Dual-band laser diode models

Dual-band laser diodes are available as monolithic or external-cavity systems, offering tunable or fixed dual-wavelength outputs with watt-level power for spectroscopy, LIDAR, and nonlinear optics applications.

Types of Dual-Band Laser Diodes

1. External-Cavity Dual-Wavelength Diodes These systems use a composite external cavity with elements like volume Bragg gratings (VBG) and Littrow-type transmission gratings to stabilize one wavelength while tuning the other. For example, a dual-wavelength diode can stabilize one line at 780.25 nm and tune the second line from 772.24–786.43 nm, achieving a total output power of 2.62–2.65 W with a side-mode suppression ratio exceeding 20 dB. These systems are suitable for nonlinear optical applications, such as four-wave mixing and alkali laser pumping . 2. DualDiode Modules Manufacturers like Omicron offer DualDiode modules where two laser diodes of equal wavelength are combined using co-linear optics. This configuration effectively doubles the output power while maintaining beam quality. These modules are temperature-stabilized and can be integrated with intelligent controllers for precise control of laser power, current, and temperature. They are widely used in printing, illumination, and quality control applications .

Key Specifications

• Wavelength Range: Dual-band diodes can cover visible to near-infrared ranges, e.g., 772–786 nm for tunable systems or fixed wavelengths like 405, 488, 532, 635 nm for commercial modules .
• Output Power: From a few watts in continuous-wave (CW) mode to tens of watts in pulsed mode. External-cavity systems can reach ~2.6 W, while DualDiode modules can achieve higher effective power by combining two emitters .
• Linewidth: Narrow linewidths (~0.13–0.17 nm) are achievable for high-resolution applications .
• Tuning and Stability: External-cavity designs allow continuous wavelength tuning and high side-mode suppression, while DualDiode modules provide temperature-stabilized fixed wavelengths.
• Beam Quality: Collimated fast and slow axes, often with cylindrical lenses or micro-optic correction for near-Gaussian profiles .
• Packaging: Options include TO-can, C-mount, fiber-pigtailed, or compact stand-alone modules with integrated controllers and thermoelectric cooling .

Applications

• Spectroscopy and Raman Sensing: Tunable dual-wavelength diodes enable selective excitation of molecular transitions.
• Nonlinear Optics: Four-wave mixing and blue light generation in alkali vapors.
• LIDAR and Distance Measurement: High-power pulsed dual-wavelength diodes improve range and resolution.
• Medical and Industrial: Fiber-coupled modules for laser pumping, skin treatment, or material processing.
• Redundancy and High-Speed Processing: DualDiode modules provide backup in case one emitter fails, maintaining continuous operation . Dual-band laser diodes offer a versatile solution for applications requiring high power, wavelength flexibility, and precise control, with options ranging from tunable external-cavity systems to robust dual-emitter modules for industrial and scientific use.