| 摘要 |
<p>High-precision mercury thermometer comprises a glass capillary tube which is surface ground and polished in its longitudinal direction to a point close to the capillary passage, with a temp. scale marked on the cut face. Over the scale is mounted a profiled glass rod which magnifies the scale and the capillary passage. The profiled glass rod is pref. adhered to the cut face with a transparent adhesive having the same refractive index as glass, and pref. has a semicircular profile of which the circle dia. is greater than the width of the scale, or a prismatic profile which is wider at its base than the scale. The thermometer can easily be read with the naked eye without parallax, and mfd. at low cost. The profiled rod may instead be made of transparent plastic or plexiglass (RTM).</p> |
