Visible Lasers

The term visible lasers is used to denote lasers emitting visible light, or sometimes laser devices generating visible light via nonlinear frequency conversion. Visible light (for human eyes) corresponds to optical wavelengths roughly between 400 nm and 700 nm.

Lasers with Direct Visible Emission

Lasers which directly emit visible light constitute a minority — most lasers emit in the infrared spectral region. Some examples of solid-state lasers emitting visible light are:

• Various laser diodes can emit visible light. Examples are GaInP and AlGaInP-based red laser diodes, and GaN-based blue-emitting diodes.
• The first demonstrated laser was a ruby laser emitting at 694.3 nm.
• titanium–sapphire lasers emit mostly in the infrared spectral region, but can be tuned down to roughly 650 nm.
• There are various upconversion lasers, including both bulk and fiber lasers, with visible light emission.

There are also various gas lasers emitting visible light:

• The helium–neon laser was the first gas laser with visible emission. It can emit on various visible wavelengths, including the well-known 632.8 nm red wavelength but also in the green (543.5 nm), yellow (594.1 nm) and orange (604.6, 611.9 nm) spectral region.
• helium–cadmium lasers (→ metal vapor lasers) emit in the blue at 441.6 nm.
• Argon ion lasers emit mostly at 514.5 and 488 nm, but also at 465.8, 472.7 and 528.7 nm.
• Krypton ion lasers emit at various wavelengths throughout the visible spectrum, in particular at 647.1 nm and 530.9 nm.
• Copper vapor lasers (→ metal vapor lasers) emit at 510.6 nm (green) or 578.2 nm (yellow).

Finally, various dye lasers have broad emission ranges throughout the visible spectral region.

See also the articles on red, green and blue lasers.

Visible Laser Systems Based on Nonlinear Frequency Conversion

Various methods allow the generation of visible light in laser diodes via nonlinear frequency conversion:

• The most frequently used approach particularly for green and blue emission is frequency doubling, either intracavity or in an external nonlinear crystal (single-pass or resonant). This can be applied to traditional solid-state bulk lasers and also to VECSELs. Most common are green-emitting laser sources based on frequency-doubled 1064-nm neodymium lasers.
• Sum frequency generation in a nonlinear crystal can generate visible light. For example, sum frequency mixing of a 1064-nm Nd:YAG laser and a 1.5-μm fiber laser leads to red light.
• A Raman laser can be pumped with light from a regular laser. This is most often done with solid-state bulk lasers, which may be Q-switched or continuous-wave, and often intracavity frequency doubled.
• For broadband visible radiation, there are laser sources involving supercontinuum generation.

Applications of Visible Lasers

Some examples of applications of visible lasers:

• Laser pointers and various alignment lasers should emit in the visible range, as otherwise it would be more difficult to track the beam.
• Laser scanners, LIDAR and interferometry are partially done with visible lasers. For holography, it is also common.
• There are laser-based displays, e.g. based on RGB sources.
• In some applications, one requires short wavelengths (shorter than for infrared light) to excite fluorescence of some substances. Examples are fluorescence microscopy and flow cytometry.
• Short wavelengths also greatly increase the amount of light scattering, which can be useful, for example, in laser Doppler velocimetry and other types of sensors, e.g. in optical computer mice.
• Laser surgery partially uses visible lasers. Photodynamic therapy is another example in the medical area.
• In applications like optical data storage, the shorter wavelengths of visible light are beneficial for focusing to small points and thus reaching a high data density.

Frequently Asked Questions

Suppliers

Sponsored content: The RP Photonics Buyer's Guide contains 178 suppliers for visible lasers. Among them:

⚙ hardware

TOPTICA’s visible lasers deliver exceptional performance for applications in biophotonics, spectroscopy, fluorescence measurements, and a wealth of quantum technologies. Covering the entire visible wavelength range (and beyond), these lasers combine mode-hop-free tuning, narrow linewidths, low intensity noise, and convenient software control. TOPTICA’s visible lasers categories include the following:

• tunable diode lasers
• single-mode diode lasers
• fiber-amplified lasers
• multi-laser engines

All are designed to deliver outstanding performance and stability across the visible wavelength range.

⚙ hardware

MPBC’s visible fiber laser line originated in 2004 with the development of a 200 mW 560 nm laser for Harvard University Department of Chemistry. Since then, MPBC has expanded its portfolio to include continuous-wave, single-frequency, pulsed, and ultrafast visible fiber lasers for industrial, medical, military, space, and scientific applications.

Our visible fiber lasers are built on an all-fiber architecture, ensuring diffraction-limited, linearly polarized output with outstanding wavelength stability, excellent beam quality (M² < 1.1), and high reliability across all models.

Our products include:

• Continuous-wave (CW) visible fiber lasers covering 465–775 nm, providing up to 5 W of output power at selected wavelengths.
• Single-frequency fiber lasers covering the 460–760 nm range, offering up to 5 W of output power optimized for quantum technology applications. For higher power requirements, MPBC’s technology can be scaled up to 100 W, enabling advanced applications such as Laser Guide Star (LGS) systems for adaptive optics in astronomical telescopes.
• Pulsed visible & NIR fiber lasers spanning 514–1700 nm, delivering up to 20 W of output power, depending on wavelength and repetition rate.
• Dual pulsed visible fiber laser integrating two sources — 589 nm and 655 nm — in a single package, offering up to 2 W of average power for each source.
• Visible ultrafast picosecond mode-locked fiber laser operating from 514–595 nm, with fixed repetition rates from 30–100 MHz.

These systems offer long operational lifetimes, low power consumption, and minimal maintenance requirements, while eliminating common free-space laser challenges such as optical cleaning and cavity misalignment caused by temperature fluctuations or vibration.

Questions and Comments from Users