High-power laser diodes (HPLDs) are an emerging technology that continues to break the barriers of what is possible in advanced, high-power systems. Whether it’s industrial manufacturing, medical and sensing applications, or clean fusion energy, HPLDs stand out as a key technology.
The question is, what is driving the innovation of this technology forward? At the heart of this development are five key drivers:
- Higher optical power and efficiency
- Higher brightness
- Smaller size and weight
- Improved reliability
- Lower cost
The most widely used type of high-power laser diode (HPLD) is broad-area, edge-emitting laser diodes. Currently, they stand as the most efficient light source available. These lasers are built using highly precise manufacturing techniques. Despite all of these improvements to the design of HPLDs, challenges remain.
HPLD technology faces many challenges, including beam brightness and heating and cooling issues. First, low brightness is a major problem as the light that comes out of the diode spreads too quickly and requires another laser (i.e., a fiber laser or solid-state laser) to refocus the beam. Second, high-power systems often create issues with overheating. Parts can degrade or fail with improper cooling systems. Keeping the system cool while also maintaining a low size and weight is difficult. In fact, the interconnectedness of the five drivers creates a delicate balance. When one driver is improved, another may pay the price.
The ideal would be using the diode itself instead of as a vehicle for another laser system. In order to do this, we need high-brightness and high-quality laser diodes. Some intriguing diode architectures have come out of this pursuit, including PCSELs and edge-emitting, tapered, single-mode ridge waveguide lasers.
The five drivers continue to push forward HPLD advancements. While remarkable progress has been made, the future holds even more technical breakthroughs. With physical limitations coming into play, engineers may soon hit a wall. As the industry continues to improve scalability and manufacturing efficiency, emerging applications and changes in existing markets will continue to push forward the future of HPLDs.
Want to learn more? Check out our article in Photonics Spectra.