How to Choose a Thermal Monocular?

Perfect thermal monocular as multifunctional tools could be a “game-changer” for variate needs. Detecting and searching with less limitation are the main reason that thermal imaging monocular are born while humans will have disadvantages in observing with the traditional instruments. But for the actual question that will be listed out: how can we choose the perfect thermal monocular? Before come with that, let’s start with a simple introduction of the working principle on thermal?


Everything with a temperature over -273.15℃ emits infrared thermal radiation. The higher the temperature, the stronger the radiation is. The thermal sensors inside of the device detect the radiation and transform it into electric signals. Through the complex digital processing, these signals will be converted into thermal imaging and displayed on the high-resolution OLED or LCOS screen, that’s how the thermal works commonly.


Back to the question, when you decided to upgrade your setup to thermal monocular or just newcomer interested in thermal monocular, the first factor you should think about is your budget for it. High quality thermal monocular is a high-value product because of the production cost. With a certain budget, the next thing we should pay attention to is the main specifications that affect the performance.

How to Choose a Thermal Monocular

Major Specifications for Choice

Thermal Sensor

It should be known that thermal sensor resolution directly affects the clarity of the thermal image. Under the same pixel pitch, the higher the sensor resolution, the clearer the thermal imaging quality is. Nowadays the mainstream of sensors on the market are 12μm and 17μm, under the same condition, the units with 17μm sensors usually create clearer and more crisp thermal imaging. However, the shorter detection range is the weakness of 17μm compared to 12μm. And with trends, 12μm thermal sensor holds gradually the dominate status.


Thermal Lens

The material of the lens determines the light transmittance, which has a certain impact on thermal image quality. InfiRay thermal monoculars adopt Ge-lenses, which have higher transmittance and lower reflection to thermal radiation ranging from 8-14μm. The focal length of the lens also determines the detecting range. The larger the focal length, the farther the detecting distance is.  


Sensor NETD (Sensitivity)

NETD comes with sensor performance. In fact, it is this parameter that determines the sensitivity of the thermal monocular which means the minimum temperature difference that the product can detect. If sensor NETD≤25mK, it means that the minimum temperature difference that the detector can detect is 0.025°C. Thus, the smaller the NETD, the more sensitive the thermal monocular is. With industry-leading thermal sensor technology, InfiRay has released thermal monocular featuring sensor NETD≤25mk (@25 °C,F#=1.0), with ground-breaking features the users will experience from it.


Detection Range

With certain detection range parameters you can know exactly how far the thermal monocular can detect and search. Take E6 Plus thermal monocular, a detection range up to around 1280 meters denotes that a standard human target size 1.7m×0.5m under the humidity condition can be detected in distance of 1280 meters. More importantly, you should have the recognition between visible range and detection range. When visible range focuses more on the recognition, the detection range places high value on detecting the target.  



There are two kinds of batteries for thermal monoculars on market, integrated built-in batteries and the replaceable battery pack. It’s a side-by-side comparison. The built-in battery has gained advantages in constructive stability and durability, while the portability and continuous battery time keep with replaceable batteries. 4-5 hours using time is commonly sufficient for hunters.


Menu Options

The reason why thermal monocular can be a “game-changer” is that it is internally multifunctional as well as powerful outside. The user is capable of handling the circumstance with versatile options through which he can taste the freedom even in the complete darkness. The most commonly used functions on the thermal monocular are PIP (picture in picture), color palettes, video and photo taking.


For new thermal goers, InfiRay has plenty of entry-level thermals, such as E3n, E6n, which can provide technical superiority and ultimate experiences. For an example of E3n, the 384×288 17μm thermal sensor and NETD≤40mK ensure crisp image quality. The internal diverse options such as 5 color palettes, PIP function, video recording, and 4 simultaneous connections through the integrated Wi-Fi module provide users with excellent thermal experiences. More importantly, 15h battery life supplies sufficient operating time to carry out activities with needs.

Choose a Thermal Monocular

For those who have years’ using experience on thermal like avid hunters with enough budgets and wishes to upgrade the outfit in your bag, just turn around and see the EYE II series. They are upgraded with 12μm thermal sensors which have greatly improved detecting range and functions. E6 Pro V2 is undoubtedly the most cost-effective thermal monocular from this series. It is designed and prepared ready for clear thermal imaging with 12μm 640×512 thermal sensor of NETD≤40mK and coupled with 1280 HD display and 50mm larger objective lens. Another outstanding feature is that the detection range up to 2597 meters ensures the users hold a comprehensive view of the targets.


In conclusion, a good thermal monocular will catch up the user’s eye when they start from the first bite. The users for whom imaging quality is the centerpiece of the decision making, s the parameters like thermal lens and its focal length, NETD and high resolution display are their main factors to consider. But for users who prefer to having functional operations and using experiences, the internal menu options like built-in memory, color palettes, Wi-FI and battery are just important as the parameters that determine the imaging clarity. So after the introduction, if you want to know more about InfiRay thermal monocular, please contact us through the following information:


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Sales Hotline: +86-400-998-3088