| 摘要 |
Below the phototransistors (O, N1 to N7 and V1 to V7), there are openings in a mask (M), of which the opening (U) allocated to a photo- transistor (O) exists several times and is visible and acts as raster. The V receivers of a first group (N1; N2; N3; V1; V2; V3) provide for leading scanning and the N receivers provide for lagging scanning. These receivers are all offset by +/- 1/4 pitch constant +/- 16 pitch intervals (line widths) of the zero track compared with the reading index I. The offset is an integral multiple of the pitch constant of tracks 1 to 3 and does not produce any change in the analysis result. A second receiver group comprises phototransistors (N4 to N7 and V4 to V7). The offset here comprises +/- 4 pitch intervals of the finest track. The detector arrangement maintains the minimum permissible receiver spacing in the entire receiver array, taking into consideration the dimensions of the individual receivers. The dimensions of the illuminated array with the detector arrangement are not exceeded. The tolerance in the position in the position of the receivers and the associated electronics can be matched to one another and is reduced overall. <IMAGE>
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