Reducing laser circuit design load while improving distance measurement accuracy

ROHM’s newly developed VCSEL technology attains greater accuracy in spatial recognition and distance measuring systems by employing TOF systems.

The VCSEL module technology has become prevalent in recent years with the adoption of laser light sources for spatial recognition in tablets and facial recognition on smartphones. With the emergence of AGVs and industrial inspection systems using gesture and shape recognition, the demand for VCSEL is predicted to increase.

Traditionally, in VCSEL-equipped laser light sources, the VCSEL device and MOSFET for driving the light source are separately mounted on the board. Therefore, the wiring length (parasitic inductance) between products has an unintended effect on the light source output and drive time – making it challenging to acquire a light source that delivers the high output and short pulses required for high accuracy sensing.

The new VCSEL module technology developed by the company makes it possible to modularise the VCSEL and MOSFET elements into a single unit. By minimising the wiring length between elements, the performance of every element is maximised, providing a light source capable of short pulse drive (under 10ns) that decreases susceptibility to external noise from sunlight while facilitating up to 30% higher output over conventional solutions.