Apparatus for recording and reproducing charge latent image.

摘要

An apparatus for recording an image information on a recording medium comprises means for charging the recording medium (D) in response to a light from the object (Q); means for forming an effective region (TR1,TR2...) and a reference region (DP1,DP2...) on the recording medium, the effective region representing the image information, the reference region being charged to a reference potential; a sensing head (EDA) sequentially detecting surface potentials in the effective region and the reference region of the recording medium through electrostatic induction, the sensing head comprising field effect transistor means (DF1,DF2...); a gate input capacitance of the gate means of the transistor means being charged by a leakage current between the drain means and the gate means of the transistor means; means (ED1,ED2...,L1,L2...) for subjecting the gate means of the transistor means to a voltage electrostatically induced in correspondence with the surface potentials in the effective region and in the reference region of the recording medium; means (RF1,RF2...) for discharging a charge in the gate input capacitance; and means (20) for timely activating said discharging means with a predetermined timing relation to the detection of the surface potential of one of the effective region and the reference region of the recording medium by the sensing head.