The focusing screen is a flat with glossy and matte translucent plastic, in which bring a split circle in middle.
Made of high quality optical PMMA to ensure its brightness,Ultra-bright
When the image is correctly focused, the circle becomes full and the line between will be unbroken. Otherwise, the line will separate the circle into two halves.
Pls Note: There is no need ground glass. The flat side of the split image screen is the upper surface, and the position of the upper surface remains unchanged. The side with sharp corners towards reflector.