LASER CUT GLASS SHEETS FOR ELECTRICALLY CONTROLLABLE OPTICALLY ACTIVE STRUCTURES

20240198458

18/542442

December 15, 2023

A multilayer glass panel may be cut using a laser cutting technique. In some examples, the technique involves directing a laser beam into to panel to form a separation line. The separation line includes a plurality of spaced-apart defect columns extending at least partially through a first glass substrate but not through a second glass substrate. The plurality of spaced-apart defect columns each include a plurality of spaced-apart filamentation flaws. The example method can also involve separating a portion of the first glass substrate from the second glass substrate along the separation line to thereby configure the multilayer panel with a shelf defined by a portion of the second glass substrate extending outwardly from the separation line.

1. A method of laser cutting a multilayer glass panel, the method comprising: directing a laser beam into a multilayer panel that comprises a first glass substrate joined to a second glass substrate, wherein directing the laser beam into the multilayer panel comprises forming a separation line comprising a plurality of spaced-apart defect columns extending at least partially through the first glass substrate but not through the second glass substrate, each of the plurality of spaced-apart defect columns comprising a plurality of spaced-apart filamentation flaws; and separating a portion of the first glass substrate from the second glass substrate along the separation line to thereby configure the multilayer panel with a shelf defined by a portion of the second glass substrate extending outwardly from the separation line.

2. The method of claim 1, wherein each of the plurality of spaced-apart defect columns has a width within a range from 0.1 mm to 1.0 mm.

3. The method of claim 1, wherein a distance separating each of the plurality of spaced-apart defect columns from an adjacent one of the plurality of spaced-apart defect columns is within a range from 0.1 mm to 1.0 mm.

4. The method of claim 3, wherein the distance separating each of the plurality of spaced-apart defect columns from the adjacent one of the plurality of spaced-apart defect columns is substantially constant across a length of the separation line.

5. The method of claim 3, wherein the distance separating each of the plurality of spaced-apart defect columns from the adjacent one of the plurality of spaced-apart defect columns varies across a length of the separation line.

6. The method of claim 1, wherein: the plurality of spaced-apart defect columns have a combined width along the length of the separation line; the multilayer panel defines regions devoid of laser-induced defects between the plurality of spaced-apart defect columns, the regions devoid of laser-induced defects having a combined width along the length of the separation line; and a ratio of the combined width of the regions devoid of laser-induced defects divided by the combined width of the plurality of spaced-apart defect columns is within a range from 5:1 to 1:5.

7. The method of claim 1, wherein: each of the plurality of spaced-apart filamentation flaws has a width within a range from 0.0005 mm to 0.0025 mm; and a distance separating each of the plurality of spaced-apart filamentation flaws from an adjacent one of the plurality of spaced-apart filamentation flaws is within a range from 0.001 mm to 0.01 mm.

8. The method of claim 1, wherein directing the laser beam into the multilayer panel comprises generating an induced absorption within the first glass substrate that produces each of the plurality of spaced-apart filamentation flaws.

9. The method of claim 1, wherein directing the laser beam into the multilayer panel comprises directing a pulsed laser beam at the multilayer panel.

10. The method of claim 1, wherein: the first glass substrate has an inner face and an outer face; the second glass substrate has an inner face and an outer face; the inner face of the first glass substrate is joined to the inner face of the second glass substrate; and directing the laser beam into the multilayer panel comprises directing the laser beam through the outer face of the first glass substrate toward the inner face of the second glass substrate.

11. The method of claim 1, wherein: the first glass substrate has an inner face and an outer face; the second glass substrate has an inner face and an outer face; the inner face of the first glass substrate carries a first electrically conductive layer; the inner face of the second glass substrate carries a second electrically conductive layer; and an electrically controllable optically active material is positioned between the first electrically conductive layer and the second electrically conductive layer.

12. The method of claim 11, wherein forming the separation line comprising the plurality of spaced-apart defect columns extending at least partially through the first glass substrate but not through the second glass substrate comprises electrically deactivating regions of the second electrically conductive layer aligned with each of the plurality of spaced-apart defect columns while maintaining electrical conductivity of the second electrically conductive layer in regions between the plurality of spaced-apart defect columns.

13. The method of claim 12, further comprising, attaching an electrode to the shelf defined by the portion of the second glass substrate extending outwardly from the separation line.

14. The method of claim 11, wherein the multilayer panel comprises a sealant bounding the electrically controllable optically active material, the sealant joining the inner face of the first glass substrate to the inner face of the second glass substrate.

15. The method of claim 11, wherein the electrically controllable optically active material is a liquid crystal material.

16. The method of claim 1, wherein forming the separation line comprising the plurality of spaced-apart defect columns extending at least partially through the first glass substrate but not through the second glass substrate comprises forming the plurality of spaced-apart defect columns having a length extending through an entire thickness of the first glass substrate and to a depth less than 0.5 mm below the inner face of the second glass substrate.

17. The method of claim 1, further comprising, after directing the laser beam into the multilayer panel and forming the separation line comprising the plurality of spaced-apart defect columns, directing a second laser beam across the separation line to form a plurality of secondary spaced-apart filamentation flaws extending partially but not fully through a thickness of the first glass substrate.

18. The method of claim 17, wherein the first glass substrate has an inner face and an outer face, and the secondary spaced-apart filamentation flaws extend to a depth less than 0.8 mm above the inner face of the first glass substrate.

19. The method of claim 17, wherein: directing the laser beam into the multilayer panel and forming the separation line comprising the plurality of spaced-apart defect columns comprises forming regions of the first glass substrate devoid of laser-induced defects between the plurality of spaced-apart defect columns; and directing the second laser beam across the separation line to form the plurality of secondary spaced-apart filamentation flaws comprises forming the secondary spaced-apart filamentation flaws over both the spaced-apart defect columns and the regions of the first glass substrate devoid of laser-induced defects.

20. The method of claim 17, wherein a distance separating each of the plurality of secondary spaced-apart filamentation flaws from an adjacent one of the plurality of secondary spaced-apart filamentation flaws is less than 1.0 mm.

21. The method of claim 17, wherein the plurality of secondary spaced-apart filamentation flaws extend across an entire length of the separation line.

22. The method of claim 1, wherein directing the laser beam into the multilayer panel comprises directing the laser beam into the multilayer panel from a first thickness direction and on a first lengthwise or widthwise side of the multilayer panel, and further comprising: directing the laser beam into the multilayer panel from a second thickness direction and on a second lengthwise or widthwise side of the multilayer panel, wherein directing the laser beam into the multilayer panel from the second thickness direction comprises forming a second separation line comprising a second plurality of spaced-apart defect columns extending at least partially through the second glass substrate but not through the first glass substrate, each of the second plurality of spaced-apart defect columns comprising a second plurality of spaced-apart filamentation flaws; and separating a portion of the second glass substrate from the first glass substrate along the second separation line to thereby configure the multilayer panel with a second shelf defined by a portion of the first glass substrate extending outwardly from the second separation line.

23. The method of claim 1, wherein separating the portion of the first glass substrate from the second glass substrate along the separation line comprises applying a mechanically and/or thermally induced force to propagate a crack along the separation line through each of the plurality of spaced-apart defect columns.

24. An electrically controllable optically active structure, the structure comprising: a first glass substrate having an inner face and an outer face; a second glass substrate having an inner face and an outer face, the second glass substrate being joined to the first glass substrate with the inner face of the first glass substrate facing the inner face of the second glass substrate; an electrically controllable optically active material positioned between the inner face of the first glass substrate and the inner face of the second glass substrate; and a first electrically conductive layer carried by the inner face of the first glass substrate and a second electrically conductive layer carried by the inner face of the second glass substrate, and the first electrically conductive layer and the second electrically conductive layer being arranged to electrically control the electrically controllable optically active material; wherein the first glass substrate, the second glass substrate, and the electrically controllable optically active material define a multilayer panel having a first side edge and a second side edge; the first side edge defines a first shelf comprising a portion of the second glass substrate extending outwardly from a cut edge of the first glass substrate, the cut edge of the first glass substrate having a plurality of spaced-apart defect columns extending at least partially through the first glass substrate but not through the second glass substrate, each of the plurality of spaced-apart defect columns comprising a plurality of spaced-apart filamentation flaws; and the second side edge defines a second shelf comprising a portion of the first glass substrate extending outwardly from a cut edge of the second glass substrate, the cut edge of the second glass substrate having a plurality of spaced-apart defect columns extending at least partially through the second glass substrate but not through the second glass substrate, each of the plurality of spaced-apart defect columns comprising a plurality of spaced-apart filamentation flaws.

25. The structure of claim 24, wherein: the second electrically conductive layer extends over the first shelf, and the second electrically conductive layer is electrically deactivated under the plurality of spaced-apart defect columns on the cut edge of the first glass substrate but electrically conductive in regions between the plurality of spaced-apart defect columns; and the first electrically conductive layer extends over the second shelf, and the first electrically conductive layer is electrically deactivated under the plurality of spaced-apart defect columns on the cut edge of the second glass substrate but electrically conductive in regions between the plurality of spaced-apart defect columns.

26. The structure of claim 25, further comprising: a first electrode electrically connected to the second electrically conductive layer through regions of the second electrically conductive layer between the plurality of spaced-apart defect columns on the first shelf; and a second electrode electrically connected to the first electrically conductive layer through regions of the first electrically conductive layer between the plurality of spaced-apart defect columns on the second.

27. The structure of claim 24, wherein: each of the plurality of spaced-apart defect columns on the cut edge of the first glass substrate and on the cut edge of the second glass substrate each has a width within a range from 0.1 mm to 1.0 mm; and a distance separating each of the plurality of spaced-apart defect columns from an adjacent one of the plurality of spaced-apart defect columns on the cut edge of the first glass substrate and on the cut edge of the second glass substrate is within a range from 0.1 mm to 1.0 mm.

28. The structure of claim 24, wherein: the plurality of spaced-apart defect columns on the cut edge of one of the first glass substrate or the cut edge of the second glass substrate have a combined width; regions devoid of laser-induced defects are defined on the cut edge of the one of the first glass substrate or the cut edge of the second glass substrate, the regions devoid of laser-induced defects having a combined width along; and a ratio of the combined width of the regions devoid of laser-induced defects divided by the combined width of the plurality of spaced-apart defect columns is within a range from 5:1 to 1:5.

29. The structure of claim 24, wherein: each of the plurality of spaced-apart filamentation flaws on the cut edge of the first glass substrate and on the cut edge of the second glass substrate has a width within a range from 0.0005 mm to 0.0025 mm; and a distance separating each of the plurality of spaced-apart filamentation flaws on the cut edge of the first glass substrate and on the cut edge of the second glass substrate from an adjacent one of the plurality of spaced-apart filamentation flaws is within a range 0.001 mm to 0.01 mm.

30. The structure of claim 24, further comprising: a third substrate of transparent material that is generally parallel to the first glass substrate and the second glass substrate; and a spacer positioned between the first substrate of transparent material and the third substrate of transparent material to define a between-substrate space, the spacer sealing the between-substrate space from gas exchange with a surrounding environment and holding the first substrate of transparent material a separation distance from the third substrate of transparent material.

31. A method comprising: directing a laser beam into a mother sheet that comprises a first glass substrate joined to a second glass substrate with a plurality of defined zones each comprising an electrically controllable optically active material between the first glass substrate and the second glass substrate, wherein directing the laser beam into the mother sheet comprises forming a separation line to separate at least one of the plurality of defined zones from an adjacent region of the mother sheet, and wherein forming the separation line comprises forming a plurality of spaced-apart defect columns extending at least partially through the first glass substrate but not through the second glass substrate, each of the plurality of spaced-apart defect columns comprising a plurality of spaced-apart filamentation flaws; and separating one of the plurality of defined zones comprising the electrically controllable optically active material from the adjacent region of the mother sheet by at least separating a portion of the first glass substrate from the second glass substrate along the separation line to thereby configure the separated one of the plurality of defined zones with a shelf comprising by a portion of the second glass substrate extending outwardly from the separation line.

23; 23; 23; 23

edspap.20240198458