The present invention provides an image capturing technique for obtaining, at the same time, multiple images with parallax and an image that would cause no sensitivity problem even without mechanically operating any part of its image capturing system. Object locations are determined based on signals generated from object identifiers attached to the tradeshow attendees and forwarded to an electronic device interfaced with a network. A dust seal fits in the annular groove of the stationary scroll. The content of the transmit buffers, is multiplexed and encoded by an inner decoder to improve protection by adding redundancy.