A reduced size of camera module includes a camera lens, an optical filter, a sensor, an optical filter trestle, and a module trestle. The camera lens lies on a light path of the camera module towards the sensor. The camera lens is mounted on the optical filter trestle. The optical filter is received is the optical filter trestle. The optical filter trestle is mounted on the module trestle. The sensor is received in the in the module trestle.