laser is one of the sources that induce a biological effect in higher plants. the positive effect of laser on some crops has been proved. this research was carried out to study the effect of laser radiation on the accumulation of proline in spring wheat (triticum aestivum cv. kavir) under different nacl treatment levels. semi-coherent red beam, infrared beam and one-second harmonics of neodymiu...

Brake beam is one of the important components working in railway vehicles braking process, which directly affects the security and stability of the high-speed running railway vehicles. Through the research of the cutting and welding technology for the 209T straight plate type brake beam, this paper presents an advanced maintenance method, and designs an automatic cutting and welding machine for...

Study of the beam propagation behavior through oceanic media is a challenging subject. In this paper, based on generalized Collins integral, the mean irradiance profile of Gaussian laser beam propagation through ocean is investigated. Power In Special Bucket (PIB) is calculated. Using analytical expressions and calculating seawater transmission, the effects of absorption and scattering on beam ...

Tailor-made blanks are sheet metal assemblies with different thicknesses and/or materials and/or surface coatings. A monolithic sheet can be machined to make the required thickness variations that is referred as tailor machined blanks. Due to the thickness variation in tailor machined blanks, laser bending of these blanks is more complicated than monolithic plates. In this article, laser formin...

Laser cutting is one of the most widely used thermal energy based non-contact type advance machining process. In recent years, considerable experimental investigations have been carried out aiming at improving laser cutting process performance. This review paper aims at presenting the state of the art in the field of CO2 laser cutting of various engineering materials with special emphasis on ex...

This paper presents the results of an experimental and theoretical investigation into the phenomenon of ‘striation free cutting’, which is a feature of fibre laser cutting of thin section mild steel. The paper concludes that the creation of very low roughness edges is related to an optimisation of the cut front geometry when the cut front is inclined at angles close to the Brewster angle for th...

In the traditional laser beam quality measurement, the lens transform method is used to obtain the information of the multi spot, and can only evaluate the beam quality of a continuous or high repetition rate laser, the evaluation speed is slow and the real-time performance is poor. A micro lens array method is proposed, which samples the laser spot only once and obtains all the spot informatio...

Directional dithering of a laser beam potentially limits the detection accuracy of a laser triangulation displacement probe. A theoretical analysis indicates that the measurement accuracy will linearly decrease as the laser dithering angle increases. To suppress laser dithering, a scheme for reduction of the influence of laser beam directional dithering in a laser triangulation displacement pro...

Directional dithering of a laser beam potentially limits the detection accuracy of a laser triangulation displacement probe. A theoretical analysis indicates that the measurement accuracy will linearly decrease as the laser dithering angle increases. To suppress laser dithering, a laser triangulation displacement probe with laser beam pointing control, which consists of a collimated red laser, ...