Auto-darkening of SUN screen?

[Michael Stumpf]

Does anyone have a program (a modified getty?) which darkens the screen of
a SUN workstation after some minutes of displaying "<host> login:"? We do
not want to switch on and off the screens several times a day and we also
do not want to stay them in the state described above for several hours.
After touching some key on the keyboard, the screen has to be "switched
on" of course.  Michael.

Dipl.-Math. Michael Stumpf
Psychological Institute
University of Freiburg
Niemensstr. 10
D-7800 Freiburg im Breisgau
West Germany