Diode laser systems emitting in the blue and UV spectral range

Diode laser based light sources with an emission in the blue spectral range are developed for generating UV laser emission by nonlinear frequency conversion. Potential applications are Raman spectroscopy, utilizing the spectral separation of Raman signals from disturbing contributions such as fluorescence at longer wavelengths, and absorption spectroscopy.

Working principle

Commercially available GaN based diode lasers at around 450 nm are externally wavelength stabilized by external transmitting volume Bragg gratings. Subsequent single-pass nonlinear frequency conversion of such light sources is applied to generate UV laser emission available for corresponding applications such as Raman spectroscopy.

Potential applications

  • Excitation light sources for Raman spectroscopy and absorption spectroscopy

Realized wavelengths

  • 450 nm (external cavity diode laser)
  • 225 nm (UV generation)

Technology and packaging

  • In-house developed packaging
  • Active alignment and mounting of optical components for wavelength-stabilized laser emission
  • Non-linear frequency conversion in single-pass configurations

Typical specifications

  • 1.4 W at 445 nm by external cavity GaN-based diode laser
  • 160 µW by single-pass nonlinear frequency conversion GaN diode laser

The development of the diode lasers was funded by the Einstein Foundation Berlin in the project HautScan (Duration: 01.08.2012 - 31.07.2015).