camera tube with low velocity scanning beam

例句：

1. 1. The camera tube is the part of the camera that focuses light onto the film.
   相机管是相机中聚焦光线到胶片的部分。
2. 2. The engineer carefully inspected the camera tube to ensure it was functioning properly.
   工程师仔细检查了相机管，确保它正常工作。
3. 3. The camera tube is a critical component in the manufacturing process of cameras.
   相机管是相机生产过程中的关键部件。