Seeing in total darkness in a maritime environment

Seeing in total darkness in a maritime environment
application
story
Seeing in total darkness
in a maritime environment
The advantages of thermal imaging
Practically all of us associate the sea with holidays and fun, but it can be a dangerous place,
especially in nighttime and bad weather. Yachts collide with other vessels, run on cliffs or other
objects resulting in heavy damages and sometimes even loss of life. Some of these accidents
happen in open water, others while navigating in harbors and ports.
Our eyes are the first line of defense against these
hazards. Unfortunately, eyes are not the best detectors
at night or in bad weather. Any accident at sea does
not only have severe consequences for the vessel
but also for its passengers and crew. A number of
tools are available to help us detect potential dangers
before they become a real hazard.
Thermal imaging:
an excellent tool to help you see at night
One of these tools is thermal imaging. Thermal imaging
is the use of an infrared camera to “see” thermal energy
emitted from an object. Infrared energy can not
be detected by the eye because the energy of the
photons is too low to stimulate the photoreceptors
in the eye. Also, thermal IR light does not get to the
retina, because it is highly absorbed by the eye’s lens
and fluids. Infrared allows us to see what our eyes
cannot - invisible heat radiation emitted by all objects
regardless of lighting conditions. Thermal imaging
cameras produce images of invisible infrared or “heat”
radiation. Based on temperature differences between
objects, thermal imaging produces a clear image.
Bridge in total darkness
Thermal imagers are very effective in marine
environments. They can detect objects floating in
the water which may damage a vessel, or even
worse, sink it. Other vessels, shipping lane traffic,
buoys, bridges, ... it is all seamlessly detected by
thermal imaging.
Although there are other technologies available
for helping you to navigate during the night and
to help you prevent catastrophes, thermal imaging
outperforms them, has some advantages over them
or it can complement them.
Thermal image of the bridge in total darkness. Even up to several
kilometers away, seeing threats is an easy task for thermal imaging
cameras.
COMMERCIAL VISION SYSTEMS
application
story
Several types of lights serve as navigational aids at
night. But even when all boats have proper lighting,
it’s very difficult to judge bearings and closure rates.
But when boats have improper lighting, like a lot of
them do, ... well, you don’t really have a chance of
avoiding an accident. Furthermore, navigation lights
become less useful when fog or rain is obstructing
your view. You might see an approaching vessel too
late which can lead to lethal accidents.
Thermal imaging can see through light fog and haze.
Although the distance a thermal imager can see is
also obstructed by light fog and haze, it will give
you a clear warning of an approaching vessel, in all
weather conditions.
Visualize RADAR blips
RADAR, the abbreviation of RAdio Detection And
Ranging is, a system that uses reflected radio waves
to determine and map the location, direction, and/or
speed of both moving and fixed objects. The first
commercial RADAR systems were developed during
the 1940’s and today they are installed on practically
every yacht.
The limitation of RADAR is that it only gives you
a small blip on the screen when it is detecting an
object. A thermal imager will give you a real image of
the situation. This will help you to determine whether
a certain object is a real danger or not.
does require a certain level of ambient light, but even
starlight can produce an image on a cloudless night.
A high-end image intensified camera can produce
outstanding images on a clear moonlit night.
Because the system requires at least a minimum
level of ambient light, conditions such as heavy
overcast can limit its effectiveness. Similarly, too
much light may overwhelm the system and reduce
its effectiveness. Imagine yourself navigating in a
harbor with the lights of the marina, or the skyline
of a city, in the background. These lights will also be
amplified and you will be totally blinded.
Contrary to light amplification systems, thermal
imaging works by detecting the heat energy being
radiated. It needs no light at all and produces a clear
image in the darkest environments.
Visual image
Night Vision goggle
Thermal image
Low-lux cameras
The light requirements to produce an image are
measured in lux. The lux is the rating for how well
the camera sees in low lighting conditions. The
smaller the number, the less light the camera needs
to produce an image and the better the ability to see
in the dark. Low-lux cameras provide an image in an
environment that is too bright for light intensification
equipment but still restricted by darkness. But do not
assume that if it is pitch black you can still see well
with a low lux camera.
Contrary to a thermal imaging camera, a low lux
camera will not produce an image in total darkness.
Thermal imaging systems sometimes combine one
or more thermal imaging cameras with a low lux
camera. This gives you the ability to see during daylight and low-light conditions.
Low light image
Low light to no light comparison
Thermal imaging:
more than just night time navigation
Thermal imagers are excellent tools for short to
medium range threat detection. Today, more than
ever, shipboard security is important. Thermal
imaging allows you to see what is around you, even
at long ranges. You can monitor activity in port or
at anchor and see approaching vessels or people
without alerting them that they are being watched.
Another limitation of RADAR systems is that it fails
to pick up small objects. However, even objects that
cannot be detected by a RADAR system, such as sail
boats, wooden boats, floating debris, ... can cause
massive damage to your vessel.
Each year, numerous people die after falling
overboard and not being found fast enough. Finding
a person that has fallen overboard within the shortest
possible time-frame is of the utmost importance.
Not only can the person float away from the vessel
but hypothermia is an important factor to take into
account. Thermal imaging can help find a person in
the water before it is too late.
Light amplification
Light amplification, also referred to as I2 technology,
amplifies small amounts of visible light thousands
of times so that objects can be seen at night. These
systems scan an area and amplify the available
ambient light to produce an image. Light amplification
Thermal cameras work during the day as well, and
give users the ability to see through marine haze more
effectively than with the unaided eye. It is not affected
by glare from the sun. Thermal imaging allows you to
see through the glare, and detect possible obstacles,
when navigating during sunrise or sunset.
Thermal image
If you would like more information about thermal
imaging and how it can protect your vessel and
its crew, please contact:
FLIR Commercial Vision Systems B.V.
Charles Petitweg 21
4847 NW Teteringen - Breda
The Netherlands
Phone : +31 (0) 765 79 41 94
Fax : +31 (0) 765 79 41 99
e-mail : [email protected]
www.flir.com
AS_1108_0006_EN
Navigation lights
The oldest anti-collision systems on ships are lights. In
ancient times, sailors would maintain small open fires
on deck in order to be spotted by other vessels. Later
these fires were replaced by electrical navigation
lights.
Was this manual useful for you? yes no
Thank you for your participation!

* Your assessment is very important for improving the work of artificial intelligence, which forms the content of this project

Download PDF

advertisement