ILLUMINATION DEVICE CONTROL SYSTEMS AND METHODS

1 . A lighting system powerable by a primary power source, the lighting system comprising:

a lighting apparatus (i) comprising one or more light-emitting devices, and (ii) having a non-linear current-voltage relationship; and

a converter for operating the lighting apparatus via application of first and second voltages, the primary power source supplying power to the converter,

wherein the converter comprises:

a variable voltage source;

a sense element; and

a controller configured to:

(A) apply, via the variable voltage source, the first voltage to the lighting apparatus;

(B) measure, via the sense element, a first current resulting from the first voltage applied to the lighting apparatus;

(C) apply, via the variable voltage source, the second voltage to the lighting apparatus;

(D) measure, via the sense element, a second current resulting from the second voltage applied to the lighting apparatus, a current difference between the second current and the first current having a magnitude and a polarity;

(E) set the first voltage equal to the second voltage;

(F) alter the second voltage by a voltage increment based on the magnitude and the polarity of the current difference; and

(G) repeat steps (A)-(F) during operation of the circuit to regulate operation of the lighting apparatus notwithstanding any changes in the non-linear current-voltage relationship of the lighting apparatus during operation.

2 . The lighting system of claim 1 , wherein the primary power source supplies a constant-voltage output to the converter.

3 . The lighting system of claim 1 , wherein the primary power source supplies a constant-current output to the converter.

4 . The lighting system of claim 1 , wherein the converter is discrete and spaced apart from the primary power source.

5 . The lighting system of claim 1 , wherein an output of the converter is limited to a predetermined power value.

6 . The lighting system of claim 1 , wherein the controller is configured to alter the second voltage by:

if the magnitude of the current difference is greater than a pre-determined value and the polarity of the current difference is positive, increasing the second voltage by the voltage increment;

if the magnitude of the current difference is smaller than the pre-determined value and the polarity of the current difference is positive, decreasing the second voltage by the voltage increment;

if the magnitude of the current difference is greater than the pre-determined value and the polarity of the current difference is negative, increasing the second voltage by the voltage increment; and

if the magnitude of the current difference is smaller than the pre-determined value and the polarity of the current difference is negative, decreasing the second voltage by the voltage increment.

7 . The lighting system of claim 1 , wherein the non-linear current-voltage relationship of the lighting apparatus comprises a knee therewithin.

8 . The lighting system of claim 1 , wherein at least one light-emitting device comprises a plurality of light-emitting elements.

9 . The lighting system of claim 1 , wherein at least one light-emitting device comprises a plurality of light-emitting strings each comprising a plurality of series-connected light-emitting elements and at least one current-control element.

10 . The lighting system of claim 9 , wherein the at least one current-control element comprises two transistors and two resistors.

11 . The lighting system of claim 1 , wherein the sense element comprises a resistor.

12 . The lighting system of claim 1 , wherein the primary power source supplies power having a voltage or range of voltages different from a voltage or range of voltages usable by the lighting apparatus, the converter converting the supplied power into a form usable by the lighting apparatus.

13 - 46 . (canceled)