Positive and Negative Mode LCD Displays

Blaze Display Technology Co., Ltd. | Updated: Nov 27, 2018

LCD displays have two display modes, Positive mode and negative mode. Positive mode is dark characters on a light colored background, Negative mode is lighter colored characters on a darker background.

 

Positive Mode LCDs

Positive mode displays have the advantage of their lighter background and no backlights are needed. They normally use transflective or reflective polarizers and have lower power consumption. They can be seen with ambient light.

 

Negative Mode LCDs

Negative mode displays need backlit in order to be seen. They normally use transmissive polarizers. They have better contrast and wider viewing angles in the indoor dim environment. The readability is much better than positive displays.

 

But under bright ambient light or even under direct sunlight, the displays will be easily washed out. In order to be seen under the bright surrounding light, the backlight brightness has to be increased to over 800 nits. The sunlight readable displays consume much power.

 

 

 

Which is better, Positive or Negative LCDs?

That depends on your application.

You can choose Positive LCDs if you are looking for:

– Low cost;

– Low power consumption with battery as main power resources;

– Used in outdoor or bright ambient light.

 

You can choose Negative LCDs if you are looking for:

– Used indoor or low light environment;

– Sharp or catching images or contrast with better viewing angles;

– Night vision with green or black background, such as aviation panels, bedside alarm clock etc.

 

Of course, we can always use LED backlight in the LCD module with fewer LED chips and turn off LED backlight when not use to save power. When can also add transflective polarizer to some negative LCDs to make it sunlight readable, but the contrast will be compromised.

 

Positive and negative mode concept is not only limited to monochrome LCD displays (LCD panels, character LCDs, graphic LCDs etc.), it also uses for color displays, or even other display technologies.  We will categorize the displays as below,

 

Positive Displays:

– Positive TN LCDs

– HTN LCDs

– Yellow Green STN LCDs

– Gray STN LCDs

– Positive FSTN LCDs

 

Negative Displays:

– Negative TN LCDs

– Blue STN LCDs

– Negative FSTN (Film Compensated STN) LCDs

– VTN (Vertical Alignment or VA) LCDs

– FFSTN (Double Film FSTN) LCDs

– TFT (Thin Film Transistor) LCDs

– IPS ( In-Plane-Switching) LCDs

– AFFS ( Advanced Fringe Field Switching) LCDs

– OLED Displays including PMOLED (Passive Matrix Organic Light Emitting Diode) and AMOLED (Active Matrix Organic Light Emitting Diode)