HP dv6500t: A "Minivan" Notebook

LCD Brightness, Contrast, and Viewing Angles

We recently did an article taking a closer look at the LCD panels on several laptops, and all of our future of laptop reviews will include coverage of this important feature. Our testing methodology is the same as we use in our desktop LCD reviews, although somewhat more limited in scope. The simple truth is that even the best laptop LCDs tend to pale in comparison to typical desktop LCDs. One of the reasons for this can be found by examining the panel used in the HP dv6500t notebook.

Using a utility called ASTRA32, we discovered that the LCD panel is an AU Optronics model AUO 2174 (though we admit that ASTRA32 could make mistakes). While that model number may not mean much to most people, perhaps more telling is the manufacture date of January 2005. This is a brand new notebook based on Intel's just-released Santa Rosa platform, and yet the LCD is apparently about 2.5 years old! Needless to say, LCD technology has advanced quite a bit in the past couple of years.

Our initial impression of the LCD panel prior to getting the above information was that it was pretty average at best. It's not particularly bright, viewing angles are limited (like most other TN panels), and colors seemed a bit off. All of these are characteristics that we would expect to find in LCDs from several years ago, but we ran through the rest of our tests regardless. Sadly, we would wager that HP isn't the only company using older LCDs on their laptops.

We'll start with a quick look at brightness and contrast ratios, then we'll look at viewing angles, and we'll conclude our examination of the LCD by looking at the color accuracy, before and after hardware calibration. For color accuracy, we are also including results using ColorEyes Display Pro in addition to Monaco Optix XR Pro. One of our readers pointed out that Monaco Optix XR Pro uses the older ICCv2 profile specification and that it might not be as accurate as software that uses the more recent ICCv4 specification. We still use the Monaco Optix XR Pro colorimeter (which is the same as the DTP-94) with both applications, and in general we did find that ColorEyes Display Pro produces better results on laptops. However, on at least a couple of displays we've tested, the results are better with Monaco Optix XR Pro, so we will continue to use both applications.




The white level is pretty typical of most laptop LCDs, maxing out at around 150 nits; black levels however are not very good, coming in at 0.66 nits -- the brightest "black" of any of the tested LCDs. The net result is one of the lowest contrast ratios we've measured. Subjectively, we would agree with the measurements: the overall quality of the LCD panel is slightly better than the panel on the ASUS A8Js, but we wouldn't rate it better than any of the other LCDs.

Brightness and contrast ratios aren't necessarily the most important aspect of a display, so let's move on to the other areas. Here's a look at the viewing angles, taken at 30° from center. Images for the other laptops can be viewed at the following links:

ASUS A8Js
ASUS G2P
Dell M1710
MSI S271


The lackluster LCD performance continues, with viewing angles that are no better -- and often worse -- than any of the other LCDs. During typical use of the notebook, it's not uncommon to find that you need to adjust the screen in order to properly see things. Even a small movement of your lap can mean the difference between an okay viewing angle and one that washes all of the colors out. Since all of these notebooks so far use TN panels, the somewhat limited viewing angles aren't too surprising. We are still trying to get some laptops in for testing that use IPS panels, as those are likely to perform better.