A semiconductor integrated circuit comprising: an acquisition unit configured to acquire an output value outputted from an infrared sensor in response to an infrared ray received from an object, and an output value outputted from a temperature sensor as a function of measured temperature of the infrared sensor; a storage unit configured to store correspondence among a first temperature which is a reference temperature, a temperature of the object at the time when the temperature of the infrared sensor is the first temperature, and the output value of the infrared sensor; and characterised by: a second-temperature identification circuit configured to identify a second temperature which is a temperature of the object at the time when the temperature of the infrared sensor corresponding to a measured value which is the output value of the infrared sensor, which is acquired by the acquisition unit, is the first temperature, by referring to the correspondence; a third-temperature identification circuit configured to identify a third temperature which is the temperature of the infrared sensor at the time when the infrared sensor outputs the measured value; and a calculation circuit configured to calculate a fourth temperature which is the a temperature of the object on the basis of the first temperature, the second temperature, and the third temperature. an acquisition unit configured to acquire an output value outputted from an infrared sensor in response to an infrared ray received from an object, and an output value outputted from a temperature sensor as a function of measured temperature of the infrared sensor; a storage unit configured to store correspondence among a first temperature which is a reference temperature, a temperature of the object at the time when the temperature of the infrared sensor is the first temperature, and the output value of the infrared sensor; and characterised by: a second-temperature identification circuit configured to identify a second temperature which is a temperature of the object at the time when the temperature of the infrared sensor corresponding to a measured value which is the output value of the infrared sensor, which is acquired by the acquisition unit, is the first temperature, by referring to the correspondence; a third-temperature identification circuit configured to identify a third temperature which is the temperature of the infrared sensor at the time when the infrared sensor outputs the measured value; and a calculation circuit configured to calculate a fourth temperature which is the a temperature of the object on the basis of the first temperature, the second temperature, and the third temperature. a second-temperature identification circuit configured to identify a second temperature which is a temperature of the object at the time when the temperature of the infrared sensor corresponding to a measured value which is the output value of the infrared sensor, which is acquired by the acquisition unit, is the first temperature, by referring to the correspondence; a third-temperature identification circuit configured to identify a third temperature which is the temperature of the infrared sensor at the time when the infrared sensor outputs the measured value; and a calculation circuit configured to calculate a fourth temperature which is the a temperature of the object on the basis of the first temperature, the second temperature, and the third temperature.