| 摘要 |
<p>An amplifying circuit for amplifying an output from a measurement wavelength detector consists of a preamplifier and a measurement signal amplifier provided at an output of said preamplifier. The measurement signal amplifier is provided with an input-resistance and a feed-back resistance, a variable resistance connected in series to a normally open switch, the series combination being connected in parallel to the feed-back resistance so that the gain of the measurement signal amplifier may be variable.</p> |
