Blink is a feature to display colors of the objects in blinking on the display unit. For 3-Speed Blink, you can select from 3 blink speeds (Slow, Medium and Fast).
[Fast] blinks at twice the speed of [Medium]. [Slow] blinks at half the speed of [Medium]. If you select [None], the object will not blink.
There are cases where you can and cannot set Blink, depending on the [Color] setting available from the [System Settings] window's [Display Unit], in the [Display] tab.
1.6 Supported Colors
For information about Faded Color Blink, refer to the following.
5.4.2.2 Display Unit [Display] - Display Settings