Contact sensing device and the detection method, and the image reading apparatus to which is applied the contact sensing device

摘要

PPROBLEM TO BE SOLVED: To provide an image reading apparatus which can start (activate) the reading performance of a picture pattern appropriately according to the contact condition of a detected substance, by applying a contact detecting device and offering the contact detecting device which can detect the contact condition, and to provide its detection method when the detected substance laid and contacted on a detected surface on a photo sensor array. PSOLUTION: The image reading apparatus has a configuration having the 1st tactile electrode 10 and the 2nd tactile electrode 20 mutually separated, an opposing electrode 30 and a pulse generating circuit 40 which make the 1st tactile electrode 10 excite a signal voltage for a predetermined signal waveform, a limiting circuit 50 which restricts the voltage swing of the signal waveform excited to the 1st tactile electrode 10, and a detection circuit 60 which determines the contact condition of the detected substance OBJ to the 1st tactile electrode 10 and the 2nd tactile electrode 20 by detecting the change of a signal component represented to the 2nd tactile electrode 20. PCOPYRIGHT: (C)2004,JPO