How it Works
1. Generate a white grid pattern with a video pattern generator. Place the gauge on the area where convergence is to be measured. If the horizontal lines of the grid pattern are not converged, they will appear as three separate blue, green, and red lines.
2. Rotate the knobs on each side of the gauge until the brightness center of the three images lines up. The image has now been optically reconverged.
3. The amount of convergence between blue/green and red/green can be read from the scales directly. The blue/red error can also be obtained. Click on Convergence Gauge in Quality Control for more information
Note: This example show a CM7AG, as the center prism is green.