The U.S. Patent an Trademark Office has published an Apple patent application which outlines a new system for implementing optical image stabilization (OIS) with improved autofocus (AF) capabilities in a miniature camera, such as those found in iOS devices. The patent backs up recent reports that the next generation iPhone 6 will maintain the 8MP rear camera while focussing on camera technologies such as OIS to improve performance.
Apple’s iPhone 5s introduced last September utilizes software-based image stabalization. This system involves the camera taking four photos in quick succession and then combining the best parts of each photo in order to produce the final image while reducing noise, subject motion and hand shake. Optical image stabilization is hardware-based and allows the actual camera lens to move slightly, reducing the effects of hand shake and other small movements.
The newly published patent application from Apple describes how voice coil motor (VCM) actuators will be utilised to move the camera lens in various directions to provide better optical image stabilization and autofocus:
An embodiment of the invention is an actuator module suitable for use in a camera, more specifically, a miniature camera. The actuator module may include a mechanism to provide an AF function and a mechanism to provide an OIS function. […]
The combination of the AF mechanism and OIS mechanism within a single actuator module allows the actuator module to modify the position of the lens relative to the image sensor along five different axes (i.e., 5 degrees of freedom (DOF)). Representatively, the lens may be shifted or translated along at least three different axes and rotated about at least two different axes.
It is unclear how far Apple has advanced with its OIS/AF system but the patent a patent filing dates suggest that Apple has been working on the technology since early-mid 2012 at least. The patent credits a sole inventor, UK engineer Richard Topliss, who joined Apple in early 2012 after spending over a decade as chief technology officer at Cambridge Mechatronics – a company that focuses on OIS technology for smartphones.