Thermal optics are used to detect radiation. Which means higher the temperature the more radiation it shows. The thermal optics detect heat as the target temperature is higher then it’s surrounding the thermal optics gives you an image (Thermal scopes take heat energy and converts it into colors that humans can easily see).
Thermal optics do not require visible light as they use radiation to show the image of your target.
To understand Infrared Scopes you need to know about the electromagnetic spectrum. It consists of everything from radio waves, visible light, and further on. Out of these wavelengths only small amount of waves human eyes can see.
It is known as the visible light spectrum beyond this visible spectrum lies the infrared spectrum. The Infrared spectrum was first discovered by astronomer Sir William Herschel, in 1800.
With the help of thermal scope, you can also see hidden small animals or target in a fog. The downside is that as you are viewing in thermal scope you will not have a detailed image of the object.
The infrared light is collected by the lens in the scope. Then it is scanned by sensors that send the signal to a microprocessor. The microprocessor function is to convert different heat into different colors that are visible to the human eye.
Basically, the thermal scope is a camera which takes images of infrared light which converts it into visible light.
They are divided into two main categories cooled, and uncooled.
Cooled thermal imager:
A cooled thermal imager consists of a system of liquid nitrogen for its cooling. Which makes them fragile and massive and are not good to be placed on the top of a rifle scope.
It is more sensitive to heat than an uncooled one. They can measure temperature changes up to .02f. Which allows its user to see the image from extremely far away.
Because of this, they are usually used in satellites and military planes for observation.
Un-cooled thermal imager:
The uncooled thermal scopes are those which operates at room temperature. This scope allows a person to view an image of the target within a temperature range of -4f to 4,000f which is good for hunting.
- Can see in any light condition.
- Easily see through smoke, dust, fog.
- Works during the day
- Tracks residual heat such as recent footprints, droppings, and blood.
- Works in Zero light Condition
- Large and Heavy.
- Requires regular maintenance.
- Gives a less clear image.
As thermal scopes produce images from heat, the night vision requires a light source to provide an image.
Night vision scopes amplify visible light which enhances the existing light making it visible to the humane eye. The night vision has been around since world war 2 and there has been a lot of improvement as better technology has continued to evolve.
Night vision consists of an image intensifier tube which collects and amplify both visible and infrared light. Light enters into the lens of scope and hits photocathode. Which converts photon of light energy to the electron.
When electrons are passing through the tube then they are amplified by microchannel plate which strengthens the signal. And these electrons then collide with photo screen (the screen that is coated with phosphors) which result in green images we see in night vision.
Night vision images are natural and more detailed. The downside of night vision is that they are sensitive to bright light and can be damaged if exposed. Night vision scope cannot be used in the day but only at night.
Also here is a guide for best night vision scopes.
There are four types of night vision scope:
- Generation 1
- Generation 2
- Generation 3
- Generation 4
Gen 1 was introduced in early 1960, it is cheap. Its average range is more and less 75 yds and average resolution. Have lower battery then Gen 2 and further.
These scopes are usually more expensive than gen 1 and have a lot of improvements then gen 1. Its average range is 200 yds. Its images are much brighter and Better resolution.
Longer battery life then gen 1 devices. 2nd Gen is best for those who want to use it as a hobby or predator control.
Gen 3 is more advanced than Gen 2. As they are used by the military and is way more powerful with its advanced technology and accuracy. They provide amazing image quality and low light performance.
The sight range is 300 yards. But they are quite expensive.
Gen 4 is currently the latest technology available right now. It is a better-enhanced version of all the scopes features put together in Gen 3 with more advanced features it can perform excellently both in low and high-level light condition.
- Longer battery life
- Cheaper than thermal scopes
- Provides detailed image
- Lighter and smaller
- Needs light source
- Can’t see through Fog, Smog
- Can only be used at night (Most Models)
Both Night vision and Thermal scope have advantages and disadvantages. Making it harder to choose which one to buy. But you need to consider several factors such as price range, hunting, or in which environment the scope will be used.
Which is better for Hunting (Night Vision vs Thermal Scope)?
Thermal scope detects heat or radiation and night vision scope amplifies low light. If you are hunting in a good light condition both day and night then the thermal scope will be your best choice as night vision can be damaged by bright light. If you hunt in an area where the temperature can be freezing or you like to hunt at night (requires light source e.g moonlight) then night vision is a great choice for you.
Environment (Night Vision vs Thermal Scope):
It depends upon you in which environment you will be hunting e.g will you be hunting in an area where the temperature is cold, freezing or rainy environment then night vision is a better choice because weather affects thermal imaging.
Or if you are in an area where there are lots of bushes, fog or smoke then the thermal scope is a better choice as it can detect animals hiding in the bush or in fog.
What is your budget?
It also depends upon how much budget you have because for most of us cost is a big issue. As thermal scopes are usually more expensive than night vision scope. Most people go for a night vision scope because of this.
Both night vision and thermal scope have their own weakness and strength so it is up to you what you want in a scope. The best combination is thermal monocular for spotting your target and night vision for taking shots.