Automated Machine Vision Calibration Strategies for Variable Chemical Substrates
Automated vision calibration for variable chemical substrates requires real-time dual-wavelength exposure and motorized solvent-resistant target profiles.
TDI CMOS Line Scan
Meaning
Advanced sensing technologies that accumulate charges over multiple rows of pixels during an exposure cycle allow for high speed imaging in low light conditions. A tdi cmos line scan sensor functions by synchronizing the movement of the object with the internal transfer of charges across the pixel array. This method increases the exposure time for a single point on the object without reducing the scanning speed.
It is used in applications such as flat panel display inspection and semiconductor wafer processing where high sensitivity is required.
Integration Stage
Integration count per pixel defines the sensitivity gain of the system. Standard sensors may offer up to two hundred and fifty six stages of integration. This multiplication of the signal allows the system to operate with much lower light levels than a traditional single line camera.
Signal Ratio
By summing the charge across multiple stages, the sensor improves the signal to noise ratio significantly. Random noise from the electronics is averaged out while the coherent light signal from the object is amplified. This results in a cleaner image with better contrast for automated defect detection.
Clock Synchronization
Precise timing between the sensor and the movement of the object is mandatory for image quality. If the timing is off, the image will appear blurred or distorted because the charges do not align with the physical features. This requires a precise encoder signal to drive the camera timing.