JPS57186246A - Electrostatic recording system - Google Patents

Abstract

PURPOSE:To improve the S/N and reduce the cost of a recording circuit, by preventing always a recording head from contacting with a recording medium but contacting and separating the recording head with and from the recording medium in accordance with a binary signal and charging an electrostatic charge to the recording medium through the recording head only when the recording head is brought into contact with the recording medium. CONSTITUTION:When a binary signal voltage 21 indicated in figure (a) is applied across electrodes 7a and 7b from a recording circuit 10, a thickness (d) of a piezoelectric element 6 is changed. The piezoelectric element 6 is so set that the thickness (d) becomes small (large) to separate a recording head from a recording layer 2 (bring the recording head into contact with the recording layer 2) when the signal voltage 21 is in a low level L (in a high level H). Consequently, an electrostatic charge 22 is charged to the recording layer 2 as shown in figure (b), and the information signal is recorded in a form of presence and absence of the electrostatic charge 22. The noise charge due to friction is reduced to the half. Even if the noise charge is generated, it is generated only in the storage region of the electrostatic charge 22, and therefore, the S/N is improved considerably. Further, since the signal voltage 21 is permitted to be low, the recording circuit is realized easily and inexpensively.