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Abstrak :
ABSTRAK
Pada proses engraving penggunaan laser berdaya tinggi marak digunakan saat ini. Laser daya tinggi yang sering digunakan adalah laser gas seperti CO2, Nd:YaG dan laser diode. Laser diode memiliki beberapa kekurangan diantaranya sudut divergensi lebar, astigmatisme dan beam profile yang tidak ideal yang berbentuk elips. Kekurangan tersebut menyebabkan kualitas beam profile yang buruk. Oleh karena itu perlu dilakukan koreksi beam pada output diode untuk mengurangi rasio elips yang dimilikinya. Metode koreksi yang umum dilakukan adalah dengan menggunakan dua lensa silinder untuk melakukan koreksi pada sumbu horisontal dan vertikal.Pada tesis ini telah dikembangkan metode koreksi output beam berbasis pada ray tracing analysis untuk menghitung struktur susunan lensa yang meliputi pengaturan fokus dan jarak antara lensa ndash; lensa silinder yang digunakan untuk mengurangi rasio elips serta lensa pemfokus untuk mendapatkan ukuran beam yang diinginkan. Hasil experiment terhadap metode koreksi beam diamati melalui dua cara yaitu; 1 pengamatan burning spot dengan mikroskop digital dan 2 menghitung hasil foto menggunakan MATLAB. Hasil kedua metode ini menunjukan pengurangan rasio elips. Pengurangan rasio elips dari 1.43 menjadi 1.14 pada pengamatan burning spot. Selain itu, dilakukan pula karakterisasi kebutuhan intensitas terhadap waktu pembakaran beberapa objek material.

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ABSTRACT
In the process of engraving the use of high power lasers are rife in use today. The most commonly used high power lasers are gas lasers such as CO2, Nd YaG and also semiconductor, laser diodes. Laser diodes have some disadvantages such as wide divergence angles, astigmatism and elliptical beam profile. These deficiencies cause poor beam profile quality. Therefore it is necessary to do beam correction at the output diode to reduce the ratio of the ellipse it has. A common method of correction is to use two cylindrical lenses to correct the horizontal and vertical axes.In this paper use this ray tracing method for focus setting, the distance on the cylinder lenses and the focusing lens are used to reduce the ellipse ratio and obtain the desired beam size. The experimental results of the beam correction method were observed in two ways 1 observation of spot burning with digital microscope and 2 calculate the result of photo using MATLAB. The results of both methods show a reduction in the elliptical ratio. The reduction of the ellipse ratio is from 1.43 to 1.14 on the observation of burning. In addition, there is also characterization of the need for intensity to burning time of some material objects.

Abstrak :
ABSTRACT
A vacuum chamber has been designed and constructed for the observation the primary plasma and secondary plasma which is generated by the bombardments of brass by N2 Laser beam with about 5 ns pulse width and 1 1W power.

The Radius and spectral emission of the resulting secondary plasma of the brass sample at the surrounding gas pressure range 2 and 8 torr in N2, is presented.

This study can be developed to generated plasma and it can used for the analysis the composition the sample irradiated by N2 laser beam.

Abstrak :
This book mainly addresses the applications of lasers in the manufacture of various industrial components. The technologies presented here have scopes of application ranging from the macro to meso and micro level of components and features. This book includes chapters on the basic and advanced applications of lasers in the manufacturing domain. They present theoretical and practical aspects of laser technology for various applications such as laser-based machining, micro-scribing, texturing, machining of micro-sized channels; laser welding; laser-based correction of sheet metal, i.e. straightening; laser forming; and laser technology for 3-D printing. Lasers have various applications such as the production of powerful lights for illumination or decoration; measurement of velocity (transportation) and length; interferometry; printing; recording; communication; bio-medical instrumentation and pollution detection. A significant body of literature is available on the physics of lasers and types of lasers. However it has been noted there are a few books published on the “applications of lasers in manufacturing domain,” a gap that this book remedies. Gathering contributions by leading engineers and academicians in this area, it offers a valuable source of information for young scientists and research students.