The Remote Control Challenge: How Invisible Infrared Light Travels 15 Meters
I’m Ken Kuwako, your Science Trainer. Every day is an experiment.
“How far can a TV remote actually reach?”
Have you ever tried operating it from a distant corner of the room or intentionally testing its limits from far away? Well, I had the pleasure of lending a hand behind the scenes for a quiz that challenged exactly that limit. I served as the science supervisor for the program “Sokuketsu Nitaku Quiz!! Shirokuro” (Instant Two-Choice Quiz!! Black or White), which aired on Nippon TV on Sunday, October 26, 2025.
Can a Remote Control Work from 15 Meters Away?
The segment I supervised was the two-choice quiz: “Can a TV remote control turn on (or off) the TV from 15 meters away?” The experiment was performed live in the spacious environment of a TV studio, with the remote operator standing 15 meters away.
15 meters is nearly double the length of a standard school classroom (about 8 meters). You might think, “There’s no way it can reach that far…” But when the button was pressed…
…the TV miraculously turned off!
The Power of Invisible Light: Infrared Rays
How did the signal manage to travel that far? The secret lies in the light emitted by the remote, called “infrared rays.”
Infrared is a form of light invisible to our eyes, but it has the property of having a “longer wavelength” than the light we normally see (visible light).
For TV remotes, being invisible is an advantage because it’s not distracting. It’s also safer than ultraviolet rays because it carries less energy. More importantly, its long wavelength means it is less affected by obstacles like dust or water vapor in the air, giving it a strong “straight-line progression” (linearity), which allows it to travel far.
This is likely why the infrared signal from the remote was able to reach the TV receiver directly, even from 15 meters away. However, since infrared is a form of light, it will be blocked by solid obstacles such as walls or a person standing in the way. That’s why your remote sometimes stops working!
During the show, there was a narration and on-screen text explaining the “reason why infrared rays can travel so far.” My job was to check that the content was scientifically accurate and presented in a way that was easy for middle school students and the general public to understand. Though it was a small task, I was credited for the supervision.
Even the remote control you use every day is packed with fascinating scientific secrets. I encourage you all to look for the “whys” in the things around you!
Click here to learn how to see infrared rays with your own eyes:
Contact and Requests
Bring the wonder and fun of science closer to home! I’ve put together easy, fun science experiments you can do at home, along with simple explanations of the tricks behind them. Feel free to search around! ・The contents of my Science Notebook have been published in a book. Find details here ・About the founder and director, Ken Kuwako: here ・For various requests (writing, lectures, experiment classes, TV supervision, appearances, etc.): here ・Article updates are distributed on X!
My Science Tips Channel posts experiment videos!
４月のイチオシ実験！
- 光の魔法CMYウォーターキューブ：光の魔法を体験せよ！水を注ぐと新たな立方体が出現する魔法のような実験です。
テレビ番組・科学監修等のお知らせ
- 4月9日（木）「THE突破ファイル」（日本テレビ ）の科学監修を行いました。夜7時〜となります。
書籍のお知らせ
- サクセス15 ４月号にて、野球の科学について記事を執筆しました（2026/3）
- 『大人のための高校物理復習帳』（講談社）…一般向けに日常の物理について公式を元に紐解きました。特設サイトでは実験を多数紹介しています。※増刷がかかり６刷となりました（2026/02/01）
- 『きめる!共通テスト 物理基礎 改訂版』（学研）… 高校物理の参考書です。イラストを多くしてイメージが持てるように描きました。授業についていけない、物理が苦手、そんな生徒におすすめです。特設サイトはこちら。
講師・ショー・研究等のお知らせ
- 3/20（金） 日本理科教育学会オンライン全国大会2026「慣性の法則の概念形成を目指した探究的な学びの実践」について発表しました。
- 6/14（日） 千葉大学インスタレーション「探究」にて講師を務めます
- 7/18（土） 教員向け実験講習会「ナリカカサイエンスアカデミー」の講師をします。お会いしましょう。
- 10/10（土） 秘密兵器「帯電ガン」が炸裂！ビリビリ！ドキドキ！静電気サイエンスショー＠千葉市科学フェスタ（午後予定）
- 各種SNS X(Twitter)／instagram／Facebook／BlueSky／Threads
Explore
- 楽しい実験…お子さんと一緒に夢中になれるイチオシの科学実験を多数紹介しています。また、高校物理の理解を深めるための動画教材も用意しました。
- 理科の教材… 理科教師をバックアップ！授業の質を高め、準備を効率化するための選りすぐりの教材を紹介しています。
- Youtube…科学実験等の動画を配信しています。
- 科学ラジオ …科学トピックをほぼ毎日配信中！AI技術を駆使して作成した「耳で楽しむ科学」をお届けします。
- 講演 …全国各地で実験講習会・サイエンスショー等を行っています。
- About …「科学のネタ帳」のコンセプトや、運営者である桑子研のプロフィール・想いをまとめています。
- お問い合わせ …実験教室のご依頼、執筆・講演の相談、科学監修等はこちらのフォームからお寄せください。
- Frozen in Sight, Racing to Impact: The Terror of the Collision Course
- Spot the Invisible Force! 3 Rules of Equilibrium: Why the Action Line is Everything.
- The 0.001-Second Standoff: Unmasking the Mystery of Slow-Motion Electricity (Self-Induction Experiment)
- The Lunch Box Mystery: The Moment Scientific Laws Are Born.
- Turn Your Phone into Magic Eyes! The Mind-Blowing World of Visualizing Heat for $400 (FLIR ONE Pro)
- Shocking Truth: Can Humans Conduct Electricity? Let’s Try the Human Circuit Experiment! [Tamesu-kun]
- The Mystery of “Caloric”: From Middle School Myths to the Truth of Heat
- One LED, Seven Colors? Master the “Primary Colors of Light” with This Palm-Sized Experiment!
- Pinecone Magic! Craft an Eco-Friendly Christmas Tree & Discover Nature’s Secrets
