Patent ID: 8634721

Claim:
An optical communication method comprising: transmitting an optical data signal to a predetermined receiver, wherein the optical data signal includes a data area and a non-data area, data signals exist in the data area, the non-data area is an area other than the data area and precedes the data area, and a signal amplitude of the non-data area is made higher than a signal amplitude of the data area; receiving an optical input including the optical data signal transmitted in the transmitting, with the predetermined receiver; detecting each of the signal amplitude of the non-data area and the signal amplitude of the data area of the optical input received in the receiving; creating a threshold for encoding the data area based on the signal amplitude of the data area detected in the detecting; determining whether the optical data signal is received, based on the signal amplitude of the non-data area detected in the detecting; and outputting a data signal in which the data area is encoded by using the threshold of the optical data signal created in the creating, when it is determined in the determining that the optical data signal is received.