620 Appendix B Image Reference
Purpose The resolution of your monitor should meet or exceed the design specifications.
Method Adjust the brightness, contrast, and focus to their correct settings first. You should be able
to see individual and distinct pixels in each of the boxes. Failure to see distinct pixels may
indicate you have a defective video amplifier, focus correction circuit, or picture tube.
Note: If multi-colored areas appear on a mask-type color picture tube, you may have a
problem with convergence, or you may be exceeding the resolution of the picture tube.
CirclesLDescription Special test image developed per customer specifications. In the primary version (shown
below), the image consists of five large white circles on a black background. The circles
are positioned in the center and in the corners of the active video area. The secondary
version inverts the image to black circles on a white background.
Purpose This pattern is specified by some monitor manufacturers for checking and adjusting video
scan size, linearity, and over scanning.