When purchasing night vision keep in mind that good quality night vision comes at a price and it is crucial to clearly understand what you are buying before making a purchasing decision.  Often the price is a defining factor and it is a natural desire to buy the highest performance and quality for the least amount of money. We all understand that by definition, any good quality product cannot be cheap and even a small reduction in price can indicate a significant shortfall in reliability, build quality and performance.

So what makes a great night vision device?

There are four key components that are directly responsible to purchasing a great night vision device:

IMAGE QUALITY 

The most tangible is image quality and the better the image quality the more expensive the device. Image quality is directly related to the image intensifier tube (IIT) and the concepts listed directly determine the image resolution, so the higher the numbers, the better the quality of the image through the Night Vision device;

Resolution (lp/mm)

The resolution of an Image Intensifier tube is denoted by lines pair per millimeter, and is essentially the image resolution of the picture seen through the tube. The higher the number lp/mm the higher the image quality.

Signal to Noise Ratio (SNR)

The SNR is a concept that measures the performance of an image intensifier tube in low light conditions. Typically, a good performing tube has a value of SNR starting at 20 and above. This means that the signal received by the tube is 20 times higher than the background noise.

Figure of Merit (FOM)

FOM is the overall performance of the image intensifier tube, defined by multiplying the lp/mm with the SNR. Each tube is slightly different even within the same production batch, which is why manufacturers give ranges of FOM rather than some exact values. When supplying a night vision device, a manufacturer has to provide a customer with a spec sheet for the image intensifier tube that states the tube’s characteristics and its compliance with advertised specs.

BUILD QUALITY

Many manufacturers use plastics to make the night vision housing to cut costs. This negatively impacts shock & scratch resistance as well as the overall feel of the device. Point Trading night vision housing is made from hard anodized aircraft grade aluminium without any plastic parts to ensure maximum protection of the image intensifier tubes and provide maximum durability and shock resistance. Quality optics in combination with high grade image intensifier tubes, glass lenses and electronics deliver outstanding performance.

FEATURES

Features can be for safety and convenience. Point Trading night vision devices feature in field of view (FOV) low battery indicator, inbuilt battery with ability to take either AA or CR123A , civil aviation approval, Patented Integrated Logistics Solution (ILS) for easy fleet management including log book and service records, motion activated flip up on off switching to maximize battery life, Adjustable break away helmet mount, universal mounting system for interchangeable mounting options, 24 months warranty, 20m submersible, built in IR torch with IR indicator in field of view, extended adjustments for tilt, vertical and horizontal movement, extended fold back position over helmet reducing neck stain and cockpit bump.

ITAR-FREE 

Having no ITAR components provides ease of exportation (fully exportable) and no limits or restrictions on performance characteristics such as Figure of Merit.

The specification requirements of the Night Vision device greatly determine the price. There are several factors influencing the price.

Configuration

Is the required device a monocular or binocular.

Colour

The colour of the phosphor has a small impact on the price. The Black and White tubes cost a fraction more than the Green tubes.

Tube Specification

The 4G & Gen 3 image intensifier tubes are the highest grade of tubes that Point Trading offer in their night vision devices. Lower grade tubes are also available dependent on the application and use of the night vision devices by the operator. The tubes influence the FOM, Resolution (lp/mm) and SNR to determine the clarity of the image visible through the device.

Housing Material

Point Trading uses a hard anodized aircraft aluminium outer housing to protect tubes from damage. Our range of devices are the lightest ruggedized NVG’s on the market, shock proof and water resistant. This also impacts the price of the devices, but ensures our products last longer and are more durable than our competition.

Night Vision is different to Thermal, and DRI does not apply to night vision technologies. Night Level is the concept that determines how far an operator can see with Night Vision. A cloudless moonlit night with stars is considered Night Level 1, where there is plenty of ambient light; Night Level 6 is a dark night with very little to no ambient light, example under forest cover or in a cave. In a Night Level 6 situation, an operator would need an IR torch to illuminate the area. Night Vision technology put simply, is used to enhance vision at night time, so what one sees during the day, the same can be seen at night.

Night levels and lux range they represent:

Night Level 1 – 40 to 1000 mLux – Full Moon

Night level 2 – 10 to 40 mLux – Half Moon

Night Level 3 – 2 to 10 mLux – Some Moon

Night Level 4 – 700 uLux to 2 mLux – Starlight

Night level 5 – 70 to 700 uLux – Overcast Starlight

Night Level 6 – Below 70 uLux – Under Canopy or indoors

Point Trading prides itself on its R&D and servicing department. With most brands of goggles, night vision equipment needs to be serviced every 180 days however Point Trading Night Vision only requires annual servicing. Due to ITAR restrictions, competitors night vision who use USA components can be in transit for 3 to 6 months, and sometimes longer. Point Trading Night Vision is ITAR Free with a turnaround time for service as short as 72 hours with prior notice.

The global market offers a wide variety of thermal imaging devices. Despite the fact that most information is available on the internet the problems remains; how do you select the device that would perfectly fit your requirements and budget? What performance parameters are really important? How do you navigate the maze of specs, configurations and special terms?

Asking the right questions will lead you to making the right purchasing decisions.

A thermal imaging device works much the same way a digital camera does. The only difference is that a digital camera senses visible radiation, while thermal imaging devices work in long wave-infrared range so react to temperature related IR radiation and not light.

Image quality is one of the most tangible parameters to purchasing a thermal imaging device. The better the image quality the more expensive the device. There are three main parameters that are directly responsible for image quality; FPA Resolution, Thermal sensitivity, Refresh Rate. For best results choose a device with high FPA Resolution, high Thermal sensitivity and a high Refresh rate.

RESOLUTION (FPA)

FPA Resolution (focal plane array) is a key performance parameter that directly effects how clear you will be able to see with your thermal device and has a profound influence on the price. The higher the resolution the higher the image quality and the higher the price.

THERMAL SENSITIVITY

Thermal sensitivity is the description of how well a thermal device distinguishes temperature differences and is expressed in mK. A lower the numerical value in mK indicates a higher sensitivity because the device can discern even smaller differences in temperature.

REFRESH RATE

Refresh rate is expressed in Hz (Hertz) and indicates how many times the video image refreshes in one second. The same as applies to your computer screen or TV. Thermal image devices with  refresh rates of 25Hz and above deliver superior responsiveness and fluid live video image with no lags. For example a 50Hz thermal imaging device provides 5.5 times smoother video image than a 9Hz.

Detection, Recognition and Identification or DRI, is a universal standard that provides the means of measuring distances at which a thermal sensor can produce an image of a specific target.

DETECTION

Detection refers to the distance at which a target initially appears in the image. This “target” is something out of the ordinary that is warmer or cooler than the ambient surroundings.

RECOGNITION

Recognition in this situation does not mean that you can recognize an individual. Recognition refers to the distance at which you can determine an object’s class whether it is a human or a car, a truck or a tank, etc.

IDENTIFICATION

Identification refers to the distance at which you can differentiate between objects within a class. For example, identifying the type of vehicle (truck, SUV, or car) or whether the human is a soldier or civilian.