https://www.selleckchem.com/products/sr-717.html Self-mixing interferometry (SMI) is a reliable method that has been applied to measuring displacements, absolute distances, and velocities of remote targets. Evaluating the optical feedback factor C and the linewidth enhancement factor α is a vital step in calculating laser diode parameters and in processing SMI signals using phase unwrapping. This paper proposes an evaluation method for the optical feedback factor and the linewidth enhancement factor of arbitrary waveforms by investigating the slopes of phase discontinuity distribution in the optical feedback regime of 1 less then C. First of all, the effects that the slope of phase discontinuity distribution has on the prediction of the optical feedback factor and the linewidth enhancement factor are clarified. Next, an algorithm is proposed to evaluate the optical feedback factor and the linewidth enhancement factor using the slope variation of phase discontinuity distribution, along with a method to select discontinuities in order to improve measurement accuracy using the cumulative effect of discontinuity distribution. The proposed method is verified through simulations as well as experiments with a low-cost semiconductor laser.We fabricated a binary diffractive lens to control focal distribution, such as intensity distribution, by controlling the focal length and depth of focus. The results revealed changes in the focal length and depth of focus as a function of changes in the ring zone interval ΔRM at the end of the lens. Similar results were obtained from experiments. The peak position on the optical axis shifts further away from the lens. The half-width in the propagation direction increases with the ΔRM. These results demonstrate the possibility of controlling the focal distribution using single flat lenses by changing the periodic structure.In this experimental work we report our findings about a cascade (Ξ) transition 5S1/2→5P3/2→5D3/2 of both 85,87Rb atom