Many people are curious about what kind of laser Vcsel laser is, and which scenes are it mainly used in? How does it work? Let's take a look at it from the perspective of Xiaobian.

The full name of VCSEL is vertical cavity surface emitting laser, in fact, it is a laser that emits light in the vertical direction. Traditional edge-emitting laser diodes (like EEL) emit light from the edge of the chip, while VCSEL emit Mitsudeki vertically from the front of the chip.

This "light direction" difference, seemingly inconspicuous, is of great significance in engineering. Because the structure of VCSEL is relatively compact, the production process is also easy to make into an array, and hundreds of light-emitting points can be made on a chip, with high efficiency, good heat dissipation and convenient testing.

Working principle of VCsel laser

An active layer is sandwiched between two distributed Bragg reflectors (DBR). After the current passes through, electrons and holes recombine in the active layer, releasing photons, which are reflected back and forth in the cavity, amplified continuously, and then emitted from the upper surface. In other words, its "laser cavity" is vertically stacked inside the chip.

The biggest advantages of VCSEL are good beam quality, uniform energy distribution, low cost and high reliability. I remember a few years ago, we debugged a VCSEL module for a face recognition project, and the customer used a 940nm band VCSEL array. At that time, the most typical application was the 3D face recognition system of mobile phones, such as Apple's Face ID, which used the infrared laser emitted by VCSEL.

In addition to mobile phones, lidar is also the main battlefield of VCSEL. Especially for vehicle-borne radar, it requires the laser module to be small in size, controllable in divergence angle and long in life. VCSEL performs particularly well in these aspects, and it can also emit light in array, and its scanning efficiency is higher than that of traditional EEL. Nowadays, many smart cars are using ToF (Time of Flight) ranging technology based on VCSEL.

The above is the working principle and application of vcsel laser. If you are not clear, you can contact us at any time.