.
