| 摘要 |
PURPOSE:To make it possible to detect only the linear pattern in the direction coinciding with the running direction of a recording body, by performing reading scanning to the direction crossing the running direction of the recording body at right angles and providing integrating action to the optical system arranged in the side of the recording body. CONSTITUTION:When a non-accumulation type unidimensional image pick-up element is arranged to a real image forming plane so as to make a reading scanning direction vertical to the plane formed by a tape running direction and an optical axis, a wide range of a pattern in the tape running direction is formed to a narrow range (that is, the integration of quantity of light is performed) and, therefore, the width of an image due to damage A crossing the tape running direction at right angles can be made extremely fine. Further, the image of the damage B toward the tape running direction is formed on the image pick-up element without contracting the width of said damage B. Therefore, because the width itself of the damage does not become fine with respect to the damage B in the tape running direction, even if said damage B is picked up by using the unidimensional image pick-up element having no accumulating action, the image pick-up output of the damage A is reduced to a large extent and only the damage B in the direction coinciding with the tape running direction can be detected.
|
