Hi,
If you want to open a PDF in a new browser window from a PDF viewed in a browser window, you need a little help using JavaScript.
Create a button field or link and in the Action tab, select Run a JavaScript from the Select Action pull-down menu. Click the Add button to open the JavaScript Editor and type the following code in the Editor window:
app.launchURL("http://www.mycompany.com/pdfDocument.pdf", true);
In the above code, replace www.mycompany.com with your URL. Replace pdfDocument.pdf with the name of the PDF you want to open. The "true" statement triggers opening the PDF in a new browser window.
;-)