Laser Facts #03: 3D sensing solutions (II)
Introduction to 3D vision sensing solutions (II)
Here is the latest part of the introduction to different systems and technologies to achieve 3D vision and depth sensing through optical solutions.
3) Time-of-flight (ToF)
The Time-of-flight Technology (ToF) is not only used in the field of optics, but also with microwaves or sound waves. It refers to the method of measuring a distance by emitting a signal, and calculating the time of its reflection on an object to be detected by a sensor. Knowing the time difference between the emission and the reception, as well as the speed of the signal, gives a direct relation to the distance of the object.
This calculation is for example already used in our laser distance measurement sensors and rangefinder modules, but for one single point of measure.
(Source EET Taiwan)
In order to achieve 3D vision with the ToF, a whole surface is considered instead of a single point. A larger laser source is projected, and multiple measurement are made. With additional computing, a profile of the object in front of the light source can be fully calculated and output with different types of rendering: Amplitude, Depth of Field, Gray Scale or Point Cloud.
Example: Rendering of the Depth of Field using Egismos 3D ToF Module:
Range: 0.3 meters to 5 meters
Main Applications: Industrial automation, Autonomous Navigation, Security, Face recognition, Medical, IoT