iridial part of retina

例句：

1. 1.The study of the iridium in space has important implications for understanding the universe.
   研究空间中的铱对理解宇宙具有重要意义。
2. 2.The iridium crystals were used to create a unique color that was very popular in the 1960s.
   这些铱晶体被用来创造一种独特的颜色，在20世纪60年代非常流行。
3. 3. The iridium is found in small amounts in the earth's crust and mantle.
   铱在地球的地壳和地幔中以少量存在。