As shown in FIG. 6B and FIG. 6C, the LED filament 100 surrounds with the wave shape resembling to a circle and has a quasi-symmetric structure in the top view, and the lighting face of the LED filament 100 is also symmetric, e.g., the main lighting face Lm in the top view may faces outwardly; therefore, the LED filament 100 may generate an effect of an omnidirectional light due to a symmetry characteristic with respect to the quasi-symmetric structure of the LED filament 100 and the arrangement of the lighting face of the LED filament 100 in the top view. Whereby, the LED light bulb 20c as a whole may generate an effect of an omnidirectional light close to a 360 degrees illumination. Additionally, the two joint points may be close to each other such that the conductive supports 51a, 51b are substantially below the LED filament 100. Visually, the conductive supports 51a, 51b keeps a low profile and is integrated with the LED filament 100 to show an elegance curvature.
