Sequential RGB color imaging with a millimeter-scale monochrome camera with a rolling shutter.

Area of Science:

• Optics and Photonics
• Micro-optics and Imaging Systems
• Computer Vision

Background:

• Millimeter-scale cameras are crucial for compact imaging applications.
• Bayer color masks degrade resolution and image quality in small sensors.
• Existing color imaging techniques face limitations in submillimeter applications.

Purpose of the Study:

• To develop an alternative to Bayer color masks for submillimeter cameras.
• To improve image resolution and clarity in ultracompact color imaging.
• To present a time-multiplexed illumination system for enhanced color video.

Main Methods:

• A time-multiplexed RGB LED illumination system was synchronized with a monochrome camera's rolling shutter.
• Sequential images captured under different LED colors were processed.
• The system was experimentally compared against a standard Bayer color mask sensor.

Main Results:

• Significant improvements in Modulation Transfer Function (MTF) curves were observed.
• Enhanced perceived image clarity was demonstrated compared to Bayer mask sensors.
• Near real-time color video output was achieved.

Conclusions:

• Time-multiplexed RGB LED illumination offers a viable alternative to Bayer masks for submillimeter cameras.
• This method substantially improves image resolution and clarity.
• System complexity and potential color motion artifacts are key considerations.