Optical measurement instrument

An optical measurement instrument comprising optical measurement elements and a base module, at least one of the optical measurement elements including an excitation light source arranged to produce an excitation beam for at least one of samples to be measured, and at least one of the optical measurement elements including a detector arranged to detect an emission beam emitted by one of the samples to be measured and to produce a detection signal responsive to the detected emission beam, and the base module comprising:

• a mechanical structure for forming a measurement chamber,
• a reception device inside the measurement chamber for receiving the samples to be measured,
• heating resistors placed at different places of the measurement chamber, each heating resistor being arranged to warm the measurement chamber,
• at least one temperature sensor, each temperature sensor being arranged to produce a temperature signal responsive to temperature of the measurement chamber, and
• a controller arranged to control electrical power supplied to each of the at least one heating resistor on the basis of the at least one temperature signal produced by the at least one temperature sensor,
• wherein at least one of the optical measurement elements is mounted to the mechanical structure forming the measurement chamber and the controller is arranged to control the electrical powers supplied to the heating resistors so that the electrical power supplied to a first one of the heating resistors is proportional to B1×q and the electrical power supplied to a second one of the heating resistors is proportional to B2×q, wherein q is a quantity controlled on the basis of one of the at least one temperature signal, B1 is a pre-determined balancing coefficient specific to the first one of the heating resistors, and B2 is a pre-determined balancing coefficient specific to the second one of the heating resistors, the balancing coefficient B1 having a different value than the balancing coefficient B2 in order to compensate effect of differences in temperature/power-characteristics related to surroundings of the first and second ones of the heating resistors.

A method for controlling temperature of samples being measured with an optical measurement instrument, the method comprising:

• producing, with at least one temperature sensor, a temperature signal responsive to temperature of a measurement chamber of the optical measurement instrument, the samples being located in the measurement chamber,
• controlling electrical powers supplied to heating resistors placed at different places of the measurement chamber on the basis of the temperature signal, and
• warming the measurement chamber with the heating resistors,
• wherein the electrical powers supplied to the heating resistors are controlled so that the electrical power supplied to a first one of the heating resistors is proportional to B1×q and the electrical power supplied to a second one of the heating resistors is proportional to B2×q, wherein q is a quantity controlled on the basis of one of the at least one temperature signal, B1 is a pre-determined balancing coefficient specific to the first one of the heating resistors, and B2 is a pre-determined balancing coefficient specific to the second one of the heating resistors, the balancing coefficient B1 having a different value than the balancing coefficient B2 in order to compensate effect of differences in temperature/power-characteristics related to surroundings of the first and second ones of the heating resistors.