| Screen: To place the Screen, click at the point above the central axis where you want the top of the object to appear. The new screen is centered on the central axis. When the Select button is pressed, you can move and resize the screen. An alternative view of this object is available. When you place a screen, a window opens that shows the image currently appearing on the screen. This window is called the Screen View. Below the picture of the screen image, the Screen View window gives you several options: Preview Resolution: Determines the resolution of the image when online rendering is enabled (see below). Preview resolution has three values: low, normal, and high. As the resolution increases, the time needed to compute the image also rises. Brightness Scale has two values: threshold and relative. A threshold scale indicates that, for an image to form, light intensity must be above a threshold value. A relative scale indicates that image brightness is determined relative to the intensity of light hitting the screen. Enable online rendering: If this box is checked, the computer will calculate a new screen image every time you change the setup in the simulation window. Render: Updates the screen image. The computer renders an image with the best possible resolution (better than high). Copy to Clipboard: Copies the view image to the CPU Java Clipboard. Use the Paste tool to copy the image to the simulation window or into another CPU Java application. Close: Closes the screen view window. If you close the Screen View window, you can always reopen it. Click on the Select button and select the Screen. A small eye will appear at the lower left corner of the Screen. Clicking on this eye will reopen the Screen View window. In the screen's Properties Box, you can make the screen transparent (so it won't block the mirror) and force the screen to ignore the original light source (so that only the reflected image appears on the screen).