Edge filter has been widely used in fiber grating sensing systems and the principle is to convert the wavelength offset into the change of optical power, which has the advantages of fast response and large dynamic detection range. In order to achieve a periodic edge filter named low-loss jammed-array sawtooth (JAWS) filter, a finite reflection virtually imaged array (FRVIA) is proposed and demonstrated. Comparing with virtually imaged phased array (VIPA), FRVIA has a low reflectivity in the back side, with the differences of output light intensity distribution, spectral resolution and output aperture and so on. By numerical simulation, the parameters of the low-loss JAWS filter have been optimized, a low-loss JAWS filter has be achieved with up to 70% duty cycle and lower than 14 dB loss.