Patterned bonded glass layers in electronic devices
An electronic device may include electrical components and other components mounted within an interior of a housing. The device may have a display on a front face of the device and may have a glass layer that forms a housing wall on a rear face of the device. The glass housing wall may be provided with regions having different appearances. The regions may be textured, may have coatings such as thin-film interference filter coatings formed from stacks of dielectric material having alternating indices of refraction, may have metal coating layers, and/or may have ink coating layers. Textured surfaces, cavities, coatings, and other decoration may be embedded in glass structures that are joined with chemical bonds at diffusion-bonding interfaces.
1. An electronic device having opposing front and rear faces, comprising:
a display on the front face; and
a glass housing wall on the rear face, wherein the glass housing wall is formed from a first layer of glass and a second layer of glass that are joined with chemical bonds at a diffusion-bonding interface, the glass housing wall has first and second regions of first and second different respective appearances, the glass housing wall comprises a coating layer that is embedded between the first and second layers of glass, the coating layer overlaps the first region and does not overlap the second region, and the first layer of glass has a textured glass surface in the first region and a smooth glass surface in the second region.
2. The electronic device defined in claim 1 wherein the coating layer comprises inorganic dielectric.
3. The electronic device defined in claim 1 wherein the coating layer comprises a thin-film interference filter formed from a stack of inorganic dielectric layers.
4. The electronic device defined in claim 1 wherein the coating layer of the first region is configured to form a logo.
5. The electronic device defined in claim 1 further comprising a polymer layer on the glass housing wall that overlaps the first and second regions.
6. The electronic device defined in claim 5 wherein the polymer layer is opaque.
7. The electronic device defined in claim 1 wherein the textured glass surface overlaps the first region and does not overlap the second region.
8. An electronic device having opposing front and rear faces, comprising:
a display on the front face; and
a glass housing wall on the rear face that has an embedded cavity, wherein the glass housing wall is formed from glass portions that are joined with chemical bonds at a diffusion-bonding interface that extends around an entire perimeter of the embedded cavity, the glass portions comprise first and second glass layers, the first glass layer has a textured glass surface formed from protruding surface structures, and the textured glass surface is interposed between the first and second glass layers.
9. The electronic device defined in claim 8 wherein the glass housing wall has first and second regions of first and second different respective appearances and wherein the first region overlaps the embedded cavity.
10. The electronic device defined in claim 9 wherein the glass portions comprise a third glass layer, wherein the second glass layer is interposed between the first and third glass layers and has an opening that forms the embedded cavity, wherein the first and second glass layers are joined with chemical bonds at a first diffusion-bonding interface, and wherein the second and third glass layers are joined with chemical bonds at a second diffusion-bonding interface.
11. The electronic device defined in claim 10 further comprising a coating layer in the embedded cavity.
12. The electronic device defined in claim 11 wherein the coating layer comprises a dielectric stack of inorganic dielectric layers.
13. The electronic device defined in claim 11 wherein the coating layer comprises metal.
14. The electronic device defined in claim 11 wherein the coating layer is configured to form a logo.
15. An electronic device, comprising:
a housing that includes a glass housing wall with embedded decoration, wherein the glass housing wall is formed from glass structures that are joined with chemical bonds at a diffusion-bonding interface, the glass structures comprise first and second glass layers, the first glass layer has a polished surface at the diffusion-bonding interface and a textured glass surface that forms the embedded decoration, and the textured glass surface is formed from protruding surface structures and is interposed between the first and second glass layers; and
electrical components surrounded by the housing.
16. The electronic device defined in claim 15 wherein the glass housing wall has first and second regions of first and second different respective appearances and wherein the first region overlaps the embedded decoration.
17. The electronic device defined in claim 15 wherein the electronic device has opposing front and rear faces, wherein the glass housing wall is on the rear face, and wherein the electronic device further comprises a display on the front face.