| 摘要 |
<p>1524376 Facsimile apparatus XEROX CORP 20 Oct 1975 [22 Jan 1975] 42984/75 Headings H4F and H3T In a facsimile scanner for resolving lines smaller than the aperture, the output of a photodetector 16 is preamplified and inverted at 15, the peak value of the inverted signal is detected at 25 and added to said inverted signal, whilst the inverted signal is also differentiated at 45 and rectified at 65 for comparison with the summed signal at 85. The comparison circuit produces an output when the differentiated signal is greater than the modulus of the summed signal and the width of the pulses so produced can be controlled by varying the level produced by the peak detector.</p> |
