The principle and property of synchronous focusing of a twin-laser in same light path and its realization technique are described. The design result is evaluated by use of a practical example.
叙述同一光路中双激光获得共焦的原理和特点及其实现技术，并就一实例的设计结果进行评价。
2
To reproduce the landscape in 3-D, a twin-engine plane flew over the city and fired laser beams through the dense tree canopy. The beams bounced off the ground, buildings, and other structures below.