I by "pop-up" your mean creation of a new browser window or a tab, I would like to warn you against it. In addition to certain difficulties you may have, pop-ups can be blocked in browser by many users who don't like it, by some good reasons.
It would be much better to develop modal-like behavior inside a Web page, and do it fully locally, with JavaScript. The first solution would be this:
https://jqueryui.com/dialog[
^].
Also, there are many 3rd-party jQuery plug-ins, collectively known as "modal popup", with different effects, such as transitions, and, notably, dimming of the rest of the page. Please see:
http://bfy.tw/AJH[
^].
If you need to learn jQuery (highly recommended), please see:
http://en.wikipedia.org/wiki/JQuery,
http://jquery.com,
http://learn.jquery.com,
http://learn.jquery.com/using-jquery-core,
http://learn.jquery.com/about-jquery/how-jquery-works (start from here).
—SA