# [TECH] Laser (Device)

**The Laser** (Light Amplification by Stimulated Emission of Radiation) is a device producing coherent, monochromatic, collimated light, with applications spanning communications, manufacturing, medicine, and precision measurement.

## Overview

Theodore Maiman's first ruby laser (1960) was quickly followed by helium-neon (1960), semiconductor (1962), CO₂ (1964), and dye lasers. By the 1980s, semiconductor diode lasers enabled CD players, optical fiber communications, laser printers, and barcode scanners. High-power lasers cut and weld steel. Ultrashort pulse lasers (femtosecond) enable eye surgery (LASIK), multiphoton microscopy, and attosecond physics. Laser interferometry at LIGO detects gravitational waves.

## Key Actors

- **Companies**: Hughes Aircraft (first laser), Bell Labs, Coherent Inc. (1966), II-VI (now Coherent), IPG Photonics, JDSU, Lumentum
- **Inventors**: Theodore Maiman (1927–2007), Nick Holonyak Jr. (diode laser, 1962)

## Key Patents

- Schawlow, A. & Townes, C. US Patent 2,929,922 (1960) — laser (optical maser)
- Hall, R.N. US Patent 3,245,002 (1966) — semiconductor laser

## Economic Value

Global laser market: **\$19 billion/year** (2023, Strategies Unlimited). Industrial laser applications (cutting, welding): \$5B. Medical lasers: \$3B. Laser communications (optical fiber): enables \$30B+ infrastructure. Consumer (barcode, DVD, laser pointers): \$3B.

## Notes

Strategies Unlimited *Annual Laser Market Review* 2023. Optical fiber communications, enabled by semiconductor lasers, supports the internet — value \$11T+/year. Medical laser vision correction (LASIK) alone: 9M procedures/year, \$3B market.

## What This Enables
⏎
- **[TECH] Optical Fiber Communications** — Semiconductor laser diodes are the light sources in every optical fiber transmitter module.
- **[TECH] LIGO Gravitational Wave Detector** — LIGO's 4 km interferometers use a stabilised Nd:YAG laser at 1064 nm as their reference light source.
⏎
# Parents

* [SCI] Laser Physics & Stimulated Emission
* [SCI] Laser Physics & Stimulated Emission