| 摘要 |
<p>An optical measuring member for threads and wires comprises a light source (13) supplied by means of a square pulse voltage. The output value of a reference square section is maintained at a constant amplitude by means of an adjusting circuit. From the light source (13), there is formed a reference section and a measuring section, each lighting respectively an optoelectric transformer (17, 19). The output signals (I1, I2) of said transformers are connected in series. The difference (I2 - I1) between the signals of the measuring section and the reference section is provided through a high-pass filter to a multiplier (20), where the output signal is mixed with the pulse frequency and is applied to a low pass filter (21) wherefrom the measuring signal (Uo) may be outputted.</p> |
