A Laser device for optical packet data transmission in TDM-systems is provided. The device comprises a laser light source for outputting laser light beam and a laser driver for driving the laser light source; an optical modulator which receives and modulates the laser light beam output by the laser light source; a packet data source for outputting a packet data stream; and a modulator driver for receiving the packet data stream output by the packet data source and for driving the optical modulator in response to the packet data stream resulting in that the optical modulator modulates the laser light beam in response to the packet data stream. A filter generates an envelope signal of the data packets in the packet data stream, and a switch switches the laser driver in response to the envelope signal.