Patent ID: 7881625

Claim:
A fixing device comprising: a heating target member that includes a heat roller and a press roller, and comes in contact with a fixing target medium and fixes a toner image on the fixing target medium; a first heater configured to heat a center part of the heat roller; a second heater configured to heat a side part of the heat roller; a non-contact temperature sensor member to detect temperatures of a plurality of positions which includes a non-imaged formation area of the heat roller; a contact temperature sensor member that is positioned on the non-image formation area, comes in contact with a same phase position as a temperature detect position by the non-contact temperature sensor member and detects a temperature of the heat roller; and a first comparison unit that compares a detection result of the non-imaged formation area which is measured by the contact temperature sensor member and a detection result of the non-imaged formation area which is measured by the non-contact temperature sensor member.