Vertical alignment display has many names depending on different manufacturers. Orient Display named it VTN (Vertical Type Nematic), or PMVA (Passive Matrix Vertical Alignment), or GDV (Goworld Display Vertical), or IBN (Improved Black Nematic). No matter what it is called, the main difference between VTN and TN/STN is the alignment. For VTN, the LC molecules are aligned perpendicularly to glass substrate. Please see Fig. 1 and Fig. 2 below.

Fig. 1  Vertical alignment LCD	Fig. 2 TN LCD

Features of Vertical Alignment LCD

• True black background

• Ultra high contrast ratio:

  • If duty<1/8 : 1000:1 or even higher

  • If 1/16≥duty≥1/8 : 200:1 or even higher

• Ultra wide viewing cone

• Temperature independence

• Background color doesn’t change at -30 °C~80 °C

• Suitable for all different color backlights

Different Types of VTN LCD

There are different types of VTN LCDs.

1. General Vertical Alignment LCD

This type of VTN LCD is designed for low cost and low multiplex applications. The typical parameters are exampled as below.

• • • • Operation Temperature: -20 °C~70 °C
      • Storage Temperature: -30 °C~80 °C
      • Contrast Ratio: > 1000:1
      • Duty: static ~1/5
      • Driving Conditional 

      1/4duty, 1/3bias: 3.5V~5.0V

                 (3.0V @70 °C Storage)

      Static : 2.6～4.5V 

                 (2.2V @70 °C Storage) 

• • • • Viewing cone @CR ≥ 20:1

      Vertical: +60° to -20°

      Horizontal: ±60°

Fig. 3 General Vertical Alignment LCD

2. High Multiplex (Duty) Vertical Alignment LCD

This type of VTN LCD is designed to drive up to 160 multiplex segments or dot matrix display. The typical parameters are as below.

• • • • Operating temperature: -20 °C~70 °C
      • Storage temperature: -30 °C~80 °C
      • Contrast Ratio: > 200:1
      • Duty: ≤1/160  
      • Operating Voltage: 4.5V~8.0V @1/8 duty

5.0V~10.0V @1/16 duty

• • • • Viewing cone @CR ≥ 5:1

Vertical: +60° to -10 °

Horizontal: ±60°

Fig. 4 High Multiplex Vertical Alignment LCD

3. High Reliability Vertical Alignment LCD

This type of VTN LCD is designed for harsh environment, most of them are designed for automotive. The typical parameters are exampled as below.

• • • • Operating Temperature: -30 °C~80 °C
      • Storage Temperature: -40 °C~90 °C
      • Reliability test: 80°C × 90%RH × 500H
      • Contrast Ratio: > 1000:1
      • Duty: static, static ~1/4
      • Operating Voltage:

      4.5V~5.0V @1/4 duty

• • • • Viewing cone @CR ≥ 20:1

      Vertical: +60° to -20°

      Horizontal: ±60°

Fig. 5 High Reliability Vertical Alignment LCD

4. Full Viewing Angle Vertical Alignment LCD

The normal VTN LCD has a dead spot viewing angle. Full Viewing Angle VTN LCD is designed to have good contrast for all the viewing angles. The typical parameters are exampled as below.

• • • • Operation Temperature: -20 °C~70 °C
      • Stoarage Temperature: -30 °C~80 °C
      • Contrast Ratio: > 1000:1
      • Duty: static

      Vop: 2.6V~4.5V

• • • • Viewing cone @CR ≥ 20:1      

      Vertical: ±60°

      Horizontal: ±60°

Fig. 6 Full Viewing Angle Vertical Alignment LCD

5. Field Sequential (FS) Color VTN LCD

FS LCD is not a full color LCD, it can realize maximum 8 colors at one segment. It is better to be designed to be less than ½ duty otherwise the color saturation will be low. The typical parameters are exampled as below.

• • • • Operation Temperature: 0 °C~70 °C
      • Storage Temperature: -30 °C~+80 °C
      • Duty: Static
      • Contrast Ratio:  > 500:1
      • Vop:  

Vdd 3.0~5.0V

• • • • Viewing cone @CR ≥ 10:1

Vertical: +60° to -10°

Horizontal: ±60°

• • • • Color: 8 colors

Fig. 6 Field Sequential (FS) Color Vertical Alignment LCD

Applications

Vertical Alignment LCDs are widely used in automotive, appliances, consumer products

Fig. 7 Vertical Alignment for Refrigerator	Fig. 8 Vertical Alignment for Coffee Maker
Fig. 9 Vertical Alignment for Medical	Fig. 10 Vertical Alignment for Automotive

Comparison with different Technologies