Described is dynamic control of the temperature of the envelope of an HID lamp in order to stabilize the output color temperature of the lamp. As the lamp power is changed, or environmental factors alter the lamp envelope temperature, the system senses these changes and adjusts the lamp cooling systems so as to move the lamp envelope temperature back to the desired point.

The invention describes an ignitor arrangement (1) for a high-intensity discharge lamp (2), which ignitor arrangement (1) comprises a first pair of input terminals (101, 102) for applying an ignition voltage to the ignitor arrangement (1); a second pair of input terminals (101, 103) for applying an input drive voltage to the ignitor arrangement (1); and a discharge resistor (10) arranged in the interior (100) of the ignitor arrangement (1) and connected across the first input terminal pair (101, 102), which discharge resistor (10) is realized as a temperature-dependent resistor (10). The invention also describes a lamp driver (3) realized to drive a high-intensity discharge lamp (2); a lighting arrangement (4); and a method of driving a high-intensity discharge lamp (2).

Described is dynamic control of the temperature of the envelope of an HID lamp in order to stabilize the output color temperature of the lamp. As the lamp power is changed, or environmental factors alter the lamp envelope temperature, the system senses these changes and adjusts the lamp cooling systems so as to move the lamp envelope temperature back to the desired point.

A discharge switch device is provided that includes a comparator portion, a temperature compensation diode, and a trigger portion. The comparator portion is configured to compare an input voltage value to a reference voltage value. The temperature compensation diode is configured to reduce variation of the reference voltage value. The trigger portion is configured to discharge stored energy when the input voltage value exceeds the reference voltage value.

The invention describes an ignitor arrangement (1) for a high-intensity discharge lamp (2), which ignitor arrangement (1) comprises a first pair of input terminals (101, 102) for applying an ignition voltage to the ignitor arrangement (1); a second pair of input terminals (101, 103) for applying an input drive voltage to the ignitor arrangement (1); and a discharge resistor (10) arranged in the interior (100) of the ignitor arrangement (1) and connected across the first input terminal pair (101, 102), which discharge resistor (10) is realised as a temperature-dependent resistor (10). The invention also describes a lamp driver (3) realised to drive a high-intensity discharge lamp (2); a lighting arrangement (4); and a method of driving a high-intensity discharge lamp (2).