Blurring icons in Visualization

[aicanx]

Hi everybody, 
I have a Modbus address with data type "07. 2 byte unsigned integer" to control the fan speed.
With value 1 the fan speed is at: low
With value 3 the fan speed is at: medium
With value 5 the fan speed is at: high
Do you have any idea how to highlight the icon when I select 1 control value and the other 2 icons will be blurred?
Thanks!