A barcode scanner works by shining a laser beam of red light (around 650 nm wavelength) onto a barcode. The scanner detects the reflected light, interprets the pattern of dark and light bars, and converts it into a digital signal.
The scanner produces a focused laser beam (usually from a laser diode). This light falls on the barcode, which consists of alternating black (dark)and white (light) bars of different widths.
Black bars absorb most of the light, while white spaces reflect it. A photodiode or image sensor inside the scanner detects this reflected light.
The sensor observes changes in light intensity, and these variations correspond to the pattern of bars and spaces in the barcode.
The analog light signal is converted into a digital signal using an ADC (Analog-to-Digital Converter). The digital signal is then processed by the scanner’s decoder, which converts it into numbers or characters based on the barcode pattern.
The decoded information is sent to a computer, POS system, or any connected device for further use (billing, product identification, etc.).
LiDAR (Light Detection and Ranging) works by emitting laser pulses toward an object or surface. These pulses reflect back to the sensor, and the system measures the time taken for the light to return. Using this time-of-flight information, LiDAR calculates the distance and generates a 3D map of the surroundings.
A LiDAR transmitter emits rapid laser pulses, usually in the near-infrared region. These pulses travel outward and hit objects in the environment.
The emitted laser pulses strike objects and reflect back toward the LiDAR sensor. The reflected light carries information about the object's position.
LiDAR measures the time taken for the laser pulse to return. Using the formula Distance = (Speed of Light × Time) / 2, the exact distance to the object is calculated.
A rotating mirror or scanning mechanism sweeps the laser beam across the area. This collects thousands to millions of distance points per second, forming a point cloud.
The collected point cloud data is processed to create 3D maps, elevation models, obstacle detection data, or environmental measurements. The results are sent to computers, robots, drones, or autonomous vehicles for further analysis.
a) Reflection of light
b) Laser diode
b) Reflect light
b) Photodiode / Sensor
b) Reading product information
b) Time of flight of laser pulses
b) Infrared or visible laser light
b) Autonomous vehicles
b) Time taken for the reflected pulse to return
b) 3D point cloud maps