IMAGE FORMING APPARATUS

PROBLEM TO BE SOLVED: To provide an image forming apparatus which can detect a surface condition of a fixing member with high accuracy regardless of the size or a flaw position of a recording medium to be used and which can maintain excellent image qualities.SOLUTION: The image forming apparatus comprises a photoreceptor drum 101, a charging unit 301, an exposure unit 200, a developing unit 102, a primary transfer unit 106, a photoreceptor cleaning unit 308, a fixing unit 111 having a fixing belt 67, a reflective optical sensor 68 which irradiates a surface of the fixing belt 67 with N pcs of light spots SP at an irradiation pitch P, a main body control unit 400 determining a surface condition of the fixing belt 67, moving means 70, and the like. The reflective optical sensor 68 is moved by the moving means 70 in such a manner that a passing position of a sheet end on the fixing belt 67 is disposed within an irradiation region P(N-1) of the light spot SP.