ABSTRACT In this paper, special long period fiber gratings with Gauss envelope and rotary refractive index modulations, as well as ultra long period fiber grating are fabricated by using the high frequency CO 2 laser pulses exposure method. The characteristics of these LPFGs are investigated by experiment. It is anticipated that these novel LPFGs would find potential applications in optical fiber sensing and optical fiber communication due to their special optical waveguide structure. Keywords: fiber-optic components, long period fiber grating, optical fiber sensing, optical fiber communication. 1. INTRODUCTION Long period fiber gratings (LPFGs) have periodic refractive index perturbations along the length of an optical fiber that couple the fundamental mode to the cladding modes [1]. Compared with other methods of fabricating LPFGs, such as the UV exposure method, the high-frequency CO 2 laser pulses exposure method reported previously by the authors [2] has a number of advantages, such as much lower cost due to the use of standard telecommunication fiber and relatively expensive CO