Laser chips are one of the core components in optical communication and lidar systems. Although both rely on laser technology, laser chips used in optical communication and lidar differ significantly in design and characteristics due to differences in their application scenarios, performance requirements, and operating principles. The main differences are as follows:
Laser chips are one of the core components in optical communication and lidar systems. Although both rely on laser technology, laser chips used in optical communication and lidar differ significantly in design and characteristics due to differences in their application scenarios, performance requirements, and operating principles. The main differences are as follows:
1. Laser wavelength
Optical communication laser chip :
l Lasers used in optical communication systems typically operate in the 1550nm and 1310nm wavelength range. This is because optical signals at these wavelengths experience less propagation loss in optical fibers, making them suitable for long-distance transmission.
l The 1550nm wavelength has low attenuation and is compatible with common optical fiber materials such as single-mode fiber, so it is widely used in long-distance, high-speed data transmission.
LiDAR laser chip :
l The wavelengths commonly used in lidar are quite diverse, including 905nm , 1550nm and 1064nm .
l Because lidar requires high-precision ranging, it often chooses lasers with shorter wavelengths (such as 905nm) to achieve better resolution and shorter pulse widths.
l 1550nm wavelength lidar has become a popular choice due to its relatively safe eye safety standard (Class 1), especially in the field of autonomous vehicles.
2. Laser power
Optical communication laser chip :
l Laser chips used in optical communication typically require low output power, generally in the milliwatt (mW) range. This is because optical communication transmits data streams rather than detecting reflected signals, hence the lower power requirements.
l Power stability and modulation performance (such as modulation bandwidth) are key elements in laser design for optical communication systems.
LiDAR laser chip :
l The lasers in lidar typically require higher output power to ensure that the laser signal can cover a longer distance and be reflected back. The laser power is usually several watts (W) or even higher.
l High-power lasers can ensure that the laser beam is effectively reflected over a wide area and provide accurate distance measurement data.
3. Laser pulse width
Optical communication laser chip :
l In optical communication, lasers typically employ continuous wave (CW) mode, meaning they continuously emit optical signals. Their signal waveforms are stable, making them suitable for long-term data transmission.
l The modulation method (such as intensity modulation and phase modulation) determines the transmission capability and bandwidth of optical communication lasers.
LiDAR laser chip :
l The lasers in lidar systems typically employ pulsed laser technology, which involves emitting concentrated, high-energy light pulses over a short period. The pulse duration is extremely short, usually on the order of nanoseconds (ns), to ensure that detection and reflection can be completed in a short time.
l Pulsed lasers help measure the precise distance to targets and support higher-precision 3D scanning.
4. Beam divergence angle and focusing performance
Optical communication laser chip :
l Optical communication lasers typically require very small beams of light to transmit signals through optical fibers, and therefore usually have small divergence angles and high focusing capabilities.
LiDAR laser chip :
l LiDAR needs to scan the surrounding environment extensively with a laser beam, so it needs to be designed with a large divergence angle to ensure that the LiDAR can detect objects over a wide area.
l LiDAR also needs to have strong focusing performance to ensure accuracy at long distances.
5. Cost and Packaging
Optical communication laser chip :
l Due to the large market demand and mature technology of optical communication, the manufacturing process and material costs of optical communication laser chips are relatively standardized. They typically use semiconductor materials such as InGaAs and have relatively simple packaging.
l Optical communication laser chips typically require high-precision temperature control and stability design to ensure reliable data transmission over long periods.
LiDAR laser chip :
l The cost of lidar lasers is relatively high, especially high-power, high-precision lidar chips, which require complex manufacturing processes.
l The packaging technology has high requirements, and it is necessary to consider the focusing and scattering effects of the laser beam, as well as ensure heat dissipation management during long-term high-power operation.
6. Security Requirements
Optical communication laser chip :
l Because optical communication lasers typically have low power, the requirements for eye safety are relatively lenient.
l Most optical communication lasers operate in the low-power range, typically Class 1 lasers, and will not cause harm to the eyes.
LiDAR laser chip :
l LiDAR lasers have high power, especially for long-distance detection and wide-area scanning, therefore they must meet stringent eye safety standards. Some LiDAR systems use lasers that meet Class 1 or Class 3R safety standards to ensure that users are not harmed within normal operating distances.
Summarize
Although both optical communication lasers and lidar lasers rely on laser technology, their core difference lies in their application requirements. Optical communication lasers prioritize power control and long-distance data transmission, while lidar lasers require high power, short pulses, and wide-angle emission to provide accurate spatial ranging and environmental detection capabilities. Selecting the appropriate laser chip is crucial for ensuring system performance, stability, and security.
