A system is disclosed which includes a laser which has a calibrated optical power and a calibrated tolerance. The system includes a driving circuit configured to generate a first current pulse and a second current pulse. The system includes a primary observer module configured to observe a first and second primary input. The system includes one or more secondary observer modules configured to observe one or more first and one or more second secondary inputs. The system includes a controller communicatively coupled to the laser, driving circuit, primary observer module, and the one or more secondary observer modules. The controller is configured to receive an information packet, calculate an optical power, determine a deviation of the optical power from the calibrated optical power, compare the deviation with the calibrated tolerance, and perform an action if the deviation exceeds the calibrated tolerance.

An apparatus includes a light source operable to produce light having a wavelength, an optical component disposed over the light source so as to intersect a path of light produced by the light source, and at least one electrically conductive trace on a surface of the optical component. A drive controller is operable to regulate optical output power of the light source. The at least one electrically conductive trace is coupled electrically to the drive controller, which is operable to monitor an electrical characteristic of the at least one electrically conductive trace, and to reduce the optical output power of the light source if a value of the electrical characteristic is indicative of a possible eye-safety hazard.

An object of the present invention is to reduce errors caused by changes in delay time when driving a light-emitting element. A light-emission driving device (10) includes: a light-emission current detection unit (401) (12); a phase difference detection unit (300); and a delay unit (200). The light-emission current detection unit (401) (12) detects a light-emission current for causing a light-emitting element (20) to emit light, the light-emission current being supplied from a light-emission driving unit (110). The phase difference detection unit (300) detects a phase difference between the detected light-emission current and a drive signal for controlling the supply of the light-emission current in the light-emission driving unit (110). The delay unit (200) adjusts propagation delay of the drive signal in accordance with the detected phase difference, and supplies the adjusted drive signal to the light-emission driving unit (110) as a drive signal. The present invention can be applied to a light-emitting device of a camera, for example.

A laser beam generation device includes power supply units, LD modules, a combiner, and a control device. The LD modules receive currents from the power supply units, and output laser beams. The combiner collects the laser beams and outputs one laser beam. The control device generates control signals such that power of the laser beam becomes a laser output setting value and such that the currents become current command values. Phases of pulses of the control signals are shifted from each other by 60 degrees.

A data transmission method including the step of controlling excitation current for a laser diode of a laser beam emitter device by servocontrolling the excitation current on laser beam power and by modulating the excitation current as a function of the data for transmission in order to encode the data with laser beam power levels, the method being characterized in that it includes the step of measuring a temperature (T.sub.INT) in the vicinity of the laser diode in order to perform, in accordance with the invention, two modes of operation having different setpoint values.

In a light-emitting device according to a first aspect of the present invention, a condenser is configured to smooth an output voltage of a switching power source. A voltage source of the light-emitting device is configured to adjust a voltage of the condenser. A processor of the light-emitting device is configured to turn on a light-emitting element of the light-emitting device. The processor is configured to measure the output voltage in a turning-on period of the light-emitting element and store the measured output voltage on the storage medium as a reference voltage. The processor is configured to turn off the light emitting element. The processor is configured to control a voltage output from the voltage source on the basis of the reference voltage stored on the storage medium so as to adjust the voltage of the condenser immediately before the light-emitting element is next turned on.

A pulsed laser diode driver includes an inductor having a first terminal configured to receive a source voltage. A source capacitor has a first terminal connected to the first terminal of the inductor to provide the source voltage. A bypass switch has a drain node connected to a second terminal of the inductor and to a first terminal of a bypass capacitor. A laser diode switch has a drain node connected to the second terminal of the inductor. A laser diode has an anode connected to a source node of the laser diode switch and a cathode connected to a bias voltage node. The laser diode switch and the bypass switch control a current flow through the inductor to produce a high-current pulse through the laser diode, the high-current pulse corresponding to a peak current of a resonant waveform developed at the anode of the laser diode.

A system is provided for maintaining a safe operating area while also providing a suitable forward bias voltage to drive a laser diode. The system can monitor a voltage that is applied to a laser diode driver using a threshold that is based on the fabrication process of the laser diode driver. For example, a system can utilize a first threshold for a laser diode driver that is fabricated utilizing a 10 nm process and utilize a second threshold for another laser diode driver that is fabricated utilizing a 20 nm process. The threshold can also be based on a color of the laser or a desired operation mode. The system can monitor a voltage applied to a laser diode using different thresholds while controlling a bleed current to ensure that the laser diode is forward biased while mitigating the risk of silicon breakdown of the laser diode driver.

A driving and stabilization system for a pump laser, and a pump laser system. The driving and stabilization system includes a constant current stabilization device, a constant temperature stabilization device, a power detection device, an environment detection device, and a control device. The constant current stabilization device includes a voltage comparison circuit, a constant current driving circuit, and a switch protection circuit. The constant temperature stabilization device includes an internal constant temperature stabilization circuit and an external constant temperature stabilization circuit.

A control device for controlling two or more laser diode (LD) modules each supplying pumping light to a variable-output fiber laser, includes: a controller that sets, in accordance with a set value of laser output power of the variable-output fiber laser, a number of LD modules to which a driving current is supplied among the two or more LD modules.