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Picosecond Pulsed Sources

LDH-I Series NEW

Smart Laser Diode Heads for Taiko PDL M1

  • Wavelengths between 375 nm and 1060 nm
  • Pulse widths as short as 40 ps (FWHM)
  • Repetition rate from single shot to 100 MHz
  • Pulsed, Bursts and CW operation
  • Power calibrated, operating hours counter
  • Collimated output beam, optional fiber coupling

LDH-I Series features smart laser heads compatible with the Taiko PDL M1 driver. Laser heads from this series provide wavelengths in the spectral range from 375 to 1060 nm and include a power calibration. When coupled with a Taiko PDL M1, their optical output power can be controlled in both pulsed and continuous modes. Additionally, a wavelength calibration is available in CW mode. Each laser head is identified by the Taiko PDL M1 driver and includes not only linearized calibration data but also an operating hours counter.

Pulse widths below 40 ps

All laser heads emit picosecond pulses with a full width at half maximum (FWHM) typically around 90 ps or below. For some laser heads even pulse widths below 40 ps are possible. The pulse width itself cannot be controlled directly, but does depend on the selected power level of the diode. At maximum intensity, the pulse width can broaden.

Adjustable and calibrated average power

Linear intensity ldhiThe calibrated laser heads are designed to emit a constant pulse energy at any repetition rate for a given intensity setting. Doubling the repetition rate therefore effectively doubles the average output power. Besides, the pulse energy increases linearly with the intensity setting (in %). The resulting levels of optical output power are measured and saved in the internal memory of the laser head as mW / W calibration data for all repetition rates between 1 MHz and 100 MHz typically. The average power in CW mode is calibrated as well.
Three lasing regimes of the laser diode, which depend on the intensity setting, are identified and plotted: spontaneous emission (below laser threshold), short pulse (lower intensity setting), broaden pulse (higher intensity setting). The currently set regime is recognized and shown on the local display of the Taiko PDL M1 with an intuitive color code on the intensity scale.
The achievable pulse energies are typically in the order of several tens of picojoule, which corresponds to maximum average output powers of several milliwatts at high repetition rate.

Repetition rates up to 100 MHz

All laser heads are designed to work at repetition rates from single shot up to values in the MHz range. The maximum repetition rate depends on each single diode and is typically 100 MHz. For some laser heads a maximum repetition rate of e.g., 60 MHz is recommended in order to ensure a constant pulse energy at all repetition rate.

Pulsed, bursts and CW operation

All laser heads of the LDH-I Series can be operated in pulsed, burst, and CW mode. While the pulsed mode corresponds to a constant repetition rate commonly used for time-resolved measurement, the burst mode enables generation of flexible bursts of pulses (with selectable amount of pulses and burst period) which is useful for measuring long lifetime decays, laser ranging applications and specific seeding tasks. The CW mode enables a much higher average laser power.

Hot plug capable

As an additional feature, laser heads of the LDH-I Series are capable of hot plugging. This means that swapping laser heads to change wavelength no longer requires to turn off the driver.

Fiber coupling

The laser heads of the LDH-I Series can be optionally coupled into a variety of optical fibers (multi-mode, single mode, or polarization maintaining single mode) via different connector types. We recommend FC/APC connectors for most applications, since they prevent back reflections that can interfere with laser stability. For details see our solutions for fiber coupling.

General specifications

Beam parameters
Optics focus length f' = 4.5 mm (Typ. for LDH-P/D-C-xxx)
Numerical aperture 0.55
Typical divergence (with optics) Theta parallel 0.11 mrad
Theta perpendicular 0.32 mrad
Polarization typ. linear, perpendicular to the longer axis of the elliptical beam*
PER typ. > 1:10  (> 10 dB)
Side mode suppression ratio (SMSR) typ. < 0.01
Peltier cooling stability better than 1 K for ambient temperature between 15°C and 30°C
Without fiber coupling 76 × 175 mm (diameter × length)
With fiber coupling 62 × 207 mm (diameter × length)
Spectral width**
Wavelengths < 900 nm approx. 2 to 8 nm
Wavelengths > 900 nm approx. 10 to 20 nm
CW operation < 1 nm
Power stability
12 hours, Delta T (ambient) < 3 K 1 % RMS, 3 % peak to peak

* a few exceptions may occur
** narrow bandwidth on request

Laser Class Sign

All Information given here is reliable to our best knowledge. However, no responsibility is assumed for possible inaccuracies or omissions. Specifications and external appearances are subject to change without notice.

The following tables list the pulse parameters and power values of the available wavelengths of the LDH-I Series (available between 375 and 1060 nm). The two power adjustment levels specified here refer to the same laser head. These levels can be adjusted using the corresponding driver Taiko PDL M1. The 'Low' adjustment is the best choice for shortest pulses and is usually reached close to the lasing threshold. The 'High' adjustment is used to achieve highest pulse power and corresponds to the maximum intensity setting of the driver. These laser heads have a spectral width of a few nm. Special selected laser heads with narrow spectral bandwidth can also be provided.

The table below is updated on a regular basis based on data of recently manufactured laser heads. Other specifications such as shorter pulse widths, higher powers, further wavelengths might be possible on request.
Please contact us for more information.

(± 10) [nm]
(FWHM) [ps]
Max. rep rate [MHz] High avg. power** [mW] Low avg. power*** [mW] CW power [mW]
375 IB-375-B < 40 70 4.0 1.0 10
405 IB-405-B < 50 100 6.0 0.9 50
440 IB-440-B < 80 100 6.0 1.0 50
470 IB-470-B < 70 100 7.0 0.9 50
485 IB-485-P < 80 60 3.0 1.5 40
485 IB-485-B < 90 100 7.0 1.0 50
510 IB-510-P < 100 100 1.0 0.5 15
510 IB-510-B < 110 50 5.0 0.7 40
520 IB-520-B < 130 100 5.0 0.6 20
640 IB-640-P < 55 100 1.0 0.5 5
640 IB-640-B < 90 100 25.0 3.0 50
650 IB-650-P < 60 100 1.0 0.5 5
650 IB-650-B < 70 100 8.0 2.5 10
660 IB-660-B < 100 100 10.0 3.0 50
670 IB-670-P < 50 100 2.0 1.0 2
690 IB-690-B < 80 100 7.0 1.0 20
730 IB-730-B < 80 100 9.0 3.0 20
780 IB-780-B < 70 100 20.0 1.0 40
975 IB-980-B < 90 100 3.0 0.3 40
1060 IB-1060-B < 100 100 12.0 0.6 40

* Shortest pulse width at min intensity setting above laser threshold. Possible pulse broadening at high intensity settings
 Pulses are deconvoluted with 30 ps detection IRF. Shorter pulse widths are available on demand.
** Average optical power at max repetition rate and max intensity setting
*** Average optical power at max repetition rate and min intensity setting above laser threshold

Naming scheme of the LDH-I Series laser heads

naming scheme LDH-I-Series


"I" = Taiko compatible, "intelligent"

"B" = High power

"P"= Narrow pulse


Laser sign

All measurements shown may be subject to a 10% callibration error.

Each laser head undergoes an extensive burn-in test to ensure long-term stability and is shipped with a comprehensive set of test data. This test data is kept in our database, which already holds records of more than 15 years.

All Information given here is reliable to our best knowledge. However, no responsibility is assumed for possible inaccuracies or omissions. Specifications and external appearances are subject to change without notice.

The following documents are available for download:

Latest 10 publications referencing Pulsed Diode Lasers (PDL Series, LDH-Series, LDH-FA Series)

The following list is an extract of 10 recent publications from our bibliography that either bear reference or are releated to this product in some way. Do you miss your publication? If yes, we will be happy to include it in our bibliography. Please send an e-mail to info@picoquant.com containing the appropriate citation. Thank you very much in advance for your kind co-operation.