Key Photonics » Electro-Optic Systems

SELF-CONTAINED HV SWITCHING MODULE Q-SWITCH DRIVER -MODEL 5056

admin — Thu, 22 Oct 2009 15:44:32 +0000

≤ 3 Nanosecond Output Rise time
Single Shot to 5 kHz Repetition Rates
EMI/RFI Shielded Enclosure
5 kV & 8 kV Output Voltage Models
Works on +24 VDC Power Supply
High Reliability – >10 Year Lifetime

Model 5056 Q-switch Driver Modules integrate high voltage MOSFET circuits and self-contained
miniature high voltage power supplies which require only +24 volts DC input. Trigger signals
can be TTL level voltages. The 5056 is intended for stand-alone operation with the company’s
Series 1058, 1059, 1145, 1147 and 3900 electro-optic Q-switches operating at repetition
rates between single-shot and 5 kHz repetition rates. It will also drive similar Pockels cells from
other manufacturers. All circuits are packaged in an electrically shielded enclosure which
attenuates EMI/RFI to minimize radiated and conducted switching noise. The 5056 Output
voltage is conveniently adjusted by a front panel mounted miniature potentiometer.
The 5056 features a balanced output, i.e., there are 2 independent output connections, one for
each terminal on the Q-switch. The static, unswitched HV outputs have identical HV DC
levels which produce a zero net differential voltage across the crystal. Two other modes of
operation are available without modifications.
Referring to circuit diagram on page 2; when a trigger signal is applied, Side 1 switches from the
pre-adjusted HV level to ground and then, between laser pulses, is allowed to recover to its
original value.
Side 2 always remains at the original HV level so that during the time Side 1 is at the ground level
(‘ON’ Time), pre-set retardation voltage is applied to the crystal. The Q-switched pulse is
generated during the ‘ON’ time. Given an appropriate Q-switch, the 5056 permits
operation at the ¼ or ½ wave retardation voltages or at any voltage in this range. The
8,000 Volt Model 5056-8 will produce pulsed voltages suitable for ½ wave retardation at 1064 nm.

MODEL 5056 SELF-CONTAINED HV SWITCHING MODULE Q-SWITCH DRIVER DATA SHEET (PDF)

INTEGRATED DRIVER/POCKELS CELL Q-SWITCHING SYSTEMS -MODEL 5055SC

admin — Thu, 22 Oct 2009 15:31:41 +0000

LASERMETRICS ® 5055SC Systems incorporate the latest HV MOSFET technology with the company’s
well known high speed Pockels cell Q-switches. The combination is intended primarily for laser Q-switching
and cavity dumping and can also be utilized for pulse selection, extraction, seeding and chopping. With
appropriate Pockels cells, a system can operate over a wavelength range of 250 nm to 1300 nm.
FEATURES

Self-contained HV Power Supply
Gimbal Mounted Pockels Cell
Accepts most 1 3/8″D Pockels Cells
High Reliability & Small Footprint
≤ 3 Nanosecond Optical Rise Time
Optical or Electrical Triggering
Repetition Rates up to 1000 pps
EMI/RFI shielded enclosure

5055SC Systems feature a High Voltage Pulse Module with a self-contained high voltage supply
which requires only +24 volts DC input. An AC to +24VDC miniature converter is available for
supplying the required DC voltage. High voltage is adjusted to the required level by an integral
miniature potentiometer. The HV Pulse Module can be triggered from conventional TTL pulse sources.
Repetition rates of 1000 pulses per second are attained with the standard HV Pulse Module.
Higher repetition rates, up to 5,000 pps, are available at lower voltages and with a larger
module. 5055SC Systems incorporate an EMI/RFI shielded enclosure with no exposed HV terminals
as shown on the outline drawing.

The Pockels cell operates with no static DC high voltage applied – the driving pulse switches from
zero to the preset operating HV level. This feature prevents cumulative ion migration damage which
occurs in KD*P crystals with application of continuous DC voltage. Since both Pockels cell
and HV Pulse Module are rigidly fixed to the gimbal mounting surface and no stiff HV cables are
required, there is no tendency for the alignment to change because of pressure from cables.
KD*P Pockels cells (Series 1059) are useful with large beam diameters and where peak power
densities exceed 750 MW/cm2, 20 ns pulse width.
RTP Pockels cells (Series 1147) are recommended for operation where high average power, freedom
from piezoelectric ringing or wavelengths longer than 1100 nm are needed. Both types of Pockels
cells offer highest transmittance, nominally 98.5%, in the range of 800 nm to 1100 nm.
5055SC with Pockels Cell Cover Shield Removed.
Sol Gel antireflection coatings for the KD*P crystal surfaces can reduce reflectance to 0.05% per
surface. These coatings are valuable in high fluence lasers – they do not cause non-linear absorption
effects or contribute to thermally induced beam distortions.
NOTE: The 5055SC is available without a Pockels cell to accommodate customers who have a suitable
device. It can be supplied with an adaptor to hold an industry standard, 1.375″ diameter cell or with
an aluminum plate adaptor which mates with the system mounting gimbal. The plate can be modified
to hold a variety of Pockels cell shapes.

MODEL 5055SC INTEGRATED DRIVER/POCKELS CELL Q-SWITCHING SYSTEMS DATA SHEET (PDF)

SELF-CONTAINED Q-SWITCHING SYSTEMS – MODEL 5055EH

admin — Thu, 22 Oct 2009 15:04:22 +0000

SELF-CONTAINED Q-SWITCHING SYSTEMS – MODEL 5055EH Data sheet (pdf)

Q-SWITCHING SYSTEMS – 5048 SERIES

admin — Thu, 22 Oct 2009 14:54:34 +0000

Pulse Voltages up to 8 kV
Repetition Rates up to 5 kHz
Completely Solid State
Rise times less than 10 nanoseconds
Wavelengths from 300 nm to 2500 nm
Operates safely with KD*P, CdTe, BBO LiNbO3 and other Q-switch materials
Available with EMI/RFI suppressed HV Driver / Optical Head Assembly.

Meets European CE Mark requirements

5048 System design applies the latest technology in high voltage field effect transistor circuits.
Capable of switching speeds of 5 nanoseconds and operation at up to 5 kHz, 5048 Systems provide
versatility, high reliability, and ease of use.
Systems are available with KD*P Q-switches for operation at wavelengths ranging from 300 nm to
1100 nm or with lithium niobate Q-switches for wavelengths from 700 nm to 2500 nm. Wavelength
range for a particular crystal material is a function of the anti-reflection coatings on the Q-switch.
Brewster angle cut lithium niobate crystals are available for use over the full range of crystal
transmission.
5048 Systems consist of a Power Supply / Pulse Timing Generator, a HV Pulse Output Module and
a Q-switch. A Glan-Laser Air Spaced Polarizer may also be specified. The HV Pulse Module should be
in close proximity to the Q-switch and the Power Supply / Timing Generator is remotely located .
5048 systems can operate over a wide range of output pulse voltages with no change in the output
pulse waveform. A unique characteristic of the FET HV output switches is that the output pulse rise time
remains constant over the full range of output voltages.
Pulsed output voltage of the HV Switching module can be manually adjusted by a front panel control
on the power supply to accommodate quarter wave or half wave operation. This may be accomplished
for wavelengths up to 2500 nm for lithium niobate Q-switches and up to 1100 nm for KD*P Qswitches.
KD*P Q-switches with sol gel antireflection coatings on the crystal are recommended for use with large
beam diameters (>8 mm) and where peak power densities of more than 750 MW/cm2 (#10 nsec
pulse width) are present. Lithium niobate is recommended for applications with high repetition
rates (>100 pps) and peak power densities of <250 MW/cm2.
For OEM and other applications where the HV Switching Module and Q-switch are enclosed in a
shielded enclosure, the configuration pictured above is recommended. Where the Module and Qswitch
are not so enclosed and high voltage switching noise must be suppressed, the Optical
Head Assembly enclosure shown on the following page should be specified. This enclosure complies
with all requirements of the new European EMC regulations for radiated and conducted emissions.