LDH-FA Series

• Higher excitation power
• Cleaner time-domain measurements
• More flexible experiment design
• Reliable performance at high repetition rates
• Stable output for quantitative workflows
• Precise timing in synchronized setups

The PicoQuant LDH-FA Series is a family of amplified picosecond pulsed laser diode heads designed for applications requiring significantly higher optical power than conventional picosecond laser diode sources.

The LDH-FA Series is based on a Master Oscillator Fiber Amplifier (MOFA) concept. A seed laser generates infrared picosecond pulses using PicoQuant's gain-switching technology, after which the optical signal is directly coupled into one or two stages of fiber amplification. This increases the optical output power while preserving important characteristics of the seed laser, including its wavelength, polarization, and short pulse duration.

One of the major advantages of the LDH-FA platform is its ability to combine high pulse energy with short pulse duration. The amplified infrared output can also be converted to other wavelengths using nonlinear optical processes such as Second Harmonic Generation (SHG), Third Harmonic Generation (THG), and Fourth Harmonic Generation (FHG). This enables picosecond laser operation at wavelengths ranging from deep UV to NIR.

Depending on the selected configuration, the LDH-FA Series can provide wavelengths such as 266, 355, 515, 531/532, 560, 595, 766/775, 1030/1062/1064, and 1532–1560 nm. The exact wavelength, pulse width, and output power depend on the individual laser-head configuration.

The series is particularly useful when a conventional LDH source does not provide sufficient optical power. PicoQuant specifies average output power ranging from approximately 1 mW to more than 450 mW, depending on wavelength and amplifier configuration.

The LDH-FA Series is also flexible in beam delivery. Selected versions provide a collimated free-space beam, while others are available with polarization-maintaining fiber output and FC/APC connectors. Fiber coupling is particularly useful when integrating the laser source into microscopy, spectroscopy, or other optical instrumentation.

Product Type: Amplified Picosecond Pulsed Laser Diode Head
Product Family: LDH-FA Series
Laser Architecture: Master Oscillator Fiber Amplifier (MOFA)
Wavelength Range: 266–1560 nm
Pulse Width: Down to 70 ps FWHM
Typical Pulse Width: <100 ps for many configurations
Maximum Repetition Rate: 80 MHz
Average Output Power: Up to 450 mW*
Output Type: Collimated Free-Space / Fiber-Coupled
Fiber Output: PM Fiber with FC/APC available
Fiber Options: SM / MM / PM-SM, depending on configuration
Frequency Conversion: Optional SHG / THG / FHG
Polarization: Linear / Polarization Maintaining, depending on configuration
Spectral Width: <<1 nm
Power Stability: <3% RMS over 12 h, ΔT ambient <0.5 K
Laser Driver Compatibility: PDL 800-D / Sepia PDL 828
Laser Combining: Up to 5 laser heads via LCU
Laser Class: Class 3B

1. Time-Resolved Fluorescence

• Time-Resolved Fluorescence Spectroscopy
• Fluorescence Lifetime Measurements
• Fluorescence Decay Analysis
• Time-Resolved Photophysics
• Molecular Dynamics

The combination of short pulse duration, variable repetition rate, and higher optical power makes LDH-FA suitable for demanding time-resolved fluorescence experiments.

2. FLIM / FRET / FCS

• FLIM — Fluorescence Lifetime Imaging Microscopy
• FRET—Förster Resonance Energy Transfer
• FCS — Fluorescence Correlation Spectroscopy
• FLCS — Fluorescence Lifetime Correlation Spectroscopy
• Confocal Microscopy
• Time-Resolved Imaging

Higher excitation power can be particularly useful when working with weak fluorescent signals or demanding imaging configurations. PicoQuant explicitly lists FLIM, FRET, and FCS among the target applications.

3. STED Microscopy

• STED Microscopy
• Super-Resolution Imaging
• Fluorescence Depletion
• High-Resolution Biological Imaging

The high-power pulsed output makes selected LDH-FA configurations suitable for applications requiring intense, precisely timed optical excitation such as STED microscopy.

4. Time-Resolved Photoluminescence

• TRPL
• TRPL Imaging
• Semiconductor Characterization
• Carrier Lifetime
• Exciton Dynamics
• Perovskite Research
• 2D Materials

Short picosecond excitation pulses combined with higher optical power make LDH-FA a strong source for photoluminescence lifetime and carrier-dynamics measurements.

5. Quantum Optics

• Quantum Optics
• Single-Photon Experiments
• Photon Correlation
• Antibunching
• Quantum Light Sources
• Single-Photon Generation

PicoQuant specifically lists quantum optics and antibunching among LDH-FA applications.

6. LiDAR & Ranging

• LiDAR
• Time-of-Flight Measurement
• Laser Ranging
• Remote Sensing
• Satellite Laser Ranging (SLR)

The high repetition rate and short pulse duration are advantageous for time-of-flight and ranging applications.

7. Laser Cutting & Ablation

• Laser Ablation
• Micro-machining
• Precision Material Processing
• Laser Cutting
• Surface Processing

Higher pulse energy compared with conventional picosecond diode sources enables selected LDH-FA configurations to be used for precision material processing.

8. 3D Polymerization

• 3D Polymerization
• Two-Photon Polymerization
• Microfabrication
• 3D Microprinting
• Photonic Structures

The high peak intensity of short pulses can be useful for nonlinear polymerization and advanced microfabrication processes.

9. Biochemical Analytics

• Biochemical Analysis
• Fluorescence-Based Detection
• Time-Resolved Assays
• Molecular Diagnostics
• Fluorescence Spectroscopy

The combination of wavelength flexibility and high-power pulsed excitation supports fluorescence-based biochemical analysis.

10. Diffuse Optical Tomography

• Diffuse Optical Tomography (DOT)
• Biomedical Imaging
• Tissue Optical Measurement
• Functional Imaging

The available wavelengths and pulsed operation can be integrated into optical measurement systems for biological tissue studies.