An optical measurement device configured for connection to an industrial network, the industrial network functioning to synchronize time between a master device and a slave device, the optical measurement device includes: an interface module configured to receive a synchronization signal transmitted on the industrial network from the master device within a fixed communication cycle; and a measurement unit configured to perform optical measurements in a measurement cycle. The measurement unit synchronizes when a measurement is taken with the communication cycle in accordance with the synchronization signal received by the interface module.