Apple is exploring a system that would automatically block speaker and microphone ports to protect them from liquids and other contaminants when not in use.
Apple made its iPhone 6S water resistant by covering its logic board in silicon. That measure targeted components that are highly sensitive to water damage, rather than waterproofing the entire case. The technique, of course, was patented by Apple.
Now the company has filed a new patent application that could see a different but equally targeted method for protecting other iPhone components, such as speakers, microphone and anything that sits behind a port in the device's casing.
The patent filing, published on Thursday, describes a new shutter system placed on the inside of an iPhone's housing to protect audio and other electronic components that might be exposed to the elements through port openings.
The shutter could be placed between the audio component and the housing port, and would be moulded to mirror any openings in a device's housing, or could simply be a plate-like design to cover the port.
On an iPhone 6, for example, the shutters could be built to exactly cover the headphone port or the openings for the speaker on the bottom of the device.
"The shutter may be closed by placing the shutter member in a position in which the housing openings are blocked, thereby preventing intrusion of contaminants into the interior portion of the housing," Apple notes.
"The shutter may be opened by placing the shutter member in a position in which the housing openings are unblocked, thereby allowing sound to pass through the housing port."
Apple primarily envisages that the shutter would be automated to prevent moisture and dirt from entering the device, with the system monitoring for events such as audio playback to indicate when to open the shutter.
However, it also notes the shutters could be manually opened or closed or it could make the electronic controller responsive to open and close commands.
Of course, the iPhone isn't the only Apple device with port openings for electronic components and Apple notes other applications for the shutter system could include PCs, laptops, TVs, wearable devices, headphones, displays and media players.