Laser Distance Sensors vs Laser Displacement Sensors: What's the Difference?

In fields such as manufacturing, precision instruments, biomedicine, and aerospace, the demand for measurement accuracy and efficiency is steadily increasing. Non-contact, digital, high-precision, and highly sensitive optical measurement sensors, especially laser distance sensors and laser displacement sensors, are providing more precise, efficient, and intelligent measurement solutions across various industries.

The pulse method (ToF) is especially suitable for applications requiring the measurement of long distances or large areas, such as drone mapping, 3D map construction, environmental monitoring (e.g., the vertical distribution of pollutants in the atmosphere), and obstacle detection and avoidance in autonomous vehicles.

The phase-shift method provides higher measurement accuracy than the pulse method (ToF) at medium and short distances, making it an indispensable tool in industrial automation. For example, phase-shift laser sensors play a crucial role in precise positioning of robotic arms, alignment of parts on automated assembly lines, and precision machining in CNC machines.

Triangulation is a geometric measurement method based on triangular relationships. In this method, a laser spot is projected onto the object to be measured, and the reflected light from the object is directed at a certain angle towards the CMOS sensor element. The position of the light spot on the CMOS line changes according to the distance of the object. In this way, even at very small distances, the distance to the object can be precisely determined.

Ultra-short distance high-precision measurement: The triangulation method, known for its extremely high measurement accuracy and stability, is widely used in fields such as electronic component processing, semiconductor manufacturing, and precision machining. It can accurately measure small dimensional changes, such as line widths on chips and dimensional tolerances of components.

Laser displacement sensors typically use the triangulation method. This measurement method can achieve nanometer-level precision, making it suitable for high-precision, short-distance measurements. In current industrial robot applications, triangulation is one of the commonly used techniques, with linearity reaching up to 1 micron and resolution up to 0.1 microns. Laser displacement sensors are commonly used to detect geometric quantities such as displacement, flatness, thickness, vibration, distance, and diameter of objects. These sensors play a crucial role in industrial manufacturing, precision machining, and quality control.

Laser distance sensors usually adopt the pulse method (ToF) or phase-shift method, and due to their suitability for a wider range of distance measurement needs, they are widely used in industrial production automation. These sensors not only meet the requirements for long-distance measurement but also feature high precision and fast response times. In the field of industrial automation, laser distance sensors are extensively used for position control and navigation, contour measurement and surface inspection, safety protection, logistics and warehouse management, as well as automated welding and cutting. They provide reliable distance measurement data for automation systems, helping to improve production efficiency, accuracy, and safety. They also demonstrate unique advantages in emerging fields such as intelligent transportation and autonomous driving.