Rather than a normal submit button (<input type="submit" ...>), you can use the image input type (<input type="image" ...>). The image input type specifies a graphical submit button that functions like a server-side image map.
Unlike normal submit buttons (which return a name=value pair), the image input type returns the x-y coordinates of the location where the user clicked on the image. The browser returns the x-y coordinates as name.x=000 and name.y=000 pairs.
For compatability with various non-graphical browsing environments, the VALUE and ALT attributes should be set to the same value as the NAME attribute. For example:
<input type="image" name="Send" alt="Send" value="Send" src="send-button.gif">