IEDM 2019: Sony 48MP All-Pixel PDAF Sensor

Sony paper at IEDM 2019 presents "A 1/2inch 48M All PDAF CMOS Image Sensor Using 0.8µm Quad Bayer Coding 2×2OCL with 1.0lux Minimum AF Illuminance Level" by T. Okawa, S. Ooki, H. Yamajo, M. Kawada, M. Tachi, K. Goi, T. Yamasaki, H. Iwashita, M. Nakamizo, T. Ogasahara, Y. Kitano, and K. Tatani.

"Currently, there are two coding trends in mobile image sensors: Quad Bayer coding (QBC) and dual photodiode (DPD). QBC realizes high resolution and high dynamic range (HDR), whereas DPD achieves high phase detection auto focus (PDAF) performance. We propose a QBC with 2×2 on-chip lens (2×2OCL) architecture as a potential next-generation high-performance CMOS image sensor. This combines high resolution, HDR, and high PDAF performance in one sensor. The critical issues of 2×2OCL are degradation of the resolution due to the sensitivity difference between 4 pixels under the same color filter and increasing the crosstalk among different colors. To overcome these issues, the OCL and pixel isolation shapes were optimized respectively. The world`s first image sensor using 2×2OCL architecture we prepared in this paper, has 1/2 inch 48M pixels with 0.8µm QBC for high resolution, and all pixel PDAF achieved a minimum AF illuminance level of 1 lux."