Police Tech & Gear
with Tim Dees
Ground-based infrared gear for cops
These purchases can be easily justified to your community, and there are perfectly workable solutions available in the $2,000-$4,000 range
Most of us have seen the footage captured from infrared (IR) cameras mounted on police helicopters, where the airborne observer directs a cop on foot to the precise location of a hiding suspect.
The suspect, under the cover of darkness, thinks he is invisible and is only waiting for the cops to get tired and leave.
Boy, is he surprised. The only thing better is watching a K9 do the same trick with his nose.
Bringing IR Down to Earth
Infrared cameras are all but standard installations on law enforcement aircraft, and with good reason. They can use the benefit of the high vantage point to search for that which would otherwise be invisible. Unfortunately, most cops don’t have airborne resources to rely on, and even fewer have IR cameras available to them in the field.
Like most technology, IR cameras — also called thermal imagers — have become less expensive as the tech matures and gets more exposure in the market. You can lay out $10,000 and more for an IR device, but there are also perfectly-workable solutions available in the $2,000-$4,000 range. Homeland security and other similar federal grants will often pay for these.
Finding bad guys is the obvious use, but you may find yourself using the camera more for searches of lost children and senior citizens who have wandered away from home. Now that we’re in the winter months, these victims are that much more vulnerable to the elements, as their bodies may not handle temperature extremes as well as healthy adults.
Alzheimer’s disease victims in particular are prone to wandering off in their pajamas, unable to provide for their own needs or assist in the search.
I was involved in more than one search like this.
In one case, a male Alzheimer’s patient got out of his house, headed for parts unknown. He was dressed only in his underwear, with an air temperature of about +15° F. I and four other officers were trying to find him, and we were getting frustrated.
On a pass by his house, I saw some movement by the side of a house about four doors down. He had lain down on the grass and was barely visible from the street. I saw him only because he had raised his head slightly on seeing my headlights. We saved that one, but the task would have gone a lot faster with an IR camera.
IR devices come in two principal flavors: active and passive. Active IR uses a spotlight to illuminate the field of view, but the illumination is visible only when viewed through a special filter. Bare eyes will perceive a faint red glow from the IR lamp, but with the lens filters, the wearer will see anything under the light as clear as if it were lit up with a conventional spotlight.
The more common variety in law enforcement is passive IR, which detects small differences in temperature. In a cold environment, people and animals shine as if they are lit from within. You can look at the cars parked on a street or in a parking lot, and immediately know which one is still warm. Even footprints on the ground are visible for a short time until the surface returns to the ambient temperature.
A couple of years back, I had the opportunity to do a field test of a handheld IR camera from FLIR.
The unit was about the size of a large pair of binoculars and ran on rechargeable batteries. In complete darkness, my black dog stood out as if he was luminous. A wood post where I had rested my hand for a few seconds still bore a ghostly imprint.
I could look at the roofs of my neighbors and tell where they needed to beef up their attic insulation. The device also had the ability to save digital images onto an internal storage card that would download onto any computer.
The device costs about $5,000.
A different approach is used by NOPTIC. Their camera mounts on the top of the patrol car spotlight, with the output viewed on a separate digital display or on the in-car computer display.
NOPTIC claims that having the camera readily available, instead of in the car’s trunk, leads to greater use. Officers will check parking lots and closed businesses for heat signatures that would otherwise go unnoticed. There is also the advantage of being able to light up whatever the user is seeing on the IR screen with the white light spotlight, as they’re mounted coaxially.
The typical NOPTIC installation runs about $4,000.
Some critics complain that thermal imagers will be used by the police to spy on the interiors of buildings. That works a lot better in the movies than in real life. It might be possible to see that one portion of a building was warmer than another, but no one is going to see silhouettes of people walking around. Glass reflects IR, and appears black on the camera display.
Most agencies are looking for ways to extend their patrol force, and nearly everyone is dealing with more lost senior citizens as the mean age of the population increases. This is an equipment acquisition that may be easier than others to justify to the folks holding the purse strings.