Reflective display devices
View Patent ↗A technique of producing a control component for a reflective display device, comprising: forming an array of electronic switching devices; forming over said array of electronic switching devices an insulator region defining a controlled surface topography; and forming on the patterned surface of the insulator region by a conformal deposition technique a substantially planar array of reflective pixel conductors each independently controllable via a respective one of the array of electronic switching devices, wherein each pixel conductor exhibits specular reflection at a range of reflection angles relative to the plane of the array of pixel conductors for a given incident angle relative to the plane of the array of pixel conductors.
1. A method of producing a control component for a reflective display device, the method comprising:
forming over a substrate supporting an array of electronic switching devices an insulator region defining a surface having a controlled surface topography; and
forming on said surface of the insulator region by a conformal deposition technique a substantially planar array of reflective pixel conductors,
wherein each pixel conductor exhibits specular reflection at a range of reflection angles relative to the plane of the array of pixel conductors for a given incident angle relative to the plane of the array of pixel conductors,
wherein the controlled surface topography comprises an array of curved convex features and/or an array of curved concave features;
wherein forming said insulator region having said controlled surface topography comprises depositing insulating material over said substrate and patterning by laser ablating a surface of the insulating material to achieve said controlled surface topography, and
wherein said laser ablating comprises focusing a laser on a unit area of the surface of the insulating material via a succession of mask patterns, said mask patterns comprising dark field circles of different sizes; and
wherein said reflective pixel conductors are each independently controllable via a respective one of said array of electronic switching devices.
2. A method according to claim 1 , wherein the controlled surface topography is such that no point on said controlled surface topography has a tangent plane exhibiting an angle of more than about 10 degrees relative to the plane of the array of pixel conductors.
3. A method according to claim 1 , wherein the controlled surface topography exhibits a controlled degree of irregularity.
4. A method according to claim 1 , wherein the controlled surface topography defines a pattern repeated in an ordered manner over said surface of the insulator region.
5. A method according to claim 4 , wherein said repeating pattern exhibits a degree of irregularity.
6. A method according to claim 1 , wherein the controlled surface topography defines an irregular unit pattern repeated at a pitch substantially no smaller than the dimensions of one of the array of pixel conductors.
7. A method according to claim 1 , wherein the controlled surface topography defines an irregular unit pattern repeated at a pitch greater than the wavelength of visible light.
8. A method according to claim 1 , comprising focusing multiple laser shots on said unit area of said surface of the insulating material via said succession of different mask patterns.
9. A method according to claim 1 , wherein said mask patterns comprise respective portions of a single laser mask, and said patterning comprises changing the position of the laser mask relative to the unit area between laser shots.
10. A method according to claim 1 , wherein depositing said insulating material over said substrate comprises depositing said insulating material over said array of electronic switching devices.
11. A method according to claim 1 , wherein each of the curved convex and/or curved concave structures has a radius substantially larger than a total ablation depth.
12. A method according to claim 1 , wherein said controlled surface topography comprises curved convex structures having a radius substantially larger than a depth of ablation at a lateral edge of the curved convex structures.
13. A method of producing a control component for a reflective display device, the method comprising:
forming over a substrate supporting an array of electronic switching devices an insulator region defining a surface having a controlled surface topography; and
forming on said surface of the insulator region by a conformal deposition technique a substantially planar array of reflective pixel conductors,
wherein each pixel conductor exhibits specular reflection at a range of reflection angles relative to the plane of the array of pixel conductors for a given incident angle relative to the plane of the array of pixel conductors,
wherein the controlled surface topography comprises an array of curved convex features and/or an array of curved concave features;
wherein forming said insulator region having said controlled surface topography comprises depositing insulating material over said substrate and patterning by laser ablating a surface of the insulating material to achieve said controlled surface topography,
wherein said laser ablating comprises focusing a laser on a unit area of the surface of the insulating material via a succession of mask patterns,
wherein each of said mask patterns comprises dark-field parts, and wherein each mask pattern comprises a different amount of said dark-field parts to others of said mask patterns, and
wherein said reflective pixel conductors are each independently controllable via a respective one of said array of electronic switching devices.
14. A method comprising:
depositing insulating material over a substrate supporting an array of electronic switching devices;
laser ablating a surface of the insulating material after deposition over the substrate to define in said surface a controlled surface topography comprising an array of curved convex features and/or an array of curved concave features, wherein said laser ablating comprises focusing a laser on a unit area of a surface of the insulating material via a succession of different mask patterns, wherein each of said mask patterns comprises a dark-field circle, and wherein each mask pattern comprises a different size of dark-field circle with respect to others of said mask patterns;
forming on said surface of the insulating material having said controlled surface topography a substantially planar array of reflective pixel conductors by a conformal deposition technique;
wherein each pixel conductor exhibits specular reflection at a range of reflection angles relative to the plane of the array of pixel conductors for a given incident angle relative to the plane of the array of pixel conductors, and
wherein said reflective pixel conductors are each independently controllable via a respective one of said array of electronic switching devices.
15. The method according to claim 14 , wherein the controlled surface topography is such that no point on said controlled surface topography has a tangent plane exhibiting an angle of more than about 10 degrees relative to the plane of the array of pixel conductors.
16. The method according to claim 14 , wherein each of the curved convex and/or curved concave structures has a radius substantially larger than a total ablation depth.
17. The method according to claim 14 , wherein said controlled surface topography comprises curved convex structures having a radius substantially larger than a depth of ablation at a lateral edge of the curved convex structures.