| 摘要 |
PURPOSE:To prevent deterioration of the quality of a received picture due to deficient developer by providing a recording picture for measuring the density to the end of the surface of a photosensitive body and outputting a control signal when the recording density is lower than the reference value. CONSTITUTION:The 2nd latentimage is formed by exposing a prescribed luminous uantity intermittently to an end on the surface of a photosentivite body not transferred to the recording paper 11 at the outside of the radiation region of a scanning light radiated by 1st exposing device 3. A developer 5 develops the 1st 2nd latent images simultaneously to form 1st recording picture and 2nd recording picture. A sensor 7 radiates a prescribed quantity of light to the end of the photosensitive body 1 on which the 2nd recording picture is recorded, receives a reflected light from the 2nd recording picture and outputs a detected voltage 21 being the result of photoelectric conversion. A comparison section 8 outputs a control signal 22 when the detected voltage 21 is lower than the reference voltage representing the preset recording density by twice-ten times consecutively. An alarm section 9 receives a control signal 22 to apply the control such as lighting of alarm lamp, production of alarm tone and stop of reception. |
