The large angle deflection of light causes such problems as the high Fresnel loss and the poor luminous intensity uniformity. To solve these problems, a design algorithm of double freeform surface lens, which is based on the optimal double deflection energy mapping and the multi-parameter optimized Bézier curve, is proposed. Guided by this algorithm, a double freeform surface lens based on the light emitting diode (LED) of chip on broad (COB) is proposed, and it can be used for the optical transmitting end of visible light communication systems. To reduce the Fresnel loss, we use the large-emission area COB LED as light source, and control the ratio of incident light deflection angles of freeform surface lens’s inner and outer surfaces. Double freeform surface lenses, with large angle uniform luminous intensity distribution and with irritation angles of 180° and 260° respectively, are constructed. The luminous intensity uniformity of the lenses reaches up to 0.92 and 0.90 respectively, and the light utilization efficiency of the lenses reaches up to 89.4% and 85.9% respectively. The optical properties of the single freeform surface lens and the double freeform surface lens are compared. For the single freeform surface lens, light distribution with high luminous intensity uniformity over 0.85 and high light utilization efficiency over 0.85 can be achieved when the irritation angle varies in the range from 120° to 180°. For the double freeform lens with the same luminous intensity uniformity and light utilization efficiency, the irritation angle varies in a broader range from 100° to 260°. This study indicates that the double freeform surface lens can realize uniform light intensity distribution with broad irritation angle, and it can satisfy the light distribution requirements of optical transmitting end in visible light communication systems.