Yesterday the U.S. Patent and Trademark Office officially granted Apple a patent that relates to a new device-to-device communications system. In particular, Apple's granted patent relates to free-space optical communication systems and, more specifically, to systems and methods for dynamically adjusting movable lenses for such systems incorporated into portable electronic devices.

What could such a new communications system provide Apple device users? According to Apple, "A directional free-space optical communication system can facilitate increased data transfer rates (e.g., tens of gigabits per second to terabits per second), increased data transfer privacy, and increased data transfer security relative to conventional device-to-device data communication protocols, such as Wi-Fi, Near-Field Communications, or Bluetooth."

In Apple's patent background, they note that an electronic device can include a free-space optical communication system to wirelessly transmit, receive, or exchange data with another electronic device. In some cases, the optical communication system may be configured to be directional (e.g., line-of-sight) in order to increase data transfer rates, to increase data transfer privacy, or for any other suitable purpose.

However, a conventional directional free-space optical communication system is exceptionally dependent on precise alignment of communicating devices. As such, conventional free-space optical communication systems cannot be incorporated into portable electronic devices that may be moved or repositioned from time to time.

Apple's solution found in granted patent number 11,201,669 involves an apparatus for free-space optical communication in a portable electronic device. The apparatus includes a photosensitive element coupled to a substrate. In many embodiments, the photosensitive element includes at least two separated photosensitive areas. The apparatus also includes a movable lens positioned above the photosensitive element. The apparatus additionally includes a controller configured to adjust a position of the movable lens based on a power output from a first photosensitive area of the photosensitive element and a power output from a second photosensitive area--if any--of the photosensitive element.

In some embodiments, a method of operating a free-space optical communication system with a source device and an endpoint device is described, with the method including the operations of: changing a position of a movable lens positioned over a laser diode in the source device according to a pattern; monitoring power output from a photosensitive area of a photodiode in the endpoint device for a maximum and, in response, sending a signal to the source device to stop changing a position of the source device lens; changing a position of a second movable lens positioned over the photodiode in the endpoint device; and monitoring power output from a photosensitive area of the photodiode for another maximum and, in response, stopping movement of the second movable lens.

In some embodiments, a free-space optical communication system is "directional" in that focused light or laser light emitted from the source device(s) propagates through a medium between the source device(s) and the endpoint device(s) along a substantially line-of-sight path.

A directional free-space optical communication system can facilitate increased data transfer rates (e.g., tens of gigabits per second to terabits per second), increased data transfer privacy, and increased data transfer security relative to conventional device-to-device data communication protocols, such as Wi-Fi, Near-Field Communications, or Bluetooth.

Apple's patent FIG. 1A below depicts a directional free-space optical communication system coupling two electronic devices; FIG. 1B is a simplified system diagram of the directional free-space optical communication system of FIG. 1A.

Apple's patent FIG. 2A below depicts a simplified representation of a source device and an endpoint device, collimated relative to one another; FIG. 4A depicts an endpoint device of a directional free-space optical communication system including a laterally movable lens; FIG. 4B depicts the movable lens of FIG. 4A, shifted in a direction.

For more details, review Apple's granted patent.  

Optical Sensing Engineer Tong Chen is listed as one of the inventors of this patent. Chen has more than 10 years of industrial and academic experience in laser sensing and photonics and is an expert in VCSEL-based optical system design, focusing on depth sensing solutions.