LCD / backlight illumination test

[xfn]

Have any T43 owners checked the backgournd lighting of the LCD display:

1. Boot up the system in a dark room
(e.g. lights off, window shutters & doors of the room closed)

2. Display an all-black picture in full-screen mode
(You can just create the picture using wondows Paint or other graphic editors, and give it the same resolution of your screen's, e.g., 1400*1050 pixels)

3. Display an all-white picture in full-screen mode

Observe whether the LCD screen has even or uneven illumination during step 2 and 3.


My current result is:
Uneven lighting can be seen (in step 2) on the screen (some near the bezel, and some in the middle, already done some thing to the LCD frame?). Some people called it backlight "leak", "wash" or "spill" ...

If just very slightly twist the LCD frame, you can see the change of the background lighting (I'd read a post in which someone is trying to define an official way opening his thinkpad with his two hands on the top cover ). This is caused by the change of view angle.

Note that this phenomenon should not be seen in normal conditions (e.g., in a normally lightened environment). A perfect LCD assembly may also offer even lighting even in step 2, I guess.

[dr_st]

Side note: you can use "Dead Pixel Buddy" to display fullscreen black and white pictures.

[xfn]

Thanks for "Dead Pixel Buddy"

Any buddy knows why backlights "leak", "wash" or "spill" ... and how to reduce it I am new in the light distrubution of LCDs, just know that they have inverter, CCFL tube, reflector...