light-spot galvanometer

例句：

1. 1. The light-spot galvanometer was used to measure the brightness of the sun.
   光点计被用来测量太阳的亮度。
2. 2. The light-spot galvanometer was used to detect the presence of a particular chemical in the sample.
   光点计被用来检测样本中特定化学物质的存在。
3. 3. The light-spot galvanometer was used to measure the intensity of the light source.
   光点计被用来测量光源的强度。