In 2019, the company BOE showed new screens with a high contrast ratio of 150,000:1. However, it is very difficult to find a description of this technology, there is almost no information about them on the web. From the official release, we can understand that these are good displays with very good tech specs.
According to the official press release:
BD Cell is a display technology introduced by BOE, which can greatly improve the contrast ratio of display and marks a new breakthrough in the TFT-LCD technology. BOE innovatively designs two layers of black-and-white and color cells for the display and uses pixel division technology and micron-level dimming technology to control the images more finely so that the display can have an ultra-high contrast ratio of up to million-level and show the most natural colors. In addition, that display technology has obvious advantages in the black field and grayscale. BD Cell display has a black field brightness of fewer than 0.003 nits and can realize 12 bits color depth. Its low grayscale transition is more natural, and every color and detail of the images can be clearly represented. This innovative technology can make users feel a better and mind-blowing UHD experience. It is said that BOE’s BD Cell technology can be used in medium- and large-sized displays such as those for TVs, notebooks, and monitors. More devices featuring the BD Cell technology are yet to be put on the market.
However, our goal is to explain BD Cell displays advantages and disadvantages in simple words.
BD Cell display technology explained
BD Cell display, it is an IPS ADS display technology. BD Cell is the next generation of IPS displays which BOE develops.
BD Cell displays are displays which use two layers of pixels. The structure of these displays is shown in the picture below.
In such displays, the backlight is located behind the screen. Then there is a layer of black pixels and then there is a third layer with an RGB matrix.
How BD Cell display works
In fact, the second black and white layer serves the function of backlight control, to improve image quality. As you know, the main disadvantage of IPS displays is the lack of saturated black color, even when a black picture should be displayed, the light penetrates through the pixels and makes the screen gray. Thus, the picture looks unsaturated and not natural.
The second layer also overlaps the light flux and the image becomes more realistic in black tones. And because the pixels of both layers overlap, it allows you to control the backlight at the pixel level. With the ability to control the backlighting of each pixel, you can turn off the backlight very selectively. And this in turn reduces the halo around bright objects and increases the contrast of the image, which makes the image more realistic.
It’s also possible to fully enable all the pixels in an RGB layer, and control the image using only the second layer of black pixels, this allows you to create a black and white image with more colors. According to BOE, BD CELL displays have a grayscale depth of 12 bits. When displaying a color image, the color depth is 10 bits.
BOE is positioning its BD Cell displays as a competitor to OLED displays. Time will tell whether this is true or not, given that BD Cell displays only began to be mass-produced in 2020 and this is only the first generation.