| 摘要 |
PROBLEM TO BE SOLVED: To always record an excellent image by deciding whether an electrostatic information recording medium is deteriorated or not, based on a voltage produced in a dark current measuring resistor. SOLUTION: A dark current measuring circuit 49 is provided with a power source 49a, a switch 49b, a dark current measuring resistor 49c and a voltage detecting part 49e. The dark current measuring resistor 49c is connected in series between the charge transfer layer 37b of the electrostatic information recording medium 31 and the negative polarity of the power source 49a. When the switch 49b is closed, the voltage is applied to the recording medium 31 and the resistor 49c by the power source 49a. At this time, the voltage produced in the resistor 49c is detected by the voltage detecting part 49e and a dark current flowing in the recording medium 31 is measured with the voltage, to obtain the resistance value of the medium 31. Then, it is decided whether the recording medium 31 is deteriorated or not, based on the voltage produced in the resistor 49c or the resistance value of the recording medium 31. |
