6 July 2016

Ricoh develops 200W fiber-coupled 808nm VCSEL module

Assisted partly by the Program for Strategic Innovative Energy Saving Technology run by Japan's New Energy and Industrial Technology Development Organization (NEDO), Tokyo-based Ricoh has developed an 808nm-wavelength fiber-coupled high-power vertical-cavity surface-emitting laser (VCSEL) module that can be used as a light source for the firm's production printers currently on the market as well as in new applications such as engine ignition.

The power output of the VCSEL array is 310W standalone, and 200W with the fiber output module - under quasi-continuous-wave (QCW) drive conditions of 500μs pulse width and 20Hz repetition cycle - which is claimed to be unprecedented for a fiber-coupled VCSEL module.

The high-power VCSEL module is said to incorporate three technical advances: high output performance, compact size, and wavelength stability in variable temperatures.

Ricoh has increased the luminescence efficiency of the VCSELs. It has also achieved large-scale integration of the light-emitting channels. Specifically, the module uses a VCSEL array with a large number of light-emitting channels on its surface, along with a micro lens array (MLA) that integrates lenses corresponding to each light-emitting channel on a single chip. As it has fewer components compared with modules using conventional edge-emitting-type lasers, the VCSEL module is more compact. Altogether, the output power of the laser array is significantly boosted.

By improving the heat dissipation of the overall module, it can now deliver the high energy output needed by the laser crystal light source in a laser ignition plug head. This type of plug head has been attracting attention as a means of igniting gas engines for power generation used in cogeneration systems and other equipment.

Due to its structure, the VCSEL features what is claimed to be exceptional wavelength stability in variable temperatures, offering about ten times the thermal stability in wavelength compared with conventional edge-emitting-type lasers. In solid-state laser excitation used in applications such as the laser crystals of laser ignition plug heads, the wavelength stability of the excitation light is vital to achieving stable output. As a result, a precision temperature control unit is not required, allowing a significant reduction in size of the VCSEL module.

Ricoh is also looking to expand into applications such as laser processing machines, surface treatment processing such as laser patterning, non-thermal processing and sensing, as well as the development of other applications.

Tags: VCSEL

Visit: www.ricoh.com