(らがん)

らがん
noun
naked eye; unaided eye
1. naked eye; unaided eye; uncorrected vision
Seeing without glasses, contact lenses, or any optical aid. Used both in everyday contexts about vision correction and in scientific contexts about observation without instruments.
裸眼(らがん)では()えない。
It's not visible to the naked eye.
裸眼(らがん)視力(しりょく)左右(さゆう)とも0.3です。
My uncorrected vision is 0.3 in both eyes.
あの(ほし)裸眼(らがん)でも観察(かんさつ)できるほど(あか)るい。
That star is bright enough to observe with the naked eye.

Composed of () (naked, bare) + (がん) (eye). Literally means bare eyes — eyes without any optical aid.

COMMON COLLOCATIONS:

  • 裸眼(らがん)視力(しりょく) (uncorrected visual acuity)
  • 裸眼(らがん)()える (visible to the naked eye)
  • 裸眼(らがん)観察(かんさつ)する (to observe with the naked eye)
  • 裸眼(らがん)生活(せいかつ)する (to go about daily life without glasses)

SIMILAR WORDS:

  • 肉眼(にくがん) — naked eye; very similar but more commonly used in scientific contexts for observation without instruments
  • 矯正(きょうせい)視力(しりょく) — corrected vision (with glasses/contacts); the opposite measurement

USAGE:
At eye exams in Japan, 裸眼(らがん)視力(しりょく) (uncorrected vision) is measured first, followed by 矯正(きょうせい)視力(しりょく) (corrected vision). Japan uses a decimal scale (e.g., 1.0, 0.5) rather than the Snellen fraction used in English-speaking countries.