Ultrafast laser repair and diagnostics

The chain, and why it is the whole diagnosis

Ultrafast systems from different manufacturers share an architecture even when they share nothing else. Treating the system as a chain and finding the link where pulse energy stops being produced or stops being transmitted is the core of the diagnostic method. Everything else follows from it.

1. Pump source. A CW or pulsed pump, diode-pumped or lamp-pumped, with its own driver, thermal loop and protection. In many systems a separate boxed product with its own failure modes.
2. Oscillator. The mode-locked source that defines the pulse. Ti:Sapphire, fiber, or a seeded diode architecture, with a starting mechanism that can fail independently of the gain medium.
3. Stretcher. In chirped-pulse systems, the dispersive stage that makes amplification survivable.
4. Amplifier. Regenerative, multipass or fiber, with pump delivery, Pockels cell and driver timing, and cavity optics.
5. Compressor. Gratings, prisms or fiber, where alignment and grating condition determine whether you get pulses or a long chirped mess with the right average power.
6. Conversion stage. Where present, an SHG, THG, OPO or OPA stage that cannot exceed what the fundamental delivers to it.
7. Feedback and control. Monitor photodiodes, converter stages, interlocks, trigger and synchronization, and the software path.

A system delivering correct average power with a wrong pulse duration is a compressor or stretcher problem. A system delivering correct timing with no energy is an oscillator, pump or amplifier problem. A system with healthy fundamental and weak converted output is a conversion problem. These are different jobs, and telling them apart before opening anything is what a competent evaluation buys you.

Failure symptoms we are asked to evaluate

Ultrashort pulse laser service and ultrafast laser service across the United States and Canada, on the platforms and manufacturers listed further down this page.

Why the obvious part is often the wrong order

Four patterns on this equipment produce a symptom that points at the wrong subsystem. They are worth knowing before you order a part, because each one has sent an owner after the wrong component. All four are inside the evaluation scope, and the findings name which subsystem the fault sits in.

1. The displayed value is not a measurement

Many systems display the commanded setpoint rather than a sensed value. If the command reaches the display layer but not the current driver, the panel reads perfectly while nothing changes physically. That distinction matters to you because it decides whether the fault is in the control and readback path or in the optical chain, and those are different repairs with different parts. Establishing which one it is, on the equipment rather than from the panel, is part of the evaluation.

2. Timing is not lasing

Trigger and synchronization electronics run independently of the optical chain. A clean repetition-rate reading and a healthy sync output confirm the timing board. Whether the system is actually producing optical pulses is a separate question from whether the timing board is alive, and it is one the evaluation answers on the equipment. It matters to you because a healthy timing board is often what makes the fault look electrical when it is not.

3. Average power is not pulse energy, and pulse energy is not pulse duration

A thermal power meter integrates. It will happily report the correct number for a system whose compressor has drifted and whose pulses are ten times longer than they should be. If the experiment depends on peak intensity, average power tells you almost nothing on its own.

4. The last stage is blamed for the first stage

When a system with a conversion stage produces low visible output, the crystal is the intuitive suspect and usually the wrong one. Second-harmonic generation cannot produce more than the fundamental delivered into it. This is set out in full on the SHG and harmonic generation page.

How an evaluation runs

1. What you send. Manufacturer, model and serial number, label photographs of each module, the symptoms, your normal operating parameters and any measurements you already have.
2. Written evaluation scope. A fixed fee, what the evaluation covers, the expected turnaround and what a negative result would mean, before you ship anything.
3. What the evaluation covers. The as-received condition of the instrument, its actual configuration as labelled rather than as recorded, its supplies, cooling, interlocks and control communication, and its optical, electrical and timing behaviour, with the instrumentation named in the proposal.
4. Written findings. What was measured, what was found, which subsystem the fault sits in, what remains unknown, and the repair options with their cost and risks.
5. Your approval. Nothing is repaired, substituted or modified until you approve the scope and the price in writing.
6. Repair, validation and return. Work inside the approved scope, then electrical, optical, timing and functional validation, a written service report and documented packing.

Measurements defined per project

Every engagement names its measurements before it starts. PhaseX defines and provides the measurement capability the project requires. Depending on the system and the question being answered, that is owned, rented or qualified third-party measurement resources arranged as required. The evaluation proposal states which measurements will be made, by what method, and where each one comes from, together with the acceptance criteria the work is judged against.

In-house instrumentation currently includes a RIGOL MHO984 oscilloscope and a Joulescope JS320 for electrical, current, timing and pulse-train work. Optical metrology is specified per project and provided through owned, rented or qualified third-party measurement resources arranged as required and named in the proposal. We do not publish an equipment inventory in place of a measurement plan, and we do not offer manufacturer-equivalent calibration or certification to original published specifications where the original acceptance data and the corresponding standards are unavailable.

Platforms and manufacturers

We provide independent service and repair support across the platforms below. Configuration, parts access and required metrology decide the scope of a given job, and we confirm both with you before anything ships.

Manufacturer pages

Additional platforms supported

Required shipment components

A system that cannot be brought to its normal operating state on the bench cannot be diagnosed. For bench evaluation we normally need:

• Laser head
• Controller
• Power supply
• All interconnecting cables, including any with a non-standard pinout
• Any dedicated module required for normal operation, including conversion, trigger, pump or paired units
• Control software, license files and interface documentation, including a MATLAB or LabVIEW control path where that is how the system is driven
• Manuals, configuration sheets, acceptance data and prior service reports, however incomplete

On discontinued platforms the customer's own paperwork is frequently the only surviving record of the configuration. Send it even when it looks irrelevant.

International shipments

We receive systems from outside the United States, including from Canadian universities and research institutes. We provide the commercial documentation a repair shipment normally requires and coordinate with your shipping office. Customs classification, duties, temporary import treatment and clearance timing remain the sender's responsibility, and we do not give customs guarantees. Insurance is the sender's decision and should reflect replacement value. We document the as-received condition on arrival, which is the evidence you would need if transit damage has occurred.

Questions we are asked about these systems

Do you repair ultrafast lasers the manufacturer no longer supports?

Discontinued and end-of-support systems are the main reason laboratories contact us. In ultrafast systems the fault is frequently in a driver, a supply, thermal control, a feedback path, a fiber interface, a connector or the control electronics, and that is work we do at component level. What ends a repair is a failed custom assembly with no available substitute, not a catalog status.

Can you work on the oscillator and the amplifier, or only the pump?

All of them, and establishing which one is actually at fault is what the evaluation is for. A pump problem and an oscillator problem can present almost identically from the front panel, so the pump, the oscillator, the amplifier chain, any conversion stage and the control and feedback path are all inside the scope. The written findings name the subsystem the fault sits in rather than leaving you to infer it.

Will you quote an ultrafast laser repair before seeing it?

No. A fixed repair price before the fault is located would be a guess. We quote a defined diagnostic evaluation with a fixed fee, report the findings in writing, and only then quote the repair scope for your approval.

Scope and safety

Two limits

We are direct about the work we take on, so we are equally direct about the two boundaries.

• We do not promise a specific repair before diagnosis. The diagnostic evaluation comes first and the repair scope follows from it. A finding that a system is not economically repairable is a legitimate result, and it is delivered in writing.
• We do not certify a system to original published specifications where the original acceptance data and the corresponding standards are unavailable. We document the measured condition on arrival, the fault found, the work performed, and the measured condition on completion.

Warranty

If your system is still inside its manufacturer warranty, use the manufacturer, or get written authorization from the seller first. Our work is out-of-warranty and legacy equipment, which is where the support gap sits in any case.

Laser safety

Class 4 work is planned and executed under a project-specific laser safety plan. The required engineering controls, personal protective equipment, beam management and facility conditions are defined in writing before any energized optical work begins, and the infrastructure that plan calls for is provided within the project scope. Where a laboratory's own controls are involved, final hazard analysis and approval stay with the institution's LSO or EHS function.

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