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"ABSTRACTFor the purpose of optically cooling, trapping, detecting and accelerating Cesium atoms in a "fountain clock", semiconductor lasers with external resonator have been designed, built and tested in their spectral characteristic and their long-term frequency drift. Multiple Quantum Well lasers with AR coating on one end face and a high reflection coating on the other end face have been used which produce 50 mW at 852 nm ( single end output ). With an external grating resonator the line width was reduced to 150 KHz. Doppler emitted and saturated absorption spectra of the two Cs fine structure transitions were recorded. The saturated absorption lines (Lamb dips) were utilized as optical discriminators in order to stabilize the laser frequencies off line center as is required for optical cooling. Beat frequency measurements between two external resonator laser diodes permitted to measure the 150 KHz line width, and to observe the quality of the long-term frequency stabilization. "

"ABSTRACTThe principles of frequency stabilization is to keep constant the optical path length in laser cavity by controlling the laser- tube length. In this system used temperature servo control to control the laser tube length.As reference to an error derived by a sensitive frequency discriminator. Basically the operation of this sensitive frequency discrimantor utilized the longitudinal Zeeman Laser, which splits atomic gain profile.When a longitudinal magnetic field is applied to an internal mirror of single mode He-Ne Laser, the active medium acquires a negative circular dichroism. There fore the intensity of the left cicular polarization (LCP) output of the, laser will be different from the intensity of the right circular polarization (RCP) output and only when the two are simmetrically disposed about the center line will their intensities be equal. This intensity difference as feedback can be detected by passing the output beam throught Wallaston prism and the two orthogonally polarized beams are received by two identical photodiodes. The difference between the output of photodiode as amplified and the resulting signal is passed throught a system controller (PID) before it is fed back as heating or cooling current of peltier elements. This current controls the resonator length thermally and lock the laser frequencies of the two polarized beam symmetrically on either side of the profile."

"ABSTRACTThe molecular weight of Polymer material can be determined using optical system by measuring the intensity of scattered light at low angle light scattering and its the incident beam, based on Rayleigh scattering have developed by Debye has known as Static Light Scattering. To carry out this measurement, an optical system was constructed using a HeNe laser light with a certain intensity, and the light passed through a polymer solution and its scattered light were then detected using a photo multiplier. To obtain the experimental results, the set-up was tested using a polymer standard, which has been already known its average molecular weight. In this experiment were used the polymer standard with average molecular weight 35000, 110000 and 200000. Furthermore, this optical experiment set-up constant, were used for determining the average molecular weight of the polymer samples. In this experiment a linear curve relation between the optical Rayleigh polymer and the polymer concentrations was constructed, and by extrapolating this linear curve up to zero concentration the molecular weight of polymer can be determined. From the laboratory test we got that the experimental set up could be used for the measurement of polymer, which has the molecular weight larger than 35000 to 200000, with tolerance 4 percent."

"This new edition features numerous updates and additions. Especially 4 new chapters on fiber optics, integrated optics, frequency combs and Interferometry reflect the changes since the first edition.In addition, major complete updates for the chapters, optical materials and their properties, optical detectors, nanooptics, and optics far beyond the diffraction limit. "