Apple's engineers have been working on new finger-mounted devices for a number of year now and we've covered a few of Apple's previous patents in this field (01 02 & 03). Today the U.S. Patent and Trademark Office officially granted Apple a patent that relates to future finger-mounted devices titled "Systems for calibrating finger devices."

In Apple's patent background they noted that electronic devices such as computers can be controlled using computer mice and other input accessories. Input accessories can be used to control content that is displayed on a display and to take other actions. Some input accessories for computer systems may be cumbersome, uncomfortable, or unable to accommodate different users.

Apple's granted patent covers a system that may include a finger device that has sensor circuitry in its housing. The sensor circuitry may include a strain gauge, accelerometer, displacement sensor, and/or other sensor circuitry to detect finger input as the housing is moved by the finger. Wireless communications circuitry may be used to supply the finger input to other devices in the system such as a head-mounted device or other electronic device. During operation, finger input may be used to manipulate content displayed by the head-mounted device or other equipment in the system.

Electronic devices that are configured to be mounted on the body of a user may be used to gather user input and to provide a user with output. For example, electronic devices that are configured to be worn on one or more of a user's fingers, which are sometimes referred to as finger devices or finger-mounted devices, may be used to gather user input and to supply output.

A finger device may, as an example, include an inertial measurement unit with an accelerometer for gathering information on figure motions such as finger taps or free-space  (in-air) finger gestures, may include force sensors for gathering information on normal and shear forces in the finger device and the user's finger, may include a displacement sensor, force sensor, or other sensor for measuring movements of the sides of the finger as the finger contacts an external surface, and may include other sensors for gathering information on the interactions between the finger device (and the user's finger on which the device is mounted) and the surrounding environment.

The finger device may include a haptic output device to provide the user's finger with haptic output and may include other output components.

One or more finger devices may gather user input from a user. The user may use finger devices in operating electronic devices. For example, a finger device may be used as a controller for a virtual reality or mixed reality device (e.g., head-mounted equipment such as glasses, goggles, a helmet, or other device with a display).

Apple also notes that these finger devices could also one day be used in relation to smart contact lenses, a heads-up display, vehicles with smart windshields and other projection systems, iDevices and Macs.  

The user input may be used in controlling visual output on the display. Corresponding haptic output may be provided to the user's fingers using the finger devices. Haptic output may be used, for example, to provide the fingers of a user with a desired texture sensation as a user is touching a real object or as a user is touching a virtual object. Haptic output can also be used to create detents and other haptic effects.

Finger devices can be worn on any or all of a user's fingers (e.g., the index finger, the index finger and thumb, three of a user's fingers on one of the user's hands, some or all fingers on both hands, etc.). To enhance the sensitivity of a user's touch as the user interacts with surrounding objects, finger devices may have inverted U shapes or other configurations that allow the finger devices to be worn over the top and sides of a user's finger tips while leaving the user's finger pads exposed. This allows a user to touch objects with the finger pad portions of the user's fingers during use.

Apple's patent FIG. 2 below is a top view of a user's finger (finger #40) and an illustrative finger-mounted device #10. As shown in FIG. 2, the device may be formed from a finger-mounted unit that is mounted on or near the tip of finger (e.g., partly or completely overlapping fingernail #42). If desired, the device may be worn elsewhere on a user's fingers such as over a knuckle. A user could wear one or multiple finger devices simultaneously.

In Apple's patent FIG. 7 below, we're able to see a finger applying force in direction #52 towards a force sensor located on an electronic device (iPhone, Apple Watch, iPad, Macs).

As the user's finger applies force on force sensor #66, sensors #18 may measure displacement of the sides of the finger (e.g., changes in distance between the membrane and sensor #18 as the sides of the finger are pressed outwardly in directions #54) while the sensor measures the force in direction #52.

Apple's patent FIG. 14 above is a side view of an illustrative system for calibrating a finger device based on captured images from a camera; FIG. 15 is a flow chart of illustrative steps involved in calibrating a finger device using an external electronic device.

Last week Patently Apple posted a patent report that covered Apple's next-gen force sensors designed for small form factors and directly relates to today's invention.

For more details, review Apple's granted patent 11,287,886