Night has fallen and we have the technology to see in the dark. Last Friday we took a look at the French-made Thales LUCIE low profile night vision goggle. This week we take a look at another piece of military hardware. The SAFRAN JIM LR is a cooled thermal biocular that has a built-in SWIR laser range finder and IR pointer. It also has a built-in GPS. Let’s take a look at this cool thermal device, pun intended.
JIM LR Bioculars
The JIM LR can be found under a couple different company names: Safran, Sagem, and Vectronix. In the US, the unit is called the LRTV (Long Range Thermal Video). JIM LR is an acronym in French, Jumelle Infrarouge Multifonction-Long Range. Which translates to Multifunction Infrared Binocular. However, the JIM LR is not a true binocular. It is a biocular. It only has a single image that is duplicated into both eyes like the Thales LUCIE or a PVS-7. If it was truly binocular, then it would need two distinct thermal images and when you look through them you would get stereopsis like my dual SKEETIR-L binos. That being said, the JIM LR has a lot of functions beyond just a thermal spotter.
As I mentioned earlier, the JIM LR laser range finder is a SWIR LRF. Like other military laser range finders for dismounted soldiers, this LRF emits in the SWIR wavelength. It operates at 1500 nM. This is far outside the operating range of analog night vision. Even with Photonis that can see up to 1100 nM it cannot see this LRF pulse. Full spectrum CCD sensors can see up to 1400 nM but even the SWIR LRF is out of the band for digital cameras. SWIR lasers are actually eye-safe while still being powerful to range out far. According to SAFRAN, the JIM LR can range up to 10 kilometers (10,000 meters). I was able to range out to 11,080 meters in broad daylight, which is 6.88 miles away. See the photo below, the mountain top in the background is what I was ranging.
You hold the JIM LR like a giant pair of binoculars. The right-hand side has a hand strap and a button for your right-hand thumb. This button engages the laser range finder. Once engaged, you tap it again to fire the laser range finder. I was able to range out that mountain top and it was almost instantaneous. Maybe about a second and the JIM LR gave me the distance.
There is an option in the JIM LR to switch to the IR pointer. This is for designating targets or objects of interest to someone else who has night vision. There are two versions according to SAFRAN’s brochures: a 0.4mW and a full power 15mW version.
There are rubber covers for the LRF front end and a separate rubber cover for the thermal objective.
Somewhat like a Nintendo Virtual Boy, the JIM LR has a rubber eye shield/mask to block the light emitted from the LCD screens inside from leaking out. This also blocks sunlight from getting between the screens and your eyes.
On top of the JIM LR, there are four buttons. Left side you have the backtrack button and validation button. The buttons on the right-hand side are for selecting options. The large black bump is the GPS antennae.
With the JIM LR at rest, the right buttons will adjust focus. At rest, you can press the backtrack button and it will switch to the next function option. There are 6 functions. Pressing the backtrack button a seventh time will cycle back to the first option, focus adjustment. The six other functions are as follows: zoom, picture/video, Freeze image/IR TV Day Channel, Calibrate IR/Polarity, brightness and contrast.
At the back of the JIM LR, just below and to the right of the eye mask are two connectors. One of them is for connecting a DAGR for better GPS functionality. The other is for power and video out. There are other uses like data transfer.
To turn on the JIM LR, the power button is on the bottom underneath the unit.
Powering The JIM LR
The JIM LR is powered by a BT-70582 or BT-70747 battery. The 70582 battery is also known as ALI-142 or BT-70483. The BT-70747 battery is also known as a BT-2847A/U. The battery is held in place with a nylon strap.
One end is hooked onto this curved piece of metal.
The other end of the nylon strap is bolted into place on this cam latch. You turn the cam to tighten the strap and hold the battery in place.
The strap works but it is too easy for the strap to slide down and off the battery. As soon as the battery loses connectivity to the contacts, the JIM LR shuts off.
I found this photo of an LRTV off ZIB Miltaria’s website. It is long since sold but it shows a different style battery holder. It looks like a metal cage with a hinged door.
I decided to try and make a bracket to hold the battery in place. I used angled aluminum, cut it, and folded it into a shape that could hold the battery in place. I need to redo it as the dimensions are a little off. It causes too much pressure on the outside of the battery thus causing the battery to sit at an angle. It is easy for the JIM LR to disconnect for a moment and shut off.
Using The JIM LR
This is a cooled thermal system so it has a cool down time of about 6-8 minutes. There is a loud whirring sound when it does this. It is actively cooling the sensor. There is some sort of mechanical cooling that is happening. The benefit is greater sensitivity. During the 6-8 minutes to cool the sensor, you can use the day channel as well as the laser rangefinder. I posted this photo earlier but you can see the compass, GPS, and laser rangefinder work. They work as soon as the JIM LR turns on but it defaults to thermal mode so you need to manually switch it to day mode.
I also like to go into the menu and change the configuration so the display is on all the time. Once the sensor is sufficiently cooled down, the whirring sound is reduced a bit. You don’t hear if you are 15 ft or more away from the JIM LR. In thermal mode, there is a wide field of view (WFOV) and a narrow field of view (NFOV) as well as digital zoom. The WFOV and NFOV are switched by a physical lens. When you zoom in you can hear a motor moving inside. If you look into the thermal objective lens, you can see an element shifting forwards to you when it zooms in. Day mode starts in NFOV. It does not have a WFOV mode but you can use digital zoom.
Here is a video with some clips I shot with my iPhone. The whirring sound is the pump actively cooling the multi-stage processor.
In the video, I tested a Steiner Northstar MWIR beacon. It is tiny and runs off a single CR123. The black circle is where the MWIR signal emanates from.
The beacon has magnets built into the back embedded in the pocket clip. I stuck it to a street sign at the end of my street.
The JIM LR was able to see the MWIR beacon flash 682 meters away. Under normal uncooled LWIR thermal the strobe is only visible to about 25 feet.
Augmenting The JIM LR
One problem I have with the JIM LR is the day channel. It is a digital camera that is not very good at low light. In fact, it is unusable in low light. I was driving through Nevada at night and stopped at a scenic overlook. I pulled out the JIM LR to see at night using the thermal. I noticed some lights out in the distance but since thermal cannot see photons, it was difficult to aim the thermal lens to the spot where I saw the light. When I tried using the day channel it did not show the lights. So I checked the day channel and it starts at WFOV which equates to about 8x on my Vortex Razor 1-10x scope. Since the day channel video camera is at 8x, it should be able to see into my PVS-27. All I had to do was mount it in front of the digital video camera’s objective lens. I used a Larue SPOTR inverting rail, normally used on scope rings to invert a CNVD over the objective lens of your day scope.
I can switch between night vision enhanced digital video or cooled MWIR thermal imagery.
The bottom of the JIM LR has three threaded screw holes. I cut a sheet of steel and drilled holes so it would bolt onto the JIM LR. I then drilled holes to bolt on an arc plate and a segment of Picatinny rail. The Larue inverter rail mounts to the Picatinny rail and holds the PVS-27 in front. I added the ARCA plate but with the shorter ARCA plate on the Larue CNVD rail, it seems superfluous.
I revisited the same location with a mount for my iPhone and the near-full moon was out.
In the menu system, the JIM LR even has image stabilization in case you are holding the JIM LR and not using a tripod. However, this is only for observation. If you try to use the laser rangefinder then the image stabilization stops.
Final Thoughts On JIM LR
I picked this up in a trade but they normally fetch a very high price tag. Used ones go for around $20k-$30k. I have not found an MSRP price tag but I suspect it could be around $50k or more. This one has an instruction manual dated 2007 so while it is old, the performance is very good. I am sure the newer ones are even better.
Next on my project list is to make a more rigid platform for the JIM LR and the accessory rails for the night vision rail. I used a thin sheet of steel and while it helped me to realize my proof of concept with the night vision enhanced day channel, the thin sheet is flimsy. One problem is if I use a thicker material that will push the night vision rail even lower. I had to use a KDG sidelock riser on top of the night vision rail just to get the PVS-27 high enough to sit in front of the day channel objective lens.
There are some accessories mentioned in the user guide. Safran made afocal magnifiers for the JIM LR but more importantly, I want the video out/power cable. Then I can record the video from the JIM LR direct to a mini DVR rather than holding my iPhone up to the eyepiece and filming what it sees. Unfortunately, Vectronix has yet to respond to my inquiry to purchase this cable.
I am over the moon that the JIM LR is sensitive enough to see the thermal bullet wake off standard bullets. Seeing the bullet fly to 800 yards and splash on steel is fun and informative. My friends and I will revisit shooting long distance, past 1200 yards, and hope to use the JIM LR to help spot.