3

Should it be read 「じゅ」 or 「う」 or something else?

1
9

受{う} isn't really a thing in Modern Japanese―that's just part of 受{う}ける or 受{う}かる. Most of the time, if the word is 受ける or 受かる, you can tell how to read the kanji because of the okurigana. And when there are no okurigana, it's usually じゅ instead.

There are a few deverbal examples where the okurigana may not be used, such as 受付{うけつけ} or 受身{うけみ}. With this sort of word, the okurigana aren't really needed because the word is no longer a verb, and therefore it doesn't inflect (change form). And if it doesn't change form, the okurigana aren't needed to indicate the part of the word that changes.

Sometimes when compound verbs are built on 受{う}け, people choose not to write the け, although it's still pronounced. They may write 受入れる instead of 受け入れる, or 受渡す instead of 受け渡す, or 受取る instead of 受け取る. Although this is somewhat less common, the reason is the same as in the deverbal examples above; since 受け doesn't change form in these compounds, the okurigana aren't really needed.

But those are more or less exceptions. In most cases, if you see 受 in a big string of kanji with no okurigana, unless you recognize it as part of a word like 受付 or 受身, you'll be using Sino-Japanese readings (音読み). The Sino-Japanese reading for 受 is じゅ, and that's the right reading in this case.

For more discussion about the word 受 appears in, please see naruto's answer.

6

I think it's read せきがいせんじゅはっこうぶ.

受発光 should be from 受光【じゅこう】 (light receiving) and 発光【はっこう】 (light emission), so 赤外線受発光部 is a part which both emits and receives infrared light.

It's similar to 送受信【そうじゅしん】 (two-way transmission, sending and receiving), which is from 送信【そうしん】 and 受信【じゅしん】.

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.