Yu Huijun, Zhou Peng, Wang Kewei, Huang Yanfei, Shen Wenjiang
School of Nano-Tech and Nano-Bionics, University of Science and Technology of China, Hefei 230026, China.
Key Lab of Nanodevices and Applications, Suzhou Institute of Nano-tech and Nano-bionics, Chinese Academy of Sciences, Suzhou 215123, China.
Micromachines (Basel). 2020 Jun 30;11(7):651. doi: 10.3390/mi11070651.
In scanning laser projection systems, the laser modulation time is important for the projection resolution. The modulation time needs to be matched with the motion of the micromirror. For this paper, the piezoresistive sensor was integrated on the torsion beam of the micromirror to monitor the physical position of the micromirror. The feedback signal was used to generate the zero-crossing time, which was used to estimate the physical position of the resonating mirror over time. The estimated position was affected by the zero-crossing time and the error directly influenced the definition of the projected image. By reducing the impurity concentration from 3 × 10/cm to 1 × 10/cm and increasing shear stress on piezoresistive sensor, the sensitivity of the piezoresistive sensor increased from 4.4 mV/V° to 6.4 mV/V° and the error of the image pixel reduced from 1.5 pixels to 0.5 pixels. We demonstrated that the image quality of an Optical-Microeletromechanical Systems (MOEMS) laser projection could be improved by enhancing the sensitivity of the piezoresistive sensor.
在扫描激光投影系统中，激光调制时间对投影分辨率很重要。调制时间需要与微镜的运动相匹配。在本文中，压阻式传感器集成在微镜的扭梁上，以监测微镜的物理位置。反馈信号用于生成过零时间，该过零时间用于随时间估计谐振镜的物理位置。估计位置受限于过零时间，且该误差直接影响投影图像的清晰度。通过将杂质浓度从3×10/cm降至1×10/cm，并增加压阻式传感器上的剪应力，压阻式传感器的灵敏度从4.4 mV/V°提高到6.4 mV/V°，图像像素的误差从1.5像素降至0.5像素。我们证明，通过提高压阻式传感器的灵敏度，可以改善光学微机电系统（MOEMS）激光投影的图像质量。
