Today the U.S. Patent and Trademark Office officially published a patent application from Apple that relates to a future foldable device, like a laptop, having a new optical angle sensor replacing today's magnet-based sensors.  Further, this future laptop would have a touch display that could extend through to the bottom half of the device to provide a virtual-like keyboard, trackpad and buttons.

Electronic Device With Optical Angle Sensor

Apple's invention covers an electronic device provided with first and second housing portions that can rotate relative to each other about a hinge. Apple later points to the device being a form of foldable laptop with new Optical Angle sensors that would replace today's magnetic angle sensors  which are susceptible to magnetic fields from static magnets, which can be found in many electronic devices. 

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Apple's patent FIG. 1 above illustrates the new Optical Angle Sensor being implanted in future MacBooks. Another major aspect of the patent is its admission that display #14 would include a two-dimensional capacitive touch sensor integrated into display #14.

Further to FIG. 1, Apple notes that if desired, sensors #16 may include optical sensors such as optical sensors that emit and detect light, ultrasonic sensors, optical touch sensors, optical proximity sensors, and/or other touch sensors and/or proximity sensors, monochromatic and color ambient light sensors, image sensors, fingerprint sensors, temperature sensors, sensors for measuring three-dimensional non-contact gestures (“air gestures”), pressure sensors, sensors for detecting position, orientation, and/or motion (e.g., accelerometers, magnetic sensors such as compass sensors, gyroscopes, and/or inertial measurement units that contain some or all of these sensors), health sensors, radio-frequency sensors, depth sensors (e.g., structured light sensors and/or depth sensors based on stereo imaging devices that capture three-dimensional images), optical sensors such as self-mixing sensors and light detection and ranging (lidar) sensors that gather time-of-flight measurements, humidity sensors, moisture sensors, gaze tracking sensors, and/or other sensors. In accordance with some embodiments, sensors 16 can include an optical sensor 26 configured to measure a hinge angle between two housing portions that rotate relative to each other about a hinge. Such type of sensor that uses light to measure the hinge angle is sometimes referred to as an optical angle sensor or an optical hinge angle sensor #26.

Without confirming outright that portion 12-1 of device 10 above provides a virtual keyboard, Apple in a round about way describes device #10 having other input-output devices to gather user input. For example, buttons may be used to gather button press input, touch sensors overlapping displays can be used for gathering user touch screen input, touch pads may be used in gathering touch input, microphones may be used for gathering audio input, accelerometers may be used in monitoring when a finger contacts an input surface and may therefore be used to gather finger press input, etc.  

Although the patent's emphasis is placed on Device #10 being a new bendable-type laptop, the "hinge device" could also apply to an bendable/foldable iPhone or iPad according to patent point #0025. 

The patent further describes an aspect of the patent wherein the electronic device can further include a hinge angle encoding structure disposed on the hinge, an emitter configured to emit light towards the hinge angle encoding structure, a sensor die configured to receive the light reflecting back from the hinge angle encoding structure, and a polarizing filter layer disposed on the sensor die. The hinge angle encoding structure can include an additional polarizing filter layer and a reflective diffuser layer interposed between the additional polarizing filter layer and the hinge. The additional polarizing filter layer can be a linear polarizer or an absorptive polarizer.

The hinge angle encoding structure can be a reflective polarizer. The hinge angle encoding structure can include an additional polarizing filter layer and a specular reflector layer interposed between the additional polarizing filter layer and the hinge. The polarizing filter layer can be a pixelated polarizer. The emitter can optionally be stacked on the sensor die. The emitter and sensor die can be housed within a sensor assembly cap having a mid-wall separating the sensor die and the emitter.

An aspect of the patent provides a method of operating an optical hinge angle sensor in the electronic device. The method can include using an emitter to emit light towards a hinge angle encoding structure on the hinge, using a polarizing filter layer to polarize the light reflecting back from the hinge angle encoding structure, using a sensor die to sense polarized light traversing the polarizing filter layer and outputting one or more intensity values, and computing an angle at which the plurality of housing portions are rotated about the hinge based on the one or more intensity values. Computing the angle can involve converting the intensity values to corresponding sine and cosine bases, performing gain and offset correction on the sine and cosine bases, filtering the sine and cosine bases, and/or computing an arctangent function using the sine and cosine bases.

Lastly, Apple notes that the housing of the described laptop or iDevice could be made of glass, ceramics, fiber composites, stainless steel, aluminum, plastic or a combination of any two or more of these materials.  

To review the full details of this invention, check out patent application 20240247929.

For the record: Apple confirmed back in 2021 that one of their foldable devices would be a laptop.