Laser Side Mode Suppression Ratio (SMSR) control is provided via a logic controller configured to measure an SMSR of a carrier wave upstream of a modulator and measure an Average Optical Power (AOP) of the carrier wave downstream of the modulator; transmit a bias voltage based on the SMSR and the AOP to a laser driver for a laser generating the carrier wave; and transmit an attenuation level based on the SMSR and the AOP to a Variable Optical Attenuator (VOA) upstream of the modulator. In various embodiments the attenuation level and bias voltage can rise or fall together, or one may rise and one may fall to ensure the output optical signal meets specified SMSR and AOP values.

Laser Side Mode Suppression Ratio (SMSR) control is provided via a logic controller configured to measure an SMSR of a carrier wave upstream of a modulator and measure an Average Optical Power (AOP) of the carrier wave downstream of the modulator; transmit a bias voltage based on the SMSR and the AOP to a laser driver for a laser generating the carrier wave; and transmit an attenuation level based on the SMSR and the AOP to a Variable Optical Attenuator (VOA) upstream of the modulator. In various embodiments the attenuation level and bias voltage can rise or fall together, or one may rise and one may fall to ensure the output optical signal meets specified SMSR and AOP values.

A laser device is provided. The laser device includes a case, a plurality of light-emitting assemblies, an upper cover assembly and a stress-offsetting structure. The case includes a bottom plate and a frame body. The frame body is disposed on the bottom plate, and is enclosed on the bottom plate to form an accommodating space with an opening. The plurality of light-emitting assemblies is located in the accommodating space and are disposed on the bottom plate. The upper cover assembly is fixed to the case and covers the opening. The stress-offsetting structure is disposed in the frame body and/or in the upper cover assembly, and is configured to be contracted in a squeezing direction when the stress-offsetting structure is squeezed.

An optical member includes: a conversion member including a fluorescent material; a light reflecting ceramic holding the conversion member, the conversion member and the light reflecting ceramic having a continuous surface; a light-transmissive film on the continuous surface; and a wiring on the light-transmissive film.

A light-emitting device includes: a base including: a mount surface, and a lateral wall located around the mount surface, the lateral wall including: a pair of first protrusions located opposite to each other in a first direction which is parallel to a side of the mount surface, and a pair of second protrusions located opposite to each other in a second direction which is perpendicular to the first direction, the second protrusions being provided lower than the first protrusions; one or more light-emitting elements mounted on the mount surface of the base; a first light-transmissive member sealing a space in which the one or more light-emitting elements are mounted; and one or more wires connecting to the one or more light-emitting elements, the one or more wires being bonded on conduction regions provided on at least one of upper surfaces of the second protrusions.

A light-emitting device includes: a base including: a mount surface, and a lateral wall located around the mount surface, the lateral wall including: a pair of first protrusions located opposite to each other in a first direction which is parallel to a side of the mount surface, and a pair of second protrusions located opposite to each other in a second direction which is perpendicular to the first direction, the second protrusions being provided lower than the first protrusions; one or more light-emitting elements mounted on the mount surface of the base; a first light-transmissive member sealing a space in which the one or more light-emitting elements are mounted; and one or more wires connecting to the one or more light-emitting elements, the one or more wires being bonded on conduction regions provided on at least one of upper surfaces of the second protrusions.

A semiconductor laser device includes: a support base having a plurality of mounting surfaces arranged in a first direction, wherein heights of the mounting surfaces from a reference plane that is parallel to the first direction decrease stepwise or gradually along the first direction; a first semiconductor laser element secured to a first mounting surface; a second semiconductor laser element secured to a second mounting surface; a first slow-axis collimator lens secured to the first mounting surface, the first slow-axis collimator lens being located at a position at which the first laser light is incident; a second slow-axis collimator lens directly or indirectly secured to the second mounting surface, the second slow-axis collimator lens being located at a position at which the second laser light is incident; and a first sealing cover that defines an inner space in which the first and second semiconductor laser elements are held.

A light source device includes: a laser diode; a substrate directly or indirectly supporting the laser diode; and a cap secured to the substrate and covering the laser diode. The cap includes a first glass portion configured to transmit laser light that is emitted from the laser diode, and a second glass portion. At least one of the first glass portion and the second glass portion includes an alkaline glass region. The first glass portion and the second glass portion are bonded together via an electrically conductive layer that is in contact with the alkaline glass region.

A light source device includes: a laser diode; a substrate directly or indirectly supporting the laser diode; and a cap secured to the substrate and covering the laser diode. The cap includes a first glass portion configured to transmit laser light that is emitted from the laser diode, and a second glass portion. At least one of the first glass portion and the second glass portion includes an alkaline glass region. The first glass portion and the second glass portion are bonded together via an electrically conductive layer that is in contact with the alkaline glass region.

A light-emitting device includes a base structure, a light-emitting element, an optical member, and first and second adhesive parts. The first adhesive parts are disposed in first and second regions of a second surface of the base structure. The second adhesive parts are located at both opposite sides of the first adhesive part without being in contact with the first adhesive part. In the top view, a virtual first line segment, which connects two points respectively on the first adhesive parts in the first and second regions, extends across a first surface of the base structure. A virtual line segment, which connects two points respectively on the second adhesive parts at the both opposite sides of the first adhesive part, does not extend across the first surface. A width of the first adhesive part along the line segment is greater than a width of the second adhesive part.