pixel in unit in unity3d and have a full screen texture

this was my code after a long research ,but unity released a new version…!

var NewObjectWidth : float ;
var OldObjectWidth : float ;
var NewObjectHeight : float ;
var OldObjectHeight : float ;
function Start ()
{
	OldObjectWidth = this.transform.localScale.x ;
	OldObjectHeight = this.transform.localScale.y ;
	//NewObjectWidth = (OldObjectWidth /1366) * Screen.width ;
	//NewObjectHeight = (OldObjectHeight/768) *  Screen.height ;
	//print (OldObjectWidth);
	NewObjectWidth = OldObjectWidth * 768 / 1368 * Screen.width / Screen.height;
	this.transform.localScale.x = NewObjectWidth ;
	//this.transform.localScale.y = NewObjectHeight ;	
	//print (NewObjectWidth);
}
function Update ()
{
	
}

and this was the camera code

var ScreenHeight: int ;
var SW : int ;


 
function Start ()
{
SW = Screen.width ;
ScreenHeight = Screen.height ;
camera.orthographicSize = ScreenHeight/2 ;
}

function Update ()
{
	
}

but now everything is changed i want my background fill the screen and then other objects …
would anyone please help me im so confused now the scale depends on pixel to unit parameter , so how can change the camera…

oah my god , i dont beleave but it seems that i found the answer here