Conventional night vision systems
improve the user’s ability to "see"
objects by enhancing visible light.
These systems only work if there is at
least a minimal amount of available
light and if there is nothing obscuring
visibility (such as dust, haze, fog, or
smoke). FLIR IR cameras are still highly
effective under conditions of
low-visibility or complete darkness. By
providing an image of the infrared
energy being emitted by objects, the
system can still "see" in complete
darkness or obscured visibility. While
the effectiveness of the system may be
diminished when viewing distant objects
under obscured conditions, FLIR infrared
cameras still provide better visibility
than other night vision enhancement
systems. Because it measures thermal
energy, FLIR infrared cameras can be
used to conduct surveillance without
relying on search lights or special
lighting, improving the user’s ability
to remain undetected.
The military advantages of these early
systems were significant. Naval vessels
could still detect and target enemy
ships, even on the darkest nights or
under foggy conditions. As one might
imagine, these early systems were large,
heavy, and expensive. During the past
decades, however, FLIR thermography
cameras have been adapted for use aboard
all types of aircraft, naval vessels,
and ground vehicles; in recent years
some manufacturers have even developed
handheld units. Technological advances
have significantly lowered the size,
weight, and cost of FLIR sights. These
new systems may offer reliable service
without requiring extensive or costly
upkeep.
Handheld FLIR scopes weight less than
five pounds and may be within the price
range of many law enforcement agencies.
LAW ENFORCEMENT APPLICATIONS
FLIR infrared imaging cameras have been
successfully used by a number of major
law enforcement agencies in recent
years. Until recently, FLIR cameras has
generally been a tool for aviation
units. Mounted on a helicopter, a FLIR
binocular or digital goggle fusion
camera could assist in pursuits and
Search and Rescue missions. The systems
were still expensive and somewhat
cumbersome. Because aviation units were
most likely to respond to situations
where FLIR imagers could be of use, this
was a logical use of this resource.
More recently, law enforcement agencies
have begun experimenting with FLIR
infrared cameras mounted on ground
vehicles or as independent, handheld
units. Lubbock, Texas, has FLIR infrared
imaging cameras integrated into their
canine vehicles. A canine vehicle is
likely to become involved in search or
pursuit operations, so deploying ground
vehicle systems with these units makes
sense. As technologies improve and costs
continue to decrease, it may be more
common to see ground vehicle mounted or
handheld FLIR infrared cameras being
used to support a wide variety of law
enforcement applications. As a tool to
assist in either pursuits or Search and
Rescue missions, FLIR infrared thermal
cameras offers several advantages to
police organizations. While it was
designed for use during operations
taking place at night or under obscured
visibility conditions, FLIR thermal
imagers can also be used during day
light hours. For example, a search for a
missing child or a fleeing suspect might
lead to a farm field. Depending on the
nature and density of the foliage, an
aviation unit equipped with FLIR IR
thermography cameras might be able to
locate a child or suspect who might
otherwise be hidden from plain view,
even during daylight hours.
Many FLIR thermal infrared imaging
cameras are designed to videotape what
the operator sees. In addition, units
may also serve as daylight video
recording systems. These features allow
officers to generate evidence which
might be very helpful in prosecution.
For example, a helicopter equipped with
FLIR sensor could assist ground vehicles
in a high-speed pursuit of a stolen
automobile. As soon as the helicopter
arrived in the area of the pursuit, it
could begin to record the events
occurring on the ground. The system
could videotape the infrared image of
the driver "bailing" from the vehicle
and fleeing into a residential
neighborhood. The system could continue
to videotape the suspect as he fled
through backyards and assist aviation
personnel in directing officers on the
ground in order to make an apprehension.
Having the chase on tape would provide
incontrovertible proof that the suspect
taken into custody was indeed the driver
of the stolen vehicle (and not an
innocent citizen "looking for a runaway
cat"). Because the system is not
dependent on the use of a search light
(which might produce shadows and
distortions on a videotape), it might
also show that officers used appropriate
force in taking a suspect into custody,
thus limiting potential liability.
FLIR thermal infrared imaging cameras
may be one of the best options for
vision enhancement under conditions of
obscured visibility. Some jurisdictions
frequently encounter problems due to fog
or haze. Vision systems which amplify
available light may be less effective
under such conditions. While FLIR does
have a limited ability to penetrate
smoke, dust, haze, or fog, it is
generally more effective than the naked
eye or conventional night vision
enhancement systems under such
conditions. Police marine units may be
find it easier to engage in routine
patrol or search and rescue operations
with a FLIR thermography imaging camera,
even under conditions of heavy fog (and
even during daylight hours). Fire
departments have been using
helmet-mounted FLIR goggles or hand held
binoculars for several years to aid
personnel in searching for victims in
fires. Although FLIR binoculars cameras
cannot penetrate all of the smoke
generated by a burning building, it can
improve a fire fighter’s ability to
"see." These systems not only allow fire
fighters to conduct a more thorough
search in less time, but a search could
be done with fewer personnel, placing
fewer lives at risk in the performance
of dangerous operations. FLIR binoculars
can also be a valuable tool for police
personnel conducting surveillance or
security operations.
Because the system works without relying
on light sources, it can be operated in
a covert manner. Personnel scanning a
dark parking lot could observe potential
victims or suspects without alerting
these party’s to their presence.
Individuals can be clearly seen, even
under conditions of complete darkness.
These unique thermal infrared night
vision applications might enhance to
covert nature of surveillance
operations and decrease the number of
personnel required to conduct such an
operation.
FLIR sights, scopes, binoculars, goggles
and cameras may also be used to take
digital thermal image of a person,
luggage, buildings, automobiles, trucks,
or boats (generally in an effort to
search for drugs). While FLIR binoculars
or goggles can not see through walls or
doors, they can detect temperature
differences which might indicate the
presence of hidden compartments or
contraband. A thermography scan may
indicate if a person has something
secreted beneath their clothing, or if
the hold of a ship contains ice-cold
fish or something with an even greater
street value. Growing marijuana indoors
requires the use of high-temperature
artificial lighting; a thermal scan of a
neighborhood might indicate if a
specific house has an unusual hot spot
which might indicate that such indoor
gardening is taking place.
It must be noted that the courts have
not fully resolved how police officers
can use thermal images in carrying out
drug or contraband detection. Some
federal circuit courts have viewed
thermal imaging as equivalent to any
other search.
As such, police officers in these
circuits may need either explicit
probably cause or a search warrant in
order to use thermal imaging. Other
circuits have taken a more liberal
stance, allowing law enforcement
personnel to engage in random thermal
imaging. Readers would be well advised
to check the status of FLIR imaging as a
search within their state and federal
district courts before undertaking such
operations.
INCREASED EFFICIENCY WITH FLIR
newer digital compact FLIR binoculars
and goggles with increased sensitivity
and smaller micron pitch offer a clear
way for law enforcement agencies and
military professionals to operate in a
more efficient and effective manner. As
a tool for an aviation unit, FLIR
thermal infrared imagers can
significantly reduce the time needed to
conduct a search. Agencies using FLIR
infrared imaging cameras might also have
an easier time tracking and apprehending
fleeing suspects. FLIR infrared cameras
make pursuit and search operations more
efficient and also safer.
Suspects or victims can be quickly
located. Officers on the ground can be
directed to these locations without
conducting prolonged, and potentially
dangerous, searches.
As a surveillance tool, FLIR thermal
infrared imaging cameras may allow
agencies to carry out some operations
with fewer personnel and in a more
covert manner. Officers can covertly
scan areas, even under complete
darkness. Under some conditions, FLIR
infrared cameras may also allows users
to detect well camouflaged individuals.
Because many FLIR imagers allow for the
generation of video recordings, it is
easy to produce evidence suitable for
use in the courtroom. Such evidence may
enhance the likelihood of prosecuting
defendants in cases where the cover of
night might have otherwise made suspect
identification difficult.
Newer digital compact Thermal FLIR
handheld cameras are being utilized in
the commercial marketplace for
applications such as electrical and
mechanical thermography, printed circuit
board or PBC analysis, energy audits,
roofing, home inspections, water
restoration, insulation audits, medical
infrared imaging, data center, integrity
and condition monitoring needs. FLIR
thermal imaging is an emerging
marketplace.
The use of FLIR technology can
allow for agencies to conduct certain
operations with fewer personnel. In
addition, those personnel involved in
such missions might be able to perform
their duties with an enhanced degree of
safety and security. The current cost
FLIR systems may preclude some law
enforcement agencies from enjoying these
benefits. Despite the current cost of
FLIR systems, it is likely that
purchasing and maintenance costs will
continue to decline, while performance
improves in the years to come.