Megapixel automotive image sensors with LED flicker mitigation

The optimal clarity and range offered by this platform, in combination with integrated ASIL-C features, is vital for front-view automotive applications, such as ADAS and level 3+ autonomous vehicles, where the ability to accurately detect people and objects from far away in all lighting conditions is safety-critical.

Cases where the scene has very dark and very bright areas, e.g., exiting a tunnel with the sun low on the horizon, inspired OmniVision to develop these state-of-the-art HDR sensors. In addition, LEDs are becoming omnipresent on the road, including illumination, traffic lights, road signs and bus displays. Having a sensor with an LFM solution is a must for automotive applications to extract all the necessary information in front of a vehicle.

“Yole Développement’s recent technology and market research ‘Imaging for Automotive 2019’ confirms the accelerated market pull for viewing and ADAS applications at a 13.7% CAGR between 2018 and 2024,” said Pierre Cambou, principal analyst at Yole. “OmniVision’s new automotive CIS platform includes key features such as HDR and LFM, and is enabled by a stacked semiconductor approach. Introducing such exciting technology to its automotive lineup allows for on-chip integration that reduces BOM costs while providing a high level of performance and features in a very compact package, indeed much in sync with current market expectations.”

Celine Baron, Staff Automotive Product Marketing Manager at OmniVision, added: “These new image sensors utilize OmniVision’s dual conversion gain (DCG) technology to achieve 82dB dynamic range on the first exposure, whereas competitors’ image sensors only provide a dynamic range of 60dB or less. Unlike DCG, the competing method, known as staggered HDR, relies on additional passes that introduce motion artifacts and diminish range, especially in low light.

“Additionally, OmniVision’s 3D stacking technology allowed us to integrate our unique HALE algorithm into the OX08B. The result is that this sensor platform provides an industry-leading 140dB HDR, along with the best LFM performance and high 8MP resolution for superior front-view captures, regardless of external lighting conditions.”

With its four-cell technology, OmniVision can offer the industry’s best LFM with optimal low-light performance in a 1/1.8” optical format that has a 2.1 micron pixel pitch. Furthermore, OmniVision’s PureCel Plus-S stacked architecture enables each pixel to perform optimally via higher full-well capacity for improved HDR.

This platform also enables sensor fusion, where the same camera signal is used for ADAS and autonomous machine vision while simultaneously feeding into ‘dash cam’ front-view recording and display systems. Additionally, these sensors have region-of-interest functionality for even clearer images of moving objects within fixed areas in the camera’s field of view. To ensure the safety of images being used for machine vision applications, ultra low power cyber security is also integrated using industry-standard encryption techniques and consuming less than ten percent of the sensor’s total power budget.

Both sensors in this platform offer 4-capture, 3840x2160 resolution at 36fps and a 16:9 display aspect ratio. They will be available in different color-filter patterns to match the leading machine vision applications in the industry. For instance, an RCCB color filter will be offered to allow in more light and further improve performance in dark environments.

The OX08A and OX08B image sensors are both planned to be AEC-Q100 Grade 2 certified.