PDF(Pubmed)
Abstract：
We demonstrate the fabrication of good quality surface alignment layers on glass by Direct Laser Writing method using a 2-photon polymerisation technique. We use commercially available photosensitive resins to print alignment layers by scanning the focal point of a femtosecond laser near the resin-glass interface. This results in down to ~ 100 nm thin alignment layers that provide good planar anchoring of 5CB and MLC13300, with the easy axis of alignment along the scanning direction. The azimuthal anchoring strength is ~ 5 × 10-6 J/m2 and is an order of magnitude weaker compared to commercial rubbed polyimide alignment layer. The threshold voltage for Fréedericksz transition in a 90° twisted nematic cell is slightly increased compared to conventional rubbed polyimide for printed alignment layers. The turn-on switching time is longer for printed layers compared to polyimide alignment layers, whereas the turn-off time is shorter for printed alignment layers. The advantage of this new method is in its flexibility, as we demonstrate printing of complex surface alignment patterns with alignment layer thickness below 100 nm.
摘要：
我们展示了使用2光子聚合技术通过直接激光写入方法在玻璃上制造高质量的表面对准层。我们使用市售的光敏树脂通过在树脂-玻璃界面附近扫描飞秒激光的焦点来印刷对准层。这导致低至〜100nm的薄对准层,其提供5CB和MLC13300的良好平面锚定,具有沿扫描方向的容易对准轴。方位角锚固强度为〜5×10-6J/m2,并且与商业摩擦的聚酰亚胺取向层相比弱一个数量级。与用于印刷对准层的常规摩擦聚酰亚胺相比，90°扭曲向列电池中的Fréedericksz跃迁的阈值电压略有增加。与聚酰亚胺对准层相比，印刷层的导通切换时间更长，而对于印刷的对准层,关断时间更短。这种新方法的优点在于它的灵活性,如我们展示了具有低于100nm的对准层厚度的复杂表面对准图案的印刷。
