GW Nanosecond pulsed solid-state laser repair

GW YLPN-1.8-2 500-200-F is a high-precision nanosecond short-pulse laser (DPSS, diode-pumped solid-state laser) produced by GWU-Lasertechnik (now part of Laser Components Group) in Germany. It is widely used in:

Industrial micromachining (PCB drilling, glass cutting)

Scientific research experiments (spectral analysis, laser-induced breakdown spectroscopy LIBS)

Medical beauty (pigmentation removal, minimally invasive surgery).

Core parameters:

Wavelength: 532nm (green light) or 355nm (ultraviolet)

Pulse width: 1.8~2ns

Repetition frequency: 500Hz~200kHz adjustable

Peak power: high energy density, suitable for precision machining.

2. Daily maintenance methods

(1) Optical system maintenance

Daily weekly inspection:

Use dust-free compressed air to clean the laser output window and reflector.

Check the alignment of the optical path (to avoid deviation caused by mechanical vibration).

Quarterly in-depth maintenance:

Use special optical cleaner + dust-free cotton swab to wipe the lens (do not use alcohol to avoid coating damage).

Detect the transmittance of the laser crystal (such as Nd:YVO₄) and replace it if necessary.

(2) Cooling system management

Coolant maintenance:

Use deionized water + anti-corrosion agent, replace every 6 months.

Check the sealing of the water pipe joint to prevent leakage.

Radiator cleaning:

Clean the dust on the air-cooled heat sink every 3 months (to ensure heat dissipation efficiency).

(3) Electrical and mechanical inspection

Power supply stability:

Monitor the input voltage fluctuation (need <±5%), it is recommended to equip with UPS voltage stabilizer.

Check whether the pump diode (LD) drive current is normal.

Environmental control:

Operating temperature 15~25°C, humidity <60%, avoid condensation.

3. Common faults and diagnosis

(1) Laser output power decreases

Possible causes:

Optical lens contamination or coating damage

Laser crystal (Nd:YVO₄/YAG) aging or thermal lens effect

Pump diode (LD) efficiency decreases.

Diagnostic steps:

Use a power meter to detect output energy.

Check the optical path in sections (isolate the resonant cavity and test the performance of a single module).

(2) Pulse instability or missing

Possible causes:

Q switch (such as acousto-optic modulator AOM) drive failure

Control circuit board (such as FPGA timing board) signal abnormality

Power module power supply is insufficient.

Diagnostic steps:

Use an oscilloscope to detect the Q switch drive signal.

Check whether the repetition frequency setting exceeds the limit.

(3) Cooling system alarm

Possible causes:

Insufficient coolant flow (water pump failure or pipe blockage)

TEC (thermoelectric cooler) failure

Temperature sensor drift.

Diagnostic steps:

Check the water tank level and filter.

Measure whether the voltage across the TEC is normal.

(4) The device cannot start

Possible reasons:

Main power supply is damaged (fuse is blown)

Safety interlock is triggered (such as the chassis is not closed)

Control software communication error.

Diagnostic steps:

Check the power input and fuse.

Restart the software and reinstall the driver.

4. Repair ideas and processes

(1) Modular troubleshooting

Optical part:

Clean or replace the contaminated lens → Recalibrate the optical path.

Electronic control part:

Replace the damaged Q switch driver board → Calibrate the pulse timing.

Cooling part:

Unblock the blocked pipeline → Replace the faulty water pump/TEC.

(2) Calibration and testing

Pulse detection: Use a high-speed photodetector + oscilloscope to verify the pulse width and stability.

Beam quality analysis: Use an M² meter to ensure that the beam divergence angle meets the standard.

(3) Spare parts selection recommendations

Original spare parts (such as LD modules and Q switches provided by GWU/Laser Components) are preferred.

Alternative: highly compatible third-party spare parts (parameter matching needs to be verified).

5. Preventive maintenance plan

Monthly: record output power and pulse parameter trends.

Every six months: optical cavity calibration by professional engineers.

Yearly: comprehensive inspection of cooling system and power module aging.

Conclusion

Through standardized daily maintenance + modular maintenance ideas, the life of YLPN lasers can be greatly extended and downtime can be reduced. If you need in-depth support, please feel free to contact our technical team