A tunable optical comb generator having a source laser configured to generate a continuous wave (CW) light at a first wavelength; and a microresonator coupled to the source laser and configured to receive the CW light and generate an optical signal having a plurality of output wavelengths corresponding to the first wavelength. The generator includes a microresonator tuning device coupled to the microresonator and configured to tune the microresonator to compensate the microresonator for wavelength shifts. A control circuit is coupled to the microresonator tuning device and configured to generate a control signal to control the microresonator tuning device based on the optical signal. Multiple microresonators in the form of microrings may be included to tune the generator. A heater coupled to the microresonators may be used to adjust the microresonators.

A burst logging system logs and transmits to a local or remote computing system event data related to errors in and or potential failures of laser system components. The system further provides for capturing data at different rates from different sensors, synchronization of data capture associated with system events and the possibility for aggregation of data from multiple systems, which can in turn be leveraged to predict and or remediate future system events.

An optical amplifier is provided in which radiation levels experienced by an optical fiber are minimized. A sealed enclosure houses an optical fiber. An input optical signal enters on end of the fiber and an amplified output optical signal exits the other end of the optical fiber. Small particles embedded with a gas fill the interior of the enclosure. An optical pump supplies an amplification laser beam coupled to one of the ends of the optical fiber. Due to energy supplied by the amplification laser beam, the input optical signal is amplified upon exiting the optical fiber. At least a portion of the gas embedded in the small particles is released inside the enclosure when the small particles are subjected to heat to provide a gaseous interior in the enclosure that minimizes radiation levels experienced by the optical fiber due to external radiation.

The conjugated polymer laser with temperature-controlled power output uses a triphenylamine dimer-based conjugated polymer as the laser medium to produce an output laser beam having a beam energy tunable between approximately 20 J and approximately 325 J over a temperature range of the triphenylamine dimer-based conjugated polymer between approximately 40 C. and approximately 85 C. The triphenylamine dimer-based conjugated polymer laser medium is a solution of poly[N,N-bis(4-butylphenyl)-N,N-bisphenylbenzidine], known as poly-TPD(4B), dissolved in toluene. Poly-TPD(4B) has a long side chain of butyl (C.sub.4H.sub.9), providing temperature-dependent dimerization, which may not be found with shorter chains of butyl, such as in poly-TPD(4E) or poly-TPD(4M). The molar concentration of the poly-TPD in the solution is between approximately 5 M and approximately 100 M. Additional adjustable tuning of the molar concentration of the poly-TPD in the solution provides for wavelength tuning of the output laser beam between approximately 415 nm and approximately 445 nm.

Direct diode-pumped Ti:sapphire laser amplifiers use fiber-coupled laser diodes as pump beam sources. The pump beam may be polarized or non-polarized. Light at wavelengths below 527 nm may be used in cryogenic configurations. Multiple diode outputs may be polarization or spectrally combined.

A laser oscillator having a condensation prevention mechanism capable of extending the life span of a light emitting device while maintaining cost effectiveness as compared to the conventional technique is provided. The laser oscillator includes: a laser beam generating unit; a heat exchanger; a coolant bypass circuit; a coolant circuit connecting these components; a housing storing these components; a coolant circulating unit that circulates a coolant to the laser beam generating unit, the heat exchanger, and the coolant bypass circuit with the aid of the coolant circuit; a first valve that adjusts a flow rate of the coolant supplied to the laser beam generating unit; a second valve that adjusts a flow rate of the coolant supplied to the heat exchanger; a third valve that adjusts the flow rate of the coolant supplied to the coolant bypass circuit; a dew point measuring unit that measures a dew point inside the housing; a temperature measuring unit that measures a coolant temperature; and a control unit that controls the first, second, and third valves on the basis of the dew point and the coolant temperature.

A Raman laser conversion device for generating a single longitudinal mode, SLM, laser output is disclosed. The device comprises a Raman medium that exhibits a Stokes emission when subject to pumping by a laser pump input, the laser pump input having a pump linewidth and the Raman medium having a Raman linewidth; wherein the Raman medium is configured to define feedback interfaces of a resonator such that the Stokes emission resonates within the Raman medium; and further wherein the free spectral range, FSR, of the resonator with respect to the pump linewidth and/or the Raman linewidth or a function thereof is such that only one longitudinal mode of the Stokes emission is able to resonate within the Raman medium; whereby the laser conversion device generates a SLM laser output that is frequency shifted with respect to the laser pump input.

The present disclosure provides an apparatus and a method for measuring a concentration of pollutants in water. A passive Q-switched fiber laser outputs an evanescent wave to a to-be-tested water sample after emitting a Q-switched pulse laser signal and transmitting it via an evanescent field fiber, and based on an evanescent wave change caused by an absorption effect of the pollutants in the to-be-tested water sample to the evanescent wave and an output repetition frequency change of the passive Q-switched fiber laser due to the evanescent wave change, outputs an output repetition frequency result of the passive Q-switched fiber laser. The method is simple; and the apparatus based on the method is simple in structure and low in cost.

Direct diode-pumped Ti:sapphire laser amplifiers use fiber-coupled laser diodes as pump beam sources. The pump beam may be polarized or non-polarized. Light at wavelengths below 527 nm may be used in cryogenic configurations. Multiple diode outputs may be polarization or spectrally combined.

An optical amplifier is provided in which radiation levels experienced by an optical fiber are minimized. A sealed enclosure houses an optical fiber. An input optical signal enters on end of the fiber and an amplified output optical signal exits the other end of the optical fiber. Small particles embedded with a gas fill the interior of the enclosure. An optical pump supplies an amplification laser beam coupled to one of the ends of the optical fiber. Due to energy supplied by the amplification laser beam, the input optical signal is amplified upon exiting the optical fiber. At least a portion of the gas embedded in the small particles is released inside the enclosure when the small particles are subjected to heat to provide a gaseous interior in the enclosure that minimizes radiation levels experienced by the optical fiber due to external radiation.