Image sensor family ultra-low light technologies

It provides these enhancements while maintaining high performance, day and night, for detecting incident light in both the visible and NIR wavelengths to produce even more precise colour and monochrome images.

“In addition to requiring top performance in all lighting conditions, security and surveillance camera designers are demanding higher resolution for greater facial recognition accuracy with longer zoom range,” said Brian Fang, Business Development Director at OmniVision. “By combining our industry-leading NIR and ULL technologies with four megapixel resolution, the OS04A10 is designed to meet the evolving needs of security and surveillance systems.”

OmniVision’s Nyxel NIR technology imparts the OS04A10 with exceptional quantum efficiency (QE) of 60% at 850nm and 40% at 940nm, which is three to five times better than sensors without this technology. This excellent QE enables the use of lower power IR illumination in total darkness, resulting in an estimated three times reduction in system-level power consumption.

The 940nm NIR lighting cannot be detected by human eyes in dark indoor settings, while the 850nm light is ideal for outdoor security cameras. The OS04A10’s ability to capture crisp, clear images using undetectable 940nm NIR light means indoor security cameras will not disturb sleeping occupants and can be easily concealed from intruders.

The amount of NIR light that a sensor requires to capture high quality images can be quantified with a new metric called NIR SNR1, which takes into account the QE, pixel size and read noise. The OS04A10 achieves industry leading SNR1850nm and SNR1940nm performance, which claims to be two to three times smaller when compared with the known available competitor sensors.

In other words, with the OS04A10, designers of security cameras that operate in total darkness can reduce IR illumination to consume two to four less power when compared with other sensors, for the same environment and over the same image detection range.

The OS04A10 achieves the industry’s lowest SNR1 while producing four megapixel and 1080p images for video recording. Additionally, OmniVision’s integrated dual-conversion-gain technology provides the industry’s best ULL and high dynamic range (HDR) performance, along with greater flexibility in selecting a companion image signal processor. The three-frame staggered shutter also minimises motion artifacts and enables an HDR of 120dB.

This image sensor is available in an extremely small package with a large 2.9 micron pixel size. This combination is enabled by OmniVision’s PureCel-S die stacking technology, which separates the imaging array and the processing function into two layers to enable additional features with a smaller die size. The PureCel-S technology also reduces power consumption. This results in smaller camera modules with greater design flexibility.

OS04A10 samples are available now and volume production is expected in Q3.