As we all know, a technical topic in ranging and LiDAR is how to improve the signal-to-noise ratio of laser detection, so that perception of LiDAR can be more accurate, sensing distance can be longer. The usual practice is to increase the laser power density or reduce noise (including detector noise and noise generated by ambient light). There are two main ways to increase power density: one is to reduce divergence; the other is to increase optical power. Boosting optical power increases power consumption, so it is an effective way to reduce divergence of laser with same power consumption. Traditional method to reduce divergence is usually by complex optical lens combination, however, it may result in bulky, fragile, and expensive of the system.
Principle of laser ranging sensor
Brightlaser uses SMD packaging technology to encapsulate optical lens on VCSEL bracket, thus greatly reduces product size. Without any extra special optical design, users can accelerate product development, saving R&D costs and time.
In 2020, Brightlaser introduced VCSEL module integrated collimating optical lens. The VCSEL module only 3.5mmX3.5mmX3.5mm, but the divergence (FWHM) can be reduced as low as 3-5mrd. At present, Brightlaser has launched a series VCSEL SMD module in 808nm, 850nm and 940nm, with small size, low divergence, high peak power, effectively improve signal strength, significantly increase LiDAR detection range.
Compared to ~0.3 nm/K of Edge Emitting Lasers (EELs), Vertical Cavity Surface Emitting Lasers (VCSELs) have much smaller wavelength drift with temperature (~0.07 nm/K) ，which does not require additional wavelength stabilization schemes or external optics, while that is a must for EEL. In addition, due to advanced technology of epitaxial growth and packaging, wavelength of large-scale VCSEL 2D arrays is very uniform, with a spectral width of about 0.8 nm, which is significantly lower than that of edge emitters (3 ~ 5 nm), the narrow bandwidth characteristics allow VCSEL to match the specific absorption spectrum; conducive to reducing the interference of ambient light and improving the signal-to-noise ratio.
In terms of reliability, VCSELs have inherent advantages over edge-emitting lasers because VCSELs do not suffer from catastrophic optical damage, and their activation energy is almost twice that of edge-emitting lasers (~0.7 eV). This means that VCSELs can operate reliably at higher temperatures. This advantage is important because VCSEL cooling requirements become less stringent, resulting in more compact laser systems and higher overall efficiency for high-reliability application scenarios such as automotive, aerospace, and more.
Low divergence light sources are also often used in the detection of some special-shaped or complex environments. In order to increase measurement distance and reduce malfunctions, light source must emit a beam with a smaller angle. Optical lenses can be coupled with VCSEL to collimate the output beam, thereby reducing beam divergence.
Brightlaser provides a wide range of SMD collimated VCSEL products for the market. There are 808nm, 850nm and 940nm, from 5mW to 5W, continuous wave and pulsed mode in terms of operating conditions. Modules are with flexible features for the purpose of meeting different scenarios in various applications.
Below is beam profile of 200mW 850nm VCSEL diode in 3535 AlN package integrated with collimating lens.
Below is beam profile of 700mW 850nm VCSEL diode in 3535 AlN package integrated with collimating lens.
In addition to SMD collimated low-divergence VCSELs, Brightlaser also provide below packaged low-cost small angle VCSELs with a minimum angle of 0.75°, which is widely used in short-range data transmission, such as LiDAR internal data transmission, and in various sensors.
Brightlaser is an IDM VCSEL manufacturer with ISO9001 and IATF16949 qualifications. Its products have passed CE, RoHS, REACH and the most stringent AEC-Q102 certifications for automotive grade components. It owns comprehensive production and reliability testing facilities, intensive professional experience and knowhow in product development, sufficient production capacity, which ensure the fastest delivery in VCSEL field, and supply the best cost-effective performance, and the most competitive products and solutions.
Brightlaser was founded in 2014, is a global pioneer supplier in VCSEL technology from components, sensors, to total solutions for AIoT applications including Datacom, Consumer Electronics, ADAS, Industrials, Medicals & Cosmetics, Smart Home etc.
As a high-tech company, Brightlaser possesses its own VCSEL intellectual properties in wafer design, advanced chip process, and applications. Brightlaser headquartered in Hong Kong, established branch offices in Shen Zhen and Zhong Shan of China. The factory located in Zhong Shan covers footprint of 160,000 Sq. ft., equipped with globally state- of-art GaAs techniques, and the first 6-inch VCSEL chip fab & packaging line in mainland China.
In recent years, Brightlaser has caught up extremely quickly with all the opportunities the market has been giving, is becoming increasingly competitive. Currently, we are working with worldwide-leading partners and customers in technologies, marketing, and sales.
To cope with the rapidly growing, we are seeking professional dealers, distributors to join this promising field. As a self-driven, proactive, taking initiative, team player, you are welcome to our fast-paced, dynamic team of collaborators.
