Years back, Huawei introduced the Mate Xs foldable smartphone with a Fold Out Display form factor as presented in our cover graphic. Since then, Huawei changed course and now sells Fold In foldable smartphones like the Mate X3.

Today the U.S. Patent and Trademark Office officially granted Apple a patent that primarily relates to a Fold Out foldable smartphone design with a focus on its segmented hinge design. The patent also touches on smartphones with a Scrollable and/or Slidable Display.   

Electronic Devices Having Folding & Expandable Displays

Apple's granted patent relates to an electronic device with a foldable display supported by a foldable electronic device housing. First and second portions of the electronic device housing may be joined using hinge structures. The electronic device may have a flexible display such as an organic light-emitting diode (OLED) display. The flexible display may overlap the first housing portion, the hinge structures, and the second housing portion. A flexible supporting layer such as a layer of sheet metal may be used in supporting the display and may overlap the hinge structures.

The hinge structures may include members that are configured to move relative to each other as the hinge structures are bent. In some configurations, hinge structures for the device include gear teeth, belts, and/or other movement synchronization structures. The moving members in the hinge structures may include bars and links with opposing curved bearing surfaces. Stop surfaces may prevent excessive rotation of the bars and links with respect to each other.

The bars and links or other moving members in the hinge structures may rotate relative to each other about virtual pivot points that lie outside of the hinge structures. The pivot points may establish a reduced stress plane (e.g., a neutral stress plane or approximation of a neutral stress plane). The reduced stress plane may lie within the flexible display. This may help reduce stress on the pixels or other brittle layers of the display module as the display is bent.

In some configurations, the hinge structures may include a sliding hinge pin support plate. A hinge pin that passes through the second portion of the housing may be supported by the sliding hinge pin support plate. The hinge pin allows the second portion of the housing to rotate relative to the plate and first housing portion. When the first and second housing portions are folded together, the support plate may slide relative to the first housing portion, thereby moving the hinge pin relative to the first housing portion. This helps to ensure that links in the hinge structures are smoothly wrapped around a curved surface on the second housing surface as the device is folded. A bent portion of the display may rest on an outwardly facing surface of the hinge structures when the display is folded.

Sensors may include force sensors (e.g., strain gauges, capacitive force sensors, resistive force sensors, etc.), audio sensors such as microphones, capacitive touch sensors, capacitive proximity sensors, non-capacitive touch sensors, ultrasonic 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), muscle activity sensors (EMG), heart rate sensors, electrocardiogram sensors, and other biometric sensors, radio-frequency sensors (e.g., radar and other ranging and positioning sensors), humidity sensors, moisture sensors, and/or other sensors.

While 95% of the patent is about a foldable device, Apple decided to add other expandable displays in the form of Sliding Displays and Scrollable Displays as presented below.

Apple notes that device #10 allows the display #14 to be changed in size using sliding motions may also be used. As shown in FIG. 5, for example, the device may be adjusted so that structures in the device and display  slide (in direction #52 or other suitable direction) between a first (unexpanded) configuration in which only the display area is visible.

Apple's patent FIG. 6 above is a side view of a device in an illustrative configuration in which the display #14 is sufficiently flexible to be scrolled. This allows the display to move in and out of housing #12. In an unexpanded configuration, the display is rolled back up and stored in the housing of FIG. 6. In an expanded configuration, the display is enlarged by unscrolling the display in direction #52 and causing the display to extend out of the housing.

Like with most patents, Apple doesn't want their invention to be limited to the focused device of a smartphone. Apple states that their invention could also apply to a TV, MacBook, an iPad, iMac, a gaming device, an Apple Watch and more.

Lastly, although the patent illustrates the display being a Fold Out design, the majority of Apple's foldable patent favor Fold In designs. At the end of the day, Apple could go either way and their protected either way.

To review the full details of this invention, check out granted patent 12213267.