Hello  friend,
This is Helen from Bizbee, how are you?

Smartphone displays now are tested in RGB color mode. R is RED,G is GREEN, and B is BLUE. In the RGB model image, each RGB pixel component is assigned an intensity value which is in the range of 0-255.
By using only three colors, RGB image makes them composed in different proportions, showing 16777216 colors on the screen .
Different LCD determines the mixing ratio of display color Many LCDs on the market are either blue or red, or white this is determined by the combination of backlight, LCD and polarizer. Same materials produced in different batches may also have inconsistent hue issues.


K Numerical Value Standard: The display shows differently when K value varies:
1 Absolutely white at 6500-7500
2 cool color>7500
3 warm color<6500
As shown in the graph below. 
When K value is between 7500-8000, the display shows cool white, and the color is evenly cistributed. If the backlight brightness is sufficient, the LCD color will be very close to the original LG one.
 If between 6000-6500, it shows warm white, color is evenly distributed. If the backlight brightness is suficient, the LCD color will be very close to the original Sharp one.
The LCD color looks nice when K value is between 6000-8000, it will be starting to get blue when higher than 8000, and get yellow when lower than 6000.
Therefore, the perfect range is 6000-8000.


K Numerical Value PK:
At present, many suppliers and factories just use the naked eyes to detect the quality of color& brightness.

Bizbee tests each screen based on the K value & CD value. We regard it as qualified when it is within the range specified by our company, otherwise, it belongs to inferior-quality product.


K Numerical Value Form: Our screen is divided into High Spec. and aftermarket Quality.

1、 High spec. is TM/AUO LCD,    ESR highlight backlight, Original backlight LED, Original polarizer, Real 3D module,  AAA level.

2、 After market is TM/AUO LCD, Ordinary backlight, OEM backlight LED, OEM polarizer, AAA level,


Conclusion 
The reason why your suppliers are unstable on quality is that because their test standard is not digitized. but visually observed. The standard of each tester is different, which will resulit in different color& brightness, Bizbee uses data-based standard to detect products to guarantee the quality of your orders.

So what quality would you prefer ?  Aftermarket quality or our High spec.? welcome to comments or try our products.

BIZBEE TRADING LIMITED
Web: http://www.bizbee.com/100077WO.html
Tel: +(86) 755 2376 3769
Mobile/ Whatsapp: +(86) 13714565389
Skype: 
helen.xu0317
E-mail: helen.xu@ettrends.com / helen.xu@bizbee.com    
Add: Xinghe World, Wuhe Blvd South, Longgang District, Shenzhen, China