前まえ玉だま

noun

front lens element

Slang used among photographers and camera enthusiasts for the frontmost glass element of a camera lens assembly. Not a formal technical term.

• このレンズの前まえ玉だまに傷きずがついてしまった。

  The front element of this lens got scratched.

• 前まえ玉だまが大おおきいレンズは重おもくなりがちだ。

  Lenses with a large front element tend to be heavy.