Samsung has announced its new ISOCELL technology for CMOS image sensors that substantially increases light sensitivity and controls the absorption of electrons for higher colour fidelity in low light scenarios. The technology works towards improving the image quality for smartphone and tablets that integrate sensors with it.
According to Samsung, it felt a challenge when it saw that the market pressure to increase camera resolution and image quality, without growing the camera size. To do so, pixels needed to be shrunk even while the performance has had to be improved. 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 and previous technological developments progressed pixel technology from Front Side Illumination (FSI) to Back Side Illumination (BSI). Even after this, BSI seems to be facing limitations in improving image quality as pixel sizes continued to decrease.
The technology boasts of better low-light pictures
Samsung developed ISOCELL building on these past developments to create a physical barrier between neighboring pixels, thereby isolating the pixel. According to Samsung, this isolation enables more photons to be collected from the micro-lens and absorbed into the correct pixel’s photodiode minimising undesired electrical crosstalk between pixels and allowing expanded full well capacity (FWC).
Compared to conventional BSI pixels, the ISOCELL pixels decrease the crosstalk by approximately 30 percent which results in higher colour fidelity to reproduce the original colour in a sharper manner, and increase the FWC by 30 percent which leads to greater dynamic range.
Touted to be better than BSI
Additionally, says the company, an imager designed with ISOCELL can feature a 20 percent wider chief ray angle (CRA), reducing the height of the camera module, making it suitable for slim and small form factor mobile devices with challenging low z-height requirements.
The S5K4H5YB 8 Megapixel imager is the first image sensor by Samsung to adopt this technology and utilises a 1.12um ISOCELL pixel along with a 1/4inch optical format. The S5K4H5YB is expected to be mass produced in the last quarter of this year, with it being currently tested with a handful of customers.