What to do if thinkphp tcpdf is garbled?

composer require tecnickcom/tcpdf

https://tcpdf.org/examples/

<?php
namespace app\admin\logic;
use think\Db;
use TCPDF;
class Pdf extends \app\common\controller\Base
{
       public static function conrtact($data)
    {
        $sno = $data[&#39;sno&#39;];
        $kid_name = $data[&#39;c_name&#39;];
        $pdf = new TCPDF(PDF_PAGE_ORIENTATION, PDF_UNIT, PDF_PAGE_FORMAT, true, &#39;UTF-8&#39;, false);
        $pdf->SetCreator(PDF_CREATOR);
        $pdf->SetAuthor(&#39;Nicola Asuni&#39;);
        $pdf->SetTitle(&#39;TCPDF Example 001&#39;);
        $pdf->SetSubject(&#39;TCPDF Tutorial&#39;);
        $pdf->SetKeywords(&#39;TCPDF, PDF, example, test, guide&#39;);
// set default header data
$pdf->SetHeaderData(PDF_HEADER_LOGO, PDF_HEADER_LOGO_WIDTH, PDF_HEADER_TITLE.&#39; 001&#39;, PDF_HEADER_STRING, array(0,64,255), array(0,64,128));
$pdf->setFooterData(array(0,64,0), array(0,64,128));
// set header and footer fonts
$pdf->setHeaderFont(Array(PDF_FONT_NAME_MAIN, &#39;&#39;, PDF_FONT_SIZE_MAIN));
$pdf->setFooterFont(Array(PDF_FONT_NAME_DATA, &#39;&#39;, PDF_FONT_SIZE_DATA));
// set default monospaced font
$pdf->SetDefaultMonospacedFont(PDF_FONT_MONOSPACED);
// set margins
$pdf->SetMargins(PDF_MARGIN_LEFT, PDF_MARGIN_TOP, PDF_MARGIN_RIGHT);
$pdf->SetHeaderMargin(PDF_MARGIN_HEADER);
$pdf->SetFooterMargin(PDF_MARGIN_FOOTER);
// set auto page breaks
$pdf->SetAutoPageBreak(TRUE, PDF_MARGIN_BOTTOM);
// set image scale factor
$pdf->setImageScale(PDF_IMAGE_SCALE_RATIO);
// set some language-dependent strings (optional)
if (@file_exists(dirname(__FILE__).&#39;/lang/eng.php&#39;)) {
    require_once(dirname(__FILE__).&#39;/lang/eng.php&#39;);
    $pdf->setLanguageArray($l);
}
// ---------------------------------------------------------
// set default font subsetting mode
$pdf->setFontSubsetting(true);
// Set font
// dejavusans is a UTF-8 Unicode font, if you only need to
// print standard ASCII chars, you can use core fonts like
// helvetica or times to reduce file size.
$pdf->SetFont(&#39;dejavusans&#39;, &#39;&#39;, 14, &#39;&#39;, true);
// Add a page
// This method has several options, check the source code documentation for more information.
$pdf->AddPage();
// set text shadow effect
$pdf->setTextShadow(array(&#39;enabled&#39;=>true, &#39;depth_w&#39;=>0.2, &#39;depth_h&#39;=>0.2, &#39;color&#39;=>array(196,196,196), &#39;opacity&#39;=>1, &#39;blend_mode&#39;=>&#39;Normal&#39;));
// Set some content to print
$html = <<<EOD
<h1>Welcome to <a href="http://www.tcpdf.org" style="text-decoration:none;background-color:#CC0000;color:black;"> <span style="color:black;">$kid_name</span><span style="color:white;">PDF</span> </a>!</h1>
<i>This is the first example of TCPDF library.</i>
<p>This text is printed using the <i>writeHTMLCell()</i> method but you can also use: <i>Multicell(), writeHTML(), Write(), Cell() and Text()</i>.</p>
<p>Please check the source code documentation and other examples for further information.</p>
<p style="color:#CC0000;">TO IMPROVE AND EXPAND TCPDF I NEED YOUR SUPPORT, PLEASE <a href="http://sourceforge.net/donate/index.php?group_id=128076">MAKE A DONATION!</a></p>
EOD;
      // Print text using writeHTMLCell()
      $pdf->writeHTMLCell(0, 0, &#39;&#39;, &#39;&#39;, $html, 0, 1, 0, true, &#39;&#39;, true);
      // ---------------------------------------------------------
      // Close and output PDF document
      // This method has several options, check the source code documentation for more information.
      $pdf->Output(&#39;example_001.pdf&#39;, &#39;F&#39;);
      return  &#39;example_001.pdf&#39;;
    }
}

 <object :data="example_001.pdf" type="application/pdf" style="width:100%;height:1200px;"></object>