Apple looking into folded telephoto camera lens system for iPhones

Is Apple planning to make photo accessories for its iPhone line? The company is at least considering it, as evidenced by a new patent filing (number 20200026033) for a “folded telephoto camera lens system.”

In the filing, Apple notes that the advent of small, mobile multipurpose devices such as smartphones has resulted in a need for high-resolution, small form factor cameras for integration in the devices. However, due to limitations of conventional camera technology, conventional small cameras used in such devices tend to capture images at lower resolutions and/or with lower image quality than can be achieved with larger, higher quality cameras. 

Achieving higher resolution with small package size cameras generally requires use of a photosensor with small pixel size and a good, compact imaging lens system. Advances in technology have achieved reduction of the pixel size in photosensors. However, Apple notes that as photosensors become more compact and powerful, demand for compact imaging lens system with improved imaging quality performance has increased. 

Here’s Apple’s summary of the invention: “A folded telephoto lens system may include multiple lenses with refractive power and a light path folding element. Light entering the camera through lens(es) on a first path is refracted to the folding element, which changes direction of the light on to a second path with lens(es) that refract the light to form an image plane at a photosensor. 

“At least one of the object side and image side surfaces of at least one of the lens elements may be aspheric. Total track length (TTL) of the lens system may be 14.0 mm or less. The lens system may be configured so that the telephoto ration (TTL/f) is less than or equal to 1.0. Materials, radii of curvature, shapes, sizes, spacing, and aspheric coefficients of the optical elements may be selected to achieve quality optical performance and high image resolution in a small form factor camera.”