Coordinate difference homogenization matching method for motion correction in 3D range-intensity correlation laser imaging

This Letter proposes a coordinate difference homogenization matching method to solve motion influence in three-dimensional（3D） range-intensity correlation laser imaging. Firstly, features and feature pairs of gate images are obtained by speeded-up robust figures and bi-directional feature matching methods. The original mean value of the feature-pair coordinate differences is calculated. Comparing the coordinate differences with the original mean value, the wrong feature pairs are removed, and then an optimized mean value is updated. The final feature-pair coordinates are re-registered based on the updated mean value. Thus, an accurate transformation is established to rectify motion gate images for 3D reconstruction. In the experiment, a 3D image of a tower at 780 m is successfully captured by our laser gated imaging system on a pan-tilt device.

Enhanced piezoelectricity of Cu-doped K(Ta,Nb)O_(3) single crystals

As a class of solid solution material,K(Ta,Nb)O3(KTN)single crystals have attracted significant interest due to their excellent piezoelectric and electro-optic performance.In this study,the piezoelectric properties of KTN were improved through Cu doping.Utilizing the advantages of composition-regulating phase transition,a large,high-quality Cu:KTN crystal measuring 30 mm×25 mm×20 mm in size was grown using the improved top seeded solution growth method.Cu-doped KTN exhibited better piezoelectric properties than pure KTN,and the full matrix parameters were investigated.Excellent dielectric,piezoelectric,and electromechanical coupling responses(ε^(T)_(11)-2,136,d_(33)∼303 pC/N,k_(t)∼0.515,and k33∼0.672)were successfully obtained.To realize the optimized orientation of the piezoelectric properties,the orientation dependence of the single domain properties was investigated,and the mechanism of Cu doping to improve piezoelectric properties was explored.We found that 0.36%(in mass)Cu doped crystal consisted of A-site substitution,following ferroelectric and domain analysis.The small ferroelectric domain sizes led to a large domain wall mobility rate and high domain wall density,which contributed to high piezoelectric properties.This work revealed the effect of A-position doping on piezoelectric properties and provided a theoretical and experimental foundation for the performance optimization of KTN-based materials.