We theoretically and experimentally investigate the generation of square optical bottle, which are generated by
double Airy beam induced by binary phase pattern. A regulable linear factor is introduced into phase function to
modulate flexibly the size of optical bottle. Numerical simulations are performed and experimental results also
show that Gaussian beam can be shaped into square optical bottle by a tunable binary cubic phase pattern. The
linear factor can vary the region size of zero or low intensity of optical bottle. It is believed that the intriguing
characteristic of square optical bottle can be applied in many applications such as optical tweezers, atom
trapping and manipulating.
An effective approach to measure image motion is presented based on joint transform correlator(JTC), in order to measure the sub-pixel image motion caused by satellite attitude instability or vibration. Firstly, the high-speed CCD is used to capture image sequences, which are preprocessed by wavelet edge detection. Next the acquired image edge sequences are optically calculated by JTC, and an improved correlation peak is obtained. Lastly a modified centroid algorithm is proposed to get more accurate motion measurement. Motion measurement based on optical correlation is discussed, and the optical experiment system is also set up. The experimental results show that the measurement error is as low as 0.02 pixels, the accuracy is improved greatly.
It is difficult to dectect and recognize moving target for optical correlator owing to the image information containing various rotation and scale variation, though optical processing owns the advantage of high-speed, large capacity and real-time. An efficient approach was proposed to impove correlation peak and enhance recognition performance of target based on Fourier-Mellin transform, by which optical correlator is not sensitive to the distortion of image information, and it will alleviate greatly the complexity of image recognition. We have also constructed an detection and recognition system based on optical joint correlator, the computer simulations and experimental results show that the proposed method has got sharp corrlation peak and improved the detection performance.
To restore the motion blurred image caused by various vibration and attitude variation in remote
imaging, an approach is presented which is based on joint transform correlator (JTC). An auxiliary
high-speed CCD is used to capture image sequences When the prime CCD is imaging in exposure
period, these image sequences are optically calculated by JTC system, and image motion vector can be
effectively detected and point spread function is accurately modeled instantaneously, it will alleviate
greatly the complexity of image restoration algorithm. Finally, a simple restoration algorithm is
proposed to restore the blurred image. We have also constructed an image restoration system based on
joint transform correlator. The experimental results show that the proposed method has improved
image quality greatly.