Java Script Stücke als PHP Variable?

[Ajax]

Salute!

<?php ob_start();?>  
<script type='text/javascript'>document.write(screen.width)</script>  
<script type='text/javascript'>document.write(screen.height)</script>  
<script type='text/javascript'>document.write(navigator.javaEnabled());</script>  
<script type='text/javascript'>document.write(navigator.appName);</script>  
<script type='text/javascript'>document.write(navigator.appName);</script>  
<script type='text/javascript'>document.write(navigator.appVersion);</script>  
<script type='text/javascript'>document.write(navigator.cookieEnabled);</script>  
<script type='text/javascript'>document.write(navigator.language);</script>  
<script type='text/javascript'>document.write(navigator.platform);</script>  
<?php  
$der_ganze_text = ob_get_clean();  
//var_dump($der_ganze_text);  
file_put_contents("try.txt",$der_ganze_text);  
?>

Danke, aber irgentwie schreibt er mir so /\ auch:
<script type='text/javascript'>document.write(screen.width)</script>
statt: z.b. 1600

l.g.