Here's some very simple pure JavaScript (no HTML, no jQuery) that converts an object to JSON and submits it to another page:

/*
    submit JSON as 'post' to a new page
    Parameters:
    path        (URL)   path to the new page
    data        (obj)   object to be converted to JSON and passed
    postName    (str)   name of the POST parameter to send the JSON
*/
function submitJSON( path, data, postName ) {
    // convert data to JSON
    var dataJSON = JSON.stringify(data);

    // create the form
    var form = document.createElement('form');
    form.setAttribute('method', 'post');
    form.setAttribute('action', path);

    // create hidden input containing JSON and add to form
    var hiddenField = document.createElement("input");
    hiddenField.setAttribute("type", "hidden");
    hiddenField.setAttribute("name", postName);
    hiddenField.setAttribute("value", dataJSON);
    form.appendChild(hiddenField);

    // add form to body and submit
    document.body.appendChild(form);
    form.submit();
}

Use some PHP like this on the target page to get the JSON:

$postVarsJSON = $_POST['myPostName'];
$postVars = json_decode( $postVarsJSON );

Or, more simply for JavaScript:

var postVars = JSON.parse( <?php $_POST['myPostName']; ?> );

You could use HTML5 local storage for this:

https://developer.mozilla.org/en/DOM/Storage

Most modern browsers including IE7+ support it.

If you want to change the phyiscal page in the browser, then you have to get the browser to do it. You can have an AJAX in the background, but it's not going to affect the browser page.

The simpliest way to get the browser to change the page is to set the window.location property to the url of the new page. Note, however, you can only do a GET this way.

I'd suggest doing an AJAX POST, and have that return a URL which you can have the borowser get to display the page you want.

I see there are several ways to do this:

1. Cookies. Write values to cookies and read it in the opened window.
2. Pass as a part of url hash: window.open(url + '#' + encodeURIComponent(JSON.stringify(json));

3. I would try to

   winRef = window.open(...);

   winRef.postMessage(...);

https://developer.mozilla.org/en/DOM/window.postMessage

I didn't try the third option, but it might be a nice alternative to 1 and 2.