A laser driver for driving a Vertical Cavity Surface Emitting Laser (VCSEL) includes a high-side switch (High-side Field Effect Transistor) having an internal capacitor for charging with a drain terminal thereof connected to a high-voltage terminal, a low-side switch (Low-side Field Effect Transistor) in which a drain terminal thereof is connected to a source terminal of the high-side switch and a source terminal thereof is connected to a ground terminal, and a VCSEL diode having an anode terminal connected to the high-side switch.

A pulsed laser diode driver includes a refresh circuit configured to generate a refresh current using a received input voltage. A current amplitude of the refresh current is controlled by the refresh circuit based on a voltage level of a source voltage received by the refresh circuit. A source capacitor of the pulsed laser diode driver is configured to receive the refresh current and to develop the source voltage therefrom. An inductor of the pulsed laser diode driver has a first terminal that is directly electrically connected to the source capacitor. One or more switches of the pulsed laser diode driver are configured to control a current flow through the inductor to produce a high-current pulse through a laser diode that corresponds to a peak current of a resonant waveform developed at an anode of the laser diode.

A light emitting device includes a substrate, a light emitting element, a driving element, and a capacitor layer. The light emitting element and the driving element are provided on the substrate. The driving element drives the light emitting element. The capacitor layer is provided in the substrate and supplies electric current to the light emitting element via the driving element.

A photonic crystal surface-emitting laser includes a light emitting module and a driving module. The light emitting module includes a photonic crystal layer, an active light emitting layer on a side of the photonic crystal layer, a first electrode on a side of the active light emitting layer facing away from the photonic crystal layer, and a second electrode partially on the side of the active light emitting layer facing away from the photonic crystal layer. The driving module makes electrical contact with surfaces of the first electrode and the second electrode facing away from the photonic crystal layer. The driving module outputs driving signals to the first electrode and the second electrode to drive the active light emitting layer to generate photons. The photons are incident into the photonic crystal layer to generate a laser light through oscillation on Bragg diffraction. An optical system is also disclosed.

Disclosed is an optical semiconductor device including a semiconductor laser chip, an insulation substrate, a ground pattern, a mounted pattern, a resistor and an extension ground pattern. The insulation substrate has a surface mounting the semiconductor laser chip thereon. The ground pattern and the mounted pattern are provided on the surface. The mounted pattern has an opposite side opposite to the ground pattern. The resistor is disposed such that a side edge of the resistor separates from an extension region of the opposite side. The extension ground pattern is positioned in the extension region of the opposite side and is electrically connected to the ground pattern. The capacitor is disposed on the mounted pattern.

An input is coupled to a cathode of a laser diode having its anode coupled to a high-voltage-supply, with a cascoded current mirror having an input and output branches. The input branch is coupled between the high-voltage-supply and a sense resistor coupled to the input. The output branch is coupled between the high-voltage-supply and an output. A sense resistance is coupled between the output and ground, and includes a diode-coupled transistor coupled to the output and a resistor coupled between the diode-coupled transistor and ground. The input branch generates a current proportional to a voltage across the laser diode, and the output branch generates a mirrored current proportional to the current proportional to the voltage across the laser diode. A voltage proportional to the voltage across the laser diode is generated by the mirrored current flowing through the sense resistance. A comparison circuit compares this voltage to a threshold.

A vertical-cavity surface-emitting laser (VCSEL) has a substrate formed of GaAs. A pair of mirrors is provided wherein one of the pair of mirrors is formed on the substrate. A tunnel junction is formed between the pair of mirrors.

A light emitting device includes a first substrate, a light source on a first surface of the first substrate and that emits light toward an object, and a driver disposed in the first substrate and that drives the light source. The driver overlaps the light source in a plan view. The light emitting device includes at least one first via disposed in the first substrate and overlapping the driver in the plan view, and a first conductor on a second surface of the first substrate opposite the first surface and overlapping the light source, the driver, and the at least one first via in the plan view. The first conductor is connected to the at least one first via.

A wide-angle illuminator module including a rigid support structure having a plurality of angled faces, a flexible circuit including one or more VCSEL arrays, each VCSEL array positioned over a face among the plurality of angled faces, each VCSEL array including a plurality of integrated microlenses with one microlens positioned over each VCSEL in the VCSEL array, and a driver circuit for providing electrical pulses to each VCSEL array, wherein the plurality of VCSEL arrays address illumination zones in a combined field of illumination. The support structure may also be a heatsink. The flexible circuit may be a single flexible circuit configured to be placed over the support structure or a plurality of flexible circuits, each including one VCSEL array.

An object of the present technique is to obtain excellent heat radiation characteristics with a simple structure in a semiconductor laser driving apparatus. A semiconductor laser driving apparatus includes a substrate, a laser driver, and a semiconductor laser. The substrate incorporates the laser driver. The semiconductor laser is mounted on one surface of the substrate. Connection wiring electrically connects the laser driver and the semiconductor laser to each other with a wiring inductance of 0.5 nanohenries or less. Side walls surround a region including the semiconductor laser on the surface of the substrate where the semiconductor laser is mounted. The side walls have a heat storage material therein.