If you are using Internet Explorer: after clicking on the image, a new screen will appear with a smaller image; however, when you put your cursor over this image, a square icon will appear with arrows at the four corners and, when you hover over this icon, it will say "Expand to regular size"; click on the icon and the bigger image will display.
If you are using Mozilla Firefox: after clicking on the image, a new screen will appear with a smaller image; however, when you put your cursor over this image, you will see a magnifying glass with a plus sign on it; click on the magnifying glass and the bigger image will display.