Several full-spectrum imaging techniques have been introduced in recent years that promise to provide rapid and comprehensive chemical characterization of complex samples. It is another object of the invention to provide a light emitting element, which is resistant to repetition of a reduction reaction. A voltage source is adapted to apply a voltage to the thermoelectric modules to cause a temperature change in each thermoelectric module so as to control the temperature of the object in accordance with the pattern and with the voltage applied to thermoelectric modules. The hand wheel is connected to the first shaft such that the hand wheel and the first shaft drive one another.