Patent ID: 7366215

Claim:
An optical module comprising: a stem; a first lead pin and a second lead pin for receiving differential signals, the first and second lead pins penetrating the stem; a mount block fixed to the stem; a laser diode having a pair of electrodes, the laser diode having a resistance; a submount mounted on the mount block and having a matching resistance, an interdigital capacitor, and a plurality of electrode patterns on a surface of the submount; and a first wire and a second wire electrically connecting the submount to the first and second lead pins, respectively, wherein the laser diode is mounted on a first of the plurality of electrode patterns on the submount and connected to a second of the plurality of electrode patterns on the submount by a third wire such that the laser diode, together with the matching resistance and the interdigital capacitor, forms an electrical circuit, the matching resistance has a value smaller than an impedance value obtained by subtracting the resistance of the laser diode from impedance of a differential signal source supplying the differential signals, and the interdigital capacitor having a capacitance selected to reduce signal reflection at a selected frequency.