Patent ID: 7574900

Claim:
A liquid state detection sensor for detecting the state of a liquid contained in a liquid container, comprising: a liquid condition detecting element that is to be placed in the liquid container and having a heating resistor which generates heat when a current is passed therethrough; an energizing unit for energizing the heating resistor for a prescribed detection period; a first corresponding value acquiring unit for acquiring, in the detection period, a first corresponding value which corresponds to a first resistance value of the heating resistor; a temperature information acquiring unit for determining a temperature of the liquid based on the first corresponding value; a second corresponding value acquiring unit for acquiring, after a lapse of the detection period, a second corresponding value which corresponds to a second resistance value of the heating resistor; a difference calculating unit for determining a difference between the second corresponding value and the first corresponding value; and a concentration acquiring unit for determining a concentration of a particular component of the liquid based on the difference between the second and first corresponding values, wherein the concentration acquiring unit determines the concentration of a particular component of the liquid based on the difference between the second and first corresponding values and the temperature of the liquid.