time out between 2 touches android

I’m working on an android game and I got a simple code for touching a button with a tag.
But when you touch the button it loads a new scene wich has another button on the exact same spot and when I try it out on my phone when I touch the first button the game loads the new scene and immediately touches the second button to so i can’t touch the first button without touching the second one. I would like to have a delay that you can’t touch anything for 1 second or so.
Here is my code:` #pragma strict
var knop : GameObject;
var knopingedrukt : GameObject;

function Start () {
knop.renderer.enabled = true;
knopingedrukt.renderer.enabled = false;
}

function Update ()
 {
   if (Input.touchCount > 0)
   {
       var ray = Camera.main.ScreenPointToRay (Input.GetTouch(0).position);
       var hit : RaycastHit;
    if (Physics.Raycast (ray, hit)) 
   {
    if(hit.collider.tag == "knop")
    {
    knop.renderer.enabled = false;
    knopingedrukt.renderer.enabled = true;
    Application.LoadLevel ("Classic");
    } 
   }
  }
 }`

In the Start or Awake function set a float to equal Time.time + 1. When you check if the hit actually hits the button also check that Time.time is greater than the float.

var ButtonEnableTime : float = 0;

// Then in start
ButtonEnableTime = Time.time;

// Then in your check
if (hit.collider.tag == "knop" && Time.time > ButtonEnableTime)

Sorry for typos, on my phone.