1. Overview

Laser diodes (LDs) are semiconductor devices that emit coherent light through stimulated emission. Laser modules integrate LDs with optical components, drivers, and thermal management systems. These devices are critical in telecommunications, medical systems, industrial processing, and consumer electronics due to their high efficiency, compact size, and precise beam control.

2. Main Types and Functional Classification

3. Structure and Components

Laser Diodes: Composed of an active region (quantum well structure), cladding layers, and a resonant cavity formed by cleaved facets. Electrical contacts enable current injection.

Laser Modules: Integrate LDs with:

• Collimating optics and beam-shaping elements
• Photodiode feedback for power stabilization
• Thermoelectric coolers (TEC) for temperature control
• Driver circuits with modulation capabilities

4. Key Technical Specifications

5. Application Fields

Telecommunications: DWDM systems, free-space optical links

Medical: Laser scalpels, photodynamic therapy devices

Industrial: Cutting/welding machines, 3D printers

Consumer Electronics: LiDAR for AR/VR, facial recognition systems

Scientific: Atomic clocks, quantum computing research

6. Leading Manufacturers & Products

7. Selection Guidelines

Key considerations:

• Wavelength compatibility with target material/transmission medium
• Required power stability over temperature variations
• Modulation speed requirements for communication systems
• Environmental factors (humidity, vibration, operating temperature)
• Form factor constraints and cooling method availability

8. Industry Trends

Emerging developments include:

• High-power single-mode fiber lasers for metal processing
• VCSEL arrays with >50% wall-plug efficiency for LiDAR
• Photonic integrated circuits combining LDs with modulators
• UV and deep-IR emitting devices for advanced spectroscopy
• AI-driven thermal management systems for extended lifetime