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The all-aluminum MacBook features an LED-backlit display. The use of LED backlighting allows Apple to offer slightly improved battery life and color, while also eliminating the use of mercury.
High-end professional monitors and TVs use red, green, and blue LEDs instead of a fluorescent bulb to extend the gamut (color range) of the display. You’ll see this marketed in TVs and monitors with Sony TRILUMINOS, HP DreamColor, or NEC Spectraview-LED technology. These displays allow you to see “greener greens” and “redder reds” and reproduce more of the colors that exist in real-life. A handful of notebooks such as the new 17” MacBook Pro and Dell XPS Studio 16 use RGB LED displays, but the majority of shipping notebooks with LED backlit technology use an array of white LEDs.
Unlike the RGB technology that generates white light by combining red, blue, and green light, white LEDs are blue LEDs with yellow filters. While most LED backlit notebooks offer better color than equivalently spec’d notebooks, the main advantage to these types of screens are improved battery life, thinner screens, and more ecologically sound design.
The backlight is only one component to the ultimate picture quality. The LCD panel itself also plays a significant role. While the MacBook’s display isn’t comparable to the premium TN-film display on the MacBook Pro or the H-IPS panels of the 24” iMac or 24” Cinema Display, the MacBook still offers adequate quality for most users. We were fortunate to have two MacBooks with display manufactured by different companies. The AUO screen (9C8C) is considered to be superior to the LG-Philips (9C89) panel by most users. The differences are subtle, but the measurements agree.
Our MacBook with the AUO display had a peak brightness of 255 cd/m2 with a black level of 1.31 cd/m2. This results in a contrast ratio just shy of 195:1. Our sample with the LG-Philips display had a peak brightness of 254 cd/m2 but a black level of 1.41 cd/m2 resulting in a contrast ratio of 180:1.
While these ~200:1 contrast ratios sound like a catastrophically horrible results in a world of 1000:1 desktop displays, it’s worth putting things into context. 1 cd/m2 is equivalent to the amount of light 15 minutes after sunset. 0.1 cd/m2 is equivalent to the amount of light 30 minutes after sunset. The differences are subtle between the two units unless comparing side by side. Notebooks such as the Lenovo ThinkPad X300 or SL300 might only get 150:1 contrast, whereas the Dell XPS M1330 hits 550:1 and the Dell Studio 15 hits 800:1 contrast ratios. The previous generation MacBook Pro broke 1000:1 contrast and the current model has been measured in the 900:1 range.
More important than the contrast ratio is the color accuracy of the screen (all of the colors in between pure black and pure white). Using a digital Munsell ColorChecker 24 patch chart and a DTP-94 colorimeter, the AUO screen had very good color accuracy after calibration with a residual average delta E of 2.66 (peak 6.83). Grayscale accuracy ranged from 0.69 to 2.95 (Average 1.682). The LG-Philips display was worse overall with an average delta E of 3.19 (peak 8.03) but the grayscale accuracy was better than the AUO with a range of 0.91 to 1.78 and an average deltaE of 1.376.
These calibrated numbers are respectable for a notebook display. An 8-bit Samsung PVA desktop display capable of attaining 993:1 measured contrast ratio had an average delta E of 2.52 (peak 5.10) with a grayscale accuracy ranging from 0.49 to 3.03 (average of 1.312).
By convention, a delta E < 1.0 suggests that a highly trained observer, under ideal conditions will be unable to detect a difference. A delta E < 2.0 is a difference that is only noticeable with direct A/B comparison by an average observer. A delta E between 3 and 6 is “acceptable” match for commercial reproduction on printing presses.
MacBook (Sample 1)
LG Philips LP133WX2
Delta E: 3.19
MacBook (Sample 2)
AU Optronics B133EW02 V0
Delta E: 2.66
24“ LED Cinema Display
LG Philips LM240WU6
Delta E: 1.76
Using http://www.drycreekphoto.com/Learn/Calibration/monitor_black.htm it’s possible to see the gray square at Step 2 once calibrated. The factory default setting won’t allow you to see anything until Step 5. In summary, a calibrated MacBook display has adequate picture quality for working with basic photos or movies. Like other 13” TN display monitors, viewing angles are limited with a small sweet spot, and 6-bit color prevents the same quality of color that can be reproduced with a desktop display. Out of the box, color accuracy is considerably worse.