The invention relates to a method of inner light layer illumination for optical imaging and detection in turbid media and apparatuses designed based on this method. This invention uses multiple beam interference to create destructive interference in the propagation path to reduce the illumination beam intensity and so to reduce absorption and scattering of the turbid media, and to create constructive interference to produce composite light intensity maximum which forms an inner light layer to illuminate the object. The theoretical analyses and mathematical calculations have proved the feasibility of the method. The designed apparatuses have great performances. Compared with the traditional technology, this method can enhance the signal strength more than 600 dB. The imaging depth can be over 5 cm in human body, and more than 500 m in clear seawater. The imaging resolutions are