How Lasers Work (in practice) - Smarter Every Day 33

TL;DR

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

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

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.

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.