Chuo University Team Developed High-Efficiency Color Path Device, Support Image Quality

｜ TechNews Emma Stein

As market demand for high-resolution imaging continues to rise, color image sensors are facing performance challenges due to the continuous shrinking of pixel sizes. Recently, a team from National Central University successfully overcame key bottlenecks in color imaging sensor technology by developing a high-efficiency color router, which not only helps reduce manufacturing costs but is also expected to significantly enhance sensing performance at submicron pixel scales.

Hero image placeholder｜National Central University team develops high-efficiency color router to enhance imaging quality

Sensing bottlenecks under pixel miniaturization

Color image sensors are core components of imaging technology. As individual pixel sizes shrink from 1.6 micrometers to 0.8 micrometers and continue toward next-generation 0.56 micrometer technology, the energy flux entering a single pixel through color filters decreases significantly, increasing the difficulty of achieving high-resolution image sensing.

Limitations of traditional microlens performance

At submicron scales, diffraction effects become more pronounced, gradually reducing the optical focusing capability of traditional wafer-level refractive microlenses. To address this technical bottleneck, “color router” technology—capable of precisely directing color signals to adjacent pixels—has emerged as a key solution. However, existing approaches often rely on advanced processes below 65 nm, resulting in high costs and manufacturing barriers.

A high-efficiency solution built on 0.18 μm process

The research team led by Professor Wang Zhiming at the Department of Optics and Photonics, National Central University, together with its spin-off startup MetaRosetta, successfully utilized a mature 0.18 μm semiconductor lithography process combined with self-developed electromagnetic simulation and AI optimization technologies to develop a high-efficiency color router with optical efficiency exceeding 120%, providing a more cost-effective solution for high-resolution image sensors.

Expanding potential for intelligent imaging and sensing applications

This technology can be widely applied in smartphones, high-end cameras, autonomous vehicle imaging sensors, as well as medical diagnostic equipment and AR/VR devices. By integrating the high-efficiency color router, even under extremely small pixel conditions, it is possible to obtain images with accurate colors and rich details, improving photo quality, enhancing machine vision accuracy, and advancing imaging sensor technology toward higher resolution and lower power consumption.

Research recognized by international journals

The research results have been published in ACS Photonics and selected as a supplementary journal cover, demonstrating the research value and international visibility of this technology in the field of optical sensing.