Lithographic apparatus and to a reflector apparatus

A method of controlling the temperature of a reflector, the method comprising:

• supplying power to an array of thermoelectric heat pumps, wherein each thermoelectric heat pump is electrically insulated from another and comprises a first and a second semiconductor block and an electrical insulation layer disposed between the first and second semiconductor blocks, the power supplied to the array of thermoelectric heat pumps causing the thermoelectric heat pumps to remove heat from or transfer heat to the reflector;
• independently controlling each thermoelectric heat pump of the array of thermoelectric heat pumps;
• and
• determining a temperature of the reflector from a voltage measured across at least one of the thermoelectric heat pumps.

A support for supporting an object, the support comprising;

• a support surface configured to receive the object, the support further comprising:
• an array of thermoelectric heat pumps, wherein each thermoelectric heat pump is electrically insulated from another and comprises a first and a second semiconductor block and an electrical insulation layer disposed between the first and second semiconductor blocks;
• and
• a controller configured to independently control each thermoelectric heat pump of the array of thermoelectric heat pumps, whereby the controller is configured to, in use, determine a temperature of the object from a voltage measured across at least one of the thermoelectric heat pumps.