Novel high-brightness diode lasers


High-brightness laser diodes are the driving force behind all modern laser systems, and the key enabling technology for the most advanced scientific and industrial laser applications. The world-record brightness in laser diode modules has recently been demonstrated by Lawrence Livermore National Laboratory (LLNL) and Lasertel Inc, using micro-optics technology from Power Photonic Ltd (UK), which was originally developed by Heriot-Watt University.

Several questions remain that need to be answered with careful design and engineering: How can we use micro-optics to better utilise the highly divergent light emitted by each single diode emitter; How can we best combine many single-emitter beams to produce a combined laser beam; Can we select the optimum wavelengths to pump a particular solid-state laser or fibre laser; Can we design a high brightness laser diode module that is compact and cost-effective using additive manufacturing?

This project is part of the research collaboration between Renishaw PLC, the EPSRC Centre for Innovative Manufacturing in Laser-based Production Processes (CIM-Laser) and Heriot-Watt University. Our target is to design, develop and demonstrate novel laser systems that can be used for future manufacturing applications, including powder bed additive layer manufacturing.

Project description: Novel high-brightness diode lasers

The objective of this project is to develop novel technologies relating to high-power, high-brightness diode laser sources. It aims to develop a new beam combining optical scheme coupled to an additively manufactured (AM) carrier with built-in cooling to accurately and stably mount the diode lasers and optics. Power and brightness scaling will be achieved using custom micro-optics to combine a number of laser diode arrays using spatial, polarisation and wavelength techniques. Scalable, high brightness direct diode power will have a broad range of applications, but in particular machine concepts will be investigated for beam delivery to a metal AM powder bed, to characterise and understand the beam-powder interaction and subsequent melt pool dynamics.


Heriot-Watt is based in a modern environment on the outskirts of Edinburgh, with excellent transport links to the centre of one of Europe’s most exciting cities. Heriot-Watt hosts the EPSRC Centre for Doctoral Training in Applied Photonics, cementing Heriot-Watt’s reputation as a centre of excellence in photonics, and providing PhD students with an even more attractive environment for study, as well as enhanced training opportunities.

Heriot-Watt Institute of Photonics and Quantum Sciences (IPAQS)

IPAQS is a thriving environment for PhD research, having a total of 160 academics, postdocs, PhD and EngD students working full-time in the general photonics field. It’s a friendly collaborative environment where staff and students freely interact -- not least at Friday morning coffee and donut sessions.

Funding Notes

This 4-year project is funded by the EPSRC under an Industrial CASE from Renishaw PLC. The EPSRC total funding is £83,296 to cover the 4 year value of stipend, fees and incidental costs, with a further enhancement from Renishaw. Funding is available only to UK residents, although EU nationals may also be considered under certain circumstances. A substantial consumables and equipment budget is provided by a concurrent EPSRC CIM-Laser grant. Travel funding for conference presentations is also available.


Please send a CV including 2 references to Prof. Daniel Esser at