2 September 2020
SemiNex launches multi-junction 1310-1550nm laser for LiDAR
SemiNex Corp of Peabody, MA, USA - which was founded in 2003 and designs and makes indium phosphide (InP)-based high-power infrared diode lasers for military, medical and industrial applications - has made available product samples of a patent-pending, multi-junction laser diode that emits more than 20 times the photons/second over more than 3x the range at eye-safe wavelengths of 1310-1550nm compared with 905nm light detection & ranging (LiDAR) systems, which should enable mass-market auto-driving cars to finally become a reality. Ready for immediate high-volume production, the multi-junction laser diode is a drop-in replacement for most compact laser drivers used for existing 9XX nm diode systems.
The new laser makes use of three monolithic solid-state laser junctions that produce 80W at 1550nm with 95μm aperture width and yield more than 3x the power of existing laser diodes at this wavelength.
For the past ten years LiDAR manufacturers have taken two laser approaches for time-of-flight LiDAR systems: 905nm laser diodes or 1550nm fiber lasers.
Typical time-of-flight LiDAR systems using multi-junction 905nm lasers are limited to a range of 100m due to the eye-safety acceptable emission limits (AEL) of International Electrotechnical Commission (IEC) regulations. The limited visibility of 100m would require a vehicle’s speed to be 25mph or less. So, 905nm lasers are restricted to niche applications such as private security systems, warehouse automation, and limited-use public driving functionality.
The alternative 1550nm fiber lasers are impractical for mass-market deployment because of their size and cost.
So, until now, there has been no solution that offered the low-cost, small size and efficiency of 905nm laser diodes with the eye-safety and extended range of 1550nm fiber lasers. Neither of these past approaches meet the automotive industry goals to enable LIDAR commercialization. The lack of efficient and inexpensive 200m eye-safe LiDAR has therefore held back the industry from commercializing autonomous vehicles and seeing any meaningful mass-market deployment at speeds greater than 25mph.
“SemiNex invested three years in R&D to create a long-range and cost-effective solution to overcome the short-range limitations of existing technologies,” says CEO David Bean. The new multi-junction laser enables high-power, longer-range (>250m), lower-cost, eye-safe LiDAR solutions for autonomous trains, planes and automobiles.
“Now there is a low-cost, long-range, eye-safe alternative to 9XX nm diodes and 1550nm fiber lasers,” adds director of sales & marketing Ed McIntyre.
The LiDAR market for automotive and industrial applications is expected to be $981m, limited to short-range applications. However, with improvements in technology and broader acceptance, the market is expected to grow to $2.8bn by 2025. A major challenge with the existing LiDAR technology for autonomous vehicles has been to find a cost-effective laser diode that can provide high peak power at eye-safe wavelengths for long-range applications. Operating at 1550nm, the SemiNex triple-junction device provides three times the peak power of a single emitter, improving the resolution and penetration effectiveness in bad weather while remaining eye-safe. It can be operated at pulse widths of 2-100ns at 200-400kHz pulse repetition rate. SemiNex offers multi-junction devices emitting at wavelengths between 1310nm and 1550nm through various aperture widths and with cavity lengths to meet specific customer requirements.
“The SemiNex multi-junction laser diodes will allow vehicles to autonomously navigate at higher speeds that can’t be achieved with the existing technology; this could finally enable driverless cars to be a reality within the next 5 years,” reckons McIntyre.
The multi-junction device is available in double- and triple-junction configurations in various packaging and submount configurations. Samples in either TO-9 or bare die configuration at 1550nm are available for immediate delivery.