10 Best Thermal Monoculars to Buy in 2020 [Reviews & Guide]


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Thermal monoculars are standard technological devices which detect very minute differences in the heat to produce an image.

Roughly, we know that monoculars are very much similar to a camera and an ocular gadget that uses the visible light in front of it to capture the scene but the difference here is, thermal monocular works by detecting the heat signatures using thermal imaging technology.

This technology is used in heat vision cameras or thermographic camera that has been often used by the police and military.

Best value
Pulsar Axion Key XM30 2.4-9.6x24 Thermal Monocular Black,...
Best Overall
ATN OTS-HD 640 5-50x, 640x480, 100 mm, Thermal Monocular...
Best Price
FLIR Scout TK Handheld Thermal Imaging Monocular
Pulsar Axion Key XM30 2.4-9.6x24 Thermal Monocular Black,...
ATN OTS-HD 640 5-50x, 640x480, 100 mm, Thermal Monocular...
FLIR Scout TK Handheld Thermal Imaging Monocular
  • 320×240 Sensor
  • 1,300-yard Detection
  • IPX7 waterproof
  • 320×240 Sensor
  • 1,300-yard Detection
  • IPX7 waterproof
  • 320×240 Sensor
  • 1,300-yard Detection
  • IPX7 waterproof
Best value
Pulsar Axion Key XM30 2.4-9.6x24 Thermal Monocular Black,...
Pulsar Axion Key XM30 2.4-9.6x24 Thermal Monocular Black,...
  • 320×240 Sensor
  • 1,300-yard Detection
  • IPX7 waterproof
Best Overall
ATN OTS-HD 640 5-50x, 640x480, 100 mm, Thermal Monocular...
ATN OTS-HD 640 5-50x, 640x480, 100 mm, Thermal Monocular...
  • 320×240 Sensor
  • 1,300-yard Detection
  • IPX7 waterproof
Best Price
FLIR Scout TK Handheld Thermal Imaging Monocular
FLIR Scout TK Handheld Thermal Imaging Monocular
  • 320×240 Sensor
  • 1,300-yard Detection
  • IPX7 waterproof
thermal monocular test
The image was taken on Sept. 9, 2013, Alaska when Army Spc. Nicholas Kuefler tests mini thermal monocular, night vision optic lenses before a combat training parachute insertion on Joint Base Elmendorf-Richardson. (Source)

Thermal Imaging Monoculars

Usually monocular can sense the heat radiations at the range of -50° C to 2000° C.

The thermal monoculars are used in firefighting where the firefighters use it to check if any injured persons lying fainted beneath the debris, doors, damaged walls, etc. and rescue them as fast as possible.

In the case of hunting, many farm fields have been invaded by wild hogs and boars at night but, guards would not be able to see at night so, they have no yields at last.

By using thermal monoculars, guards can effectively control the invasion of these wild animals on their farm fields.

Moreover, thermal monoculars extensively used in military, surveillance, energy analysis, satellite imaging, weather reporting, and all search and rescue operations.

Table: Best 10 Thermal Monoculars of 2020

ATN-OTS-HD-640-Thermal-Smart-HD-MonocularsATN OTS- Thermal Smart HD 640 Monoculars3D Gyroscope5/5
Pulsar-Helion-XP-Thermal-MonocularPulsar Helion XP Thermal MonocularStream Vision App4.9/5
ATN-OTS-HD-384-Thermal-Smart-HD-MonocularsATN OTS-HD 384 Thermal Smart HD MonocularsE-Zooming4.9/5
pulsar-axion-xm30-monocularPulsar Axion Key XM30 Monoculars1,300 yard Detection4.8/5
FLIR-Scout-TK-Pocket-Sized-Thermal-MonocularFLIR Scout TK Pocket-Sized Thermal MonocularQuick User Controls4.8/5
FLIR-Breach-PTQ136-Thermal-Imaging-MonocularFLIR Breach PTQ136 Thermal Imaging MonocularWeigh 210 g4.7/5
Leupold-LTO-Tracker-ThermalLeupold LTO Tracker Thermal Monocular6X Zoom4.7/5
bestguarder-hd-digital-nv-monocularBest Guarder Digital Night Vision MonocularIn-built Microphone4.7/5
Armasight-Spark-Night-Vision-MonocularArmasight Multi-Purpose Spark Thermal MonocularDouble Resolution4.6/5
Scout-III-240-Thermal-ImagerFLIR Scout III-240 Thermal Imaging Monocular350 m Detection4.5/5

Best Thermal Monoculars: 10 Monoculars Reviewed

Here, the Best Thermal monoculars from various popular brands have reviewed and ranked.

1. ATN OTS – Thermal Smart HD 640 Monoculars

ATN OTS – Thermal Smart HD 640 Monocular is a fantastic and high-quality monocular that has the highest recommendations from the hunters and wildlife enthusiasts.

Its thermal sensor has a high-level resolution of 640 x 480 pixels which is the pixel rating of standard television.



Brand: ATN

Resolution: 640 X 480

Display: 1280 X 720

Image Quality: Clear

3D gyroscope and E-compass

The eminent thermal sensor used in this ATN OTS- Thermal Smart Monocular can detect even a minute temperature change and make you see in complete darkness with additional features like 3D gyroscope and E-compass.

Gyroscope is a device used to maintain a good stabilization with the ground and determine the inclination of the monocular to the ground.

The E- compass is an electronic compass that provides proper orientation with the earth’s magnetic field using a magnetometer sensor.

The E-compass can lead you in a proper direction which would be very helpful in navigating and exploring routes.

user about atn ots hd thermal monocular
A shooter used ATN OTS HD thermal monocular to sight his coyote prey and got a perfect shot.

Moreover this ATN OTS- Thermal Smart Monocular can provide soft and delicate zoom in facilities by simply pressing a button of the image with impressive clarity.


This product is a special gear for a trip with your friends which would bestow videos and photos with a very grand resolution besides, provides a good range of Wi-Fi streaming.

Using the upgraded Wi-Fi module in this product you can share the adventures you have done with the friend next to you.

It comes with the SD card which can store your elite experience without using a USB cable.

In-built Rangefinder

An inbuilt rangefinder can detect any target within no minute. So you no need to carry separate rangefinder to range the difference.

Design and Weight

The product weighs about 1.85 pounds which will be easy to carry and the dimensions of this monocular are 8.8 x 3.1 x 3.2 inches moreover adding geographical information to various social media is also possible using the geo-tagging technique.

Read full review of ATN OTS-HD 640 Thermal Monocular here.

Below, we have provided the comments and feedback from hunters or viewers who used the ATN OTS HD 640 Thermal Monocular.

A feedback of an OTS user on Reddit.atn ots 640 reddit

An ATN OTS HD 640 Thermal Imaging Monocular user shared his experience with the unit.

2. Pulsar Helion XP Thermal Monocular

Pulsar Helion XP Thermal Monocular is a highly recommended monocular for hunting and outdoor sports as it has advanced thermal features.

This thermal monocular is designed with a large and powerful 50mm lens. The magnification range for this Pulsar monocular is from 2.5x to 20x with the smooth zoom feature which means you will get the high-quality thermal images.



Brand: Pulsar

Resolution: 640 X 480

Display: 640 X 480

Image Quality: Clear

High-Resolution Sensor

The resolution of a thermal sensor in this thermal monocular is about 640×480 pixels. The Helion XP possessing the uncooled micro-bolometric matrix (640X480) at 17 µm so detailed thermal imaging is possible.

Built-in Video Recording

This Helion XP monocular has the built-in video recording option so capturing the images and video is effortless. The recorded and captured media files will be stored in internal memory and that can easily be transferred to your laptop or PC using Wi-Fi or the wired connection.

user about pulsar thermal monocular
A hunter shared his experience of using a Pulsar thermal monocular for hunting hog.

Detection Range

This Helion XP thermal imaging monocular/scope can detect the heat signatures of the object up to 1800 meters away and that is really big game size.

High Image Frequency

Pulsar Helion XP has a refresh rate of 50Hz so this monocular can provide a comfortable view even if you are in dynamic and rapid motion.


3. ATN OTS-HD 384 Thermal Smart HD Monoculars

The ATN OTS-HD 384 Thermal Smart HD monocular is the best choice for mountaineers and hikers. This device combines the thermal imaging abilities with the High Definition view. The advanced features in this monocular reduce the guessing and providing accurate data while hunting.



Brand: ATN

Resolution: 384 X 288

Display: 1280 X 720

Image Quality: Sharp

Obsidian core processor

This monocular has the ATN’s range of the thermal camera that has an OTS-HD Obsidian core processor.

This hi-tech processor offers the fast process and reduced lags in any conditions like reaching your prey and recording the complete task.

A single touch of a button is needed to control the most of the inbuilt functions of a monocular and these are light and compact to ease the game.

Sensor Resolution

You will receive the thermal imaging in this monocular with the HD resolution of 384X288 pixels.

Added with the feature of seeing through dark or in unsolicited conditions, this ATN monocular also adds an extra layer and details to provide a clear view.

Smart Rangefinder

OTS-HD monocular has a built-in smart rangefinder which helps to measure the distance from you to your prey accurately. The reticle in the device adjusts automatically to provide a clear view.

Once you know the exact distance and get a clear view of your target, using the E-Zoom feature you can narrow your focus on your target.

ATN has the Smooth Zoom feature that offers ultra-slow zooming and assists you in getting closer to your target without any lag.


Bluetooth and Wi-Fi

This ATN OTS HD 384 monocular has advanced connectivity features like Bluetooth and Wi-fi.

The device can be connected to the smartphone or tablet through the dedicated ATN Obsidian mobile application. So you can see your actions on the big screen.

Clarity Images

The video recording of this monocular has 1080p capacity. The 3D Gyroscope in this monocular offers great stability in view which provides the high quality and sharp footages when capturing on the move.

Read the detailed review of the ATN OTS HD 384 monocular here.

4. Pulsar Axion Key XM30 2.4-9.6×24 Thermal Monocular

Another fantastic product from Pulsar is the Pulsar Axion model. Like XP and Quantum series, its Axion series also has great models. We chose Axion Key XM30 from the series to review here.



Brand: Pulsar

Resolution: 320 X 240

Display: 960 X 720

Frame rate: 50 Hz

Detection and Sensor

Pulsar XM30 is one of a high-end thermal monocular, mainly designed for hunting. It has an excellent detection range of 1,300 yards. The thermal sensor comes with 320×240 pixels resolution and 12um pixel pitch core.


About housing, it has made of lightweight but rugged Magnesium Alloy to ensure rigidity.

It has a very compact size that can fit into one hand and a pocket with a global standard size. So the high portability makes it a perfect tool for spotting and scouting.

It has an LCOS display of 960×720 pixels resolution. 

Pulsar Axion Key XM30 monocular does not have Stream Vision Compatibility, and also it has less magnification in its class.

Color Palettes

With this Axion monocular, you can view in varying conditions using its eight color palettes. There are five modes, such as White Hot, Hot Black, Red Hot, Rainbow, and Ultramarine.

Magnification and Zoom

Axion has a high magnification range of 2.5x – 10x in its optics. Using the digital zoom, you can increase the magnification to get a clear view of your target. It has 4x digital zoom, continuous zoom, 2x, 4x stepped zoom, and picture-in-picture zoom.

Image and Video

It has built-in video recording features. With one press on the REC button, you can start recording the footage and video. Its 16 GB internal memory allows you to record video for many hours and capture hundreds of photos.

5. FLIR Scout TK Pocket-Sized Thermal Monocular

FLIR Scout series has some of the best thermal imagers for outdoor. These devices are designed lightweight with features to work well outdoor.

FLIR Scout TK is the compact handheld thermal monocular that is easy to use, pocket-sized and perfect for targeting animals.

Thermal imaging technology used in this monocular includes the microbolometers to detect the heat signature difference between the objects.



Brand: FLIR

Resolution: 160 X 120

Display: 640 X 480

FOV: 20°×16°

Thermal Sensor

This FLIR handheld thermal monocular has the VOx Microbolometer (an advanced thermal sensor) of 160X120 pixels.

This uncooled thermal sensor is also one of the reasons for the lightweight feature of this monocular. Though these monoculars do not have the high-resolution sensor, these are best among the other entry-level thermal imaging monoculars with the commendable quality.

Frame Rate and Detection

The frame rate of this monocular is 9 frames per second that is decent value for entry-level monocular users.

The detection range of this compact thermal imaging monocular is about 100 yards.

LCD Display

Digital Detail Enhancement in this FLIR’s thermal monocular produces high-quality images and video recording.

It has an LCD display of resolution 640X480 pixels. Every thermal image on the display has the temperature details and contrast so you can differentiate the objects and animals.

The field of view of this device is 20X16 degrees.


Device Controls

FLIR Scout TK thermal imager/monocular has a great intuitive user-interface. There are four easy buttons to control the device.

The power button starts the device in and around 5 seconds. A short press on the image-capture button for taking photos and long-press for recording video.

Color Palettes

The device has different color palettes and allows you to choose as per your likes. So you will get the chance to modify your images and videos with your preferred colors.

The USB port in the device makes the transfer of files to your computer system or laptop easily.

Battery Life

The rechargeable Lithium-Ion battery used to power the monocular which can long up to five hours of processing time.

Read the complete review of FLIR Scout TK Thermal Monocular here.

6. FLIR Breach PTQ136 Thermal Imaging Monocular

FLIR Breach PTQ136 is a multi-purpose monocular that can be used in both day and night detection of objects. These devices are primarily designed for law enforcement but later they have been serving in home inspections and used as day/night hunting gear.



Brand: FLIR

Resolution: 320 X 256

Display: 1280 X 960

FOV: 24° × 19°

Pocket-Sized and Lightweight

FLIR TAB176WN8Q14001 Breach PTQ136 has built with 12µm Boson core which is lightweight with only 7 ounces and has a compact design. The total weight of this device is 210 grams so you can hold this imager in your hand for a long time or can keep it pocket.

flir breach ptq136 compact size
The image shows how compact FLIR Breach PTQ136 monocular is that it is just the size of his palm.

Mounting Rail

There is the mounting rail on the right side of the FLIR PTQ136 which is designed to work with different adapters. Using this, you can attach the device on any firearm or helmet and detect any objects without holding any extra weight.

Durable Body

The durable design of this PTQ136 is impact-resistant so it has a drop resistance of a meter or two. It is rated IPX7 for its waterproof design, it makes this monocular to work great in all seasons at an affordable price.


Thermal Sensor

FLIR PTQ136 has Boson VOx microbolometer that offers the long-wave IR sensitivity. The thermal sensor resolution of this device is about 320X256 pixels and the refresh rate is 60Hz, so the sharp and clear images are promised.

Built-in Zoom and Display

PTQ136 has the 1280X960 HD LCD display so you can see everything your camera detects. The built-in zoom function of this monocular adds extra benefit to the users. With this, you can focus the objects and see them in closeup.

Video Recording

The PTQ136 monocular can able to record video and take images. The internal storage of the imager can store up to 1000 images without video files. Instead, if you want to record the video, the internal storage will stores up to 2.5 hours of video.

You can store both images and videos on the device but considering the storage limit, it is better to take either images or videos from the user’s point of view.

Here is the detailed review of the FLIR PTQ136 thermal monocular.

7. Leupold LTO Tracker Thermal Monocular

Leupold LTO Tracker Thermal Monocular is a thermal imaging mini system that very much resembles a small torch that can fit in a single hand. The heat signatures of a target can be picked by this 1.5-pound monocular at a distance of about 400 meters.



Brand: Leupold

Resolution: 206 X 156

Display: 240 X 204

Frame rate: 30Hz


This precise and handy thermal viewer is very impressive to use and experience the elite and enjoy outdoor recreations. This Leupold LTO Tracker Thermal Monocular is not only an easily accessible device but it also prevails in the list of durable and waterproof monocular.


Waterproof is the most required factor which would help people to visualize the presence of counter agents even in cold weather and rainy seasons.

Build Quality

The thermal imaging screen which is usually made up of thin plastic or germanium can provide you excellent detection of heat signatures from raccoons, deers, rabbits, rats but unfortunately, people also mistake a rock like an animal too.


Device Display

Unlike other monoculars, this product doesn’t require a big screen but it is provided with an adequate screen that can allow visuals from the direct view.

Zooming Function

This product also consists of a 6X zoom which pretty much allows producing a six times larger image. moreover, it is also suitable to carry it in a pocket and the rugged outlook of this monocular provides impact-resistant protection.

Here is a video shared by a Leupold LTO Tracker user who viewed people and things around them through this thermal viewer.

Read the full review of Leupold LTO HD Thermal Imaging Tracker.

Tip:- Here we’ve compared the best monoculars from Leupold & FLIR (Leupold LTO Tracker VS FLIR Scout TK).

8. Bestguarder Digital Night Vision Monocular

Bestguarder Digital Night Vision Monocular is an occult and fantabulous monocular which has many attractive features to move your mind beyond excitation.



Brand: Bestguarder

Resolution: 2592 X 1944, 1600 X 1200,  640 X 480

Display: Vary

Objective lens: 50mm

Different Resolutions

Photographs can be easily snapped at various resolutions including 2592 x 1944, 1600 x 1200, 640 x 480 and videos of 1280 x 720 and 640 x 480 can be recorded at a rate of 30 frames per second which is not present in many other monoculars, which means the speed of the video would be in such a way to see 30 images in one second.

Rugged Design

This Best guarder Digital Night Vision Monocular has a rugged housing inside which conceals an inbuilt IR illuminator to provide extra clear and lucid night vision. The viewing range of this monocular is 350 meters which is reinforced with a 6X magnification.

Device Display

The screen can be switched to NTSC/ PAL standards which provide a good thermal imaging while exploring, fishing, nighttime navigations, hunting, and rescuing.


Storage and Weight

Moreover, this 2.2-pound monocular is associated with a tripod jack, micro SD card, inbuilt microphone which enables us to take colorful video with sound.

Connectivity Feature

Visualizing, recording and snapping a color photo coupled with the television or a computer through the video output port provides us a pleasant entertaining feature.

Have a look at a complete review of the Bestguarder WG-50 Digital NV Monocular here.

9. Armasight Multi-Purpose Spark Thermal Monocular

Armasight Multi-Purpose Spark Thermal Monocular is a sharp and distinct thermal monocular which looks pretty much similar to an ordinary video camera.



Brand: Armasight

Resolution: 60 – 70 lp/mm

Display: Unavailable

FOV: 35°

Thermal Sensor

It has a dynamic sensitivity to provide double-resolution up to 70 lp/mm (lines per millimeter) which technically means 35 white lines and 35 black lines can be drawn in one millimeter.

It is also enriched with the optional camcorder with the appropriate cords which allows you to enjoy camera footage and images even on a dark night.

Zooming Feature

Armasight Multi-Purpose Spark Thermal Monocular also has a 3x zoom which means visualizing 3 times larger image than a normal image using this night vision monocular, besides, this monocular is made up of CORE technology to prevent the edge distortions of the image visualized on the screen.

There are also accessories provided along with this product to mount the device on the head which makes your hand free from carrying it.

IR Illuminator

Attaching this Armasight Multi-Purpose Spark Thermal Monocular with the camera will bestow you with an amazing outdoor enjoyment which also provided with easily controlled buttons and IR illuminators.


What is an IR illuminator?

It is an illumination produced by the infrared lights which are invisible to human eyes.

Magnification Range

The magnification range of this product is around 3 x ranges and it is operative only at a range of temperatures from -40° C to 50 ° C which is powered either by 3V CR 123A lithium-ion battery or a rechargeable battery of the same kind.

Armasight Multi-Purpose Spark Thermal Monocular should not be used inside water bodies or in the rainy season because it is just a water-resistant device not waterproof and it weighs about 0.8 lbs and has a warranty of 2 years.

For the user’s convenience we’d like to inform you that, this particular product is unavailable right now if it comes back to the market, intimations will be given shortly for the customers by us.

10. FLIR Scout III-240 Thermal Imaging Monocular

As we know FLIR stands for Forward-Looking Infrared Cameras. FLIR is a dominant organization that provides innovative solutions in the field of thermal imaging by contributing various products, favoring units like electrical, mechanical, measurements, marines, law, gas detection, traffic, etc.



Brand: FLIR

Resolution: 240 X 180

Display: 640 X 480

Frame rate: 30Hz

High Resolution

FLIR Scout III-240 Thermal Imaging Monocular is also one of the heavenly outcomes of the FLIR organization which provides an esoteric thermal visual with the help of a high-resolution screen that has a resolution of about 640 x 480 pixels.

Detection Range

Also, it allows the performance of the thermal imaging process by analyzing even very small temperature points at a distance of 350 m for detecting a man and 945 m for detecting small objects which are very close to 1 km. 

Frame Rate

The frame rate for this world-class product can be as high as 30 Hz or 60Hz which can allow change of the screen frames in several milliseconds and thus provides a high standard video.

This FLIR Scout III-240 Thermal Imaging monocular can provide you best support during hunting, land surveying, searching, camping and any other recreational purposes moreover, this monocular collects the heat signatures from various animals and provides you a highly defined image; besides it is reinforced with multiple screen color selecting options, by which you can enhance your screen with several illuminant colors like orange, yellow, white and blue.


Compact and Lightweight

This compact thermal imaging monocular is very small such that it can fit inside your pant pocket and so it is very much a portable device; moreover, the weight of this product is around 0.75 pounds which makes you feel it like a feather.

Adjustable Features

This powerful monocular can be easily be used without any prior training and also it has fine zooming facilities coupled with the brightness adjustment option and this clash resistant monocular with dazzling features is powered by one lithium-ion battery.

Check the complete review of FLIR Scout III 240 Thermal viewer here.

For the user’s convenience, we’d like to inform you that, this particular product is unavailable right now if it comes back to the market, intimations will be given shortly for the customers by us.

11. Pulsar Lite Quantum Thermal Monocular

Pulsar Lite Quantum Thermal Monocular is one of the stylish and muscular monoculars which provides a sound grip to the user and also provides a crystal clear screen with a high definite resolution of 384 x 288 pixels, moreover the refresh rate is satisfactory to 50 Hz.



Brand: Pulsar

Resolution: 384 X 288

Display: 640 X 480

Frame rate: 50 Hz

Different Modes

This innovative pulsar quantum monocular can be calibrated in automatic mode, the semi-automatic mode and also in manual mode which is also supported with the stadia metric rangefinder in which distances are measured with the telescopic instrument to find the exact distance of your counter agent from the monocular.

High Resolution

Pulsar Lite Quantum Thermal Monocular proves to be more lucid in providing smooth and crisp thermal images on a high-resolution screen with the 640 x 480 pixels through the active-matrix organic light-emitting diode technology which is a thin film technology containing electroluminescent organic compounds which require no backlight like an ordinary LED screen.


The clarity is great not only because of the pixel rating but also due to the pixel pitch ratio which is as small as 17 micrometers (0.017 millimeter), which is exactly the distance from the center of one pixel to the other.


Added Features

This monocular can visualize the thermal images even beyond 275 yards which also has seven different color viewing modes apart from the monochrome mode and also this robust monocular switches off automatically when not in use thus saving the power.

Not only that, this product works on both hot white and hot black mode and weighs around 1.9 pounds with the dimensions of 6 x 10.5 x 4.5 inches.

The hand straps associated with this monocular prevents the accidental damage of the device and this Pulsar Lite Quantum Thermal Monocular is powered by 4 AA batteries which are also equipped with the adaptable power supply.

Did you know?

Did you know? Thermal imaging is being used to minimize the spread of Coronavirus (COVID-19) by detecting body temperature that is using their heat signature.

Yes, Infrared thermography can able to detect the elevated body temperature that may be a cause of fever.

thermal scanning for covid 19
In Delhi Airport, they use thermal scanners to check the passengers for COVID-19.

In that case, using IR radiation as a diagnostic tool to inspect people for fever may minimize viral diseases such as COVID-19 (coronavirus), SARS, and other infections from spreading.

Because fever or raising body temperature is a definite symptom of severe flu and bacterial infections.

Death and people got infected to COVID-19 massively increases worldwide, so public health ministries are in the search to find a better way that is reliable, easy, fast, and contactless to contain the COVID infections.

Where they found thermal screening, it is the best option as of now when appropriately used.

Thermal detection is now used around the world in all the public places and transport areas to detect the temperature change in civic groups.

If you want to know more about how Thermography uses in Elevated Body Temperature Screening, check this PDF.

Important Things to Know Before Choosing the Thermal Imaging Monocular or Thermal Viewer

What is a Heat Signature?

Every object in the world emits radiations with various wavelengths but these radiations would differ from each other.

The humans and certain animals emit radiation in the range of 0.75 to 1000 microns which is very much similar to the wavelengths of the infrared radiations aka infrared signature (Check Wiki for a complete history of IR radiation).

This heat radiation from each object is called the heat signature.

Infrared radiation cannot be seen by the naked eye because of the ocular limitations of the human eye.

The IR radiations from various objects are captured by a sensitive thermal imaging sensor that is placed inside the monocular and the images produced by these monoculars usually are grayscale in nature.

The object which emits a good amount of heat appears to be white on the screen while the cold objects appear to be black.

Difference between Thermal and Night Vision Monocular

Thermal imaging and Night Vision are two technologies used to attain the best viewing in the darkness and any unclear weather conditions.

thermal vs night vision monocular
Thermal Imaging Monocular VS Night Vision Monocular

Thermal Imaging Monoculars

Thermal imaging technology relies on the heat signature that is nothing but the emitted Infrared (thermal) energy from humans, animals and anything in this world.

And the emitted energy rate differs with every object. A thermal sensor in the device detects this heat difference in a focus area.

After processing the temperature details, it generates a heat image or heat map differentiating the temperatures using multiple colors.

Thermal imaging is an easy to use technology as they are detecting the heat energy that is typically generated by the animals and humans.

Night Vision Monocular

On the other hand, Night Vision Devices (NVDs) work based on amplifying the available light and ambient light to provide the night vision.

These are often called Star/Moon devices as they use the light from star and moon to provide better viewing at nights.

Night vision devices failed to work when it is cloudy or there is no light. In these cases, the thermal device is safe and useful to have.

Types of Thermal Monoculars

Though there are many types of Thermal imaging monocular available, these are broadly categorized into two types based on the way how they are being used.

» Handheld Monocular

» Head Mount Monocular

Thermal Handheld Monocular

Thermal Handheld Monocular is the most commonly used monoculars and popular among the hunters and wildlife observers.

Basically, these thermal devices are compact and effective that you can carry around your work field.


Most of the handheld monoculars are lightweight to reduce the burden of the user.

When compared to other types, these handheld devices cost-effective and has a long work life.

When we talk about the downside of Handheld monocular, the major problem is that using this handheld monocular for an extended time will be trouble.

Particularly, if you are detecting an entire home or a person inside any building or in any continuous usage of monocular, you’ll get tired of holding the monocular for all the day.

You can keep the device in your pocket or hang like a chain on your neck but the problem arises when you are in physical activity like running.

In that case, you have to be careful about your device so chances are there you will miss your focus on the game.

Thermal Head Mount Monocular

Another major type of thermal imaging monocular is head-mounted devices. From the name you know, these monoculars are used as mounting on the helmet or headgears.

You can easily adjust this device to the front level or take out from eye level.


Anyhow, you don’t have to hold this device in the entire task as it is a handless operation. This is an important benefit of head-mounted devices.

As these devices free up your hands, you can use your hands for other activities like climbing, using a rifle or weapon, and any physical activities.

The right attachment of helmet with mounted monocular offers better stability so you’ll get a clear thermal image.

With this head-mounting device, you don’t have to think about the storage also. Unlike handheld monoculars, you can use head-mounted devices for a long period of field works and observations.

You can simply stand or sit in a place and continuously monitor the target areas or surfaces and it also allows multi-tasking.

The main drawback of this head-mounting device is its price range. These devices cost high compared to the handheld.

You have to spend on quality headgear to use this head-mounting monocular.

Difference between Monocular and Spotting Scope

Any outdoor enthusiast should have a monocular and any hunter would have a scope that can be mounted on their weapon.

monocular vs scope
Monocular Versus Spotting Scope

Both devices are essential gear for outdoor activities like hunting, climbing, camping, etc. Most of the time buyers confused between monocular and scope as they look the same but they have their own unique features and working procedure.

Let look into the difference between monocular and scope to see which is best in the field.

What Is a Monocular?

The monocular is probably similar to binocular. It is a portable and compact tool that can be used as a magnifying glass by the hunters or campers.

We can say it as a half barrel of binocular. So the user has to see through one eye using this device and thus it has named monocular where the meaning of “mono” is ‘One’ in Greek and “Oculus” is ‘Eye’ in Latin.

Thermal monoculars are such indeed optic devices to have. But these are also available with advanced features like built-in compass, rangefinder, and zoom power.

What Is a Spotting Scope?

We already said monocular is similar to binocular, likewise, spotting scope is much similar to the telescope. These spotting scopes are the largest optic a hunter will find.

Spotting scopes looked as the high-powered optics with large apertures. The features of this device allow seeing the small animals like birds, deer, hogs, etc with details away from 100 yards even while moving.

Let look into the advantages and disadvantages of Thermal monocular and Spotting Scope.

advantages of spotting scope and monocular
disadvantages of spotting scope and monocular

Monocular Vs Spotting Scope: Which is better?

The monocular and spotting scopes are completely different devices. Monoculars are lightweight and portable hunting or viewing device while scopes are heavyweight but provide clarity thermal images.

In Hunting

With the highly portable structure, monoculars work best for hunting. But hiding from your prey is the major thing that you have to ensure while hunting in dark.

The monoculars are basically lower powered than the spotting scopes so these are not the best option here.

Spotting scopes offer the high detection range of hundred yards and more, so you can be safe and you can closely monitor your prey.

If you are not worried about the weight and tripod setting, a small size low-powered spotting scope can be the perfect choice for hunting. Otherwise, a compact and easy-to-carry monoculars are recommended.


Thermal Monocular

Spotting Scope

In Birding

Birding or Birdwatching is the form of wild observation in which the rare birds are observed, captured or recorded. It can be done by the naked eye or using any visualization tools like binocular, monocular, scopes, and cameras.

A spotting scope will provide clear images of birds’ feathered bodies and activities. But setting up the tripod and change it for every new spot will be hard.

In such cases, monoculars win the race. You can hold the device in your hands or carry it as a chain or mounted in headgear. So you can watch or catch the actions of the birds instantly. This is more practical gear than the spotting scopes.


Thermal Monocular

Spotting Scope

In Astronomy

You can see some соnѕtеllаtіоnѕ using a monocular but there is no big difference than seeing the same with the naked eye. Monoculars are just low-powered to see far.

The scopes provide the image right side and correct to the right from left, unlike the telescope with which scopes often compared.

The maximum magnification range of most of the monoculars is just 10X where the minimum magnification range of best thermal scopes starts with 20X and it can provide the zoom as close as to 100X.


Thermal Monocular

Spotting Scope

Thermal Monoculars – Buying Guide

Buying a thermal monocular is an essential thing, but what are the factors that a quality thermal monocular should dominate?

Have a glance at this guide which would be so helpful to you in buying a brand new monocular without being deceived by the trader.


The durability of any device is the first and foremost factor that any new gadget should possess especially, a thermal monocular.

It can be subjected to stress, pressure, climatic change and much other trouble which should overcome by the monocular.

Monoculars with poor durability will help in cost you but will not serve your cause.

Magnifying factor

Magnifying factors as per the laws of physics can be determined by image distance/object distance. Monoculars should be able to provide proper imaging about the opponent even though the opponent is at a distance of several hundreds of yards.

Usually, magnification is specified with two numerals like 10 x 18 where the first digit (10) means that it magnifies the image 10 times larger than normal and the second digit is about the diameter of the lens in millimeters (in our case it is 18 mm lens).

Proper zooming options in a monocular will let you know about the amount of magnification available in a particular thermal monocular.

Color Modes

There are different color modes are available in all the thermal and night vision devices. Consider the modes and make sure it fits your need.

Here is the video of Leupold thermal monocular which has tested for its different modes and zooming.


Invulnerability is another crucial factor that should be noticed when purchasing a new monocular because monocular is always used in intrepid jobs which might subject the monocular to various challenging tasks.

So it is always better to suggest a monocular in such a way where it is dressed with proper fireproof and waterproof materials.


The resolution simply means the clarity of an image. Clarity is based on the number of pixels in that image.

Pixels are a small square which collectively builds a picture. Let’s explain this with an organic drawing. Fetch a hand full of yeast and draw your initial with it.

Repeat the same with some white mustard. Of course, the second drew with the mustard will be more evident and vivid to see comparing the initial drew with yeast and why does this happen?

Remember, the number of mustards will be definitely more compared to the number of yeasts and this little experiment would provide good knowledge about the resolution of a digital image.

Usually, the resolution is specified with two numbers; like 2000 x 1000 which means there are 2000000 pixels in the image. (i.e.) 2 Megapixels. So it is necessary to check the pixels of the image in your thermal monocular while purchasing it.


Whatever may be the features in a monocular, without the proper power source it is totally useless.

In dire straits, if the power supplied to the monocular is not sufficient, it may go off and imagine your lone situation within the limits of your opponent who might be a man, wolves, hounds, etc with nothing in your hands to assist you and you would be at your wit’s end at night times. Picking up the product should be carefully done such that the device is not power-hungry.

Handy and recordable

Some of the monoculars may be supported with tripods that are tightened with screws. In one perspective it seems to be safe, but on the other hand, when you have to swiftly do a job you would not be able to beat the clock with a big and heavy tripod before your counter agent gets away and so suggesting easily detachable monocular can help you in various perspectives.

All the features which can help an individual to buy new monocular have been perfectly explained in the above-mentioned guide.

I hope this guide might help you to fetch one from numerous sellers who post attractive advertisements on your wall.

Make sure you go through all these factors while investing heavily.

Advanced Features

Some of the additional and smart features offered by the thermal imaging monoculars are as follows.

Thermal Monocular with Rangefinder

Nowadays, almost all thermal monoculars and thermal scopes from popular brands have a built-in rangefinder. This rangefinder makes the hunter’s life easy. These devices avoid carrying additional equipment like a handheld rangefinder to find the range of the target.

This built-in range finder in monoculars finds the distance between your device and prey. The only job is to adjust the device and click thermal images. The smart range finder starts the range calculation automatically. So you will get the perfect shot every time.

Thermal Monocular with Wi-fi

Thermal monocular with wi-fi features allow their users to connect to smartphones or tablets to view the images and video concurrently.

So you will know what you have captured or recorded till then. You can see your game adventures and share the files from your gallery with your friends in real-time.

Some of the thermal monoculars allow live Wi-Fi video streaming on YouTube.

Thermal Monocular with Built-in Compass

The built-in compass in the device provides the angle observation relative to the direction. The reading of the compass is from 0 to 360 degrees. The meaning of readings is,

» 360°: North Direction

» 270°: West Direction

» 180°: South Direction

» 90°: East Direction

If the reading is 100°, it means 10 degrees east to south.

Thermal Monocular with Smooth Zoom

Apart from Fixed zoom, recent thermal monoculars have equipped with Smooth Zoom which provides you sensitive ultra-slow zooming.

You can stary anywhere and zoom on the screen to get a near view of everything in front of you. So you can monitor the movement of the animal or target closely which helps you take a perfect shot. All of these happen with just a button press.

Applications of Thermal Monocular

Thermal imaging monoculars are mostly used in military, law enforcement, hunting, and wildlife observations.

Thermal Monocular for Hunting

In hunting, thermal monoculars offer a clear view of the target from long distances.

Now, most of the monoculars have designed with a range finder and a built-in compass.

The rangefinder in this device provides the exact difference between the user and the target.

It will help you to stay away from attacking animals and hunt safely. Thermal monoculars are widely used for hunting deer, hog, and coyote.

Above video demonstrating how FLIR Scout TK Pocket-Sized Thermal Monocular shows the thermal imaging while deer hunting.

Thermal Monocular for Military

Thermal monocular used for the military have rugged and strong construction as they have to face more tactical and tough situations, so the devices have made as waterproof, weatherproof, dustproof, and with drop resistance.

There are few thermal device companies that have designed the tools specifically for military and security. 

MH Technology Group is one among those leading manufacturer who is developing Night vision optics and Thermal gears for Military.

The above video is explaining the features of M670 Military Thermal Monocular from MH.

Thermal Monocular for Law Enforcement

Thermal imaging devices for law enforcement help the cops or security officials to trap and find the criminals who are hiding in building or construction by detecting infrared thermal energy or radiation.

Security professionals and law enforcement officers should keep huge safety gear that makes them tiring.

But these thermal monoculars come as lightweight, portable and are one-hand operated which offer easy carry for long hours.

The attached video of FLIR Thermosight Pro PTS736 shows how it detects the hided thief using thermal imaging.


Thermal imaging is exactly done by a special germanium lens that collects temperature points from various heat signatures and provides the data to a circuit which converts this thermal optical signal into an electrical signal and then it is visualized on the screen. A thermal monocular is a very much needy gadget that would help to find missing people in bad weather.

Water leaks, floods, forest fires can also be found at the budding stage itself. Before buying a thermal monocular, a reference to such a guide that provides you massive information about the features pertaining to the technology and price is more essential. That way, you can get a monocular for your own use knowing various significant features.

Frequently Asked Questions

How law enforcement use this thermal technology?

Thermal imaging devices help the police officers to stay safe while searching or trapping the criminals who are hiding in the building or dark places. Thermal devices can be used to identify a recently passed car by detecting the warmth of the hood, these are also used to collect the evidence from the crime spot and help to find the suspects.

Can thermal imaging see through clothing?

Not up to the mark. For example, if a person has a gun under his/her shirt, the outer parts shown as “cooler” on the thermal camera with that police officers identify that the person may have a gun.

Can thermal imaging devices see-through walls into the building?

The answer in one word is “NO”. Thermal devices only detect the heat that radiated from the objects. The device will detect the heat coming out from the home but it can’t see what is inside the house as it first captures the thermal image of the house’s exterior.

What does Emissivity mean in Infrared Imaging?

Emissivity, also known as “E” value is always noted as a percentage which shows the value of a place or surface for emitting electromagnetic energy at a given wavelength. The percentage is ranged from 0 to 1.
0 – No Emission of IR Energy
1 – Efficient Radiating Surface
But, in the real world, the E value is always noted as less than 1 such as 0.45 or 0.95.

Is thermal imaging dangerous?

Not at all! Thermal imaging is just another technique to see in the dark. Everything that emits infrared radiation is detected and captured or recorded as thermal image/video by the thermal devices like thermal camera, thermal scope, and thermal monocular.