開かい口こう率りつ

noun

aperture ratio

Technical term used in optics, photography, and display engineering to describe the ratio of the effective opening area to the total area.

• このレンズの開かい口こう率りつはF2.8です。

  The aperture ratio of this lens is F2.8.

• 液えき晶しょうパネルの開かい口こう率りつが高たかいほど、画が面めんが明あかるくなります。

  The higher the aperture ratio of an LCD panel, the brighter the screen.