Applied Photonics LIBSCAN 25+ User manual

Portable, Modular
Laser-Induced Breakdown Spectroscopy
(LIBS) Instrument
User’s Manual
January 2018
Applied Photonics Ltd
Unit 8 Carleton Business Park, Skipton, North Yorkshire BD23 2DE, United Kingdom
Tel [phone] Fax [phone] Web: www.appliedphotonics.co.uk

© 1998 - 2018 Applied Photonics Ltd Page 2 of 23
Contents Page
1. Introduction 3
2. Safety 3
2.1 Laser radiation 3
2.2 Note on the laser safety window material used in the modular sample chambers 6
2.3 Electrical 7
3. General description 8
3.1 Overview 8
3.2 LIBSCAN 25+ instrument console 9
3.3 LIBSCAN 25+ head 10
3.4 The integrated pulsed laser 11
3.5 Laser beam expander and plasma light collection optics 12
3.6 Imaging camera and associated components 13
3.7 Attachment of the LIBSCAN 25+ head to an optical table 13
3.8 Modular sample chambers 14
4. General operating procedure 16
5. Shut-down procedure 21
6. Maintenance and inspection 21
7. Shipping and storage 21
8. Trouble-shooting / fault finding 22
Appendices
A1 EC Declaration of Conformity 23

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1 Introduction
LIBSCAN 25+ is a fully portable Laser-Induced Breakdown Spectroscopy (LIBS) instrument adopting
the same modular design principles used in our LIBSCAN range of products. Suitable for laboratory or
field applications, LIBSCAN 25+ operates from its internal 12 Volt 8Ah Li-Ion battery and can operate
for up to 4 hrs from a single charge. Recharging is achieved using a mains plug-in adaptor Li-Ion charger
which is supplied with the instrument. The six-channel design of LIBSCAN 25+ allows for up to six
compact spectrometers to be installed (approx. 185 –900 nm), depending upon the requirements of the
intended application and budget limitations. LIBSCAN 25+ can be supplied with an optional integrated
imaging camera for recording close-up video / still images of the sample. LIBSCAN 25+ is, by design, a
Class 4 laser product although when used with one of our range of modular sample chambers the product
meets Class 1 laser safety standards.
This User’s Manual provides the necessary information needed to configure the LIBSCAN 25+
instrument and how to use it safely. It is assumed that the user will be familiar with the safety issues
arising from the use of high-power lasers and will have preferably been trained in the safe use of high-
power laser products.
2 Safety
2.1 Laser radiation
LIBSCAN 25+ contains a high-power Q-switched Nd:YAG laser (Class 4, nominally 50 mJ @ 1064 nm,
5 ns pulse length, 1 Hz pulse repetition rate) and so it is imperative that it is operated only by suitably
trained and experienced persons who are fully aware of the hazards inherent to this type of high-power
laser equipment. It is imperative also that, prior to using the equipment, an appropriate risk assessment is
conducted in such a way as to take account of the proposed use of the equipment, the environment in
which the equipment is to be operated, and how its use may affect people who are not directly involved
with the use of the equipment.
Laser product classification label
LIBSCAN 25+ is designed to meet the laser safety requirements of the relevant European standards (BS
EN 60825-1: 2014) and USA standards (ANSI Z136.1 –2014). Although LIBSCAN 25+ may be
supplied with a sample chamber which provides adequate containment of the laser radiation to Class 1
Accessible Emission Limits, it is possible for the user to operate LIBSCAN 25+ without the sample
chamber (ie. operation in “open beam” mode as may be required for certain types of experiment).
Accordingly, it is necessary to consider LIBSCAN 25+ to be a Class 4 Laser Product and so, by
definition, the equipment poses a risk of personal injury (eye, skin injury) and poses a fire risk. As with
all Class 4 laser products, appropriate safety precautions must be taken as identified via a suitable risk

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assessment conducted by the user in consultation with a suitably qualified and experienced Laser Safety
Officer.
The most significant hazard relating to exposure of personnel to the laser radiation is eye injury since
direct or scattered laser radiation produced by LIBSCAN 25+ can cause serious and permanent injury to
the eyes including blindness - such injury may be instantaneous. Precautions must be taken to avoid
exposure of personnel to hazardous levels of laser radiation. Such precautions may include the setting up
of a temporary or permanent laser controlled area (eg. a laser laboratory). Other measures may also be
necessary, as determined by appropriate and thorough assessment of the risks (ie. a risk assessment)
conducted by the personnel responsible for the safe use of the LIBSCAN 25+ instrument.
With the use of an optional adaptor, LIBSCAN 25+ may be used with any one of our range of modular
sample chambers (SC-1, SC-2, etc). The door of the sample chamber is equipped with a dual electrical
interlock switch which is designed to prevent activation of the laser unless the door is fully closed. The
interlock circuit is designed to “fail safe” so if it is not connected properly (e.g. the LIBSCAN 25+ is not
correctly attached to the modular sample chamber using the supplied adaptor), the interlock circuit is
designed to prevent activation of the laser. Removal of the sample chamber from the LIBSCAN 25+
head will also activate the interlock (i.e. prevent activation of the laser). The key-switch operated
Interlock Override (see section 3.2 of this User’s Manual) allows the safety interlock feature to be
disabled. It is necessary to use this override feature when operating the LIBSCAN 25+ without a sample
chamber (i.e. operating in “open beam” mode). In view of this, the LIBSCAN 25+ system must be
categorised as a Class 4 laser product since, by design, the product may be used in such a way that the
laser beam is not contained (i.e. “open beam” mode of operation).If, however, the sample chamber is
correctly fitted to the LIBSCAN 25+ head and the Interlock Override is switched off and the key
removed, then the laser radiation is adequately contained to Class 1 Accessible Emission Limits by the
design of the hardware. You should consult your Laser Safety Officer to ensure that this meets any local
rules and regulations concerning the operation and use of Class 4 laser systems within your organisation.
Class 4 laser interlock warning label

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IMPORTANT
READ and UNDERSTAND this User’s Manual before operating the LIBS equipment.
ENSURE that an appropriate risk assessment has been conducted to establish whether or not the laser safety windows
fitted to the modular sample chambers provide adequate protection against exposure to laser radiation for the specific
laser you intend to use with the LIBS equipment. For advice on this matter, consult your Laser Safety Officer
and/or Applied Photonics Ltd.
ONLY suitably qualified and authorised persons should activate the Interlock Override keyswitch. The key should be
removed from the keyswitch and held by the Laser Safety Officer when this feature is not required.
ALWAYS use appropriate laser safety protective eyewear when operating the LIBS equipment in “open-beam”
configuration –you should seek advice from your Laser Safety Officer on this matter.
ALWAYS switch the laser off when not in use and remove the key from the keyswitch of the laser power supply to
prevent unauthorised activation.
ALWAYS thoroughly inspect the LIBS equipment for damage prior to use. Particular attention should be given to the
laser safety windows and the laser safety interlock system, which should be tested each time the equipment is used.
NEVER allow unauthorised and/or untrained persons operate the LIBS equipment.
NEVER operate the LIBS equipment in areas where explosive gas mixtures may be present.
NEVER operate the LIBS equipment with any access cover, panel, or protective window removed.
NEVER place inside the sample chamber flammable liquids or any other material which may give rise to flammable /
explosive gas mixtures. Activation of the laser under these conditions could result in an explosion leading to severe
personal injury and/or fire hazard. Remember that the laser-induced plasma is a source of ignition.
NEVER point the LIBS laser beam at a person (even with laser switched off), especially towards the eyes, even if the
person is wearing laser safety eyewear. The laser should be considered “active” unless the laser power supply is
deactivated and the safety shutter fitted to the LIBSCAN 25+ head is switched to the CLOSED position.
NOTE that the transparent acrylic nozzle aperture of the LIBSCAN 25+ head does not provide any protection to the
user against exposure to direct or scattered laser radiation. The function of the nozzle aperture is described later in
this User’s Manual.
CAD image of LIBSCAN 25+ head with laser safety shutter in the “closed” position.
Laser shutter / trigger guard
in “closed” position.
Orange warning light not
illuminated
Trigger guard in “closed” position preventing
access to the trigger switch. When the laser
shutter is closed, the trigger switch is
electrically isolated and so the laser will not fire
even if the trigger switch is activated. The laser
shutter provides a mechanical beam stop which
prevents emission of laser radiation under any
circumstances, including a fault condition.
Laser aperture
warning label
Laser aperture

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CAD image of LIBSCAN 25+ head with laser safety shutter in the “open” position.
2.2 Note on the laser safety window material used in the modular sample chambers
The laser safety window material fitted to the modular sample chambers is rated as follows:
Laser
Wavelength
(nm)
USA Standard
ANSI Z 136.1 –2014
UK & European Standard
BS EN 207:2017
Optical
Density
Protection Level R
(Q-switched laser)
1064
OD 6
L6
355
OD 5
L5
266
OD 3
L3
R L6 at 1064 nm indicates a protection level of maximum spectral transmittance of 10-6 at 1064 nm for a
pulsed laser of pulse length 10-9 –10-7 seconds (ie. a Q-switched laser).
The laser safety windows used in Applied Photonics Ltd’s range of modular sample chambers provide
adequate protection against scattered laser light of wavelength 1064 nm, 355 nm and 266 nm such that
Class 1 Accessible Emission Limits are met if the sample chamber is used correctly and laser pulse
energies are not excessively high (ie. typically less than 300 mJ with a 5 - 10 ns pulse length). Note that
the protective windows are NOT suitable for use with a 532 nm laser. Given that the modular sample
chambers may be used with a variety of APL’s LIBS products, it is the responsibility of the user to
conduct a risk assessment to establish whether or not the laser safety windows provide adequate
protection for the particular laser being used. If in any doubt, you should consult your Laser Safety
Officer and/or Applied Photonics Ltd for advice on this matter.
Warning –the Applied Photonics Ltd modular sample chambers are designed specifically for use
with our LIBSCAN (and our LIBS-6 / LIBS-8 integrated LIBS modules) range of products and
should not be used with any other laser device or product. If in doubt, seek advice from the
manufacturer, Applied Photonics Ltd.
Laser shutter / trigger guard in “open”
position. Orange warning light now
illuminated (assuming laser is active)
Trigger guard in the
“open” position allowing
access to the trigger switch

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2.3 Electrical
The majority of internal electrical components within the LIBSCAN 25+ instrument operate at a nominal
voltage of 12 VDC at a maximum current of approximately 3.0 Amp. The integrated laser and associated
power supply operate at voltages of up to 1000 VDC. Accordingly, there exists an electric shock risk
should the equipment be dismantled. There are no user serviceable components within the LIBSCAN
25+ instrument and so the equipment should not be dismantled (doing so will void the warranty and
expose the user to an electrical and/or laser radiation hazard). For servicing and repairs, the equipment
should be returned to the manufacturer or an authorised agent.

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3 General description
3.1 Overview
The main components of LIBSCAN 25+ are illustrated in the following figure.
CAD image illustrating the main components of the LIBSCAN 25+ instrument
The instrument console contains the optical spectrometers (up to six spectrometers may be installed), the
laser power supply, the Li-Ion battery, and various electrical / electronic components. The LIBSCAN
25+ head contains the laser, the laser beam expander optics, the plasma light collection optics, a miniature
colour video camera (optional item) and various other components associated with the safe operation of
the equipment. The LIBSCAN 25+ head is permanently connected to the instrument console via a
flexible umbilical of length ~1.6 metres. The umbilical contains the optical fibres used to transmit the
plasma light to the spectrometers, and the electrical cabling for the laser and other electrical components
within the head. The control panel provides the various switches and electrical connections associated
with the operation of the instrument.
Instrument
console
LIBSCAN 25+
head
Control panel
Flexible
umbilical
Li-Ion battery
charge status
indicator

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3.2 LIBSCAN 25+ instrument console
Main “Power On” switch –
central indicator light flashes
when unit is connected to
mains charger
Laser key
switch (key
not shown)
“INTLK IN” BNC for
connection to laboratory door
interlock device. Blanking cap
(shown fitted) used if this
feature is not required
Spectrometer / laser
trigger sync
(BNC connector)
Laser flashlamp
voltage adjust
Inert gas inlet port
(requires 4 mm OD
plastic tubing) for gas-
purge of sample
“INTLK OUT” BNC
connection –provides 12
VDC output when laser is
active
Laser Interlock Override
keyswitch (for operation
as a Class 4 laser product)
USB 2.0
connection
DC power input from
plug-in Li-Ion battery
charger
Trigger input BNC to
remotely fire the laser
(requires > 0.1 millisecond
pulse of 9 –12 VDC,
centre pin +ve)
Power On
indicator lamp
Main Fuse
3A
Fuse panel
cover
Laser On
indicator
lamp
Battery fuse 1
(3A anti-surge)
Battery fuse 2
3A anti-surge
Laser pulse counter

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3.3 LIBSCAN 25+ head
The LIBSCAN head contains the laser and associated optics required to focus the laser beam on to a
sample and collect the plasma light for transmission to the spectrometers located within the spectrometer
console. The head is also designed to accommodate a miniature CCD camera and associated components
used with the optional imaging kit. The main features of the LIBSCAN head fitted with the optional
imaging kit are illustrated in the following figures. Use of the transparent aperture nozzle allows the
operator to view the laser plasma even when a sample is placed up against the aperture.
WARNING: Note that the transparent aperture nozzle does NOT provide any protection to the
user against exposure to the laser radiation.
It is not necessary to have an aperture nozzle fitted to the LIBSCAN head although it is beneficial to do
so as it provides the following functions: i) facilitates correct positioning of the sample being analysed, ii)
helps to direct the purge gas (if used) to the region in space where the laser plasma will be formed, and
iii) provides protection for the optics etc against accidental mechanical damage.
LIBSCAN 25+ head with aperture nozzle removed LIBSCAN 25+ head with transparent aperture nozzle fitted
Front view of LIBSCAN 25+ head showing six-channel plasma light collection lens array,
CCD camera, LED lights, laser aperture and gas purge outlet
Grub screw for locking
transparent aperture nozzle
(do not over-tighten)
Circular array of six
lens holders –used to
collect plasma light.
The purple lens holder
is for collection of
deep UV. The blue
lens holders are for
collection of UV-VIS
while the red lens
holders are for
collection of VIS-NIR
Laser beam
expander and
output aperture
Transparent
aperture nozzle
Miniature CCD
camera
(optional feature)
Two high-
brightness white
LED lights
(optional feature)
Gas purge
outlet
Electrical connection
to modular sample
chamber