TCPDF send to browser

Hi , i have a problem with TCPDF
Iwant send my code to browser ( from controller's method) with :
$pdf->Output($link_pdf, 'I');
but the result is strange characters :
https://postimg.cc/0zzfS4dt
I think i must set output to browser as pdf , how i can do ?

Does $link_pdf have a pdf extension?

i'm not a profi but this works for me so it might help

PHP Code:

class TPdfCustom extends Tcpdf
{
   -- lots of other stuff begin
   -- lots of other stuff end  

   private function pdfFilename(string $filename):string{
        $file = WRITEPATH.'cache/'.$filename;
        $ext=pathinfo($filename, PATHINFO_EXTENSION);
        if($ext=='') $file.='.pdf';
        return $file;
    }

    /**
     * @param $response
     * @param string $filename
     * @return void
     */
    public function sendToBrowser($response, string $filename):void{
        $file = $this->pdfFilename($filename);
        // save to file and then read the file
        $this->Output($file, 'F');
        $response->setHeader('Content-Type', 'application/pdf');
        $response->setHeader('Content-Disposition', 'inline; filename="' . $filename . '"');
        $response->setHeader('Content-Transfer-Encoding', 'binary');
        $response->setHeader('Content-Length: '. filesize($file),'');
        $response->setHeader('Accept-Ranges:', 'bytes');
        readfile($file);
        unlink($file);
    }
} 


i'm not a profi but this works for me so it might help

PHP Code:

class TPdfCustom extends Tcpdf
{
  -- lots of other stuff begin
  -- lots of other stuff end  

  private function pdfFilename(string $filename):string{
        $file = WRITEPATH.'cache/'.$filename;
        $ext=pathinfo($filename, PATHINFO_EXTENSION);
        if($ext=='') $file.='.pdf';
        return $file;
    }

    /**
    * @param $response
    * @param string $filename
    * @return void
    */
    public function sendToBrowser($response, string $filename):void{
        $file = $this->pdfFilename($filename);
        // save to file and then read the file
        $this->Output($file, 'F');
        $response->setHeader('Content-Type', 'application/pdf');
        $response->setHeader('Content-Disposition', 'inline; filename="' . $filename . '"');
        $response->setHeader('Content-Transfer-Encoding', 'binary');
        $response->setHeader('Content-Length: '. filesize($file),'');
        $response->setHeader('Accept-Ranges:', 'bytes');
        readfile($file);
        unlink($file);
    }
} 


Thank you work for me