In 1920, the comparisoneyepiece is introduced, which allows simultaneous observation of two specimens under two microscopes.
1920年，比较目镜问世。此项技术使得可以同时观察到来自两台显微镜的样品。
2
In comparison with other sugar concentration detector with looking through eyepiece, the new detector has advantages of high stability and sensitivity, fast response and easy operation.