The optical axes can be structurally distinguished into two types, one called a hollow shaft axle and the other called a solid shaft. If the material and the cross-sectional area are all in the same state, then the hollow shaft axle has a stronger torsional resistance than the solid shaft compared to the solid shaft, and can carry a relatively large external force, and the hollow shaft axle is used for comparison. Can save materials. However, if the stress distribution from the circular surface is the case, the maximum shear stress of the solid shaft on the circumference is very similar to that of the hollow shaft, except that the shear stress in the middle portion is compared with the shear stress of the hollow shaft. The difference is far, and the material in the middle of the solid shaft can not fully play its role, the cost is much higher than the hollow shaft, and the program is more difficult when making and processing. However, these two kinds of applications are widely used, and the scope is very wide, especially for mechanical packaging. However, if you have to say which kind of application is more extensive, you have to judge the actual situation according to your own needs. .https://www.xhychromerod.com/