bifocal
adj. (指眼鏡片)雙焦的,雙光的,有二重觀點的
n. 雙重焦點透鏡,雙光眼鏡
1. having two foci;
Use bifocal or varifocal lenses may relieve asthenopia.
如改用雙焦點或漸進多焦點鏡片可能有助於減輕視疲勞.
bifocals