Patent ID: 8331787
Filing Date: 2012-12-11
Classification: H04J

Abstract:
1. An optical transmitting apparatus, comprising: a variable optical attenuator that transits to a first state when a level of output light of the variable optical attenuator exceeds a first threshold, and transits to a second state when the level of output light falls below a second threshold which is higher than the first threshold, an attenuation amount of the variable optical attenuator being controlled to vary according to feedback control in the first state and to be constant in the second state; a determining unit that determines, during a protection period, whether a level of output light from the variable optical attenuator falls below the first threshold, the protection period being a predetermined time period after the variable optical attenuator transits from the second state to the first state during which state transition is prohibited; and a control unit that controls the variable optical attenuator to transit from the first state to the second state when determining that the level of the output light falls below the first threshold.