查询词典 focal axis

The rotary connection can be carried out in free space and hi-direction transmission of optical signal can be performed. Through analyzing the design principle of the optical structure and optical path calculation, it is found that when the ratio between the focal lengths for two lens is 20~50 and off-axis distance is in the range of 4~10mm, the interference will not be occurred between two optical channels and signal transmission can be lasted.

在自由空间可以实现旋转连接并实现光信号的双向传输，通过分析该光学结构设计原理和光路计算，发现每组透镜中两个透镜焦距之比为20-50，离轴距离为4-10mm范围时，才能保证光通道之间不发生干扰且信号持续传输。

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。