TN偏振旋转器
扭曲向列(Twisted Nematic,TN)液晶是显示行业中最常用的液晶类型。TN盒本质上是90°液晶偏振旋转器。当线性偏振光进入液晶盒时,它会沿着从前玻璃基板到后基板形成的液晶螺旋结构旋转。TN盒可以制作为常黑模式或常白模式。
- 常黑模式:在无电压施加时处于暗态,偏振器平行安装在基板外侧。随着电压的施加,透光率随电压增加而增加。
- 常白模式:在无电压施加时处于最大透光状态,偏振器正交安装在玻璃基板上。随着电压的增加,光被衰减。这种模式由于利用了交叉偏振器配置,能够实现更高的对比度。
TN的优势包括低电压需求以及在宽波长范围内的操作能力。TN盒可以使用薄玻璃大规模均匀制造。如果需要低透射波前失真,可以使用抛光玻璃基板制造精密液晶盒。
PRECISION TWISTED NEMATIC (TN) LC DEVICES
BVO DEVELOPMENTAL LIQUID CRYSTAL LAB
Glass | Eagle XG Display Glass or Polished Fused Silica |
Thickness | 1-2mm thick: Thin devices made with standard display glass 6-8mm thick: Low wavefront distortion devices made with fused silica |
Outer Dimensions | Maximum Size – 90mm | Minimum size – 12mm |
Clear Aperture (CA) | 2mm internal gasket & 2mm landing |
Buffing | 90˚ orthogonal |
Transmitted Wavefront Distortion | Polished glass devices: .25 waves over clear aperture |
BBAR Coatings | Optional coatings |
Contrast Ratio | 1000:1 |
Switching Speed | 1 Milli Second (Rise Time) / 15 Milli Seconds (Fall Time) , Typical |
Bandwidth | Visible or Near infrared |
Temperature Range | 10˚ C to 60˚ C |
Damage Threshold | 500 Watts/cm2 CW .5 Joules/cm2 10nsec pulses @ 1064nm typical |