DIFRAKSI FRAUNHOFER CELAH TUNGGAL DENGAN DAN TANPA MENGGUNAKAN LENSA POSITIF SEBAGAI PEMFOKUS

Abstract

The study about Fraunhofer's diffraction to determine the comparation between Fraunhofer’s diffraction pattern by use of lens as focusing and Fraunhofer's diffraction without lens, was done.Light source that used are He-Ne Laser 633 nm, green diode laser 532 nm and red diode laser 630 680 nm. He-Ne laser is used to calibrate the aperture wide, the value that found his used to determine green diode laser wavelength and red. The analysis of diffraction pattern by comparation the distance of each bright pattern to the center bright. From research was getting that using lens, diffraction pattern is progressively restrain from distance center brightness it experience enlargement,the distance rasio of bright patern is 1,43 : 2,30 : 3,16 : 4,06 : 5,00 , meanwhile diffraction without lens progressively goes away by its distance center experience narrowing and the distance rasio of bright patern is 1,50 : 2,43 : 3,32 : 4,26 : 5,12. Green diode laser its wavelength is (495 ± 4 ) nm and red diode laser wavelength is (659 ± 4 ) nm..