Patent ID: 8718502

Claim:
A fixing device comprising: a fixing rotary body rotatable in a predetermined direction of rotation to radiate infrared rays; a pressing rotary body, rotatable in a direction counter to the direction of rotation of the fixing rotary body, pressed against the fixing rotary body to form a fixing nip therebetween through which a recording medium bearing a toner image is conveyed; a heater disposed opposite the fixing rotary body to heat the fixing rotary body; a temperature detector spaced apart from the fixing rotary body to detect a temperature of the fixing rotary body based on the infrared rays from the fixing rotary body and disposed below the fixing nip in a vertical direction; and a tube which penetrates through the heater and is disposed between the fixing rotary body and the temperature detector, the tube positioned such that the infrared rays from the fixing rotary body pass through the heater via the tube and then enter the temperature detector.