An optical communications method and an optical communications apparatus are provided. The method is executed on a communications node that includes an input optical modulator array and an output optical modulator array. The input optical modulator array includes N input optical modulators. The method includes determining at least two local input areas from the input optical modulator array, so that each input optical modulator in each local input area is used to receive a foreign signal light. The method also includes determining at least two local output areas from the output optical modulator array. Each output optical modulator in each local output area is used to send the foreign signal light, and each input optical modulator in a local input area is capable of transmitting the signal light to each output optical modulator in a corresponding local output area.