Optical light splitter, preparation method thereof, image sensor and image imaging system

The present invention provides an optical light splitter, a preparation method thereof, an image sensor and an image imaging system. The optical light splitter is an array structure formed by arranging a plurality of light splitting units on a substrate in a one-dimensional manner, and each light splitting unit comprises an upper reflection layer, a lower reflection layer and a dielectric layer located between the upper and lower reflection layers. The lower reflection layer is a horizontal plane structure, and the upper reflection layer is an inclined plane structure or a curved surface structure. The optical light splitter, the preparation method thereof, the image sensor and the image imaging system provided by the present invention are simultaneously high in integration degree, small in size and short in hyperspectral imaging time consumption.