TOF Lidar system demonstration with imec optical beamformers

More than two weeks ago

System demo and modelling of future on-chip Lidars


Time-of-Flight (ToF), Light Detection and Ranging (LiDAR) is a surveying method that measures the distance to a target by illuminating the target with pulsed laser light and measuring the reflected pulses with a sensor as shown in the Fig. 1 (a).  The application of this technology is enormous like autonomous cars, AR, VR, medical imaging and many more. There are mainly two different Lidar types measurements one Frequency Modulated Continuous Wave (FMCW) and the other is ToF.  In FMCW a laser source transmits a frequency-modulated optical wave, which is reflected by a target surface. The beat frequency on the receiver photodiode encodes distance to the target as shown in Fig. 1(b).



Fig 1: (a) ToF and (b) FMCW Lidar


In this project, the student will build the measurement setup and demonstrate the ToF and or FMCW LiDAR system with imec solid-state beamformers.  Imec develops an on-chip optical phased array (OPA) based beamformers which are comprised of low-loss waveguides, phase shifters, leaky wave antennas that can guide light, manipulate the phase and couple out of the in visible and near-IR wavelength regime. It is based on Silicon and or Silicon nitride integrated photonics platform [2, 3, 4]. One such OPA is shown in the Fig. (2). The demonstration includes ranging experiments.

We acquired Aurea Setup that includes high power pulse laser and sensitive avalanche photodetector which can count photons that is required for sensitive measurements like ToF.



Fig 2: One of the fabricated Imec Si-SiN OPA [3]

We acquired Aurea Setup that includes high power pulse laser and sensitive avalanche photodetector which can count photons that are required for sensitive measurements like ToF.

The student can distribute his/ her workload as follow:


1)    Literature survey: 5%

2)    System modelling: 15%

3)    ToF setup building and ranging experiments in free space with Aurea setup: 15%

4)    ToF ranging experiments with imec beamformers using Aurea setup: 40%

5)    Data analysis and weekly reporting: 15%

6)    Thesis/ report writing: 10%




[3] S. Dwivedi et al., OSA Advanced Photonics Congress (AP), 2019, IM4A.3

[4] J. Kjellman et al., IEEE Integrated Photonics Conference, 2019


 Lidar example


Type of project: Internship, Thesis

Duration: 6 months

Required degree: Master of Engineering Technology, Master of Science, Master of Engineering Science

Required background: Nanoscience & Nanotechnology, Electrotechnics/Electrical Engineering, Materials Engineering, Electromechanical engineering

Supervising scientist(s): For further information or for application, please contact: Sarvagya Paavan Dwivedi ( and Marcus Dahlem (

Imec allowance will be provided.

Share this on


This website uses cookies for analytics purposes only without any commercial intent. Find out more here. Our privacy statement can be found here. Some content (videos, iframes, forms,...) on this website will only appear when you have accepted the cookies.

Accept cookies