Foldable cover and display for an electronic device
Electronic devices including a display layer and a cover layer including a foldable region are disclosed herein. The display layer and the cover layer are configured to be moved between a folded configuration and an unfolded configuration by bending the cover layer along the foldable region. Methods of making a cover layer for an electronic device are also disclosed.
1 . An electronic device comprising:
a display layer; and
a cover layer coupled to the display layer, formed from a glass material, and comprising:
a foldable first portion defining a relief feature and a first thickness at the relief feature, the foldable first portion comprising a first exterior compressive stress region having a first depth from an exterior surface of the cover layer;
a second portion defining a second thickness, greater than the first thickness, and comprising a second exterior compressive stress region having a second depth, greater than the first depth, from the exterior surface of the cover layer; and
a third portion, the foldable first portion positioned between the second and the third portions, the third portion having a third thickness, greater than the first thickness and comprising a third exterior compressive stress region having a third depth, greater than the first depth, from the exterior surface of the cover layer, wherein:
the display layer and the cover layer are configured to be moved between a folded configuration and an unfolded configuration by bending the foldable first portion.
2 . The electronic device of claim 1 , wherein:
the foldable first portion of the cover layer defines a bend that spans a width of the cover layer in the folded configuration; and
an interior surface of the cover layer defines an outside of the bend in the folded configuration.
3 . The electronic device of claim 2 , wherein:
the foldable first portion further comprises a first interior compressive stress region having a fourth depth from the interior surface of the cover layer;
the second portion further comprises a second interior compressive stress region having a fifth depth, greater than the fourth depth, from the interior surface of the cover layer; and
the third portion further comprises a third interior compressive stress region having a sixth depth, greater than the fourth depth, from the interior surface of the cover layer.
4 . The electronic device of claim 3 , wherein the relief feature is a recess defined by the interior surface of the cover layer.
5 . The electronic device of claim 3 , further comprising a polymer filler material disposed in the relief feature and optically matched to the cover layer.
6 . The electronic device of claim 3 , wherein:
the glass material is an aluminosilicate glass material;
each of the second exterior compressive stress region, the second interior compressive stress region, the third exterior compressive stress region, and the third interior compressive stress region comprises:
first ions introduced by a first ion exchange operation; and
second ions introduced by a second ion exchange operation; and
each of the first exterior compressive stress region and the first interior compressive stress region comprises the second ions introduced by the second ion exchange operation.
7 . The electronic device of claim 6 , wherein the
the glass material comprises lithium ions;
the first ions are sodium ions; and
the second ions are potassium ions.
8 . An electronic device comprising:
a display layer; and
a cover layer formed from a glass material and coupled to the display layer, the cover layer comprising:
a first portion defining a bend in in a folded configuration of the cover layer and the display layer, the first portion further defining a first thickness and comprising a first exterior compressive stress region having a first depth;
a second portion defining a second thickness, greater than the first thickness, and comprising a second exterior compressive stress region having a second depth, greater than the first depth; and
a third portion, each of the third portion and the second portion partly surrounding the first portion, the third portion defining a third thickness, greater than the first thickness, and the third portion comprising a third exterior compressive stress region having a third depth, greater than the first depth.
9 . The electronic device of claim 8 , wherein:
the first portion of the cover layer further defines a recessed portion of an interior surface of the cover layer; and
the first thickness is defined between an exterior surface and the recessed portion of the interior surface.
10 . The electronic device of claim 9 , wherein the recessed portion of the interior surface at least partially defines an exterior surface of the bend in the folded configuration.
11 . The electronic device of claim 9 , wherein the recessed portion of the interior surface defines a recess depth that is in a range from 20% to 70% of each of the second thickness and the third thickness.
12 . The electronic device of claim 9 , wherein:
the first portion of the cover layer further comprises a first interior compressive stress region having a fourth depth;
the second portion of the cover layer further comprises a second interior compressive stress region having a fifth depth, greater than the fourth depth; and
the third portion of the cover layer further comprises a third interior compressive stress region having a sixth depth, greater than the fourth depth.
13 . The electronic device of claim 12 , wherein:
the second depth of the second exterior compressive stress region and the third depth of the third exterior compressive stress region are a same depth; and
the fifth depth of the second exterior compressive stress region and the sixth depth of the third interior compressive stress region are a same depth.
14 . The electronic device of claim 13 , wherein the first depth of the first exterior compressive stress region and the fourth depth of the first interior compressive stress region are a same depth.
15 . A system comprising:
a cover layer formed from a glass material and comprising:
a first portion defining a bend in a folded configuration of the cover layer, the first portion having a first thickness and comprising:
a first exterior compressive stress region having a first depth from an exterior surface of the cover layer; and
a first interior compressive stress region having a fourth depth from an interior surface of the cover layer;
a second portion having a second thickness, greater than the first thickness, and comprising:
a second exterior compressive stress region having a second depth, greater than the first depth, from the exterior surface; and
a second interior compressive stress region having a fifth depth, greater than the fourth depth from the interior surface; and
a third portion, the first portion positioned between the first and the second portions, the third portion having a third thickness, greater than the first thickness, and comprising:
a third exterior compressive stress region having a third depth, greater than the first depth, from the exterior surface; and
a third interior compressive stress region having a sixth depth, greater than the fourth depth, from the interior surface.
16 . The system of claim 15 , wherein:
the exterior surface of the cover layer defines an interior surface of the bend; and
the interior surface of the cover layer defines a recessed region.
17 . The system of claim 16 , wherein:
the cover layer defines a width and a length that is greater than the width; and
each of the first portion, the second portion, and the third portion spans the width of the cover layer.
18 . The system of claim 16 , wherein each of the first thickness, the second thickness and the third thickness is in a range from 25 micrometers to 400 micrometers.
19 . The system of claim 18 , wherein the second thickness and the third thickness are a same thickness.
20 . The system of claim 15 , wherein:
the exterior surface of the cover layer defines an interior surface of the bend;
the exterior surface of the cover layer defines a recessed region; and
the system further comprises a flexible coating disposed over the recessed region of the exterior surface of the cover layer.