PMOLED (Passive Matrix Organic Light Emitting Diodes) is an emerging organic material light emitting display technology, which has the characteristics of ultra-thin, high brightness, high contrast, low power consumption and so on. In many occasions, PMOLED is widely used in small size, low power consumption, high performance display devices, such as mobile phones, watches, wearable devices, etc. However, as PMOLED technology continues to develop, its resolution and color depth are seen as limiting factors, which we discuss in detail below.

 

1. Resolution limitation

The main reason for the resolution limitation of PMOLED is the limitation of its manufacturing process. In PMOLED, each independent pixel needs to be connected to a transparent electrode on the silicon substrate, and the size of this transparent electrode is the main factor restricting the resolution of PMOLED. At present, the resolution of PMOLED is generally between 72x40 and 480x128 pixels, and higher resolution requires more electrodes, which will increase the size of PMOLED chip and cause more cost and technical challenges.

In addition, the resolution limit of PMOLED is also affected by the transistor array. In a PMOLED screen, an array of transistors is used to control each pixel. However, due to the limitations of the array driver design, PMOLED is also facing difficulties in improving the resolution. At present, the design limitation of PMOLED in terms of transistor array generally limits the resolution within 128x128.

 

2. Color depth limitation

The color depth limitation of PMOLED mainly comes from the limitation of its light-emitting characteristics and light-emitting materials. In PMOLED, the type and combination of luminescent materials determine the color and brightness that the screen can display. Generally speaking, red, green, and blue monochromatic LEDs can form the three primary colors of RGB (red, green, and blue), and achieve colorful display effects through different brightness and color combinations. However, different combinations will produce different brightness and color depth.

Currently, the color depth of PMOLED is usually between 16-bit color and 24-bit color. 16-bit color can display 65,536 colors, while 24-bit color can display more than 16 million colors. In addition, the color depth of PMOLED is limited by the driver. Some PMOLED screens use low-power drivers, which can limit the depth and brightness of screen colors.

 

In general, the limitations of PMOLED's resolution and color depth are mainly due to its manufacturing process and material characteristics. With the continuous development of technology, PMOLED technology will gradually mature, and there may be PMOLED screens with higher resolution and deeper color depth in the future.