Alternating current light emitting device
View Patent ↗A light emitting device and the fabrication method includes forming one or more light emitting modules on a substrate. The light emitting module receives an alternating current input and has at least two micro diodes. Each micro diode has at least two active layers and is electrically connected by a conductive structure so as to allow the active layers of the micro diodes to alternately emit light during positive and negative cycles of the alternating-current input.
1. A light emitting device, comprising:
a substrate;
a light emitting module configured to receive an alternating-current input, the light emitting module being formed on the substrate and having at least two micro diodes, each micro diode having a lower active layer and an upper active layer formed over the lower active layer, the lower active layer being larger than the upper active layer; and
a conductive structure formed over the substrate and the lower active layers of the at least two micro diodes, between the at least two micro diodes, and electrically connected to the at least two micro diodes so as to allow the lower and upper active layers of each of the at least two micro diodes to alternately emit light during positive and negative cycles of the alternating-current input.
2. The light emitting device of claim 1 , wherein the substrate comprises a chip.
3. The light emitting device of claim 1 , wherein the substrate comprises an insulating substrate.
4. The light emitting device of claim 1 , wherein each of the lower and upper active layers comprises a luminescent active layer.
5. The light emitting device of claim 1 , wherein the conductive structure comprises a conductor electrically connecting the at least two micro diodes.
6. The light emitting device of claim 1 , wherein the conductive structure is formed as a conductive bridge electrically connecting the at least two micro diodes.
7. The light emitting device of claim 1 , wherein the at least two micro diodes or the lower and upper active layers of the micro diodes emit light at identical or different wavelengths.
8. The light emitting device of claim 1 , wherein the lower and upper active layers of the at least two micro diodes have individual ohmic electrodes.
9. The light emitting device of claim 1 , wherein the upper active layers of one micro diode and its adjacent micro diode alternately emit light during the positive and negative half cycles of the alternating-current input, and the lower active layers of one micro diode and its adjacent micro diode alternately emit light during the negative and positive half cycles of the alternatinq-current input.
10. The light emitting device of claim 1 , wherein the upper active layer of one micro diode and the lower active layer of its adjacent micro diode alternately emit light during the positive and negative half cycles of the alternating-current input.
11. The light emitting device of claim 1 , wherein the at least two micro diodes are fabricated by one of a flip-chip, wafer bonding or an epitaxy technique.
12. The light emitting device of claim 1 , further comprising a connection layer between the lower and upper active layers.