Latest IR cameras boast of superior sensitivity and small sizes

These cameras are available in a wide range of resolutions, pixel pitches and packaging options. Some of the recent infrared innovations deliver more cost-effective thermal analysis solutions than ever before 

By Richa Chakravarty

Thursday, August 14, 2014: An IR camera creates images from infrared radiation. Also known as a thermographic or night vision camera, it uses wavelengths longer than that of visible light to create images even in complete darkness. An IR camera works by detecting the amount of radiation being emitted from an object based on its temperature. It detects infrared energy (heat) and converts it into an electronic signal, which is then processed to produce a thermal image on a video monitor. The hotter the object, the more radiation it emits and the more intense the image colour will be. During the day or when light is available, these cameras produce a colour image. When the amount of light drops to a preset threshold, the camera automatically switches to infrared mode.

What’s new in the market

The amount of light is very important for IR cameras. The quality, sharpness and the range at which a picture can be seen by the camera depends on the amount of IR light available and, of course, the camera’s lens, type of video sensor and support circuits. The latest IR cameras boast of superior sensitivity, a small size and are available in a wide range of resolutions, pixel pitches and packaging options.

Some of the recent infrared innovations, particularly detector technology, the incorporation of built-in visual imaging, automatic functionality, and infrared software development, deliver more cost-effective thermal analysis solutions than ever before.

IR cameras with colour images: The latest technology in IR cameras uses three charge-coupled-device (CCD) image sensors and an image processing technique. This new technology makes it possible to record clear, high-frame-rate colour videos even in darkness. While the camera functions as an ordinary HD colour camera under visible light, in darkness, infrared light is projected from an infrared projector fixed to the top of the camera to record infrared images. The camera’s internal image-processing system converts them into colour images. To enable much finer and faster image processing, a 3CCD recording method has been developed. Also, the frame rate of earlier infrared colour night vision image-recording technology has improved from 10 frames per second to 30 frames per second.

Hikvision’s ultra low-light DS-2CD6026FHWD DarkFighter network camera is one such device, which delivers full colour images during the day and night, more effectively than conventional monochrome IP cameras and low-light cameras. It uses 3D digital noise reduction (DNR) technology, which can stream video in full 1080p HD at 60 fps. This results in latency-free clear images, during the day and night. A defog feature is also incorporated to noticeably improve image clarity in poor weather conditions, such as rain or fog. “This new camera features a region of interest (ROI) codec, which enables the resolution of specific parts of an image to be increased while decreasing the non-ROI image quality to minimise bandwidth and storage requirements,” says Ashish P Dhakan, managing director and CEO, Prama Hikvision India Pvt Ltd.

Opines Kaushal Kadakia, product manager, Video Surveillance Solutions, Matrix Comsec, “Smart IR cameras help the user to easily cover larger distances and conduct closer inspection without compromising on picture quality. The smart IR technology allows users to adjust the intensity of the camera’s IR LEDs. This compensates for the distance of an object from the camera so that the infrared does not overexpose the object. The problems like whiting out of images due to the closeness of the object to the camera can be solved with the smart IR technology. Also, the high speed IR dome cameras provide very high detailing as they have pan, tilt and optical zoom options because of which a higher level of security can be provided.”

Matrix will be launching IR dome and IR bullet cameras in July 2014. These include both analogue as well as IP cameras. The IR range covered by these cameras varies from 20-80m with the same clarity. These cameras will come with both the varifocal as well as fixed lenses.

IR cameras with multiple LEDs: Today, common IR LED cameras are being replaced by array LED IR cameras. According to Vinod Tyagi, product manager, Fortune Marketing Pvt Ltd, “Array LED IR cameras give better results with minimum power consumption compared to common IR LEDs, which generate much more heat, consume more power and are very big compared to array LED IR cameras.”

Secureye 720p series offered by Fortune Marketing Pvt Ltd has third generation array LED IR night vision technology that ensures superb clarity, sharpness and brightness even in pitch darkness. It offers good quality and comes with 1000TVL horizontal resolution, which is the highest in analogue cameras.

The night vision cameras of Enterprise Software Solutions Lab Pvt Ltd (eSSL) feature multiple IR LEDs that allow the user to see clear black and white night vision images in complete darkness (ranges vary by camera mode) with lenses of different capacities.

Axis’ Q1765-LE network camera has built-in IR illumination, provided by four auto adjusting LEDs that are highly power efficient. “AXIS Q1765-LE can cover great distances, providing both wide overviews as well as detailed images for identification purposes. In addition, Axis’ unique corridor format allows effective monitoring with higher resolutions in vertical scenes such as long streets or along vast perimeters,” adds Sudhindra Holla, country manager, Axis Communications India. It is a slim, bullet-style outdoor-ready network camera with 18x optical zoom and auto-focus. It delivers HDTV 1080p video in multiple, individually configurable H.264 and motion JPEG video streams.

High image sensors and wide lenses: With the advances in technology, the cameras are being upgraded from video graphic array (VGA) class (640×480 pixels) to full high definition (HD) class (1920×1080 pixels) to enable HD colour image recording. Along with this, the new cameras also provide a choice of wide angle and telephoto vari-focal MP lenses, which allow them to adjust the position of the image sensor to obtain an optimal focus. The user can not only detect motion through these cameras but can also mask the area if necessary.

Bosch recently launched its 9000 series of cameras, which are IP65 rated. The flexidome 9000 MP cameras are vandal-resistant, corner-mounted and feature a no-grip, anchor-free design. The high resolution 1440×1080p images and the integrated infrared illumination allow 24/7 effective professional networked surveillance in high risk, vandal-prone applications under any ambient lighting conditions, even completely dark rooms. “The ultra-wide lens enables the camera to view a small room entirely, including the floor beneath the camera. The innovative design allows a perfectly flush fit with no anchor points for maximum safety,” adds Sudhir Tiku, head, South Asia, Bosch Security Systems.

IR cameras with zoom adaptive technology: With this technology, the user has the ability to change the field of view of the camera, narrowing the size of the area covered as the camera is zoomed in. As soon as the user zooms in the camera, it effectively captures the image of a smaller area farther away. When using IR light to illuminate the imaging area, cameras with zoom adaptive (multiple LEDs) IR technology dynamically focus the IR light on the area covered by the camera. As a result, the IR beam angle is focused along with the lens, to illuminate an area that is smaller but farther away. This common yet beneficial feature is found in almost all good IR cameras.

How to choose an IR camera

When buying an IR camera, buyers are advised to consult systems integrators or suppliers, as a number of IR cameras with different features such as wide dynamic range (WDR), auto iris, vari-focal lenses, being vandal-proof, on screen display (OSD), etc, are available in the market. IR cameras should be bought keeping the application in mind (indoor, outdoor, etc).

“Understanding the components and how they affect the IR camera’s performance is an important part of knowing what to look for—such as choosing the right lens, the right output resolution, the right sensor, etc. Other factors are more dependent on the intended use of the IR camera, as some types are more useful in some situations than others. A day/night camera is great for keeping an eye on visitors coming up the drive, but it may not be the best choice for monitoring staff or business premises,” suggests Sudhindra Holla.

“Choosing the angle of the LEDs is a major point to be kept in mind while buying an IR camera. Depending on the distance to be covered, users should choose LEDs with either a larger or smaller angle. Also, buyers should be careful about the temperature parameters of LEDs, which determine the life and performance of LEDs,” advises Ankit Shrivastava, regional head, channel sales, eSSL Pvt Ltd.

One should also check the resolutions available in the market. The higher the resolution, the better the quality and the clarity of the image.

Thermal sensitivity is another important feature, which is often referred to as NETD (noise equivalent temperature difference). This is a measurement of the temperature difference detected by a thermal imaging camera. In general, the lower the thermal sensitivity of a camera, the better it will be at detecting smaller temperature differences. This also aids in providing a better image as the different colours of the palette will be better defined.

Knowing a camera’s lens size, estimated spot measuring size and FOV (field of view) are important to arrive at the correct thermal assessment. Generally, the smaller the spot size and the more thermally sensitive the camera is, the better the accuracy. 

Electronics Bazaar, South Asia’s No.1 Electronics B2B magazine