Apple has filed for a patent (number 20210041765) for “aperture stop for camera with folded optics” that hint that, as rumored, Apple is working on a “foldable” iPhone.
Admittedly, the patent filing doesn’t mention a foldable phone, just a foldable camera, but one goal of such a camera would obviously be in a foldable/bendable device. In the patent filing, Apple notes that small, mobile multipurpose devices such as smartphones and tablet or pad devices has resulted in a need for high-resolution, small form factor cameras for integration in the devices.
Some small form factor cameras may incorporate optical image stabilization (OIS) mechanisms that may sense and react to external excitation/disturbance by adjusting location of the optical lens on the X and/or Y axis in an attempt to compensate for unwanted motion of the lens. Some small form factor cameras may incorporate an autofocus (AF) mechanism whereby the object focal distance can be adjusted to focus an object plane in front of the camera at an image plane to be captured by the image sensor.
In some such autofocus mechanisms, the optical lens is moved as a single rigid body along the optical axis of the camera to refocus the camera. Apple thinks a camera with foldable optics overcomes the limitations of such mechanisms.
Heres the summary of the patent filing: “Various embodiments include an aperture stop for a camera with folded optics. In some examples, a folded optics arrangement of the camera may include one or more lens elements and one or more light path folding elements (e.g., a prism or a mirror). The aperture stop may be an elongated aperture stop.
“According to various examples, one or more prisms of the folded optics arrangement may have an elongated dimension in the same direction as an elongated dimension of the elongated aperture stop. In some embodiments, the aperture stop may be located between a prism and a lens group of the folded optics arrangement. In some embodiments, the aperture stop may be located proximate an optical element that optically powers a prism of the folded optics arrangement.”