This paper proposes a novel Non-linear Camera Assisted-Received Signal Strength (nCA-RSS) algorithm. The basic idea of nCA-RSS is to simultaneously utilize camera and Photo-Diode (PD) to capture visual information and signal strength information to achieve both high coverage and accurate positioning. First, based on single-view geometry theorem, nCA-RSS algorithm estimates incidence angle of visible light based on visual information. Then, based on the estimated incidence angle, nCA-RSS algorithm utilizes signal strength to determine the location of the receiver. Due to the use of visual information, nCA-RSS no longer has orientation limitations. Based on Levenberg-Marquardt, nCA-RSS can use three Light Emitting Diode (LED) to achieve precise 3-Dimensional (3D) positioning. Therefore, compared with perspective n point algorithm, nCA-RSS can achieve high coverage. Simulation results show that nCA-RSS can achieve 80^th percentile accuracies of less than 2.5 cm for positioning regardless of the orientation of the receiver.