Time of Flight (ToF)

Time-of-Flight (ToF) is a technique for measuring time taken by an object, particle or wave to travel a distance through a medium. The measurement is based on sending out a light pulse – either from a laser or LED – to measure the reflected pulse. The distance is measured by calculating the time it takes for the light to travel to the object.  

A popular optical application is the use of depth cameras and ToF to take 3D images, which for instance is used in face recognition applications.

There are a few different types of output patterns that are used: sequential projections, continuous varying pattern, stripe indexing, grid indexing and hybrid methods. There are different advantages with the different methods, so it depends on the application. An example is the possibility to require depth information in real time. Then you would capture the information in one single shot, which rules out sequential projections that require multiple shots. A general term for these projection patterns is Structured Light.

When the output projection pattern is compared with the reflected pattern, it is possible to use different algorithms to calculate the change in the phase of light, which in turn is used to determine the time for the light path – or the distance.

 

ToF – Time of Flight and how we can help
We can design, prototype and manufacture DOEs for output projection patterns.

We can work with designs that we have made, or designs provided by our clients.

We offer various novel solutions for light focusing to the sensor chip on the receiver side”

 

Use of ToF – Time of Flight
The number of applications that require depth information of the environment are many. Face recognition, self-driving cars and machine vision are some popular application areas for Time of Flight devices.