Disc light rotating instrument

The utility model provides a disc polarimeter, which belongs to the technical field of polarimeters, aims to solve the problem that the accuracy of experimental results is affected by inaccurate reading easily caused by dust shielding of an operator, and comprises a polarimeter base, a detection switch, a detection sodium lamp, a detection tube placement block, a detection dial, a detection eyepiece and a detection protection box, the detection switch is fixedly connected to the front end of the upper part of the polarimeter base; the detection sodium lamp is fixedly connected to the rear end of the upper part of the polarimeter base; the detection tube placing block is connected above the polarimeter base in a sliding manner; the detection dial is fixedly connected in front of the detection tube placement block; the detection eyepiece is fixedly connected in front of the detection dial; and the detection protection box is fixedly connected to the middle position of the detection eyepiece, so that the height