How To Make A Gun Scope Zoom In

Hello,

I Have my basic gun scope script:

 var posNotAiming : Vector3 = Vector3(-69.07644, -16.59074, -27.22817);
 var posAiming : Vector3 = Vector3(0, 1, 0);
 var aimRacio : float = 0.4;
 var cameraObject : GameObject;
 
 function Update()
 {
     if(Input.GetButton("Fire2")){
        cameraObject.GetComponent(FPSMouseLook).currentAimRacio = aimRacio;
         transform.localPosition = Vector3.Lerp(transform.localPosition, posNotAiming, 0.1f);}
     else{
        cameraObject.GetComponent(FPSMouseLook).currentAimRacio = 1;
         transform.localPosition = Vector3.Lerp(transform.localPosition, posAiming, 0.1f);} 
 }

I Want the scope not just to come to the centre of the screen but also zoom in a little. If you know how I Can edit the script, leave a comment below! Thanks in advance!