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"ABSTRACTThe frequency dobled Rd: YAG laser (532 nm/10ns, 15mj/pulse) uses a pulsed, frequency dobled; which provides a monochromatic, energy source with extremely high peak power and to has capability to develop of latent fingerprint on various surface. In the porous surfaces, this laser to has superiority, the compared with the development another methods, like powder and chemical method in latent fingerprint development. The high peak power of the laser causes Palmar sweat: contain a variety compounds, among them amino acids, oils, enzymes, vitamins and other chemicals with in the print to fluoresce. Some latent fingerprints will fluoresce in their natural state during exposure to this laser energy. The natural state fluorescing prints make can be documented and recording by high-resolution TV cameras and monitor for maximum sensitivity. The next step, the compare latent fingerprints products with visible impression by comparable instruments, see patterns of the friction ridges and be found same amount of their galton detail. "

"ABSTRACT

Probing of the atmospheric parameters have been done by many scientists since a century ago up to present with various techniques. A simple system of laser radar without using any collimated beam but a reflected mirror as transmitter and a small cassegranian type (10.5 an in diameter) telescope as receiving was constructed to investigate the relative Mie backscattering coefficient by utilizing a nitrogen laser as a light source in the range of measurement bellow 1 Km. The backscattered light received by the receiving telescope is converted into electric current by photomultiplier and is shown and known as "A scope" display on an oscilloscope. SNR of the signal from photomultiplier was increased by using a boxcar integrator and its output could be recorded with XY recorder."

"ABSTRACTLaser induced thin film production (LITFP) technique was employed for making plumbum (Pb) thin film by nitrogen laser deposition in miniature scale. The energy of nitrogen laser operated at 12.5 kv, 90 torr was 3.5 mj with 5 ns pulse duration, thus producing peak power at around 0.7 MW. Pb plasma of 1 cm diameter was generated in each laser bombardment, producing thin film above the glass substrate. The thin film characteristics were measured by means of their thickness and surface morphology using scanning electron microscope (SEM). It was proved that there was a linear relationship between the number of laser shots and film thickness."

"Kopling antara amplifier permukaan miring dan fiber taper lens-ended diselidiki secara teori. Penelitian teori didasarkan pada model gelombang bidang tiga dimensi yang dihitung melalui pergeseran fasa akibat permukaan iring. Kopling diselidiki berkenaan dengan parameter-parameter berkas dari pandu gelombang amplifier lens-ended, dan juga berkenaan dengan posisi fiber. Terjadinya rugi-rugi kopling karena permukaan miring dan karena variasi dari uji lens yang terbaik, rugi untuk permukaan miring 10° ditemukan lebih kecil dari 0.5 dB dibandingkan amplifier permukaan normal.

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The coupling between angled-facet amplifiers and tapered lens-ended fibers is investigated theoretically. The theoretical investigation is based on a three-dimensional plane wave model which accounts for the phase differences introduced by the angled facets. The coupling is investigated with respect to the beam parameters of the amplifier wave guids and the tapered lens-ended fiber, and also with respect to the fiber position. For optimized lens radii the excess loss for 0l0° facet angle is found to be less than 0.5 dB compared to a normal facet amplifier."

"The purpose of this reserach is to find out the influence of laser shooting to the ovaries stem of eye,ablation of crab's eye to the level of egg's maruty,the diameter of eggs and the number of eggs scylla serrata....."

"ABSTRACTIn spite of abundant experimental evidences supporting the viability of the laserinduced shock wave plasma model for the explanation of the important features oftheplasma and the associated spectroscopic characteristics, a controversy on the atomicexcitation mechanism in the plasma has remained to be completely resolved. In thisstudy the contributions of the shock wave model and two other most popular models,the electron-ion recombination model and thc electron collision model werethoroughly investigated. For that purpose, a special technique has been developed forthe direct detection of the charge current in conjunction with plasma emissionmeasurement dining the laser plasma generation and expansion. The current detectionwas performed by placing a partially transmitting metal mesh electrode at a distancein front of the sample surface with the sample target sewing as the counter electrode.The electric Held between the mesh and sample surface was set up and varied byapplying a variable DC voltage (0-400 Volt) between them. The laser plasma wasgenerated by a YAG laser (64 ml, 8 ns) tightly focused on a Cu target through themesh electrode in low-pressure surrounding gas. It was found that the charge currenttime profiles obtained at various gas pressures invariably exhibit a lack of consistentcorrelation with the emission time profile of the plasma throughout most of theemission period. The result of this study has thus practically eliminated anysignificant roles ofthe electron-ion recombination and electron collision models in theexcitation process. We are therefore led to conclude that the shock wave modelproposed earlier is most plausible for the consistent explanation of the secondaryplasma emission, while the other two models may have some contribution only at thevery initial stage ofthe secondary plasma generation.Key words: charge current, shock wave, electron-ion recombination and electroncollision.Praiseci is to the Lord for He is my reason in everything I do.This manuscript is never be done without the guidance by Pro£ Tjia May On, towhom I am extremely grateful. He also provided the support without which this thesiswould not possible. He is more than just a teacher for me for his words have deeplytouched me. Moreover, he also introduced me that knowledge is something we shouldshare among others and to improve the education in my country.I am also indebted to Prof. Kiichiro Kagawa at the Fukui University for providingthe atmosphere and the physical resources to make thesis writing in these times of fastpaced research. I am also thankful for the opportunity which is given to me to joinresearch together with him in his laboratory in Japan.Extra special thanks go to Dr. Hendrik Kurniawan for providing me withencouragement and support for this project. He is the first one who encouraged me totake Doctor Cotuse Program which seemed impossible at the beginning. Hiscompanion during research at Applied Spectroscopy Laboratory at University ofIndonesia is a leading experience in research for me.I am particularly grateful to the excellent team of referees who provided criticalcomments on this thesis. Their feedback was a great benefit to me.I gratefully acknowledge all my colleagues: Rinda Hedwig, Mangasi A.Marpaung, Hery Suyanto, MM. Suliyanti, Wahyu S. Budi, and Emon in AppliedSpectroscopy Laboratory at University of Indonesia, for their assistance and supportduring my study.My never-ending thanks to my beloved family, especially to my parents whoexhibited thoughtful patience over extended periods of time when I seemed to beinvisible. Thanks also to Loviana who helped me in all situations which I no longercan resist by myselflFinally, I apologize to all those who helped that I did not acknowledge specifically.I know there were many and greatly appreciate your assistance.August, 2002Author"

"A special interferometric technique with high sensitivity has been devised on the basis of rainbows refractometer without the use of an additional and delicate amplitude-splitting setup. This new technique was use for the characterization of shock wave plasma induced by a Q-sw Nd-YAG laser on various kinds of metal samples under reduced gas pressures. An unmistakable signal of density jump was detected simultaneously with the emission front signal. It is proved that at the initial stage of the secondary plasma expansion, the front of the emission and the front of the blast wave was coincide and move together with time. However, at a later stage, the front of the emission will separate from that of the blast wave induced in the surrounding gas at low pressures. Using Cu and Zn samples, the experimental result showed that the separation of the emission front and blast wave front took place at 4 mm above sample surface for the laser energy of 140 mJ."