Dr Pan:Welcome to DISPLAY Museum. I am Dr Pan, the curator of Museum.

Greg: Hello, Dr Pan. I am Greg. I came here to learn about TN LCD Screen. 

Dr Pan: Hello, Greg. TN is the abbreviation for Twisted Nematic. The main difference between TN, HTN, STN and FSTN LCD is the view angle. From the definition, the maximum view angle of TN LCD is 90°. Take this TN positive LCD for example. The view angle is 6 o’clock direction and it can be seen very clearly in the 6 o’clock direction and the front side.

 When it is a positive and reflective display, it can display without LED backlight; when it is a positive and transmissive/ transflective display, it can’t display without LED backlight, the background color is grey and the letters are black.

When it is a negative and transmissive/ transflective display, it can’t display without LED backlight, the background color is purple-black, different colors from different view angle, and the color of the letters is the color of LED backlight.

By the way, no matter it is a positive or negative display, the background color is affected by the color of LED backlight on some level. That is why the color of LED backlight is usually white.

Theoretically, we can add a blue film to TN negative LCD, it may look like this. Actually, from our experience, no one has done it before since HTN or STN negative LCD with blue background looks better with wider view angle.

     TN LCD is the most commonly used since it is the cheapest. The maximum COM is 4, so it can’t display too many segments, and it can’t be used in the high end devices. But it performs very well in the simple display content: calculator and alarm clock.

Greg: Thank you, Dr Pan. Now I got it.

Dr Pan: Welcome to contact us if you have any questions.