Seeing and insight with

refers to the “eye” itself, which governs vision, as well as the “gaze” that sees through to the essence of things.

Etymology

This kanji is a phono-semantic compound comprised of 目 (eye) as the semantic component and 艮 (stopping) as the phonetic component, giving the on-reading ガン. These invoke imagery of an eye fixed on something before it, holding it clearly in view.

Sight and View

(Naked eye)

肉眼(にくがん) refers to seeing things with your own eyes, without using optical instruments such as telescopes, microscopes, or magnifying glasses.

It combines 肉 (flesh) with 眼 (eye) to show the natural bodily eye.

Manga panel from 怪盗セイント・テール showing example of Seeing a comet with the naked eye with 肉眼.
怪盗セイント・テール » Volume 4 » Page 6

Before class, Asuka Jr. mentions a Graham Comet, which passes near the Earth once every fifty years.

涼子(りょうこ):
「ステキ!! それが こんどのクリスマス・イヴにくるの?」
“Awesome!! Is it coming this Christmas Eve?”
アスカ Jr.:
「どーせ肉眼(にくがん)じゃ()えねーよ。天文台(てんもんだい)にでもいかないとな」
“You won't be able to see it with the naked eye anyway. You'd have to go to an observatory or something.”
View Full Example

(Unaided vision)

裸眼(らがん) refers to the state of seeing things with one’s natural eyes, without the use of corrective devices such as glasses or contact lenses.

It combines 裸 (bare) with 眼 (eye) to show the eye in its uncovered, unaided state.

Manga panel from 僕が僕であるために。 showing example of Poor vision without glasses with 裸眼.
僕が僕であるために。 » Volume 2 » Page 50

Shun asks Ayumu to continue switching places with him, since pretending to be Ayumu helps him be more open. Ayumu is game, but this requires Shun to go without his glasses, so Ayumu suggests he get contact lenses. Shun asks, “Contacts?”

(あゆむ):
「そう!()(わる)いんでしょ?」
“That's right! You have bad eyesight, don't you?”
駿(しゅん):
「0.6くらいだから裸眼(らがん)だときりぎり生活(せいかつ)できるくらいかな…」
“My vision's about 0.6, so without glasses, I can just barely get by in daily life...”
View Full Example

(Binoculars)

双眼鏡(そうがんきょう) is an optical device consisting of two telescopes placed side by side, allowing the user to view distant scenery or objects through both eyes simultaneously.

It combines 双 (pair), 眼 (eyes), and (lenses) to show a paired viewing tool for both eyes.

Manga panel from 名探偵コナン showing example of A pair of binoculars among other items with 双眼鏡.
名探偵コナン » Volume 4 » Page 117

Ayumi leaves the bag with her new Masked Yaiba doll outside while she’s in the restroom. When she returns, she finds the bag waiting for her, but the doll is gone. Ran suggests someone may have taken her bag by mistake. Genta decides to see what’s in the bag Ayumi brought back, dumping its contents onto the ground.

元太(げんた):
「えーっと… 地図帳(ちずちょう)双眼鏡(そうがんきょう)に…」
“Um... an atlas, binoculars...”
懐中電灯(かいちゅうでんとう)…」
“...a flashlight...”
View Full Example

Vision Tools and Protection

(Glasses)

眼鏡(めがね) refers to devices worn in front of the eyes to correct vision, protect the eyes, or serve as an accessory.

It combines 眼 (eye) with (lens) to show lenses worn before the eyes for seeing.

Manga panel from 名探偵コナン showing example of Broken glasses with 眼鏡.
名探偵コナン » Volume 21 » Page 28

Professor Agasa and the Detective Boys stay overnight in a large villa in the woods after getting lost on a camping trip. Conan and Agasa go missing, leaving the rest of the kids to sneak around at night to search the property for them. After entering a secret passage, Haibana finds spots of blood on the ground, and then Genta finds Agasa’s glasses.

元太(げんた):
「な、なんで博士(はかせ)眼鏡(めがね)がこんな(ところ)()ちてんだ!?」
“W-what the heck? Why are the professor's glasses lying here!?”
歩美(あゆみ):
()れてるし()もついてる…」
“They're broken and there's blood on them...”
View Full Example