Apple is considering the use of advanced Ultrasonic Touch Sensors on future AirPods & AirPods Max that better perform in Wet Conditions & with Gloves
In February 2021 Patently Apple posted a granted patent report covering ultrasonic proximity sensors used to automatically determine whether AirPods are positioned to provide a desired level of audio performance.
Today the US Patent & Trademark Office published a patent application from Apple that relates to more advanced ultrasonic touch sensors for future versions of AirPods Max and AirPods Pro to better perform in wet conditions and when wearing gloves in the winter.
The use of traditional capacitive touch sensors on AirPods could experience sensing errors when in contact with water, rain, perspiration and when in contact with gloves.
Apple’s patent covers ultrasonic touch sensing capability. In some examples, this ultrasonic touch sensing capability can be integrated into existing device structures to facilitate user input without adding extra structure. Unlike capacitive touch sensing systems, in some ultrasonic touch sensing systems the transducers/electrodes can be implemented far from touch areas, and long-range touch sensing can be achieved (e.g., sonar). Accordingly, when electronics such as antennas are co-located with active touch areas, these ultrasonic systems are less likely to adversely affect those electronics. In addition, ultrasonic touch sensing systems can be less affected when conductive, electrically-floating liquids (e.g., water droplets) or insulated objects (e.g., gloved fingers) come into contact with its touch-sensitive surface.
Ultrasonic touch sensing systems, like other touch sensing systems, can be adversely affected when an object unintentionally makes contact with the touch-sensitive surface, either alone or at the same time as an intended touch. In ultrasonic touch sensing systems, these unintentional contacts can produce reflections of a generated ultrasonic wave, referred to herein as "parasitic" ultrasonic waves or reflections.
When an unintended touch occurs alone (without a simultaneously occurring intended touch), the parasitic reflection caused by the unintended touch can be erroneously interpreted as indicative of an intended, valid touch. When an unintended touch occurs at the same time as an intended touch, the ultrasonic transducers may be unable to distinguish the parasitic reflections from "true" reflections caused by an intended touch (due to the rough "symmetry" of the true and parasitic reflections), and the parasitic reflections can corrupt the proper detection of the valid touch.
Accordingly, some examples in the patent filing are directed to improving the accuracy of ultrasonic touch sensing via the reduction, elimination and/or rejection of parasitic ultrasonic reflections.
Apple’s patent FIG. 1F below illustrates that Apple may one day add Ultrasonic touch sensors to AirPods Max; FIG. 2 illustrates a block diagram of an electronic device including ultrasonic touch sensing and parasitic wave rejection, and in some examples, an additional force sensing system.
Apple’s patent FIG. 16B below illustrates AirPods with an integrated ultrasonic touch and force sensing module located within a cylinder; FIG. 15A illustrates an ultrasonic phased array #1556 formed from transducers (#1510a-1510d) operating in a pulse/echo or TOF configuration in the presence of user finger #1506 and also in the presence of an unintended touching object such as an ear or cheek #1538.
Apple’s patent FIG. 10 above illustrates a cylinder with radial ultrasonic touch sensing.
To review more of the details of Apple's patent application number 20220206630, click here.
Considering that this is a patent application, the timing of such a product to market is unknown at this time.