What is the cf key on an ultrasound machine

Is the question "What is the cfm key on an ultrasound machine"? The color function is activated or deactivated. The cfm key on an ultrasound machine is used to activate or deactivate the color function, as you can see from the instructions. Color ultrasound machine full name color Doppler ultrasound diagnostic instrument, is a collection of acoustic materials, information detection, electronic technology, micro-computer technology, image processing, precision technology and other multidisciplinary advanced technology in one of the medical equipment.