automatic door?

I have a very simple door opening script, how do I make it so that when someone is within 1m it automatically opens???

default
{
touch_start(integer total_number)
{
rotation rot = llGetLocalRot();

if (rot.z == 0)
{
rot.z = -0.707107;
rot.s = 0.707107;
}
else
{
rot.z = 0;
rot.s = 1;
}

llSetLocalRot(rot);

}
}

you could use a sensor or another prim to provide a collision or just do the collision on the door itself

/54/b7/240415/1.html

You could make it phantom. Looks the same, but you just walk through it.