Autonomous Driving Systems

ADAS Technology

Lidar Sensors in Autonomous Driving

3 min
Where cameras may struggle with glare or low light, lidar continues to deliver consistent structural data.

As vehicles become more automated, they must sense and interpret the world with extraordinary precision. Lidar has emerged as one of the most capable tools for this task. This article explores the technology and its growing importance.

Lidar sensors use laser pulses to capture a vehicle’s surroundings with high accuracy. They enable reliable real-time perception and form a key safety layer in autonomous driving, complementing cameras and radar systems. Lidar creates a three-dimensional representation of the environment by measuring how long laser pulses take to return from surrounding objects.

The result is a dense and highly reliable depth map that remains stable even when light conditions are far from ideal. This capability gives autonomous systems the spatial awareness they need to identify lane markings, spot pedestrians or cyclists and judge distances with confidence. Where cameras may struggle with glare or low light, lidar continues to deliver consistent structural data. The industry is already signalling the shift—“We are moving to a stage where millions of cars sold annually are equipped with lidar,” says David Li, CEO of the Chinese Hesai Group.

The Fundamentals: How Lidar Measures Distance with Light

At its core, lidar uses the time-of-flight principle. A laser pulse is emitted, travels through the air, strikes a surface and returns to the sensor. Because the speed of light is fixed, the distance to the object can be calculated from the round-trip time.

In practice, thousands to millions of such pulses are emitted every second. The sensor’s processing unit interprets these returns and constructs a point cloud – a detailed spatial snapshot that autonomous driving software can analyse in real time. Modern automotive lidar systems achieve millimetre accuracy, which is vital when navigating at speed or in dense traffic.

Strengths That Make Lidar Indispensable

Autonomous vehicles cannot rely on a single sensor type. However, lidar provides several advantages that other technologies alone cannot match:

· Depth data that is both precise and directly measured

· Stable performance in poor lighting or at night

· Clear object outlines, even at long distances

· High-resolution perception useful for predicting movement

· Rapid updates that support immediate braking or steering decisions

These strenghts make lidar particularly valuable for automated functions from Level 3 upwards, where the vehicle takes over crucial driving responsibilities. A safe automated vehicle combines multiple perception systems to reduce blind spots and misinterpretation. Lidar contributes reliable depth information, but only in combination with other sensors does a fully robust environmental model emerge.

By fusing these data streams, vehicles gain both redundancy and clarity. If one sensor is challenged by weather or unusual lighting, another fills the gap. This approach significantly increases the safety margins required for higher levels of automation.

Cost Reductions and Engineering Challenges

Historically, lidar was associated with high costs and bulky mechanical components. Early systems rotated continuously to achieve a 360-degree view, which made them expensive, fragile and impractical for mass-market vehicles.

The industry has since shifted towards solid-state designs. These sensors have no moving parts, are cheaper to produce, occupy less space and offer better durability. As manufacturing volumes grow, prices continue to fall and integration becomes more realistic even for mid-range vehicles.

Still, practical challenges remain. Lidar systems must be aligned carefully with vehicle software, draw manageable amounts of power and work reliably for hundreds of thousands of kilometres. Thermal management, cleaning systems and mounting positions must also be considered to avoid performance degradation.

Who Uses Lidar Today: Automotive and Technology Pioneers

Several manufacturers and technology firms have already integrated lidar into their automated driving strategies:

· Mercedes-Benz offers lidar-based Level-3 functions in some markets

· Volvo equips selected models with roof-mounted lidar for enhanced safety

· Waymo operates autonomous robotaxis using proprietary lidar sensors

· Luminar develops automotive-grade lidar systems for several brands

These deployments demonstrate not only technical feasibility but also growing acceptance of lidar as a foundational sensor for safe automation.

Where Lidar Technology Is Heading

Lidar’s development trajectory is clear: sensors are becoming smaller, more energy-efficient and more deeply integrated into the vehicle’s software stack. Improvements in neural-network-based perception allow systems to extract more meaning from lidar point clouds, improving object recognition and prediction accuracy.

Looking ahead, lidar is expected to play an essential role in Level-4 and Level-5 automated systems, where vehicles must understand their surroundings with almost human-level nuance. With each advancement in hardware and machine learning, lidar becomes more capable of supporting autonomous vehicles in complex and unpredictable environments.