A light source includes a substrate with a first surface and an opposite second surface. An epitaxial layer is positioned on the first surface of the substrate. The light source also includes at least one light generator in the epitaxial layer positioned such that an optical signal transmitted thereby is directed toward the substrate. A diffuser is positioned on the second surface of the substrate, and at least one monitor photodetector is positioned in the epitaxial layer in an arrangement configured to receive a portion of the optical signal which is reflected by the diffuser. In one form, the light generator may include a vertical cavity surface emitting laser (VCSEL).

A light-emitting device includes: a base including a mount surface, and a lateral wall located around the mount surface, the lateral wall having a first upper surface and a second upper surface located at different heights from the mount surface; one or more light-emitting elements mounted on the mount surface of the base; a light-receiving element configured to receive a portion of light emitted from the one or more light-emitting elements; a first light-transmissive member bonded to the first upper surface and sealing a space in which the light-emitting elements are mounted; and a second light-transmissive member bonded to the second upper surface and supporting the light-receiving element.

A photodetector is positioned so that imaginary lines perpendicular to an emission end surface of a first light-emitting element through first and second points, respectively, pass through the photodetector. The first and second points are two points at which an imaginary line parallel to the emission end surface through an inside of an outer edge of the first light-emitting element intersects the outer edge of the first light-emitting element in a top view. At least a part of a first wiring region is arranged in a first region between imaginary lines perpendicular to the emission end surface through third and fourth points, respectively. The third and fourth points are two points at which an imaginary line parallel to the emission end surface through an inside of an outer edge of the photodetector intersects the outer edge of the photodetector in the top view.

Methods for driving a tunable laser with integrated tuning elements are disclosed. The methods can include modulating the tuning current and laser injection current such that the laser emission wavelength and output power are independently controllable. In some examples, the tuning current and laser injection current are modulated simultaneously and a wider tuning range can result. In some examples, one or both of these currents is sinusoidally modulated. In some examples, a constant output power can be achieved while tuning the emission wavelength. In some examples, the output power and tuning can follow a linear relationship. In some examples, injection current and tuning element drive waveforms necessary to achieve targeted output power and tuning waveforms can be achieved through optimization based on goodness of fit values between the targeted and actual output power and tuning waveforms.

Methods for driving a tunable laser with integrated tuning elements are disclosed. The methods can include modulating the tuning current and laser injection current such that the laser emission wavelength and output power are independently controllable. In some examples, the tuning current and laser injection current are modulated simultaneously and a wider tuning range can result. In some examples, one or both of these currents is sinusoidally modulated. In some examples, a constant output power can be achieved while tuning the emission wavelength. In some examples, the output power and tuning can follow a linear relationship. In some examples, injection current and tuning element drive waveforms necessary to achieve targeted output power and tuning waveforms can be achieved through optimization based on goodness of fit values between the targeted and actual output power and tuning waveforms.

Provided are a subminiature optical transmission module and a method for manufacturing same. The optical transmission module includes: a mold body having a first surface and a second surface opposite to each other; multiple edge-type light emitting elements, each of which is molded inside the mold body by fitting same to the first surface so as to match with the first surface and generates an optical signal in the edge direction of a chip; and an optical component disposed on one side thereof so as to optically multiplex multiple optical signals incident from the multiple edge-type light emitting elements and to output same, wherein the identical height is configured between the surface of each light emitting element and the optical axis of the optical component, and the edge direction of the chip is parallel to the first surface of the mold body.

The present invention provides methods and an apparatus for monitoring the optical output power of a laser diode (LD) having an associated photodiode (PD), and a particle sensor apparatus. The photodiode (PD) is operable together with the laser diode (LD), wherein it detects the light (LS) of the laser diode (LD) and converts it into an electrical current, and is thermally coupled to the laser diode (LD). Monitoring of the optical output power P is effected during the operation of the laser diode (LD) and is based on current measurements and/or voltage measurements at the laser diode (LD) and at the photodiode (PD).

The present invention provides methods and an apparatus for monitoring the optical output power of a laser diode (LD) having an associated photodiode (PD), and a particle sensor apparatus. The photodiode (PD) is operable together with the laser diode (LD), wherein it detects the light (LS) of the laser diode (LD) and converts it into an electrical current, and is thermally coupled to the laser diode (LD). Monitoring of the optical output power P is effected during the operation of the laser diode (LD) and is based on current measurements and/or voltage measurements at the laser diode (LD) and at the photodiode (PD).

A device for managing power of a laser source in a laser-based apparatus includes switched-mode power controller circuitry. The power controller circuitry further includes a controller output configured to be coupled to reservoir capacitor of a laser source to provide a first mode of regulating charging of the reservoir capacitor between illuminations of the laser source and a second mode of regulating charging of the reservoir capacitor during illuminations of the laser source.

A device for managing power of a laser source in a laser-based apparatus includes switched-mode power controller circuitry. The power controller circuitry further includes a controller output configured to be coupled to reservoir capacitor of a laser source to provide a first mode of regulating charging of the reservoir capacitor between illuminations of the laser source and a second mode of regulating charging of the reservoir capacitor during illuminations of the laser source.