| 摘要 |
<p>The cassette to be used in an apparatus having a screen for showing a plurality of different pictures sequentially comprises two sets of sheets, each being divided in strips (1a, 1b, 1c resp. 2a, 2b, 2c). The strips are made by cutting lines which at their ends are joining openings. The openings in the sheets of the foremost set extend upwards from the cutting line, and the openings in the sheets of the rearmost set extend downwards from the cutting line. Thus the sheets and hence the strips are mutually displaceable in a vertical direction, and the picture segments on the strips (2b) in a sheet belonging to the rearmost set can be displaced upwardly beyond the upper edges of the strips (1a) in a blank front sheet (1). Corresponding picture segments on the strips in a sheet belonging to the foremost set can be displaced further upwards to cover the remaining segment of the strips in the front sheet (1a), whereby a complete picture becomes visible. The vertical movements of the sheets can be controlled by motor-driven guide means acting on the marginal portions of the sheets. For each picture to be shown, the cassette has to contain only two sheets carrying identical pictures, i.e. a picture sheet in the foremost set and a picture sheet in the rearmost set.</p> |
