首先，您需要发出一个设置头文件的ajax请求。然后，您需要使用一些HTML5
API将接收到的二进制数据转换为base64。最后，使用data:协议和base64数据设置映像src 。

var oReq = new XMLHttpRequest();
oReq.open("GET", "yourpage.jsp", true);
oReq.setRequestHeader("Your-Header-Here", "Value");
// use multiple setRequestHeader calls to set multiple values
oReq.responseType = "arraybuffer";
oReq.onload = function (oEvent) {
  var arrayBuffer = oReq.response; // Note: not oReq.responseText
  if (arrayBuffer) {
    var u8 = new Uint8Array(arrayBuffer);
    var b64encoded = btoa(String.fromCharCode.apply(null, u8));
    var mimetype="image/png"; // or whatever your image mime type is
    document.getElementById("yourimageidhere").src="data:"+mimetype+";base64,"+b64encoded;
  }
};
oReq.send(null);

资料来源：

https://developer.mozilla.org/zh-
CN/docs/Web/API/XMLHttpRequest/Sending_and_Receiving_Binary_Data