Short-wave Infrared Light emitters based on Colloidal Quantum Dot Technology

Introduction

Optical sensing and imaging has evolved from taking digital images to a powerful metrology, imaging, and data acquisition technique by expanding the spectral coverage from the visible to the short-wave infrared (SWIR).

Importance of SWIR Sensing

SWIR sensing and imaging is the cornerstone of advanced imaging techniques for:

• 3D visualization
• Night vision
• Imaging through adverse weather conditions
• Biomedical imaging
• Spectroscopy for food quality and health monitoring

These applications highlight the significant market size, especially with the entry into volume markets including consumer electronics and automotive. This demand has led to the first commercial appearances of low-cost CMOS compatible SWIR photodetectors and image sensors.

Challenges in Optical Sources

Yet, for the realization of the aforementioned technologies, the optical source is an equally important and crucial component to be considered at the system level.

Current Limitations

To date, there is a lack of infrared optical sources that are:

1. CMOS compatible
2. Low-cost
3. Competitive in performance compared to standard costly epitaxial III-V light emitters

Moreover, high costs and epitaxial growth manufacturing processes have limited the size and form factor of these sources to small and rigid elements, preventing their use as high power and large area illumination sources.

Project Goals

SWIRL will undertake the challenge to develop high-performance low-cost SWIR optical sources with:

• Tunable emission peaks
• Spectral bandwidths across the eye-safety SWIR window

This will be achieved by exploiting colloidal quantum dot technology.

Methodology

By leveraging engineering at the nanoscale and solution-processed materials, we will develop in TRL4/5 SWIR optical emitters that are:

• Low-cost
• High efficiency
• Capable of rivalling their epitaxial counterparts
• Spectrally versatile across the SWIR

Applications

We will further demonstrate their use in key applications related to the automotive industry as optical sources for:

• Active SWIR imaging
• In-cabin monitoring in the eye-safety infrared window