Dynamic Range

What a difference high dynamic range can make

How complicated can a feature like high dynamic range be? Here we go: Dynamic range represents the ratio between the greatest amount of light to produce the brightest pixel and the least amount of light to produce the darkest pixel within the same frame. More simply, dynamic range is a CMOS feature that handles extreme variations of bright and dark conditions within the same scene, rapidly adjusting to the changes. It’s no different than the human eye, adjusting quickly to take in the whole scene.

But it does so much more. High dynamic range imagers with regional exposure weighting and regional gain setting can go even further in helping digital signal processors (DSPs) reproduce typically hard-to-distinguish details and provide enhanced imaging capabilities. This is especially critical in machine-vision applications such as automotive scene-understanding sensors and automated surveillance.

Our line of high dynamic range image sensors provides outstanding performance and proven reliability for automotive and surveillance systems that operate in extreme lighting conditions. In forward-looking automotive applications like lane-departure warning, adaptive headlight control, and adaptive cruise control, our imagers can clearly and accurately capture details in scenes that contain dramatic variations of light and shadows. Aptina imagers are providing the high dynamic range necessary to make new and potentially unique solutions possible.

What Aptina does well

We believe we’ve created some of the most flexible dynamic range sensors. And here’s how we did it: We extended the range of a sensor’s knee points, which added finer controls. The sensor then outputs superb images of scenes that contain both brightly and dimly lit areas, like what you’d encounter when exiting a tunnel on a bright, sunny day.

But we didn’t stop there. We combined this great functionality with other key features to create ideal image sensor solutions. Some of our solutions include TrueSNAP—a global shutter feature that captures fast-moving images without image tearing. Our context-switching feature enables two applications with separate imaging needs—like intelligent headlamps and lane departure warning—to be run from a single sensor, without processing loads and dropped frames.

What do high dynamic specs really mean?

At Aptina, we work hard to ensure that our testing measures are as accurate as possible. And measuring dynamic range isn’t easy because it isn’t standardized, so it’s not like we can compare the performance specs of competing parts from different manufacturers. That makes it hard to know whether the numbers you’re reading are real or just inflated marketing specsmanship.

But it gets trickier. Accurately measuring dynamic range is also complicated because it comes with additional options like companding. So, what do we do? We measure and re-measure past performance. And then we measure it again. We set our specs based on what we believe is the most accurate measurement. If we think a part can meet better dynamic range—or any performance measure for that matter—then we go back to the design. We don’t pad our specs with exaggerated claims.

Like many features, the surest way to judge quality is real-world performance, which is where Aptina excels. Even with solid specs, it requires extensive expertise to be able to fully utilize complex features. We pride ourselves on our ability to understand our customers’ applications; our field applications engineers can be invaluable guides in tuning systems to produce the best results.

View our high dynamic range videos on our automotive page to see for yourself what we’re saying here. We’re confident you’ll agree that our superior designs and expert support provide some of the most compelling imaging solutions in the market.