How Lasers Work (in practice) - Smarter Every Day 33 | Summary and Q&A

TL;DR

Learn the basic components and functioning of lasers from laser expert Johan Reinink in the Netherlands.

Key Insights

• 🫢 An open cavity laser consists of a laser tube, helium-neon gas, mirrors, and a slightly transparent mirror.
• 😁 Imperfections in the mirrors contribute to the output of the laser beam.
• ⚡ The intensity of the light is higher inside the laser cavity compared to outside.
• 😁 Blocking the laser beam inside the cavity prevents lasing.
• ⚾ Johan Reinink is a laser expert based in the Netherlands.
• 🙂 The laser tube amplifies the light passing through it.
• ❓ Laser limbo is a dangerous activity involving lasers.

Transcript

Hey it's me, Destin. Welcome to Smarter Every Day. So I'm in the Netherlands today and I'm hanging out with a buddy of mine that I met through a research project. His name is Johan Kr... - Reinink.

• That. So, anyway, Johan is a laser expert, and I've worked with him on stuff on the Internet. So we're going to show you how lasers work today. (Desti... Read More

Questions & Answers

Q: What are the main components of an open cavity laser?

An open cavity laser consists of a laser tube filled with helium-neon gas, mirrors at both ends to reflect the light back and forth, and a slightly transparent mirror that allows a small percentage of light to pass through.

Q: Why do the imperfections in the mirrors contribute to the laser output?

The imperfect mirrors allow a small portion of the light to leak out, resulting in the output of the laser beam. If the mirrors were perfect, no output would be observed.

Q: Why is the light intensity higher inside the laser cavity compared to outside?

The light circulating inside the laser cavity is amplified with each pass through the tube, resulting in a higher intensity. The leaked photons outside the cavity have lower intensity.

Q: What happens when a hand is placed inside the laser cavity?

Blocking the laser beam with a hand inside the cavity prevents the light from circulating and amplifying, resulting in the loss of lasing. No laser beam is produced on the other side of the tube.

Summary & Key Takeaways

• The main components of an open cavity laser include a laser tube filled with helium-neon gas, mirrors at each end to bounce the light back and forth, and a slightly transparent mirror that allows a small percentage of light to pass through.

• The imperfections in the mirrors are responsible for the output of the laser beam, as a perfect mirror would not produce any output.

• The light intensity inside the laser cavity is much higher than the leaked photons outside the cavity, and blocking the laser with a hand inside the cavity stops the circulation and prevents lasing.