What is the "engine technology" of LiDAR?

Point frequency is a more comprehensive and comprehensive indicator that reflects the perception ability of LiDAR than FOV, resolution, and refresh rate, just like the "100 km/h acceleration" of a car.

Overall, compared to scanning modules, the transceiver module is the "engine technology" in the LiDAR industry.

The chip based electronic components of the transceiver module are the development trend and technological barrier of future LiDAR.

All hard technology industries have their own technological barriers, and the enterprises that build the highest technological barriers will have an advantage in the competitive landscape, thus "those who gain barriers will gain the world.".

In the era of traditional fuel vehicles, the technological barrier at the "killer card" level of various car companies is undoubtedly engine technology. Developing new engines often takes a long time and is difficult, but despite this, major car companies have invested a lot of resources to improve their engine technology.

Car companies are willing to continuously invest in engine technology, and doing this "difficult but correct" thing is nothing more than building and strengthening their own technological barriers.

So, in the field of LiDAR, what are the core technological barriers similar to engine technology in the automotive industry?

Before answering this question, we need to clarify one question: what are people concerned about when discussing LiDAR?

The actual users of LiDAR are only concerned about three points: performance, reliability, and cost
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Performance generally refers to parameters such as ranging ability, accuracy, field of view angle, resolution, refresh frame rate, volume, power consumption, etc. Reliability refers to whether it can meet vehicle specifications, while cost is a key factor determining whether LiDAR can be mass-produced on a large scale.

Of course, different scenarios have different requirements and preferences for the use of LiDAR:

Robotaxi has extreme performance requirements and high reliability requirements, so it generally uses high beam and high-performance LiDAR;

Low speed enclosed L4 autonomous driving scenarios (such as ports, sanitation, mines, etc.) generally use low beam LiDAR, which requires high cost and reliability;

The ADAS scenario is also gradually starting to pre install LiDAR, which has very high requirements for performance, reliability, and cost.

Velodyne, as a representative of early mechanical LiDAR, has excellent performance, but it is expensive, complex to assemble, and difficult to mass produce. It is also difficult to achieve breakthroughs in product reliability. In order to solve the problems of cost and mass production reliability, various LiDAR manufacturers have explored various aspects such as laser transceiver modules and scanning modules, and have also introduced a series of technical path terms such as MEMS, OPA, solid-state, hybrid solid-state (semi-solid), VCSEL, SPAD, etc.


It is worth emphasizing that whether it is a rotating mirror, prism, or MEMS micro mirror, it essentially changes the direction of light propagation through mechanical moving components to achieve scanning. Therefore, strictly speaking, these types cannot be called "solid", but should be defined as "mixed solid" or "semi-solid". The differences between these types will be discussed in detail in the following text.

Given the current confusion surrounding discussions on LiDAR, let's first provide a brief overview.

Lidar can be divided into ToF and FMCW based on the principle of ranging, with the ToF route being the mainstream technical solution adopted by most manufacturers.

The LiDAR based on the ToF principle can be divided into transmission module, reception module, scanning module, and digital processing module according to its components.

Among them, the transmission module, reception module, and scanning module have significant differences in the technical routes of different LiDAR manufacturers. Currently, the discussion in the industry about hybrid solid-state and solid-state LiDAR is mainly focused on the scanning module, which is the red part in the upper left corner

Summary of ToF LiDAR Components and Technical Roadmap


Returning to the structure of LiDAR, the transmitting module and receiving module are closely related, which we collectively refer to as the transmitting and receiving module. Its function is to emit laser through the laser, and the detector receives the returned light. It is a photoelectric conversion+complex signal processing module, essentially an electronic component.

The scanning module essentially achieves the requirement of covering field of view (FOV) with limited transmission and reception channels by continuously changing the direction of light propagation. It can be likened to a machine gun on a tower defense that needs to counter enemy attacks from all directions. If ten thousand arrows cannot be fired at once, the machine gun must be swung to cover a wider area.

Both mechanical and hybrid solid-state scanning methods achieve scanning by continuously changing the direction of light propagation through mechanical motion.

So, mechanical LiDAR is mechanical scanning, and hybrid solid-state LiDAR is also mechanical scanning.


Based on the above information, we know that LiDAR mainly includes a transceiver module and a scanning module. Currently, discussions in the market mostly focus on scanning, with the most controversial being the differentiation based on scanning methods such as mechanical, hybrid solid-state, and solid-state. Furthermore, in the hot hybrid solid-state solutions, MEMS micro mirrors, rotating mirrors, one-dimensional scanning, and two-dimensional scanning have been derived.