Samsung and multiple Chinese smartphone OEMs are miles ahead of Apple regarding foldable smartphones. A foldable smartphone chart below from CNET shows where foldables are most popular.

 

Marques Brownlee recently posted a review of Huawei’s “tri-fold” smartphone and praised it to no end. While Apple Vision Pro has been criticized for its USD3,500 price tag, Brownlee thought the USD3,500 price of a tri-fold smartphone was justified. So it’s clear that foldables are gaining some steam in the market and will continue to do so as prices fall closer to traditional smartphones like the iPhone 16 Pro Max.

Apple has been working on foldable devices for years in the hopes of getting the hinge and foldable glass just right to avoid heavy fold marks on the display. Today the U.S. Patent Office published a patent application of Apple that focuses on segmented glass for foldable devices.”  

According to Apple, an electronic device may have a display and may be configured to fold about a bend axis that overlaps the display. The display may have a display cover layer with first, second, and third portions that are joined side-by-side and extend laterally across the display. The second portion may have a strip shape that extends along the bend axis and that is configured to bend as the first and third portions are folded towards each other.

The second portion may be formed from a different material than the first and third portions to facilitate bending. For example, the second portion may be formed from a glass with a lower modulus of elasticity than the first and third portions. The second portion may also be thinner than the first and third portions and may be characterized by a compressive surface stress layer that is shallower than compressive surface stress layers in the first and third portions.

As shown in Apple’s patent FIG. 1 below, device #10, which could a foldable iPhone, iPad or MacBook-like device, may have a housing such as housing #12 in which display #14 is mounted. The hinge (#16) may be used to attach first and second portions of the housing together.

The hinge allows the first and second portions (left and right sides) of the housing to rotate with respect to each other about a hinge axis (sometimes referred to as a fold axis or bend axis).

The display may have planar portions such as portions #14A and a bendable portion such as bendable portion #14B that is located between the planar portions. When the device is in an unfolded (planar) configuration, portion #14B is unbent (planar). When the left and right sides of the device are folded together as shown in FIG. 1, portion #14B bends.

To prevent the display cover layer #20 from becoming damaged (e.g., cracking) when the device is folded, the display cover layer may have a strip-shaped bendable portion such as portion #20B that overlaps the hinge and extends along its associated bend axis (see, e.g., bend axis B of FIG. 2, which shows a top view of layer #20). The width of portion 20B orthogonal to bend axis B may be 20 mm, 10-30 mm, 1-50 mm, at least 0.5 mm, less than 60 mm, or other suitable width.

Because portion #20B of layer #20 must bend during folding and unfolding operations as portions #20A are folded towards each other and unfolded away from each other, it is desirable for portion #20B to be highly flexible. Planar portions #20A of display cover layer #20 may be supported by planar portions of the housing and need not be as flexible as bendable portion #20B.

Accordingly, it may be desirable to form portions #20A and #20B of layer #20 using different materials (e.g., different glasses), so that portion 20B is more flexible than portion #20A, using different chemical strengthening treatments (e.g., so that portions #20A are characterized by deeper compressive surface stress than portion #20B), different thicknesses (e.g., so that portion #20B is thinner and therefore more flexible than portion #20A) and/or using other materials, shapes, and processing treatments that allow portion #20B to flex while providing portions #20A with desirable properties such as strong resistance to damage from exposure to contact with sharp objects.

Apple’s patent FIGS. 3 and 4 above are cross-sectional side views of illustrative display cover layers showing how a strip-shaped central portion of a display cover layer may be formed from a different material than laterally adjacent left and right side portions of the display cover layer; FIG. 5 is a cross-sectional side view of an illustrative display cover layer showing how the layer may be chemically strengthened in accordance with an embodiment.

Apple’s latest foldable device patent was initially filed on March 05, 2024 and published today by the U.S. Patent Office. For more details, review patent application 20240370058. 

Other recent foldable device patents: 01, 02, 03, 04 and 05. Many more foldable device patents could found in our Display Archives.