A new CMY camera technology using Al-TiO2-Al nanorod filter mosaic integrated on a CMOS image sensor

TL;DR

This paper introduces a CMOS-compatible nanoscale CMY colour filter mosaic made of Al-TiO2-Al nanorods, enabling improved low-light imaging and integration on image sensors for various applications.

Contribution

It presents a novel nanoscale CMY filter mosaic using nanorods, integrated on a CMOS sensor, overcoming fabrication challenges of traditional pigment-based filters.

Findings

Successfully fabricated a 0.82 million pixel CMY mosaic

Integrated the mosaic onto a CMOS sensor and demonstrated colour imaging

Potential applications in astronomy, biology, and photography

Abstract

A CMY colour camera differs from its RGB counterpart in that it employs a subtractive colour space of cyan, magenta and yellow. CMY cameras tend to performs better than RGB cameras in low light conditions due to their much higher transmittance. However, conventional CMY colour filter technology made of pigments and dyes are limited in performance for the next generation image sensors with submicron pixel sizes. These conventional filters are difficult to fabricate at nanoscale dimensions as they use their absorption properties to subtract colours. This paper presents a CMOS compatible nanoscale thick CMY colour mosaic made of Al-TiO2-Al nanorods forming an array 0.82 million colour pixels of 4.4 micron each, arranged in a CMYM pattern. The colour mosaic was then integrated onto a MT9P031 monochrome image sensor to make a CMY camera and the colour imaging demonstrated using a 12 colour Macbeth chart. The developed technology will have applications in astronomy, low exposure time imaging in biology and photography.