Development Status of CMOS 1920×1080 Imaging System-on-Chip for 60p HDTV

High-performance charge-coupled device imagers (CCD) having 2 million pixels in 1920×1080 format have been commercially available for over ten years¹. Nevertheless, today's HDTV cameras still do not simultaneously provide sufficient resolution and electronic film speed at the minimum progressive frame rates (≥60p) needed for creative motion imaging production. Overcranking, for example, is only available at ∼1 million pixel (1280 by 720) resolution. The maximum frame rate of today's 1920×1080 progressive cameras is 30 Hz. To truly offer a compelling alternative to motion imaging film, electronic HD cameras must provide higher progressive frame rate along with additional bit depth to maximize production quality and creativity. Leveraging a key architectural advantage and ongoing improvements in CMOS technology driven by a robust semiconductor industry that produces multi-GHz microprocessors at consumer prices, CMOS-based image sensors are now more capable than CCDs of meeting this challenge. We discuss the technical background for the shift in technology from CCD imaging to CMOS imaging system-on-chip. Specifically, we compare the sensor architectures and explain why CCD noise consistently increases with video frequency at about 3 dB/octave. Managing noise consequently forces more video outputs per CCD. High-end CCD-based camera manufacturers are consequently building larger, more expensive and more power hungry cameras. We conclude by briefly reporting the development status for a CMOS 1920×1080 image sensor for next-generation, affordable and compact HD cameras to support progressive frame rates at 60 Hz and beyond.

Published

2004-02

Content type

Original Research

DOI

10.5594/M001010

ISBN

978-1-60423-807-5