How Active Sensor Control Provides Reliable Pixel Data for Metrology Cameras

The benefits of greater accuracy and throughput from high-resolution cameras can only be realized if the entire image sensor is usable.  Metrology cameras are optimized for uniformity and dynamic range among other parameters to provide the most accurate starting image.  Metrology cameras are relied on when the pixel information is used as measurement input such as with process control systems for semiconductor and electronics manufacturing and others.   

Active Sensor Control (ASC) is Adimec’s toolbox for our metrology cameras to achieve the most usable pixels and accurate data.  It incorporates all of the functions used to tune the sensor for the specific needs of an application and measures to optimise imaging performance under the system conditions.  There are three steps involved to ensure you get accurate input information from the camera for your measurement method.

Step 1:  Sensor Technology is characterized for optimized design and implementation

• We gain full understanding of the image sensor, variations between sensors, and performance under different conditions.
• We characterize each individual image sensor and apply sensor settings specific to its operating conditions.

Step 2:  Sensor operation is tuned during production to minimize blemish generation, increasing the operational imaging range (DNR, uniformity)

• We measure specific critical artifacts understood to be present in the camera + sensor combination.
• Then, we test the sensors beyond the manufacturers’ specifications to guarantee consistency.

Step 3:  Calibrate each camera to effectively manage remaining blemishes and non-uniformity responses through embedded corrections

• The parameters that are optimized are specific to the image sensor and the customer’s measurement method.
• Embedded functions are included to allow for calibration to be done automatically in the field to adjust to system conditions.

By minimizing the blemishes per individual camera we make sure the largest performance range results, and less severe corrections need to be done that can reduce the contrast range (DNR). All of the tunings involved are to guarantee the cameras consistently provide reliable image quality for accurate measurements.

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Industrial metrology cameras for increased performance of process control systems