Patent ID: 7558499

Claim:
A fixing apparatus, comprising: a heating member which is a cylindrical member having a center axis, the heating member having an outer peripheral surface which is heated; a temperature detecting member placed in an area located vertically below the center axis of the heating member and vertically below the outer peripheral surface of the heating member, the temperature detecting member including a detection surface which receives infrared radiation from the heating member and a lens which condenses the infrared radiation from the heating member on the detection surface, the temperature detecting member detecting the temperature of the outer peripheral surface of the heating member on the basis of the received infrared radiation; and a heating device which heats the heating member to a target temperature on the basis of the temperature detected by the temperature detecting member, wherein an optical axis of the lens is inclined at a predetermined angle to the outer peripheral surface of the heating member including a point where the optical axis of the lens crosses a surface of the heating member.