Optical module
The filter transmits a light beam of a second wavelength emitted from each of a plurality of second light sources, reflects other light beams incident from a direction intersecting a traveling direction of the light beam of the second wavelength, and outputs a combined light of the light beam of the second wavelength and the other light beams. The first optical element transmits part of the light beam of the first wavelength emitted from the first light source or part of the light beam of the second wavelength included in the combined light output from the filter, and reflects the other light beams excluding the part thereof in the direction intersecting the traveling direction. The first light receiving element receives the part of the light beam of the first wavelength transmitted by the first optical element or the part of the light beam of the second wavelength.
1. An optical module comprising:
a first light source that emits a light beam of a first wavelength according to a drive signal;
a plurality of second light sources that are arranged in parallel with the first light source, and emit light beams of second wavelengths according to a drive signal, the second wavelengths differing from each other;
a driver that supplies the drive signal to the first light source and to each of the plurality of second light sources; and
an optical combiner that combines the light beam of the first wavelength emitted from the first light source and the light beams of the second wavelengths emitted from the plurality of second light sources, wherein
the optical combiner includes:
a filter that is provided in each of the plurality of the second light sources, transmits a light beam of a second wavelength emitted from each of the plurality of second light sources, reflects other light beams incident from a direction intersecting a traveling direction of the light beam of the second wavelength, and outputs a combined light of the light beam of the second wavelength and the other light beams,
a first optical element that transmits part of the light beam of the first wavelength emitted from the first light source or part of the light beam of the second wavelength included in the combined light output from the filter, and reflects the other light beams excluding the part in the direction intersecting the traveling direction, and
a first light receiving element that receives the part of the light beam of the first wavelength transmitted by the first optical element or the part of the light beam of the second wavelength.
2. The optical module according to claim 1 , further comprising:
an optical fiber provided along a direction intersecting a traveling direction of a light beam of a second wavelength emitted from a terminal light source which is the farthest second light source from the first light source, of the plurality of second light sources, wherein
the first optical element corresponding to the filter provided in the terminal light source transmits part of the light beam of the second wavelength included in the combined light output from the filter, and reflects the combined light excluding the part to the optical fiber.
3. The optical module according to claim 1 wherein
the filter is not provided in a terminal light source which is the farthest second light source from the first light source, of the plurality of second light sources, and
the optical combiner further includes:
a second optical element that is provided in the terminal light source, reflects part of a light beam of a second wavelength emitted from the terminal light source, transmits the light beam of the second wavelength excluding the part, reflects the other light beams incident from the direction intersecting the traveling direction of the light beam of the second wavelength, and outputs a combined light of the light beam of the second wavelength and the other light beams, and
a second light receiving element that receives the part of the light beam of the second wavelength reflected by the second optical element.
4. The optical module according to claim 3 , further comprising:
an optical fiber provided along the traveling direction of the light beam of the second wavelength emitted from the terminal light source, wherein
the second optical element outputs the combined light to the optical fiber.
5. The optical module according to claim 1 , further comprising:
a first control unit that controls the drive signal supplied to the first light source and the second light source by the driver based on a difference between a value indicating the part of the light beam of the first wavelength received by the first light receiving element or indicating the part of the light beam of the second wavelength and a predetermined target value.
6. The optical module according to claim 3 , further comprising:
a first control unit that controls the drive signal supplied to the first light source and each of the plurality of second light sources excluding the terminal light source by the driver based on a difference between a value indicating the part of the light beam of the first wavelength received by the first light receiving element or indicating the part of the light beam of the second wavelength and a predetermined target value; and
a second control unit that controls the drive signal supplied to the terminal light source by the driver based on a difference between a value indicating the part of the light beam of the second wavelength received by the second light receiving element and the target value.