Today the US Patent & Trademark Office published a patent application from Apple that relates to force- and/or touch-sensitive input devices having haptic feedback. Alternative input devices, such as touch-input devices, appear to offer some greater flexibility for input scenarios and customization than mechanical keyboards, mice, and similar input devices.

Apple's patent relates to an input device that uses touch and/or force sensing to detect user inputs, and uses haptic outputs to provide feedback to a user. One example of such an input device is a keyboard that does not have mechanical or movable keys. Instead, the keyboard may have a flat, keyless input surface, such as a glass or metal layer, and may include touch and/or force sensing systems to determine when a user touches and/or presses on the surface.

Haptic actuators may provide physical feedback to indicate that a user has pressed the keyless surface with sufficient force to register an input. The haptic actuators may induce a physical sensation that is similar to or representative of a mechanical key. For example, when a user presses the surface of the keyboard with sufficient force, the surface may vibrate or otherwise move to indicate to the user that the intended input has been registered.

Using force sensing in addition to touch sensing may allow a user to use a keyless keyboard more similarly to a mechanical keyboard. For example, when typing, users typically rest multiple fingers on the keyboard. With only touch sensing on a keyless keyboard (e.g., without force sensing), it may be difficult or impossible to determine whether a user is attempting to select a particular key, or whether the user is merely resting a finger on that key. Force sensing, instead of or in addition to touch sensing, allows a keyless keyboard to differentiate between incidental contact and intentional key selections.

Because the keyboard doesn't have mechanical keys, the keyboard may provide numerous other features and functions beyond mere keyboard input. For example, the keyboard may include an adaptive display to render visual information, such as an outline of an input region (e.g., representing a key) and an indication of its function (e.g., a glyph). In this way, the location, size, spacing and/or arrangement of the keys may vary. As another example, the input surface of the keyboard may act as a touch pad to detect touch inputs (e.g., moving a cursor, manipulating user interface elements) as well as typing inputs.

Apple's patent FIG. 14 below depicts an example process of detecting a key press; FIGS. 15A and 15B depict generation of input regions according to user interaction. Users will be able to choose a straight keyboard setup or one that is ergonomically laid out as shown in FIG. 15C.

An input device that includes force sensing, haptic outputs, and an adaptive display may be used to define user interfaces other than traditional keyboards. Apple's patent FIG. 16 below depicts an example input device #1600 incorporated within a notebook or laptop computer in which an alternative user input is produced on an adaptive input surface #1604. The interface supports iTunes / Apple Music; FIG. 17 illustrates virtual keys and a virtual trackpad. While a browser is open on the MacBook, the virtual trackpad is moved higher than normal so as to make it easier to navigate.

Apple's patent FIGS. 18-19 above depict example embodiments of input devices such as an iMac and iPad Pro.

Apple notes that FIG 6B below depicts an example haptic actuator #601 that may produce localized deformations or deflections of a cover display. Apple further notes that the haptic actuator may be configured to retract and/or extend (FIG. 6C) vertically (as illustrated above) to impart tactile outputs.

Apple's patent FIG. 6E above shows us another example arrangement of haptic actuators #601 relative to the cover. In this example, the haptic actuators may be formed from a single sheet or otherwise interconnected via one or more connecting elements #606.

Apple's patent FIGS. 11A-B depict simplified cross-sectional views of a force sensing system, showing example strain gauges.

Below are a few technical points that Apple confirms in their patent claims:

• An input device for an electronic device may include multiple differentiated input regions corresponding to keys of a keyboard; the multiple differentiated input regions are visually differentiated on the top member; the input device is configured to detect a key press of a particular input region by detecting, within a given group of the differentiated input regions, both a touch location and a force value satisfying a force threshold; and the input device further comprises a haptic output system configured to produce a tactile output in response to detecting the key press.

• The haptic output system comprises: a first actuator having a first actuation axis along a first direction; and a second actuator having a second actuation axis along a second direction that is not parallel to the first direction; and the input device is configured to alternate between actuating the first actuator and the second actuator in response to detecting successive key presses.

• A force sensing system for an electronic device, comprising: a cover defining an input surface comprising multiple input regions each corresponding to an input key, the cover configured to locally deform in response to an input force applied to an input region of the multiple input regions; a capacitive sense layer below the cover; a compliant material between the cover and the capacitive sense layer and below the input regions; and a processor electrically coupled to the capacitive sense layer and configured to: determine a force value of the input force based on a change in capacitance between the capacitive sense layer and an input member applied to the input region; and determine a location of the input force based on which of a set of electrodes detected the change in capacitance.

• The force sensing system cover is formed from a glass; the force sensing system is coupled to a lower portion of an enclosure of a notebook computer and is configured as a keyboard for the notebook computer; the multiple input regions are visually differentiated to define a keyboard for the notebook computer; and the notebook computer comprises a display coupled to an upper portion of the enclosure.

• The force sensing system is configured to differentiate between force inputs having centroids about 3.0 cm apart or less.

• In the force sensing system the glass has an elastic modulus in a range of about 60 to about 80 GPa; the glass has a thickness in a range of about 0.1 to about 0.5 mm; and the compliant material has a thickness in a range of about 0.5 mm to about 2.0 mm.

• The force sensing system's compliant material is a foam.

For more details, review Apple's patent application # US 20230015526 A1

A Few of Apple's Inventors

• Alex Lehmann, PE: Product Design Engineer - Finite Element Analyst
• David Chang (Z. H. Zhang): Analog/Mixed Signal Design
• Paul Wang: Senior Manager, Product Design
• Scott McEuen: Product Design Engineering Manager