Standardized Calibration Sequences for Fine Pitch Optical Inspection Engines
Standardized optical calibration using certified glass targets and phase step standards ensures micron-level accuracy across fine pitch inspection runs.
Solder Volume Calculation
Volumetric Measurement
A mathematical integration computes the three dimensional quantity of solder paste deposited on a circuit board pad. Solder paste printers use solder volume calculation to verify that the printed deposit is sufficient to form a reliable solder joint during reflow. This inspection prevents defects like insufficient solder and solder bridging before components are placed.
It is the primary metric for tracking stencil printer performance on surface mount lines.
Process Control
Estimating the deposited paste volume involves measuring the height and area of the printed brick across multiple points on the pad. Solder volume calculation is performed by structured light scanners that project light fringes onto the board and measure the phase shift. The system multiplies the cross sectional area of the deposit by the measured height to find the total volume.
This value is compared to the theoretical aperture volume of the stencil to find the percentage volume. When the volume deviates from the target by more than thirty percent, the printer is stopped for a stencil wipe cycle. This automated feedback prevents the continuous printing of defective deposits.
Joint Quality
Insufficient paste volume is the leading cause of open circuits and weak solder joints after the reflow oven. If the volume is too high, it leads to solder balling and shorts between adjacent fine pitch component pads. Tracking this calculation across batches allows engineers to identify solder paste viscosity changes and stencil wear.
This proactive analysis maintains high yield rates during high volume double sided assembly runs.