Techniques for distinguishing OLED and CSTN color screens

In view of this, this article mainly introduces the skills of distinguishing OLED and CSTN color screens, hoping to help everyone clearly distinguish and then choose the product they like. Let's start with the concept and principle of OLED and CSTN, and finally give the skills of distinguishing OLED and CSTN.

1. Concept

OLED, or organic light-emitting diode, is also known as organic electric laser display. OLED has the characteristics of self-luminescence, using a very thin organic material coating and a glass substrate. When current passes through, the organic material will emit light. In addition, the OLED display screen has a large viewing angle, can be flexible, and can significantly save electricity.

CSTN is actually a FSTN screen with a color film. Three pixels of RGB are used to form a display pixel. On the surface, it only increases the twist angle of the liquid crystal molecules, but in fact it is far from that, because the increased twist angle makes another characteristic of the liquid crystal appear, which is the birefringence mentioned above.

2. The principles of OLED and CSTN

The principle of OLED is that under the drive of external voltage, electrons from the cathode and holes from the anode migrate from the electron transport layer and hole transport layer to the organic light-emitting layer respectively, recombine in the organic layer, release energy, and the organic light-emitting substance molecules are excited and transition to the excited state. When the excited molecules return to the ground state from the excited state, light is emitted.

The display principle of CSTN is completely different from that of TN. It uses the birefringence of liquid crystal. After the external light enters the polarizer, it becomes a beam of linear polarized light. However, when the linear polarized light passes through the liquid crystal molecular layer, it no longer just distorts the polarization direction, but decomposes into two beams of light - ordinary light and extraordinary light. These two beams of light interfere with each other when they are emitted, so that CSTN always presents a certain background color when it is not powered on.

2. Techniques for distinguishing OLED and CSTN

OLEDVSCSTN two kinds of color screens are mainly distinguished by the following 4 methods.

First, the distinction of colors.

OLED and CSTN are easy to distinguish in the color of the screen. OLED is a self-luminous material that does not require a background light source, so the color is uniform and bright, close to the original effect. However, CSTN has a lower color level and light transmittance than OLED. When displaying a pure black screen, CSTN will still have a very slight background light, making the entire color appear uneven. This is also a typical performance of CSTN.

Second, the difference between wide viewing angle and limited viewing angle.

OLED has a very wide viewing angle, up to 170 degrees. No matter at which angle, we can clearly see the fonts and colors on the display. At the same time, OLED can still see the screen clearly under the sun, while CSTN cannot achieve this effect. The viewing angle is far inferior to OLED. You can only see the color inside from the front of the screen. At other angles, CSTN cannot be seen clearly. Moreover, the CSTN screen will become dark and unclear under sunlight. This is the biggest difference between the two, and it is also the easiest technique to identify.

Third, power effect.

OLED has been recognized by the industry as the next generation mainstream display technology because of its many superior properties. It is thinner, lighter, high-definition, fast refresh rate, low energy consumption, low temperature (performance is still good at minus 40 degrees Celsius), excellent shock resistance, potential low manufacturing cost, flexible and environmentally friendly design, etc., and these are all power consumption. CSTN is slightly inferior in comparison.

Fourth, price.

In the current international market, the price of an OLED screen is about 13-14 US dollars, while that of CSTN is between 5-6 US dollars. It may be difficult for consumers to distinguish the characteristics of the product in terms of price, but consumers should be reminded that if the price of the same 128M or 256M OLED screen MP3 differs by about 100 yuan, it is entirely possible that the merchant is making false publicity.