This invention provides an optical transmitter module and an optical module using an EA modulator capable of realizing stable ACER regardless of operating temperature without using a control mechanism for maintaining temperature of the EA modulator constant. In the EA modulator, optical waveguides formed of a multi-layered film are formed on a substrate, an electrical signal is applied to the optical waveguides in a direction vertical to the substrate, and the input light absorption amount is changed to control the amount of output light. Also, a plurality of p-side electrodes electrically separated from each other for applying an electrical signal to the active layer optical waveguides are arranged on optical axes of active layer optical waveguides. The length of optical waveguides to which the electrical signal is applied is changed by controlling the number of p-side electrodes to which the electrical signal is applied in accordance with temperature.
This invention provides an optical transmitter module and an optical module using an EA modulator capable of realizing stable ACER regardless of operating temperature without using a control mechanism for maintaining temperature of the EA modulator constant. In the EA modulator, optical waveguides formed of a multi-layered film are formed on a substrate, an electrical signal is applied to the optical waveguides in a direction vertical to the substrate, and the input light absorption amount is changed to control the amount of output light. Also, a plurality of p-side electrodes electrically separated from each other for applying an electrical signal to the active layer optical waveguides are arranged on optical axes of active layer optical waveguides. The length of optical waveguides to which the electrical signal is applied is changed by controlling the number of p-side electrodes to which the electrical signal is applied in accordance with temperature.
This invention provides an optical transmitter module and an optical module using an EA modulator capable of realizing stable ACER regardless of operating temperature without using a control mechanism for maintaining temperature of the EA modulator constant. In the EA modulator, optical waveguides formed of a multi-layered film are formed on a substrate, an electrical signal is applied to the optical waveguides in a direction vertical to the substrate, and the input light absorption amount is changed to control the amount of output light. Also, a plurality of p-side electrodes electrically separated from each other for applying an electrical signal to the active layer optical waveguides are arranged on optical axes of active layer optical waveguides. The length of optical waveguides to which the electrical signal is applied is changed by controlling the number of p-side electrodes to which the electrical signal is applied in accordance with temperature.
For achieving a transmission light source having different transmission properties or characteristics, i.e., the .alpha. parameters, depending upon application thereof, in a light emission element of semiconductor EA modulator integrated type being constructed with a light emission portion for lasing with a single vertical mode and a plurality of EA modulators, wherein an absorption edge wavelength under the condition of applying no bias thereto, in the semiconductor multiple-quantum-well structure owned by the modulator which is near to an emission side of the light emission portion, is to be equal or longer than the absorption edge wavelength owned by the modulator positioned far from the emission side of the light emission portion.
For achieving a transmission light source having different transmission properties or characteristics, i.e., the a parameters, depending upon application thereof, in a light emission element of semiconductor EA modulator integrated type being constructed with a light emission portion for lasing with a single vertical mode and a plurality of EA modulators, wherein an absorption edge wavelength under the condition of applying no bias thereto, in the semiconductor multiple-quantum-well structure owned by the modulator which is near to an emission side of the light emission portion, is to be equal or longer than the absorption edge wavelength owned by the modulator positioned far from the emission side of the light emission portion.