摘要
提出一种位相调制的实时联合变换相关器。它采用液晶显示屏作为输入器件，用液晶光阀记录和显示联合功率谱。利用液晶显示屏上的光栅状结构的衍射级，提高光能的利用率，并充分利用液晶光阀的有效使用面积。采用成像透镜放大各衍射级的联合频谱，适应液晶光阀较低的分辨率要求。在相关器的光路中插入两块倾斜的平行平面玻璃板，以改变各衍射级的参考图像和目标图像之间的位相差。这种方法可产生比传统的实时联合变换相关器更好的输出相关性能。
A phase modulated real time joint transform correlator is proposed, in which a liquid crystal display screen is adopted as an input device and the joint power spectrum is recorded and displayed by a liquid crystal light valve. The diffraction orders of the grating type structure on the liquid crystal display screen are utilized in this system. As a result, it can use the light energy as well as the physical area of the liquid crystal light valve more efficiently. In order to suit low resolution of the liquid crystal light valve, an imaging lens is applied to amplifying joint frequency spectrum of the diffraction orders. The two oblique parallel plane glass plates are inserted in the correlator to manipulate the phase differences between the reference image and the target image of the diffraction orders. This technique yields better output correlation performences than the classical real time joint transform correlator. The experimental results verified the correctness of the system design and performance analysis.
出处
《光学学报》
EI
CAS
CSCD
北大核心
1997年第4期456-460,共5页
Acta Optica Sinica
基金
福建省自然科学基金
关键词
实时
联合变换
相关器
光学图像识别
位相调制
real time joint transform correlator, optical pattern recognition, phase modulation.
