Koheras HARMONIK

Low Noise Single Frequency 2nd Harmonic Laser
SystemPRODUCT GUIDE

Item 800-604-01

PRODUCT GUIDEThis guide includes the following NKT Photonics products:

Koheras HARMONIK
Low Noise Single Frequency 2nd Harmonic Laser System

Koheras HARMONIK Product Description Release 2.1 02-2021 W-10456

GUIDE OVERVIEWThis product guide is intended to provide functional, operational and installation
information for the Koheras HARMONIK laser systems. The guide is divided into
three sections:•

Koheras HARMONIK Description - introduces the Koheras HARMONIK
system, its functionality, interfaces and variants.

•

Installation – includes the details on how to install the system and connect
optional interfaces.

•

Operations – – provides information and procedures on how to connect,configure and manage the system.

The Koheras HARMONIK system consists of three modules. This guide provides
details for the harmonic generator module. For details on operating the seed andamplifier lasers, refer to the following documents:
Koheras ADJUSTIK Product Guide
Koheras BOOSTIK HPA Product Guide
Warning: Do not operate the laser before first reading and understanding all
warnings, cautions and handling information stated within the document:
Koheras HARMONIK Safety, Handling and Regulatory Information
Note: The paper copy of this document is included with your laser; however, it
can also be downloaded from:https://www.nktphotonics.com/lasers-fibers/support/product-manuals/

Target audience This guide is for technical personnel involved in the selection, planning anddeployment of lasers in laboratory and industrial settings. The guide assumes areasonable knowledge level of lasers, photonic principles and electrical interface
connectivity.

Chapters inside This guide includes the following chapters:•

Chapter I “HARMONIK System Description” — Describes the laser system
including its general operational principles, management and interfaces.

•

Chapter 2 “Installation” — Contains information on installing and connecting
the Koheras HARMONIK.

•

Chapter 3 “Operations” — Provides information on turning on, connecting,configuring and operating the Koheras HARMONIK.

3

•

Appendices — The appendices contain system specifications and service andsupport information.

Added information Lasers are highly dangerous devices that can cause serious injury and property
and safety notices damage. This guide use the following symbols to either highlight important safety
information or provide further information in relation to a specific topic.

Note: Highlights additional information related to the associated topic and/or
provides links or the name of the NKT guides describing the additional information.
Caution: Alerts you to a potential hazard that could cause loss of data, or damage
the system or equipment.
Warning: The laser safety warning alerts you to potential serious injury that may
be caused when using the laser.

Revision The section records the document revision details.
February 2020 – First release. Note that this document has been rewritten froman earlier draft release.
September 2020 – Corrected some procedures orders and text through out.
December 2020 – Released revision 2.0 to reflect design change implementing
a built-in controller within the HARMONIK.
January/February 2021 – Updated support contact details in Appendix B. Minor
corrections and updated figure 10.

4

CONTENTS
Guide Overview ................................................................................................................... 3

TABLES ..................................................................................................................... 7
FIGURES ................................................................................................................... 9
PROCEDURES .........................................................................................................11
1 HARMONIK System Description ....................................................................................13
Models .....................................................................................................................13
Installation ..............................................................................................................13
Optical .......................................................................................................................... 14
Output power and wavelengths .......................................................................14
Emission beam quality ........................................................................................14
Free-space or fiber output .................................................................................14
Laser classification ...............................................................................................14
HARMONIK module .................................................................................................. 15
Front panel ............................................................................................................ 15
Rear panel ............................................................................................................. 16
Optional fiber coupling ...................................................................................... 16
Miscellaneous ............................................................................................................ 16
Safety ...................................................................................................................... 16
CONTROL and CONFIGURATION .........................................................................17
Management software ........................................................................................17
Management connection ....................................................................................17
Chassis labels............................................................................................................. 19
2 Installation ............................................................................................................................21
General ........................................................................................................................ 21
Requirements ....................................................................................................... 21
Room requirements ............................................................................................ 21
Electrical supply requirements ........................................................................ 22
Installing the system ................................................................................................ 22
5

Seed and amplifier modules ............................................................................ 23
Connecting the system ........................................................................................... 23
3 Operations ..........................................................................................................................27
Safety ........................................................................................................................... 27
Damage prevention ................................................................................................. 27
General ........................................................................................................................ 27
Stability .................................................................................................................. 27
Temperature Optimization ............................................................................... 28
Client software ..................................................................................................... 28
Management window .............................................................................................. 28
Temperature/Wavelength operating mode ................................................. 29
Power ..................................................................................................................... 29
Status panel .......................................................................................................... 29
Using the system ...................................................................................................... 30
Initial use ............................................................................................................... 30
Optimizing the SHG output - using temperature control .......................... 31
Optimizing the SHG output - using wavelength control ........................... 32
Auto temperature button .................................................................................. 34
Fiber procedures ................................................................................................ 34
A Specifications .................................................................................................................... 35
B Service and support Information ...................................................................................37
Servicing the laser .................................................................................................... 37“WARRANTY...” Label .........................................................................................37
Opening the modules ........................................................................................37
Support contact details ........................................................................................... 38
Support website .................................................................................................. 38
Shipping address ................................................................................................ 38

6

TABLES
Table 1: HARMONIK system models................................................................................. 13
Table 2: Optical interface parameters @ 20 W BOOSTIK HP output power......... 14
Table 3: Module labels......................................................................................................... 19
Table 4: Optical module installation requirements ..................................................... 23
Table 5: Mechanical dimensions ..................................................................................... 35
Table 6: Operating and storage environment ............................................................. 35
Table 7: Electrical ................................................................................................................. 35
Table 8: Safety and regulatory compliances ............................................................... 35
Table 9: Mechanical dimensions...................................................................................... 367

8

FIGURES
Figure 1: Optical module front panel ............................................................................... 15
Figure 2: Optical module rear panel ............................................................................... 16
Figure 3: Optical module rear panel ............................................................................... 16
Figure 4: USB connectivity ................................................................................................. 18
Figure 5: Label locations ...................................................................................................................20
Figure 6: Optical module rear panel .............................................................................. 22
Figure 7: Removing the optical input cover .................................................................. 24
Figure 8: Installing the collimator assembly ................................................................. 25
Figure 9: Replacing the optical input cover ................................................................. 25
Figure 10: Client – main window ..................................................................................... 28
Figure 11: Management client – Temperature control ................................................ 31
Figure 12: Management client – Temperature control .............................................. 33
Figure 13: Warranty seal .....................................................................................................37
white

9

10

PROCEDURES
Procedure 1: Connecting the system.............................................................................. 23
Procedure 2: Initial use ...................................................................................................... 30
Procedure 3: Optimize second harmonic emission level using temperature ..... 32
Procedure 4: Optimize second harmonic emission level using wavelength....... 33

11

12

1

HARMONIK System Description
The HARMONIK system is a high-power frequency doubled laser system. The system
is modular and consists of the following modules:•

HARMONIK module – the module houses the HARMONIK’s opticalcomponents for frequency doubling the source laser beam. Specifically, this isa photonic crystal operating at 50-65° C (for 775 fiber) that ensures high-power
delivery. The module also includes an electronic interface for control of themodule from a PC.

•

Koheras ADJUSTIK – laser seed source. The emission from the ADJUSTIK isdelivered to the BOOSTIK HPA.

•

Koheras BOOSTIK HPA – Amplifies the seed laser to provide up to 15 W ofpower from the optical module in a standard system. Higher custom power
levels are available on request.

Note: All modules are specifically aligned at the factory and cannot be replaced without NKTP support.
This guide describes the Koheras HARMONIK module in detail. For details of thesystem’s seed and amplifier laser modules, refer to the following NKTP guides:
Koheras ADJUSTIK Product Guide
Koheras BOOSTIK HPA Product Guide

Models The Koheras HARMONIK system models are listed in Table 1. The two systems aredefined in the table by their advantages and particular optical specifications.
Table 1 HARMONIK system models
Model

Advantage

Specification

C7

Low Relative Intensity
Noise (RIN)

RIN: -140 dBc/Hz @ 10 MHz

E7

Narrow line width and low Line width: < 0.2 kHzphase noise
Phase noise:-87 dB(rad/√Hz/m) at 10 Hz.

Installation The HARMONIK module is designed to be placed on a table or shelf installation. The
Koheras ADJUSTIK and BOOSTIK HPA modules can be either racked mounted in astandard 19 inch rack or directly placed on a flat surface such as table or shelf.

13

OpticalOpticalOutput power and Table 2 lists standard wavelength and power specifications. Contact NKT Photonics
wavelengths to discuss your requirements and options available.
Table 2 Optical interface parameters @ 20 W BOOSTIK HP output power
Parameter

C7

E7

Center wavelengths (nm)766-780 and 1533-1560

766-780 and 1533-1560

SHG output power (W)>4i or >7ii

>4i or >7ii

Fundamental power (W)>4i or >7ii

>4i or >7ii

i.
ii.

@ 1533-1560 nm@ 766-780 nm

Note: For all other HARMONIK specifications refer to the product datasheet.

Emission beam The beam quality, M2 is less than 1.1 and is suitable for advanced quantum physics
quality projects such as quantum sensing and laser cooling and trapping. Contact NKT
Photonics to discuss the applications that are possible.

Free-space or fiber By default, the HARMONIK systems are equipped with free-space output apertures. If
output a fiber coupling is required, an efficient coupling using NKTP’s unique polarizationmaintaining single mode fiber can be included.

Laser classification The optical output is classified as a CLASS 4 laser emission.

14

HARMONIK module

HARMONIK module
Front panel The HARMONIK module front panel houses the electrical interfaces and an

optical input assembly in a cut-out along the front and right side panel as shownin Figure 1.
Figure 1 Optical module front panel
Caution: DO NOT REMOVE or LOOSEN
the screws marked with the Caution
symbol in this image.

1

2

4
3

1

Management USB port

3

Collimator assembly (cover off)2

12 VDC input

4

Optical input aperture

Management port
The HARMONIK module is managed directly from a PC connected to this USB type B
port, see - “Management connection” on page 17.
12 VDC input
Connect this Kycon KPP-4P port to the included AC mains to 12 VDC power adapter.
Collimator assembly and cover
The assembly consists of a collimator and a holder with alignment pins that insert into
the Optical module chassis for correct alignment. The assembly is aligned at thefactory so that the collimator output is aligned with the input aperture of the opticalmodule.
Caution: Under no circumstances should the collimator assembly be disassembled by unscrewing the collimator clamp screws.
Optical input aperture
The emission from the BOOSTIK HPA is coupled through the collimator assembly tothe optical input aperture from the factory aligned collimator assembly.

15

Miscellaneous

Rear panel The rear panel houses two free-space output apertures.
Figure 2 Optical module rear panelzyx

Fundamental output
aperture

2nd Harmonic
output aperture

Fundamental output apertureThis free-space aperture emits the residual fundamental beam with verticalpolarization (z-axis in Figure 2).
Second harmonic output apertureThis free-space aperture emits the second harmonic beam with vertical polarization(z-axis in Figure 2).

Optional fiber Pigtail fiber coupling are available as an option and can be fitted to one or both of thecoupling laser output apertures. The polarization axis for a fiber connector output is parallel tothe fiber coupler alignment key.

Figure 3 Optical module rear panel

Miscellaneous
SafetyWarning: The Koheras HARMONIK system emission is rated as Class 4 laser andis therefore hazardous. Before turning on the laser, ensure to read and understand all safety statements of the document:
16

CONTROL and CONFIGURATION

Koheras HARMONIK Safety, Handling and Regulatory Information
A paper copy of this document is included with your laser. If you do not have accessit, you can download a copy from:https://www.nktphotonics.com/lasers-fibers/support/product-manuals/

CONTROL and CONFIGURATIONManagement The HARMONIK module is managed using client software executable from a PC
software connected over USB to the HARMONIK module. The client can be used to:•

Configure the temperature setpoint of the second harmonic conversion
crystal oven.

•

Auto-configure the temperature setpoint where the optimum efficiency of thesecond harmonic conversion is obtained.

•

Configure the SHG wavelengths corresponding to a second harmonic crystal
oven temperature.

•

Monitor the input optical power (pump) and the 2nd harmonic output power(SHG).

•

Upgrade the HARMONIK firmware.

For information regarding the client software and using it see “Operations” onpage 27.
Note: The seed and amplifier lasers are controlled using NKT Photonics CONTROL
Graphical User Interface (GUI) software client installed on a PC or the front panel interface. For managing these modules of the system, refer to their respective productguides:Koheras ADJUSTIK Product Guide
Koheras BOOSTIK HPA Product Guide
Note: DO NOT OPERATE the laser system until you are familiar with the controls andhave taken all precautions necessary for your region and as described in the document: Koheras HARMONIK Safety, Handling and Regulatory Information.

Management The HARMONIK module connects to a PC over a USB2 serial connection using a aconnection standard Type A to B USB cable.
Note: The maximum cable length is typically limited to 2 meters maximum

17Chassis labels

Chassis labels
A Koheras HARMONIK chassis has a number of labels on it that indicate hazards,
regulatory, or manufacturing information. The labels are described in Table 3 with thelabel placements shown in Figure 4.
Table 3 Module labels
Label

Panel

Description

Classification Emission
Hazards

Top

Safety information stating the laser
emission hazards and the laser’s class
rating.

Product
Information

Top

Manufacturing

Side

Manufacturing information including
address, part and serial number, datemanufactured and regulatorycompliance.

Laser Radiation Top
Warning

Safety information alert indicating thisarea of the laser is near a source of
dangerous laser emissions.

Warranty Seal

Safety information alert indicating thelocation of the aperture where laser
radiation is emitted from the laser. If themodule includes a monitor output, this isa class 1 laser output and does not
require a a label.

Side

Laser Aperture Rear

Safety label showing the emission
specifications of the laser.

Safety information alert indicating thelocation of the aperture where laser
radiation is emitted from the laser. If themodule includes a monitor output, this isa class 1 laser output and does not
require a a label.

18

DANGER - INVISIBLE LASER RADIATIONAVOID EYE OR SKIN EXPOSURE TO
DIRECT OR SCATTERED RADIATION
CLASS 4 LASER PRODUCTMAXIMUM OUTPUT POWER: 15 W
WAVELENGTH: 500 - 2100 nm
EN60825-1:2014

WARRANTY VOID IF SEAL
IS BROKEN OR REMOVEDLASERAPERTURE

Chassis labels

Figure 4 Label locations

Rear
LASER
APERTURE

LASER
APERTURE

DANGER - INVISIBLE LASER RADIATIONAVOID EYE OR SKIN EXPOSURE TO
DIRECT OR SCATTERED RADIATION
CLASS 4 LASER PRODUCTSideMAXIMUM OUTPUT POWER: 15 W
WAVELENGTH: 500 - 2100 nm
EN60825-1:2014

Top

WARRANTY VOID IF SEAL
IS BROKEN OR REMOVED

Front

19

Chassis labels

20

2Installation

GeneralInstall the system modules on a level surface that is free from vibrations. The
ambient temperature surrounding any of the optical modules should be stableand free from any sources that could cause temperature fluctuations.
Temperature changes and vibrations may affect the laser system’s operation andresult in abnormal operation.
Warning: Align the fundamental and second harmonic laser apertures with an appropriate beam dump and ensure the beam path is safely contained and known
to prevent damage and accidental exposure to personnel. All nearby personnel
must wear suitable clothing and be aware of the laser operations and the danger
involved. Ensure that a door interlock is used for any access to the contained operating area. For further safety recommendations, READ the NKTP document:
Koheras HARMONIKs Laser Safety, Handling and Regulatory Information

Requirements Ambient Conditions:•

Allowable operating system temperature range: +15° C to +30 °C•

Protection from dust (Pollution degree 2, Office environment)•

Allowable relative humidity: 0 to 70% (non-condensing)Room requirements The HARMONIK module is classified as a Class 4 laser product. As such, NKT

Photonics recommends that the system is installed and operated according to
the requirements in:•

CFR21 1040.10 & Laser Notice LN50•

IEC / EN 60825-1

Note: Installation and operational requirements defined by regional regulations
prevail.
Warning: At all times during system operation, ensure that the beam paths are
known and controlled. Wear suitable protection and make sure everybody in thelaser area is aware of the fact that the system is being operated.

Electrical supply The supply voltage for the power adapter is 100-240 VAC, @ 100 W maximum.
requirements

21

Installing the system

Installing the system
The HARMONIK module is designed to be fastened on an optical table with M6holes spaced apart by 25 mm. Alternatively, the module can be clamped to any
table using the four clamp slots available on the left and right panels. Appendix 4lists the recommended requirements for the installation.
Table 4 list all requirements for the optical module installation. NKTP
recommends to adhere to these requirements. Doing otherwise may result in
improper operation of the system.
Figure 6 Optical module rear panel
6 x M6 mounting holes

Clamp slots

Caution: Before fastening the optical module to a table top, ensure the area beneath module is clean and free from debris or any corrosive chemicals.
Note: To maintain adequate heat dissipation, it is recommended to use a metallic
installation surface for heat conduction.
2

22

Connecting the system

Table 4 Optical module installation requirements
Requirement

Specification

Instruction

Surface typeHeat and electrically conductive

NKTP recommends to install the optical module on
an electrically grounded surface.

Surfaceflatness

As flat as possible

The installation surface should be as flat as possible
to avoid twisting of the module.

Surface finish

None

NKTP recommends to install the laser on a smoothsurface free from irregularities. When installing themodule, handle it with due care.

Mounting
Screws

5 X M6 X 50 mm ISO4762 Stainless-steel

The optical module can be fastened to a supporting
surface using the module’s six mounting holes withthe specified mounting screws.

1 X M6 X 20 mm ISO4762 Stainless-steel (under thecollimator cover)
NOTE: This screw size gives a penetration depth of~ 7 mm. Select a screw length according to theinstallation surface.

To MINIMIZE TORSION ON THE MODULE, alternate
tightening the screws using a crisscross pattern
while progressively increasing the torque:
NOTE: The module can be alternatively clamped toa table using the two clamp slots on the left andright panels.

Installing the seed Refer to the NKT Photonics documents:
and amplifier
modules Koheras ADJUSTIK Product Guide
Koheras BOOSTIK HPA Product Guide
Caution: The amplifier is equipped with an output assembly consisting of a fiberand collimator. Although the fiber has a minimum bend radius of 10 cm, the bestpractice is to keep the fiber as straight as possible.

Connecting the system
Procedure 1: Connecting the system
1.

Install the HARMONIK module according to the requirements of section:“Installing the system” on page 22.

2. Connect the main optical output from the ADJUSTIK to the optical input of
the BOOSTIK HPA.
3. Connect the HARMONIK fiber and collimator assembly to the optical
output of the BOOSTIK HPA.

23

Connecting the system

4. Align the collimator assembly output with a power meter and adjust theoutput from the ADJUSTIK laser and BOOSTIK HPA amplifier asnecessary.
Note: For information on Koheras ADJUSTIK and BOOSTIK HPA operations, referto the NKT Photonics documents:
Koheras ADJUSTIK Product Guide
Koheras BOOSTIK HPA Product Guide
5. Remove the cover as illustrated in Figure 7 to allow access for installingthe collimator assembly.
Figure 7 Removing the optical input cover

6. Mount the collimator assembly to the optics head by inserting itsalignment pins into the baseplate holes, see Figure 8. The lateralpositioning of the collimator is defined by the two alignment pins.
Caution: Before tightening the screws, ensure that the collimator socket sits firmly onto the baseplate without any gap.
7. When the collimator assembly is positioned correctly, fasten it to thebaseplate of the module using the included 4 screws as shown in
Figure 8.

24Connecting the system

Figure 8 Installing the collimator assembly
Caution: DO NOT REMOVE or LOOSEN
the screws marked with the Caution
symbol in this image.

Alignment
pins

8. Replace and fasten the cover over the collimator assembly.
Figure 9 Replacing the optical input cover

9. Connect the included power supply to the “Supply” connector on the rearof the HARMONIK module and then plug it into AC mains.
10. Using a USB cable, connect the HARMONIK module to a local PC.
11. See “Operations” on page 27 for information on how to manage andoperate the HARMONIK module.

25

Connecting the system26

3Operations

SafetyBefore you connect power to the Koheras HARMONIK system, ensure that you
are completely familiar with and follow all safety information andrecommendations stated within this document and the document:
Koheras HARMONIK Safety, Handling and Regulatory Information
You must follow all safety regulations required at the location where the system
will be operated.
Warning: Enabling emission of the system lasers will emit hazardous laser Class
4 radiation. Before using the system, ensure to observe and implement all safety
regulations, warnings and cautions found in the Safety, Handling and Regulatory
Information documents available and included with each component of the system.
Warning: The Koheras HARMONIK does not have a power ON switch. Optical
output is emitted from the HARMONIK module when the fundamental laser input
is active.

Damage prevention
Warning: Ensure any fiber connector faces (tip) are clean. Optical power transmitted through a dirty connector face may burn particles and damage the connector.
See “Patch cable connector cleaning” on page 34.
Note: When connecting the output fiber patch cord, ensure to match it with an appropriate fiber type.
Caution: Do not enable emission from the laser system components if they havebeen exposed to temperature and humidity beyond the operating specifications.
The lasers are designed to operate in a non-condensing environment from +15° C
to +30° C. Before turning on the system components, allow them at least 30 minutes to stabilized at the operating room temperature. A laser system component
that is too cold or hot may lead to damage.

GeneralStability The Koheras HARMONIK should remain electrically powered ON to obtain best
stability (i.e. crystal operating temperature), even if the fundamental laser isswitched off.
27

Management window

Warning: The Optical module does not have a separate optical switch or shutter
and provides a laser output as soon as the fundamental laser input is active.

Temperature If the wavelength or power of the fundamental input is altered, using the client
Optimization software controls, it may be necessary to optimize the temperature setpoint toachieve the maximum second harmonic output – see “Optimizing the SHG output- using temperature control” on page 31.

Client software The client software is included on a USB stick included with the HARMONIK
system. To install and execute the client, do the following:1.

Insert the included USB stick in your PC.

2. Copy the folder: Control Software from the USB stick to your PC.
3. Ensure the 12 VDC power adapter is connected to the HARMONIK and
AC mains.
4. Open the Control Software folder on your PC and double click theexecutable file: Koheras Harmonik 1.3.exe
Note: You can also download the Koheras HARMONIK Control Software from theNKT Photonics website, click or copy the link below into a browser:
https://www.nktphotonics.com/lasers-fibers/support/software-drivers/

Management window
When the client starts, a management window appears as shown in Figure 10.
Figure 10 Client – main window

The window includes the following:28

Management window

Temperature/ Click the down arrow at the upper left of the window and from the drop down list
Wavelength select either Temperature or Wavelength operating mode:
operating mode
• Temperature: The crystal actual and setpoint temperatures are shown alongwith a graph of the crystal temperature.

•

Wavelength: The crystal set output wavelength and actual output wavelength
are displayed along with a graph of the actual crystal output wavelength.

Autosearch
Click the Autosearch button to automatically set the oven temperature that
achieves the optimum crystal conversion efficiency of second harmonic power.
ActualDisplays either the actual crystal temperature or output wavelength dependingon the display mode selected by the “Temperature/Wavelength operating mode”
drop down.
Setpoint
Text input or up/down arrow controls for the target crystal temperature or output
wavelength. When the temperature or wavelength target is set with this control,
the HARMONIK automatically adjusts the oven temperature to achieve thesetting.
Note: When a new setpoint is set or Autosearch is click, the system automaticallyadjusts the oven to achieve the setting. Before reaching the setting, the systemtemperature oscillates up and down around the setpoint before it settles on therequested configuration.

Power Under Power are two graphs that indicate emission power levels at the
HARMONIK module.

Pump power
This graph shows the power level in Watts of the fundamental input emission.
SHG power
This graph shows the power level in Watts of the second harmonic output
emission.

Status panel The status panel is located on the right side of the client window with a red

background. It displays indicators, readings and system information for the
HARMONIK module. It also includes a firmware upgrade button at the bottom of
the panel.
Connection
Indicates an established connection with the management client software.

•

Green - management client software is connected to the HARMONIK.

29

Using the system•

Red - management client software is disconnected from the HARMONIK.

Note: If the management software is disconnected, check either the USB cable to
the PC or the DC power adapter connection to the HARMONIK.
TemperatureThis indicator shows when the SHG crystal has reached and stabilized at a set
operating temperature.

•

Green - SHG crystal set temperature has been reached and has stabilized.

•

Red - SHG crystal set temperature has not been reached.

Module Info
This section shows the following:•

Serial number of the HARMONIK module•

Installed firmware version

Measurements
This section shows the following•

Baseplate – Measured baseplate temperature, degrees C•

Operation time – The accumulated operation time in hours. Operation meansthat input pump power is detected, h - hours.

•

Pump Watthours – The accumulated amount of pump Watt hours are
displayed, for example, 100 hours of operation at 2 W is equivalent to 200
Wh, Wh - Watt hours.

•

SHG Watthours – The accumulated amount of SHG Watt hours are
displayed, for example, 100 hours of operation at 2 W is equivalent to 200
Wh, Wh - Watt hours.

Upgrade button
To upgrade the HARMONIK firmware, click the Firmware Upgrade button andthen click on the browse button to select a new firmware file. Click Open andwait for the upgrade to complete and the system to reboot.

Using the system
Initial use Follow Procedure 2 when starting up the Koheras HARMONIK system for the first
time:

30

Using the system

Procedure 2: Initial use
1.

Set the fundamental input power from the BOOSTIK HPA amplifier to a
low value i.e. P < 1 W – see document:
Koheras BOOSTIK HPA Product Guide

2. Check if the beam profile as well as beam position of the generated
second harmonic output are as expected.
3. ONLY increase the fundamental input power from the BOOSTIK HPA, if
the beam profile and position are both satisfactory and safe.

Optimizing the SHG The optical components of the Koheras HARMONIK includes an oven-controlled
output - using crystal which generates the second harmonic emission. After the system istemperature control warmed up, the temperature setpoint of the oven can be adjusted to optimize the
HARMONIK conversion output.

The configuration is performed using the client temperature setpoint as shown in
Figure 11. Typical temperature settings range from either:•

90 to 105 °C for 767 nm•

50-65° C for 775 nm•

125-135° C for 780 nm

Figure 11 Management client – Temperature control

Autosearch button – automatically adjusts the oven temperature to the optimum.
Actual – Crystal oven measured temperature
Setpoint – Crystal oven set point temperature - adjustable (numeric input or arrow keys)
Pump Input – Fundamental input emission measured power level
SHG Output – Second harmonic emission output level31

Using the system

Warning: Depending on temperature setpoint optimization, nearly the entire fundamental input power is transferred to the fundamental laser output.
Procedure 3: Optimize second harmonic emission level using temperature
1.

Turn ON the system, enable emission and wait for the HARMONIK crystal
to warm-up until the temperature in the Actual field stabilizes –approximately 5 minutes.

2. Ensure the power level in the Pump Input field is at the desired value. If
not, make the necessary changes on either the seed or amplifier lasers of
the system or the connecting emission path.
3. Note the SHG Output value.
4. Adjust the Setpoint field either up or down and wait for the Actual field toreach the new temperature setting.
Note: To adjust the Setpoint temperature, you can either input the temperature directly in the text field or use the up and down arrow keys ( ) to the left of the text
field.
5. Observe the SHG Output value.
a. If the SHG Output decreases- adjust the Setpoint field in the opposite
direction.
b. If the SHG Output increases – adjust the Setpoint field in the same
direction.
6. To reach the optimum setting, continue adjusting the Setpoint field
incrementally increasing power up to the point just before the power
decreases again.
Note: Typically increase and decrease the Setpoint temperature in set sizes of either 0.01 - 0.1 ° C; particularly when you are near the optimum conversion setting.

Optimizing the SHG Instead of optimizing using a temperature setpoint, you can set a wavelength
output - using setpoint. After the system is warmed up, a wavelength setpoint can be set which
wavelength control corresponds to a calibrated oven temperature when adjusting for the optimum
HARMONIK conversion output.

Figure 12 shows the management window when optimizing the wavelength
setpoint. Upon initial startup, set the wavelength to match the fundamental input
wavelength. To optimize the output click the manual step buttons ( ) or Autosearch button. Stepping up or down the wavelength slightly corresponds to achange in the crystal oven temperature. Typically step sizes are approximately:•

0.01°C ~ 0.0015nm step•

0.1°C ~ 0.015nm step

32

Using the system

Figure 12 Management client – Wavelength control

Autosearch button – automatically adjusts the oven temperature to the optimum.
Actual – actual measured wavelength
Setpoint – configured wavelength
Pump Input – Fundamental input emission measured power level
SHG Output – Second harmonic emission output level

Warning: Depending on wavelength setpoint optimization, nearly the entire fundamental input power is transferred to the fundamental laser output.
Procedure 4: Optimize second harmonic emission level using wavelength1.

Turn ON the system, enable emission and wait for the HARMONIK crystal
to warm-up until the wavelength in the Actual field stabilizes –approximately 5 minutes.

2. Ensure the wavelength setpoint corresponds to the fundamental input
wavelength.
3. Ensure the power level in the Pump Input field is at the desired value. If
not, make the necessary changes on either the seed or amplifier lasers of
the system or the connecting emission path.
4. Note the SHG Output value.
5. Adjust the Setpoint field either up or down and wait for the Actual field toreach the new wavelength setting.
Note: To adjust the Setpoint wavelength, you can either input the wavelength directly in the text field or use the up and down arrow keys ( ) to the left of the text
field.
6. Observe the SHG Output value.
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Using the systema. If the SHG Output decreases- adjust the Setpoint field in the opposite
direction.
b. If the SHG Output increases – adjust the Setpoint field in the same
direction.
7. To reach the optimum setting, continue adjusting the Setpoint field
incrementally increasing power up to the point just before the power
decreases again.
Note: Typically increase and decrease the Setpoint wavelength in set sizes from0.002 to 0.02 nm; particularly when you are near the optimum conversion setting.
degrees Celsius to wavelength equivalents are approximately 0.01°C ~ 0.0015nm
or 0.1°C ~ 0.015nm.

Auto temperature Clicking this button, automatically optimizes the oven temperature to obtain the
button best frequency conversion output. The function automatically adjusts thetemperature in +/- 5° C increments until the optimum second harmonic power isachieved.

Fiber procedures Fiber coupling option

If one or both of the laser outputs are fiber coupled, make sure that the coupling
efficiency is optimum before increasing the fundamental input power. Use a“beam walking” procedure to obtain the maximum coupling efficiency with thefiber couplers that can be ordered with the HARMONIK.
Note: For high-power fiber coupling solutions, contact NKTP Photonics for further
information.
Patch cable connector cleaning
Due to the high power transmitted through the single mode fiber surface of the
optical connector(s), it is important to keep all connector faces extremely clean.
This is particularly important for amplified systems, where the power level is high.

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A

Specifications

Table 5 Mechanical dimensions
All chassis models
Size (H x W x D)

48.5 x 483 x 386 mm(1.91 x 19.02 x 15.20 in)

Weight< 7 kg (< 15.4 lb)

Table 6 Operating and storage environment
All Chassis Models
Operating Temperature

15° C to +30° C (59° F to 86° F)

Storage Temperature-20° C to +50° C (-4° F to 122° F)

Operating Humidity (non-condensing)

0 to 70%

Table 7 Electrical
All Chassis Models
Supply Voltage

100 – 240 VAC@ 50-60 Hz

Table 8 Safety and regulatory compliances
SafetyRegulatory

EN 60825-1:2014: Safety of laser products
Part 1: Equipment classification and requirements[Laser Class 4]
EN 61010-1:2010:Safety requirements for electricalequipment for measurement, control, and laboratory use
Part 1: General requirements

EN 61326-1:2013: Electrical equipment for measurement,
control and laboratory use
EMC requirements – Part 1: General requirements
2004/108/EC Electromagnetic Compatibility
2011/65/EC Restriction of the use of certain Hazardous
Substances in electrical and electronic equipment (RoHS)

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Table 9 Mechanical dimensions

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B

Service and support Information

Servicing the laser
The laser have no user serviceable components. In case of malfunction, contact
NKT Photonics using the support channels in section “Support contact details”.

“WARRANTY...” Caution: The unit is sealed with a label “WARRANTY VOID IF SEAL IS BROKEN
Label OR REMOVED”. It is strictly prohibited to remove the chassis cover. Opening theHarmonic module chassis or any component of the system will void the warranty.
Therefore should any component of the system malfunction, contact NKT Photonics A/S.
Figure 13 Warranty seal
WARRANTY VOID IF SEAL
IS BROKEN OR REMOVED

Caution: The HARMONIK chassis’ contain electro-static discharge (ESD) sensitive
components. To avoid permanent ESD damage, use ESD protection when handling the laser. Always connect component earth points to a ground earth withinyour facility.

Opening the There are no user serviceable components inside the modules. Should your laser
modules malfunction, and it cannot be serviced on site, it must be shipped to the NKT
Photonics office in Birkerød, Denmark.

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Support contact details

Support contact details
If you need help or have questions regarding your Koheras HARMONIK laser or
its accessories, contact NKT Photonics through our support website below:

Support website 1. Go to:https://www.nktphotonics.com/lasers-fibers/support/technical-support-andcustomer-service/
2. Scroll down and click or press:

3. Select the type of help required, fill in the form, and click or press Submit.

Shipping address NKT Photonics A/S
Blokken 84
DK-3460 Birkerød
Denmark

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Koheras HARMONIK Product Description Release 2.1 02-2021 W-10456