Recently, Apple has launched iPad pro which is the first device to use Lidar scanner.This is also the first Apple device to feature a LiDAR scanner.
About Lidar technology:
LiDAR stands for light detection and ranging.
- LiDAR was first used on a spacecraft during the Apollo 15 mission in 1971, when astronauts mapped the surface of the moon.
- It is basically a remote sensing method that uses light in the form of a pulsed laser to measure distances to the subject.
- A LiDAR sensor fires off beams of laser light and then measures how long it takes for the light to return to the sensor.
- The basic mechanism is known as “time of flight” measurement in which a laser beam is emitted towards an object, reflected off of the object and then collected in a sensor located within the LiDAR module.
- Provide more information: These light pulses – when combined with other data, generate accurate, high-resolution three-dimensional information of the object.
Type of signal used in SONAR and RADAR :
Sonar and Radar too can reveal information about an object’s shape, size, direction and height.
- SONAR on sound waves: Sonar (short for sound navigation and ranging) relies on sound waves to detect objects and hence is usually used to detect objects underwater.
- Radio waves more efficient than sound waves: Radar (short for radio detection and ranging) uses radio waves to determine an object’s distance or range.
- Radio waves can work over a long distance and perform better in dusty conditions.
How is Lidar better?
- Radar can plot the location of a vehicle from miles away, the location can only be known as a featureless “blip”.
- The laser precision of LiDAR can visually map individual features of a vehicle or an environment in what is known as a “point cloud,”.
- The LiDAR sensor provides continuous 360 degrees of visibility and accurate depth information.
Application of lidar technology:
- LiDAR is used to collect high-density data in order to produce high-resolution maps.
- Ground based surveys and aerial surveys: LiDAR sensors are being fitted under drones to create readings of the terrain, transmission lines, buildings, and trees.
- LiDAR is currently being used to provide 3D maps of the ground beneath.
Use of LiDAR in iPad Pro:
- Custom LiDAR scanner used in iPad: slightly more advanced than a ToF(Time of Flight) sensor system.
- The new LiDAR sensor can measure an object up to five meters (16 feet) away. In contrast, a ToF sensor on existing smartphones can only detect objects at a maximum distance of around two metres.
- It can operate “at the photon level at nano-second speeds.”
- It will immensely benefit Augmented Reality (AR) apps: AR refers to a technology that overlays information and virtual objects on real-world scenes in real-time. It uses the existing environment and adds information to it to make a new artificial environment.
- iPad Pro is useful to create future applications. The system takes advantage of “ARKit,” a toolkit for developers to create powerful AR apps.
Disadvantage of LiDAR:
- LiDAR can measure the distance to surrounding objects up to 5 meters away, but won’t fare well in identifying objects in the vicinity.
- It can’t perform well in fog, rain, snow and dusty weather.
- Need secondary cameras: LiDAR also struggles to detect a glass wall or door, which is why smartphone manufacturers and self-driving cars makers use LiDAR along with secondary cameras and sensors.
Image Source: theverge.com