slant prism

例句：

1. 1.The scientist used a slant prism to observe the spectrum of light.
   科学家使用一个斜面棱镜来观察光的光谱。
2. 2. The slant prism helped the astronomer to identify the position of the planets.
   斜面棱镜帮助天文学家确定了行星的位置。
3. 3.The slant prism was used to create an illusion of depth in the painting.
   斜面棱镜被用来在这幅画中创造出深度的错觉。