Color-filter device
A micro-transfer color-filter device comprises a color filter, an electrical conductor disposed in contact with the color filter, and at least a portion of a color-filter tether attached to the color filter or structures formed in contact with the color filter. In certain embodiments, a color filter is a variable color filter electrically controlled through one or more electrodes and can be responsive to heat, electrical current, or an electrical field to modify its optical properties, such as color, transparency, absorption, or reflection. In certain embodiments, A color-filter device includes connection posts and can be provided in or on a source wafer suitable for micro-transfer printing. In some embodiments, a color-filter device is disposed on a device substrate and can include a control circuit for controlling the color filter. An array of micro-transfer color-filter devices can be disposed on a display substrate in order to form a display.
1. A color-filter device, comprising:
a color filter;
an electrical conductor disposed in contact with the color filter; and
at least a portion of a fractured color-filter tether attached to the color filter or structures formed in contact with or supporting the color filter, wherein the color filter is a variable color filter.
2. The color-filter device of claim 1 , wherein the color filter is or comprises one or more of: a phase-change material, an electrically controlled ink, a gel, a photonic crystal, or a matrix of photonic crystals.
3. The color-filter device of claim 1 , wherein the color filter has a first side and a second side opposed to the first side, the electrical conductor is a first electrode disposed on the first side of the color filter, and the color-filter device comprises a second electrode disposed on the second side of the color filter,
wherein the color filter changes a color of light filtered by the color filter in response to (i) an electrical current, (ii) a voltage difference between the first and second electrodes, or (iii) an electrical field between the first and second electrodes.
4. The color-filter device of claim 1 , wherein the color filter is a stacked color filter.
5. The color-filter device of claim 1 , comprising two or more color filters each disposed in contact with at least one electrically separate electrical conductor, wherein the two or more color filters are disposed in a stacked configuration.
6. The color-filter device of claim 1 , wherein the color filter is a reflective color filter or a transmissive color filter.
7. The color-filter device of claim 1 , comprising a capacitor and a switch, the switch controllably connecting the capacitor to the electrical conductor.
8. The color-filter device of claim 7 , comprising a color-filter substrate on or over which the color filter and electrical conductor are disposed and wherein the switch and the capacitor form a control circuit that is disposed on or formed in the color-filter substrate and is located adjacent to or under the color filter.
9. The color-filter device of claim 1 , comprising a plurality of color filters, each color filter of the plurality of color filters having an electrically separate electrical conductor disposed in contact with said each color filter, wherein a color of light filtered by said each color filter of the plurality of color filters is a different color of light from a color of light filtered by other color filters of the plurality of color filters.
10. The color-filter device of claim 1 , comprising a color-filter substrate on, in, over, or under which the electrical conductor and the color filter are disposed.
11. The color-filter device of claim 10 , comprising an intermediate substrate comprising a fractured intermediate tether and wherein the color-filter substrate is disposed directly on the intermediate substrate or an adhesive layer formed on, over, or under the intermediate substrate.
12. A color-filter device wafer, comprising:
a wafer comprising a wafer substrate, the wafer substrate comprising a patterned sacrificial layer including sacrificial portions separated by anchors; and
a color-filter device disposed entirely over and in contact with each sacrificial portion, wherein the color-filter device comprises:
a color filter,
an electrical conductor disposed in contact with the color filter, and
at least a portion of a color-filter tether attached to the color filter or structures formed in contact with or supporting the color filter and physically connecting the color filter to an anchor,
wherein the color filter is a variable color filter.
13. The color-filter device wafer of claim 12 , comprising a plurality of variable color filters, each comprising at least a portion of a color-filter tether formed in contact with the color filter or structures formed in contact with or supporting the color filter and physically connecting the color filter to an anchor, disposed entirely over and in contact with a sacrificial portion of the patterned sacrificial layer, each color filter of the plurality of color filters having an electrically separate electrical conductor disposed in contact with the color filter, wherein a color of light filtered by each color filter of the plurality of color filters is a different color of light from a color of light filtered by other color filters of the plurality of color filters.
14. A color-filter device display, comprising:
a display substrate;
a plurality of color-filter devices disposed on the display substrate, wherein each color filter device comprises one or more variable color filters, each comprising at least a portion of a fractured color-filter tether, said each color filter of the one or more color filters having an electrically separate electrical conductor disposed in contact with the color filter, wherein a color of light filtered by said each color filter of the one or more color filters is a different color of light from a color of light filtered by other color filters of the one or more variable color filters of the plurality of color-filter devices.
15. The color-filter device display of claim 14 , comprising a plurality of color-filter substrates, each micro-transfer color-filter device disposed on a color-filter substrate.
16. A color-filter device, comprising:
a color filter;
an electrical conductor disposed in contact with the color filter; and
at least a portion of a color-filter tether attached to the color filter or structures formed in contact with or supporting the color filter, wherein the color filter is a variable color filter,
wherein the electrical conductor is a resistor that heats the color filter in response to an electrical current passed through the resistor and wherein the color filter changes a color of light filtered by the color filter in response to heat received from the electrical conductor.
17. The color-filter device of claim 16 , wherein the electrical conductor is substantially reflective.
18. A color-filter device, comprising:
a color filter;
an electrical conductor disposed in contact with the color filter;
at least a portion of a color-filter tether attached to the color filter or structures formed in contact with or supporting the color filter, wherein the color filter is a variable color filter;
a plurality of color filters, each color filter of the plurality of color filters having an electrically separate electrical conductor disposed in contact with the color filter, wherein the color of light filtered by each color filter of the plurality of color filters is a different color of light from the color of light filtered by other color filters of the plurality of color filters; and
a capacitor and a plurality of switches, each switch corresponding and electrically connected to the electrical conductor of said each color filter to controllably connect the capacitor to the electrical conductor.