This work provides a survey of illumination sources versus application requirements for some common 3D imaging approaches. Sources for FMCW, pulsed, and flash LiDAR, in applications such as autonomous driving, face recognition, and underwater imaging are discussed. The requirements and restrictions for each application are considered, including power, maximum range, field of view, and eye safety. In the context of these application requirements and restrictions, source characteristics such as coherence length, average power, peak power, bandwidth, and timing characteristics are used to evaluate the suitability of each source. This multidimensional survey attempts to provide a matrix with suitable sources for time of flight (ToF), frequency modulated continuous wave (FMCW) and flash lidar systems for various applications.