27. Display Quality: Static Images

First with brightness set at maximum (toward pure white) we measure the brightness of 64 white rectangles in an 8 x 8 matrix across the display. Next we set brightness at minimum (toward pure black) and measure the brightness of the same 64 rectangles. Measurements are made with a luminance meter that provides values in candelas per square meter (cd/ m2).

For each display we present two charts, one for brightness and one for contrast. Brightness measures in each rectangle are used directly. Contrast measurements are derived by dividing a rectangle's brightness value by its contrast value. Relating values among neighboring fields and high value lines emerge from linear interpolation of measurements in adjacent boxes. The various colors indicate parts of the display surface for which measured values occur within specific value ranges, as indicated in the legend. Colors shown have nothing to do with actual pixel colors on the monitor.

The upper edge of the diagram symbolizes the lower horizontal edge of the display. The opposite edge thus corresponds to its upper edge. The other two edges represent the left and right sides of the display, respectively.

In addition to creating the display charts, we compute mean brightness and mean contrast across the 64 rectangles. Mean brightness is frequently used to indicate a display's brightness. Mean contrast is often presented as a display's "contrast ratio."

Here are the display charts. In the next section we'll discuss the charts and what they have to say about our four gaming notebook candidates.