It’s called Isocell — and the new advanced pixel technology for CMOS image sensors from Samsung Electronics “substantially increases light sensitivity and effectively controls the absorption of electrons, resulting in higher color fidelity even in poor lighting conditions,” the company says.
Isocell forms a physical barrier between neighboring pixels, and this pixel isolation “enables more photons to be collected from the micro-lens and absorbed into the correct pixel’s photodiode minimizing undesired electrical crosstalk between pixels and allowing expanded full well capacity,” Samsung claims.
The quality of an image sensor is determined by the amount of light that is accurately captured by the individual pixels within the sensor array, Samsung notes. “With the market pressure to increase camera resolution and image quality, without growing the camera size, the pixels have had to shrink, while improving their performance at the same time – a challenging task. To meet this challenge, previous sensor technology developments focused on improving the light absorption of each pixel, and have progressed pixel technology from FSI (Front Side Illumination) to BSI (Back Side Illumination) which places photodiode at the top to maximize photoelectric efficiency. While being very effective at the time, this BSI technology also faced limitations in improving image quality as pixel sizes continued to decrease.”
Compared to conventional BSI pixels, the Isocell pixels decrease crosstalk by approximately 30 percent, the company reports, yielding higher color fidelity, and increases the full well capacity (FWC) by 30 percent which leads to greater dynamic range. It can also result in thinner camera module thanks to a 20 percent wider chief ray angle.
Samsung is currently sampling an 8-megapixel imager with the new technology. It notes market research firm Techno System’s claim that by next year approximately 66 percent of smartphones will feature image sensors with 8Mp or higher resolution.