ROHM has integrated VCSEL technology with MOSFET drivers in a module to achieve the shorter pulses and high output required for more accurate sensing.

Conventionally, in VCSEL-equipped laser light sources, both the VCSEL device and MOSFET for driving the light source are individually mounted on the board. Consequently, the wiring length (parasitic inductance) between products has an unintentional effect on the light source output and drive time – making it difficult to achieve a light source that provides the high output and short pulses needed for high accuracy sensing.
ROHM’s VCSEL module technology makes it possible to modularize the VCSEL and MOSFET elements into a single package.
By minimizing the wiring length between elements, the performance of each element is maximized, resulting in a light source capable of short pulse drive (under 10ns) that reduces susceptibility to external noise from sunlight while enabling up to 30% higher output over conventional solutions.

As a result, when evaluating ROHM’s VCSEL module technology in spatial recognition and ranging systems comprised of a control IC, TOF sensor (light receiving element), and laser light source (VCSEL module), the amount of light reflected to the TOF sensor is claimed to be increased by 30% over conventional configurations, contributing to improved accuracy in TOF systems.
ROHM plans on releasing its new VCSEL module in March 2021 for AGVs in the industrial market and facial recognition systems for mobile devices requiring high accuracy sensing. The company will also continue to develop high output lasers for LiDAR in vehicles and other applications.