Multispectral image sensor combines colour and NIR imaging

This optical filter integration platform will enable many different application fields from medical, industrial, security surveillance, automotive to virtual and augmented reality, where near-infrared signals need to be extracted and overlaid on top of colour images.

Imec claims that its RGB-NIR multispectral platform demonstrates for the very first time the possibility to integrate together standard RGB colour filters, NIR-cut filter, NIR narrow band-pass filters and on-chip microlenses technology, down to small pixels as small as 5µm. The NIR band-pass filter and design pattern implementation can be tuned to match requirements of a specific application case, e.g. the wavelength of a particular laser or LED light.

“An affordable, high resolution and high speed solution for integrating true RGB colour combined with narrow-band NIR detection was essential to develop for future applications that need to detect or track near infra-red signals that should not be visible to human eyes” explained Andy Lambrechts, Programme Manager for imec’s integrated imaging activities. “This capability to integrate a colour view with one or several near-infrared narrow bands will be a key enabler for next-generation 3D, Virtual Reality (VR) & Augmented Reality (AR) imaging platforms. As well as in machine vision, medical, automotive and security surveillance applications.”

Leveraging imec’s background in CMOS scaling, its semiconductor fab, equipment and process technology, imec designs and manufactures interference based optical filters at wafer level, deposited and patterned directly on top of the CMOS image sensor pixels. Imec’s infrastructure provides integrated, clean (class 1 – particle free) and high yield optical filter integration with strong potential for scalability in high-volume.

The first image sensor and camera prototypes will be demonstrated at SPIE Photonics West in San-Francisco on booth 4333 (North Hall of Moscone centre). They are already available for early sampling and evaluation by strategic partners.

Measured QE responses of RGB and NIR spectral channels (microlenses array post-processed on top of each filter)