基于长余辉材料的激光书写和显示

本文给出了长余辉材料一个新的用途,研制了一台以长余辉材料为屏幕的激光书写显示装置,可以人为控制激光笔在余辉材料上随意书写文字、画图并显示.该装置利用单片机和步进电机控制两组轴镜在不同方向的转动,从自己建立的开源矢量图库中调用相关图片,使激光光束在长余辉材料上进行二维矢量的扫描,完成文字书写和绘图显示.用VASP(Vienna abinitio simulation package)软件计算出长余辉材料Mn(H_2PO_4)_2的能级结构,测试了SrAl_2O_4:Eu~(2+),Dy~(3+)和Mn(H_2PO_4)_2的余辉强度衰减曲线,便于调整样机电机的书写速度,测试了Mn(H_2PO_4)_2的反射谱和拉曼谱,其拉曼峰值在625,769和1049 nm及远红外.通过理论和实验研究,掌握了与相应长余辉材料匹配的激发最佳激光波段.制作样机后得到英文、中文、图像的实时书写和显示结果.本装置犹如一只无形的"笔"在纸上挥舞,流畅书写绘画,书写过程配上音乐颇具观赏性,该装置可应用于商业广告显示、动态标语书写、教学投影辅助设备、舞台效果、新型艺术表现形式等领域.

Writing and displaying by the laser on a long lag phosphor material

We make a machine that can perform as an invisible hand able to write and draw smoothly accompanied with the incidental music. And this machine can be used in the commercial advertising display, artmobile poster writing, the accessory equipment of the multimedium classrooms, stage effect, new art pattern especially in dark. We present a new display application of the long lag phosphor (LLP) material in this paper. A prototype is fabricated which can be written, drawn and displayed by controlling a laser beam on the screen which is made from the LLP material. For selecting the match laser beam wavelength for different LLP material screens, the energy band structure of the LLP material Mn(H₂PO₄)₂ of 3-4 eV band gap is calculated by VASP (Vienna abinitio simulation package) software and its Raman shift peaks of Mn(H₂PO₄)₂ are tested at 625 nm, 769 nm, 1049 nm and in far infrared wavelength range. The intensity of powdery LLP SrAl₂O₄: Eu²⁺, Dy³⁺, which is tested by the instrument of UWLA(ultra-weak luminescence analyzer), can decay from 43479 to 9570 electronic counts in 5 min, and then descend slowly. The intensity decay of coated film LLP Mn(H₂PO₄)₂, which is tested by the instrument of HANDYSCOPE HS3, can decay quickly at the beginning and then slowly after 400s. These intensity decay results can explain that LLP materials of SrAl₂O₄:Eu²⁺, Dy³⁺ and Mn (H₂PO₄)₂ are suitable for displaying the image by our prototype. A prototype is successfully made by our group for writing English and Chinese words and drawing picture. Arduino Board is used to control two step motors, and X mirror and Y mirror are rotated to reflect the laser beam. An excitation dot is formed on the surface of LLP display screen. By drawing vectorgragh with Coreldraw and convert it into “.nc” file, the computer runs G-code in CNC (computer numerical control) automatically. Arduino controlled mirror rotation drives the laser beam. The trace of the laser dot is left on the screen and becomes article or graphs in afterglow. The whole device can be energy saving, eyes comfortable, low cost and easy to pick up.