concentric lens

例句：

1. 1.The lens of the telescope is made of a concentric ring of glass.
   望远镜的镜头是由一圈圈玻璃构成的同心环。
2. 2. The scientist used a concentric lens to focus the light on the sample.
   科学家使用一个同心透镜将光线聚焦在样品上。
3. 3. The camera lens is designed to be as close to the subject as possible without losing quality.
   相机镜头设计得尽可能靠近主体，以保持质量而不损失清晰度。