| 摘要 |
PURPOSE:To convert image pickup image information having the uneven change of density into uniform information in a simple, quick and accurate way, by providing an optical filter to an image pickup means for working area to increase the degree of blur within a viewfield at the back of a self-traveling truck. CONSTITUTION:A filter 8 made of a transparent glass plate, etc., and containing mesh-shaped flaws which are coarser toward the upper side is provided at the front of a working or image pickup camera attached to a self-traveling truck in order to detect the boundary between a processed working area and an unprocessed working area. The image pickup viewfield range has the larger degrees of blur toward the back side of the truck. Thus the degrees of blur are not even. Therefore the uniform image pickup image information is obtained in a simple, quick and accurate way with no use of an electrical filter, etc. As a result, the local variation of brightness is not emphasized as a noise component in case the image pickup image information having an uneven range of density is uniformalized for detection of the boundary. |
