For grating in the optical pick-up head, the compensability between the longitudinal and transverse error practical references on the manufacture of grating.

对光学头分束光栅，其纵向差与横向差间存在补性，对光栅制作有着实际参考价值。

It is shown that test aerospike nozzle has good altitude compensability of thrust.

实验表明，塞式喷管有良好高度补偿能力和较高效率。