Self-dimming OLED lighting system and control method
View Patent ↗Lighting devices and operating methods are presented in which voltage or current perturbations of an OLED caused by a user pressing the OLED are monitored while the OLED is providing general lighting, and one or more lighting control signals are generated based on the sensed perturbations.
1. A lighting device, comprising:
a light panel comprising:
first and second light panel power connections for receiving DC electrical power from a driver, and
at least one organic light emitting diode (OLED) operatively coupled between the first and second light panel power connections to provide general lighting using current provided by the driver;
an actuation detect circuit operatively coupled with the light panel to sense a perturbation in a voltage across the first and second light panel power connections or in a current flowing through the at least one OLED caused by a physical actuation of the at least one OLED by a user while the at least one OLED is providing general lighting, and to selectively provide at least one actuation signal based at least partially on the sensed perturbation, the actuation detect circuit comprising:
an amplifier comprising an input and an output;
a capacitance coupled between one of the first and second light panel power connections and the input of the amplifier;
a comparator comprising:
a first comparator input coupled with the output of the amplifier,
a second comparator input coupled with a threshold voltage, and
a comparator output with an output voltage set according to relative polarities of voltages at the first and second comparator inputs;
a pulse detector operatively coupled with the comparator to detect the output voltage of the comparator output and to provide a pulse detector output based on the output voltage of the comparator output; and
a latch operative to latch the pulse detector output to provide the at least one actuation signal.
2. The lighting device of claim 1 , where the actuation detect circuit is operative to compare an amplitude of the sensed perturbation with a threshold, and to selectively provide the at least one actuation signal if the amplitude of the sensed perturbation is greater than the threshold.
3. The lighting device of claim 2 , where the actuation detect circuit is operative to compare the amplitude of the sensed perturbation with a plurality of thresholds, and to selectively provide the at least one actuation signal based at least partially on which of the plurality of thresholds are exceeded by the amplitude of the sensed perturbation.
4. The lighting device of claim 3 , where the actuation detect circuit selectively provides a plurality of actuation signals to indicate which of the plurality of thresholds are exceeded by the amplitude of the sensed perturbation.
5. The lighting device of claim 2 , where the actuation detect circuit comprises a processor operative to selectively provide at least one actuation signal or value if the amplitude of the sensed perturbation is greater than the threshold.
6. The lighting device of claim 5 , where the processor is operative to provide the at least one actuation signal or value only if a plurality of perturbations with amplitudes greater than the threshold are sensed within a non-zero predetermined time.
7. The lighting device of claim 1 , where the actuation detect circuit comprises a processor operative to selectively provide at least one actuation signal or value based at least partially on the sensed perturbation.
8. The lighting device of claim 7 , where the processor is operative to provide the at least one actuation signal or value only if a plurality of perturbations are sensed within a non-zero predetermined time.
9. The lighting device of claim 7 , where the processor is operative to selectively provide different actuation signals or values based at least partially on an amplitude of the sensed perturbation.
10. The lighting device of claim 7 , further comprising a communications interface operative to transmit messages to at least one external device, where the processor is operative to provide the at least one actuation signal or value to the communications interface for transmission to the at least one external device.
11. The lighting device of claim 1 , further comprising a driver operative to provide DC electrical power to the light panel via the first and second light panel power connections.
12. The lighting device of claim 11 , where the actuation detect circuit is operative to provide the at least one actuation signal to the driver, and where the driver is operative to selectively change an amount of DC electrical power provided to the light panel based at least partially on the at least one actuation signal.
13. The lighting device of claim 11 , further comprising a communications interface operative to transmit messages including at least one actuation signal or value to at least one external device based at least partially on the sensed perturbation.
14. The lighting device of claim 1 , further comprising a communications interface operative to transmit messages including at least one actuation signal or value to at least one external device based at least partially on the sensed perturbation.
15. An actuation detect circuit for detecting a physical actuation of one or more organic light emitting diodes (OLEDs) of a light panel providing general lighting, the actuation detect circuit comprising:
at least one light panel power connection for sensing a voltage or current associated with at least one OLED of a light panel;
a detect circuit operatively coupled with the at least one light panel power connection to sense a perturbation in a voltage across the at least one OLED or in a current flowing through the at least one OLED caused by a physical actuation of the at least one OLED by a user while the at least one OLED is providing general lighting, the detect circuit comprising:
an amplifier comprising an output and an input that is AC coupled with the at least one light panel power connection,
a comparator comprising:
a first comparator input coupled with the output of the amplifier,
a second comparator input coupled with a threshold voltage, and
a comparator output with an output voltage set according to relative polarities of voltages at the first and second comparator inputs,
a pulse detector operatively coupled with the comparator to detect the output voltage of the comparator output and to provide a pulse detector output based on the output voltage of the comparator output, and
a latch operative to latch the pulse detector output to provide the at least one actuation signal.
16. A power source for a lighting system, comprising
a driver circuit having first and second inputs for receiving input electrical power, and first and second driver outputs, the driver circuit operative to convert the input electrical power to provide DC electrical power via the first and second driver outputs to at least one organic light emitting diode (OLED) of a connected light panel to cause the at least one OLED to provide general lighting;
an actuation detect circuit operatively coupled with the connected light panel to sense a perturbation in a voltage across the first and second driver outputs or in a current flowing through at least a portion of the connected light panel caused by a physical actuation of the at least one OLED by a user while the driver circuit is providing DC electrical power to the at least one OLED, the actuation detect circuit operative to selectively provide at least one actuation signal based at least partially on the sensed perturbation, the actuation detect circuit comprising:
an amplifier comprising an input and an output:
a capacitance coupled between one of the first and second light panel power connections and the input of the amplifier;
a comparator comprising:
a first comparator input coupled with the output of the amplifier,
a second comparator input coupled with a threshold voltage, and
a comparator output with an output voltage set according to relative polarities of voltages at the first and second comparator inputs:
a pulse detector operatively coupled with the comparator to detect the output voltage of the comparator output and to provide a pulse detector output based on the output voltage of the comparator output; and
a latch operative to latch the pulse detector output to provide the at least one actuation signal.
17. The power source of claim 16 , wherein the actuation detect circuit provides the at least one actuation signal to the driver circuit, and where the driver circuit is operative to selectively adjust an amount of DC electrical power provided to the at least one OLED based at least partially on the at least one actuation signal.
18. The power source of claim 16 , further comprising a signal output, wherein the actuation detect circuit provides the at least one actuation signal to the signal output.
19. A method of controlling at least one lighting device, the method comprising:
providing DC electrical power to a light panel having at least one organic light emitting diode (OLED) to cause the at least one OLED to provide general lighting;
sensing a perturbation in a voltage across first and second power connections of the light panel or in a current flowing through the at least one OLED caused by physical actuation of the at least one OLED by a user while the at least one OLED is providing general lighting, comprising:
amplifying a capacitively coupled signal from at least one of the first and second power connections to provide an amplified output,
providing a comparison signal based on relative polarities of voltages of the amplified output and at least one threshold voltage,
providing a pulse signal based on the comparison signal, and
latching the pulse signal to provide at least one actuation signal; and
controlling at least one operational parameter of at least one device based at least partially on the at least one actuation signal.