bifocals

noun

1. 双光眼镜（上半為近視鏡片，下半為遠視鏡片）
   a pair of glasses with each lens made in two parts. The upper part is for looking at things at a distance, and the lower part is for looking at things that are close to you.

The form bifocal is used as a modifier. bifocal 用作修饰语。


1. N-PLURAL 双光眼镜；远近两用眼镜
   Bifocals are glasses with lenses made in two halves. The top part is for looking at things some distance away, and the bottom part is for reading and looking at things that are close.
   1. Mrs Bierce wears thick bifocal lenses.
      比耶尔斯太太戴着厚厚的双光眼镜。

1. Nowadays, these glasses are known as bifocals.
   如今，这些眼镜被称作双光眼镜。
2. Occasionally, children who have crossed eyes may need to have bifocals to help control the crossing.
   偶尔有内斜视的孩子会需要双光镜来控制内斜。
3. Calculation of minimum central thickness of fused-bifocals
   论熔合双光镜最小中心厚度的计算方法

noun

1. eyeglasses having two focal lengths, one for near vision and the other for far vision