Glossary

f-number (ƒ/#) or Aperture/Iris Size

The ratio of a lens’s focal length to its aperture size. Lower ƒ/ numbers mean that more light or thermal energy is reaching the sensor, which increases colour accuracy in visible images and increases definition and accuracy in thermal images.

Anti-Reflection (AR) Optical Coating

A type of coating applied to lens elements to maximize the performance and accuracy of the lens by reducing internal reflections.

Aperture/Iris

An adjustable diaphragm that controls the amount of light coming through the lens.

Aspect Ratio

The ratio of width to height in a video display or image sensor.

Auto-Iris Lens

An automatic adjustment to regulate and optimize the amount of light or infrared energy a camera receives.

Cooled Thermal

Cooled thermal imaging uses an integrated cryogenic cooler, which chills the thermal image core to temperatures as low as -196°C (-321°F) to increase the sensitivity and accuracy of the thermal image.

Detection Rating (DRI)

Based on the DRI standards, detection means that you will be able to see the target, however it will be little more than a speck. There is a 50% chance that the target will be visible on at least two pixels, and there is a good chance that it is something of suspicion.

Digital Camera & Thermal Imaging Sensor Sizes Explained

Let’s face it, digital camera sensors are measured in ridiculous ways. If you’re trying to make sense of what dimension a 1/2.8" sensor size is referring to, or if you’re wondering how thermal imaging sensor measurements are different, you’ve come to the right place.

DORI (Detection, Observation, Recognition, Identification)

Detection, Observation, Recognition, and Identification (DORI) are a set of standards used to compare the performance of visible light surveillance cameras.

DRI (Detection, Recognition & Identification)

A universally accepted set of standards providing a means of measuring the effective distance of thermal infrared cameras.

DRI: Thermal Distance Ratings Explained

Detection, Recognition, and Identification (DRI) are a universally accepted set of standards used to compare the performance of thermal infrared cameras.

Electromagnetic Radiation

Waves of electromagnetic energy that travel through space. Examples include radio waves, WiFi, microwaves, radiant heat, visible light, ultraviolet, x‑rays and gamma rays.

Electromagnetic Spectrum

The combination of all of the various frequencies of electromagnetic radiation. This includes radio waves, WiFi, microwaves, radiant heat, visible light, ultraviolet, x‑rays and gamma rays.

FLIR (Forward Looking Infrared)

Refers to the technology used to create an infrared image of a scene without having to “scan” the scene with a moving sensor. It is also the name of a thermal imaging camera manufacturer (FLIR Systems).

Gyro Stabilization for PTZ Cameras

Mechanical stabilization of a PTZ camera system by using the pan/tilt head to counteract movements detected by a gyroscope.

Identification Rating (DRI)

Based on the DRI standards, identification of an object means that you are able to differentiate within a class of objects. For example, this person looks like a tall woman wearing a dress, that person looks like a soldier.

ITAR (International Traffic in Arms Regulations)

ITAR is a United States regulation to control the export of defense and military related technologies. Some of our products fall under these regulations and may only be sold or exported if authorization from the Department of State is received.

LWIR (Long-Wave Infrared)

A subset of the infrared band of the electromagnetic spectrum, covering the wavelengths ranging from 8µm to 14µm (8,000 to 14,000nm). This is the radiant heat that uncooled thermal imaging cameras see.

Micron (µm)

Microns, also known as micrometers (represented as µm) are a length of measurement equal to one millionth of a meter. (1,000µm is equal to 1mm.)

MWIR (Mid-Wave Infrared)

A subset of the infrared band of the electromagnetic spectrum, covering the wavelengths ranging from 3µm to 5µm (3000nm to 5000nm). This is the radiant heat that cooled thermal imaging cameras see.

NIR (Near Infrared)

A subset of the infrared band of the electromagnetic spectrum, covering the wavelengths ranging from 0.7µm to 1.4µm (700 to 1400nm).

ONVIF

ONVIF is a standard for IP video surveillance devices. While it usually works well for basic video integrations, ONVIF is not ideal for handling PTZ commands of EO/IR systems and does not allow for many advanced commands such as switching thermal palettes, enabling gyro stabilization, enabling NIR/Fog Filters, etc.