Apple interested in swappable iPhone camera lenses

The details of Apple's proposed invention were revealed in a new patent filing discovered by AppleInsider and published by the U.S. Patent and Trademark Office on Thursday. The application, entitled "Back Panel for a Portable Electronic Device with Different Camera Lens Options," includes illustrations of an iPhone-like device with the camera located in the same top-left-corner location.

The filing notes that as the quality of digital images taken with highly compact devices increases, users seek even more sophisticated features typically only found with high-end digital cameras, such as digital single reflex (DSLR) cameras. Features such as supplementary lenses and filters, optical zoom, and optical image stabilization are not typically found in multifunction devices that include a camera.

Devices like the iPhone currently come with a pre-assembled digital imaging subsystem that allows them to be highly compact, but does not allow for replaceable lenses. In addition, they do not include a mount for filters or additional lenses.

"It would be desirable to provide a structure for a compact device that allows the end user to reconfigure the optical arrangement of the device while retaining the benefits of assembling the device using a pre-assembled digital imaging subsystem," the filing reads.

Apple's solution is a portable device, like an iPhone, that includes a digital imaging subsystem with a lens that has an optical axis. The device would feature a removable back panel that, when removed, would expose the digital imaging subsystem.

Both the digital imaging subsystem and the removable panel would be held in precise alignment by the iPhone case, which would negate the need for a direct connection between the camera's optical component and the subsystem. This would allow the user to reconfigure the optics of the camera on a highly compact portable device.

Normally, an iPhone camera system would include a near-infrared cut filter to prevent infrared light from reaching the image sensor and distorting the colors of a picture. Apple's system would include the IR-cut filter on the removable panel, which would allow photographers to remove it and capture black-and-white images at very low light levels.

In another potential use, the optical component on an iPhone would feature a close-up lens that would reduce the focal distance and allow for extreme close-up photography. Still another example provided is a lens baffle that could be used with a supplementary lens to increase the focal length of the subsystem and reduce the field of view of an image.

This week's new patent filing is of particular note because Apple co-founder Steve Jobs highlighted photography as one market he wished to reinvent before he passed away late last year. Jobs told biographer Walter Isaacson that he wanted to push more change with cameras, a market where the convenience and quality of iPhone picture taking has already shaken up the digital camera industry.

The proposed invention, published this week, was originally filed by Apple in December of 2010. It is credited to Richard Tsai.