ILLUMINATION
Safety Features of the
Lasiris™ Magnum II Laser
Application Note
INTRODUCTION
asers produce intense, coherent and highly directional beams of light, therefore there are always risks associated with their use. Even the most experienced laser user can become careless, especially for those whose tasks are
repetitive in nature. It is important to remember that the risks are real and
that accidents can lead to non-reversible consequences. Ensuring that laser
users are up-to-date on their laser safety knowledge is essential to their well
being and to the well being of those around them.
L
The Lasiris™ Magnum II Laser is equipped with several protective features that
serve to minimize accidents in the work place. These features are listed on
page 3 of this document.
RISKS
Users should be aware of the risk factors associated with the lasers they operate:
Wavelength: Lasers can emit beams at various wavelengths (for machine
vision applications, typically between 0.1 and 1 µm) and certain ranges are
more dangerous than others. Lasers emitting beams in the near-UV and nearIR ranges are not easily visible by the naked eye, hence exposure to these
wavelengths poses potential health hazards that may not be initially evident.
Energy: The power density (irradiance) is an important factor in determining
risk. Laser light is partially absorbed upon contact, raising the temperature of
the surface and/or the interior of the object and therefore potentially deforming the material/tissue, especially at higher power output levels.
Lasers are classified according to the output power of the laser beam. The
higher the output power, the higher the risk for damage to the skin/eye.
Divergence: Depending on the type of beam divergence,
the associated risks vary. For instance, an unexpanded
collimated beam contains more power density than a
highly divergent beam viewed at a distance.
Duration of exposure: The risk of damage to the skin/eye
is directly proportional to the duration of the laser beam
exposure to these areas.
Improper usage of lasers, especially those classified as
Class IV, can lead to:
• Effects on the skin
• Electrical hazards
• Chemical contaminants
• Noise
• Ionizing radiation (high voltage power supplies)
• Explosions
• Fire
• By-products created by CO2 laser cutting
PREVENTION & PROTECTION
Here are some tips on how you can create a safe working
environment while operating a high power laser:
•
Never expose your eyes directly to a laser, even for
weak powers or short exposure times.
•
Wear protective eyewear adapted to the power
and wavelength of the laser; eyewear protection
is mandatory for Class IIIB and Class IV lasers.
Beware of lasers in the near-UV or near-IR which
often appear to be weak intensity visible lasers.
When working with these types of lasers, protective eyewear should be worn and the use of a
camera or another optical instrument should be
used to align laser optics. Remember, the temporary discomfort of wearing protective eyewear
outweighs the discomfort from permanent eye
damage.
•
Individuals who operate Class IIIB or IV lasers
should be properly trained. These laser classes
pose the highest degree of risk.
Photopic Luminous Efficacy
Hu ma n E y e S e n s i t i v i t y S p e c t r u m
1.2
1
0.8
0.6
0.4
0.2
0
250
450
650
850
Wavelength (nm)
Figure 1.1 - Luminous efficacy values gauge the relative sensitivity of
the human vision at any given visible wavelength, with respect to the
sensitivity at the wavelength of maximum sensitivity, around 555 nm
(green). Eye response to lasers that emit at wavelengths in the near-UV
(~250-350 nm) or near-IR (~800-900 nm) ranges is relatively low to
zero and therefore extreme caution should be exercised when operating
such lasers.
•
Avoid beams coming out of a setup by
using beam dumps, screens or curtains.
•
Enclose the beam’s path as much as possible to avoid direct exposure or reflection.
•
Post a sign outside your lab to indicate
the use of a laser.
It is important to note that glass has a reflectivity
of about 4% on each interface, and that these
reflections can be harmful from a high power
laser. Never wear rings, watches or bracelets when
operating a laser to avoid unwanted reflections.
There are several safety features that have been implemented into the Magnum laser:
1. Shutter: The protective cover at the front of the optical head can be used as a beam blocker if the laser is to
be left on.
2. I/O (on/off) Switch: The I/O toggle for the Main
Switch is located at the back of the laser. If the laser
operation is not required for your assembly procedures,
switch the laser to the off position in order to protect personnel from accidental beam exposure. The laser can be
re-activated by switching the toggle switch to the on
position.
3. Key Switch & Interlock Circuit features: Class
IIIB and Class IV lasers require the installation of a safety
mechanism to prevent exposure to the laser light. As such,
Magnum II lasers are equipped with a removable key and
an interlock circuit:
a. Key Switch: The laser will not operate and no laser light
can be emitted without the key switch in the on position.
Interlock System: When the interlock circuit is
opened, the laser will automatically shut off. For
example, one can connect the pins of a door contact
switch to a 1/8" connector. Plug this connector into
the 1/8" Interlock of the laser. Whenever the door is
opened (thus opening the interlock circuit), the laser
will automatically turn off.
4. Manual Reset option: In the case of Class IV
Magnum II Lasers, the laser will shut down and a
manual reset is required whenever the laser undergoes
an unexpected loss of main electrical power for more
than 5 seconds, or if the interlock circuit is interrupted
(see above).
5. Non-Gaussian Profile of Beam: With conventional Gaussian line generators, it is generally the hot
central spot that causes its safety rating to go up one
class (e.g., from CDRH Class II to IIIA). Our patented
optics produce a line of uniform intensity that does
not have a hot spot at the center. Therefore, a Lasiris
non-Gaussian laser can offer a safer level of exposure,
in addition to more light and uniform illumination
transmitted to your application.
1.0
b. Interlock Circuit: The 1/8" connector on the back of the
laser is an interlock connector.
1.0
0.8
0.6
0.4
0.2
0
0.8
0.6
0.4
0.2
0
-10 -8 -6 -4 -2
0
2
4
6
8
10
-10 -8 -6 -4 -2
Relative Angular Position
6. Safety label: Magnum II Lasers are classified
according to the output power and the wavelength of
a laser beam in a particular setup according to the
United States Center for Devices & Radiological Health
(CDRH) document 21 CFR 1040.10, and, upon demand,
to the International Electrotechnical Commission (IEC)
document 60825-1: version 1.2 2001-08.
Information and specifications contained herein are deemed to be reliable and accurate. StockerYale reserves the right to change these specifications at any time without notice.
1-800-814-9552
StockerYale Inc.
275 Kesmark
Montreal, Quebec
Canada H9B 3J1
Tel.: (514) 685-1005 Fax: (514) 685-3307
www.stockeryale.com/lasers
lasers@stockeryale.com
01/06 - AN-MAG2-003
StockerYale’s Lasiris™ Magnum II Laser is a high power
line generator developed for the most demanding industrial applications. Diode powers range from 250 mW up to 4
W.
General Use: The Magnum II Laser is shipped with a
shorted 1/8" jack which is simply plugged into the
interlock connector for normal laser operation. When
the shorted jack is removed from the interlock connector, the laser will automatically shut off.
Relative Intensity
THE
Relative Intensity
SAFETY FEATURES OF
MAGNUM II LASER
For international distributors,
call us or visit:
www.stockeryale.com/laser_distributors
Relative A