Abstract: An optical module for transmitting an optical signal may include a circuit board on which electronic components are disposed, a high-frequency component that is disposed on a main surface of the circuit board and operates at a frequency equal to or higher than a predetermined reference value according to a frequency of the optical signal, a low-frequency component that is disposed on another main surface of the circuit board so as to overlap at least partly with the high-frequency component in a plan view and operates at a frequency less than the reference value, and an electromagnetic wave absorber that is disposed on an upper surface of the low-frequency component.

Abstract: An optical module for transmitting an optical signal may include a circuit board on which electronic components are disposed, a high-frequency component that is disposed on a main surface of the circuit board and operates at a frequency equal to or higher than a predetermined reference value according to a frequency of the optical signal, a low-frequency component that is disposed on another main surface of the circuit board so as to overlap at least partly with the high-frequency component in a plan view and operates at a frequency less than the reference value, and an electromagnetic wave absorber that is disposed on an upper surface of the low-frequency component.

Abstract: A first conductive layer includes a first signal wiring including, at a position except for an end portion, a wide portion having a width wider than that of the other portion. A second conductive layer includes a signal electrode electrically continuous with the end portion of the first signal wiring, a first ground plane overlapping the wide portion, and a ground terminal. A third conductive layer includes a second signal wiring including an end portion overlapping and bonded to the signal electrode, and a ground electrode overlapping and bonded to the ground terminal. A fourth conductive layer includes a second ground plane. The second ground plane includes a through hole overlapping the end portion of the second signal wiring. A fifth conductive layer includes a third groundplane. The third groundplane overlaps the end portion of the second signal wiring inside the through hole.

Abstract: A first conductive layer includes a first signal wiring including, at a position except for an end portion, a wide portion having a width wider than that of the other portion. A second conductive layer includes a signal electrode electrically continuous with the end portion of the first signal wiring, a first ground plane overlapping the wide portion, and a ground terminal. A third conductive layer includes a second signal wiring including an end portion overlapping and bonded to the signal electrode, and a ground electrode overlapping and bonded to the ground terminal. A fourth conductive layer includes a second ground plane. The second ground plane includes a through hole overlapping the end portion of the second signal wiring. A fifth conductive layer includes a third groundplane. The third groundplane overlaps the end portion of the second signal wiring inside the through hole.

Abstract: Provided is an optical module in which a temperature of a semiconductor element to be subjected to temperature control is controlled to fall within a desired operating temperature range regardless of whether an environmental temperature is outside or inside the operating temperature range of the semiconductor element, and which is stably operated with low power consumption. A control section 30 determines, based on the environmental temperature having a temperature range of from a first temperature to a second temperature, a target temperature from a predetermined operating temperature range of from a third temperature to a fourth temperature. The control unit 30, an ATC circuit 34, a TEC control IC 12, and a TEC 24 control the temperature of a laser module 20 to become the target temperature. The first temperature is lower than the third temperature, and the second temperature is higher than the fourth temperature.

Abstract: Provided is an optical module in which a temperature of a semiconductor element to be subjected to temperature control is controlled to fall within a desired operating temperature range regardless of whether an environmental temperature is outside or inside the operating temperature range of the semiconductor element, and which is stably operated with low power consumption. A control section 30 determines, based on the environmental temperature having a temperature range of from a first temperature to a second temperature, a target temperature from a predetermined operating temperature range of from a third temperature to a fourth temperature. The control unit 30, an ATC circuit 34, a TEC control IC 12, and a TEC 24 control the temperature of a laser module 20 to become the target temperature. The first temperature is lower than the third temperature, and the second temperature is higher than the fourth temperature.