ADDITIONAL SYSTEM INFORMATION :
WIN10, JDK12

A DESCRIPTION OF THE PROBLEM :
I created some lines and put on the anchor pane, the horizontal lines, the vertical lines and some left slash lines, right slash lines(45 degrees angle), it is very strange that horizontal/vertical lines shows darker color than the slash lines, they all have same color stroke and width 1. When I display these lines on the giant LED display screens where you can see clearly on each pixel, it shows another problem, the lines shown on the LED screen not pixel to pixel, the lines look like "tow lines LEDs" lighted up as one line, it should be one line of pixels lighted up only.
I can not figure out this. Not sure what's going on. Any help is much appreciated.

I want to send pictures, but seems no place to send?