A composite module includes a macro focus module comprising a second lens and at least one light source near the second lens, wherein the second lens is movable, after the time that the second lens moves to a predetermined location in front of the first lens, the light source illuminates, and after the time that the second lens leaves the predetermined location of the first lens, the light source extinguishes; a power supply module comprising a power supply and a connection interface; and a first circuit board coupled to the power supply, the light source and the connection interface, wherein the power supply is configured to provide power for the light source, and further provide power for the mobile phone through the connection interface which is connected to the mobile phone.