A patent Apple filed in September 2022 has just been approved today, and it showcases a system of shock limiters and dampers to improve camera reliability.
The patent, number 17/951,676, shows a camera enclosure design with a fixed optics system and a movable image sensor enveloped by a voice coil motor. A damper is also attached to the fixed lens optics, designed to absorb an impact between the optics and the moving sensor.
At the heart of the patent is the need to balance high-resolution optics and camera systems on mobile devices, like iPhones, with the genuine possibility of a person dropping or significantly bumping their device against a hard object. Camera systems are exact, requiring near-perfect alignment between image sensor planes and lenses.
“Due to the small form factor of the cameras, however, unintended movements, which may occur when the device is dropped, can cause camera components to collide and become damaged resulting in reduced camera reliability,” Apple’s patent application explains.
Apple’s proposed solution to this risk is, at least from a high-level perspective, to design components for camera systems that can be displaced in response to a sudden impact. The displacement must occur in a controlled, cooperative way, such that multiple components aren’t moved into each other.
For example, suppose a person drops their iPhone on the floor. This is a significant impact, and the force will try to move non-fixed components in similar directions, all else equal. If the optical system, like one with optical image stabilization, pushes lens elements into the image sensor, that’s a significant problem. Instead, if the sensor itself is placed on something that can move in response to external force, the problem can be avoided.
A sensor moving is not a novel concept. Many modern interchangeable lens cameras do this as part of in-body image stabilization systems. These IBIS-equipped cameras shift the image sensor in very precisely controlled ways to counteract camera movement. While one ought not to do this, if a photographer shakes an IBIS-equipped camera with the lens detached, it’s possible to see the sensor moving back and forth.
At first, it may seem that a component moving around could cause more reliability issues, but importantly, if energy has some way to travel through a device, the stress on individual components is significantly reduced. Similar to how racing cars are designed to crumple in specific areas to reduce the force delivered to the driver and dissipate energy, a camera system designed to react in response to force could be less fragile than one built with rigid components.
As with all patents, it’s impossible to determine if or how such a system could be implemented in an actual product. Nonetheless, there’s no doubt that Apple is always looking for ways to improve the performance and reliability of its products, and iPhone photography is a significant part of those efforts.
Image credits: Apple