A multi-gear brightness adjustment circuit board, and a multi-gear battery holder structure, which through adding the automatic control gear AUTO conductive contact piece and a light spot dot-circle pattern composite conductive contact piece on the circuit board, the gear can be automatically adjusted when the solar cell is used for power supply. Ensuring that the output light power meets the needs of ambient light, rationally use electric energy, which is conducive to energy saving; at the same time, the mode switching of the shooting target is integrated, which reduces the parts of the sight and makes the sight more compact.