The text has been deformed, like a mosaic

[YountMan]

When I draw the barcode, the text becomes a mosaic.

code show as below

	    var canvas = document.createElement("canvas");
	    JsBarcode(canvas, md5Key, {
	            format: "CODE128",
	            height:100,
	            fontSize:10,
	            margin:1,
	            fontOptions:'italic',
	            font:'Microsoft YaHei',
	            
	            displayValue:true,
	            text:tipName + '：' + tip,
	            textAlign:'left',
	            textPosition:'buttom',
        });
	    var base64 = canvas.toDataURL("image/png");

I found this library when I googled polyfill I hope the author can join this or similar processing mechanism， When I print out using a thermal printer, the text cannot be read.