Graded-index (GRIN) fiber lens arrays are fabricated from commercial GRIN fibers to collimate a high-power laser diode array. The beam divergence angles are reduced to 4.2 and 14.7 mrad in the fast and slow axes, respectively. The influences of smile and fluctuation in fiber length are discussed. Using an aspherical focal lens system, about 74% power can be launched into a fiber with a numerical aperture (NA) of 0.22 and a core diameter of 400 µm.
Demonstrations of CW lasing in ceramic Cr2+:ZnSe are reported. The laser consists of a 1.7-mm
thick ceramic Cr2+:ZnSe disk pumped by a double-clad Tm-silica fiber laser at 2050 nm. Using a
concave HR mirror with a radius of curvature of 500 mm as the rear mirror, the laser delivers up to
1030mW of radiation around 2.367 μm.
Based on the idea of multi-resolution model, this article proposes a quarter-tree multi-resolution model of three-dimension terrain and a simplification algorithm. The author's starting point is: Firstly, it is necessary to normalize the basic model and re-sample the normalized grid by means of quarter-dividing them. Secondly, to obtain a refined model with encrypted sampling technology. With the grid being sampled, the normal vector of each mesh and MSD (mean square deviation) of normal vectors in the adjacent four meshes are also calculated. The process of encrypted sampling will continue until the requirement of the system resolution is fully satisfied. And, finally, a quarter-tree multiple resolution model of 3D terrain has been set up by the author from top to down, thus making the model much simplified with error control and mesh emerging technology on the real-time drawing basis. Tested by a series of experiments and measurements, the algorithm has proved to be highly efficient in model simplification and convenient to be put into practical application.
In the industrial process of welding, there are kinds of stress that deform the weidment and reduce the precision of welding. Through sampling and processing the ESPI stripe-images, which generate from the process of welding, finally the skeletons of these images can be extracted. Since these skeletons represent the movement of dynamic displacement fields, the ultima aim of processing ESPI stripe-image is to control the process of welding, to debase the degree of distortion for the weldment, consequently to heighten the precision of welding. On the basis of analyzing the characteristic of ESPI stripe-images, this paper bring forward the thought of integrated design, thin these images and extract its skeletons after gray transform, histogram equalization, filtering noise and binarization.