Thermometers can also be constructed from bimetallic strips . If the two strips are bonded together, the bimetallic strip will buckle or curl. Long bimetallic coils will uncoil slightly as the temperature rises if the inner strip has the larger a . If one end is fixed and a pointer is attached to the other end the pointer will move. The position of the pointer indicates the temperature.
Some liquid crystals change color when their temperature changes.
The selectively only reflect one color of the white light falling onto them. The color that is reflected back depends on the temperature and can be used as a temperature indicator.