SubscribeOptical and electro-optical sensors are a fundamental element of most surveillance, target acquisition and reconnaissance systems.
QinetiQ provides a comprehensive capability for the test and evaluation of commercial and military sensors and systems that spans the visual and long wave infrared wavebands.
- Impartial advice on the specification and evaluation of key parameters.
- Evaluation of individual sensors or multi-sensor systems, including signature measurement.
- Flexible test equipment configuration caters for a broad range of test item formats.
- Impartiality, security and confidentiality are assured.
- QinetiQ staff have accumulated experience of sensors for land, sea and air environments.
- State of the art laboratories suited to prototype or production testing.
The use of high quality optical and electro-optical sensors remains a primary requirement for many commercial and military surveillance applications. The high cost of these systems, particularly when in a multisensor configuration, makes knowledge of the system parameters at the experimental or prototype stage a valuable asset for confirming conformance to specification.
QinetiQ offers a comprehensive test and evaluation service for this class of sensor and can also provide advice and consultancy on sensor performance capabilities and their specification. For your surveillance, target acquisition and reconnaissance requirements, QinetiQ’s experienced staff and its secure and well equipped laboratories provide an ideal combination.
Thermal Imagers
Thermal imager metrics provide a quantitative statement of performance for comparison with specified design capabilities and customer requirements. These vary from system level metrics, used to establish DRI range performance, to detector/module level metrics, to establish quality of detectors. Thermal imager measurements include:
- Minimum Resolvable Temperature Difference (MRTD)
- Minimum Detectable Temperature Difference (MDTD)
- Noise Equivalent Temperature Difference (NETD)
- Operational Readiness Time
- Field of View (FoV)
- Co-incidence of FoV
- Signal Transfer Function
- Dead Pixel Count
Measuring the MRTD of an ALBION focal plane array thermal camera (Gen 3)
Image Intensified Systems
Image intensified night vision systems and helmet mounted displays for air crew and infantry require an understanding of their performance under increasingly demanding conditions. Trade-offs between operational life, low light resolution capability and dynamic range all need to be considered. Image intensified system measurements and procedures include:
- Spectral Sensitivity
- Resolution
- Modulation Transfer Function (MTF)
- Luminous Gain
- Spectral Transmission
- Compatible Lighting (NVIS Radiance – Green/Red Ratio)
- Recovery Time
- Magnification
- Distortion
- Flight Trials
Measuring the MTF of a FENN2000 night vision goggle
Direct View Optics
In addition to the more conventional performance metrics applicable to telescopic instruments and unity vision systems, unusual but critical parameters can be measured. These include the line Strehl ratio as an image quality metric and veiling glare index for forward scatter assessment. Direct view optical system measurements include:
- Resolution
- Line Strehl Ratio
- Modulation Transfer Function (MTF)
- Veiling Glare Index
- Field of View (FoV)
- Spectral Transmission
- Exit Pupil Diameter
- Eye Relief
- Distortion
Measuring the Strehl ratio of an armoured fighting vehicle sight
Television Systems
Television systems are increasingly being used for surveillance roles. Evaluation of their improving performance at low light levels and in non-uniformly lit scenes is required to establish suitability for their intended commercial or military application. Television system measurements typically include:
- Resolution
- Signal to Noise Ratio vs Light Level
- Minimum Resolvable Contrast (MRC)
- Field of View (FoV)
- Veiling Glare
- Accuracy of colour reproduction, including white balance.
Defence Vision Systems gated intensified CCD camera
The Importance of Test and Evaluation
Commercial and military surveillance continues to benefit from developments in sensor technology. For example, thermal imaging capabilities, television systems and displays offer increasing levels of performance in ever more stringent environments.
Evaluation of these sensors and systems to provide confidence in their ability to meet customer requirements plays a vital role in the procurement process. The secure optics and electro-optics laboratories within QinetiQ incorporate measurement equipment for the characterisation of thermal imagers, direct view optics, image intensified systems, television based systems (including displays) and electro-optical signatures. Much of this equipment has been specially developed to measure non-standard parameters and as such offers a unique test environment.
Results from the evaluation of both conventional and unconventional performance metrics enable the practical capabilities of the test item to be compared with its design parameters at an early stage in its development cycle. These results are typically presented to the customer in the form of a commercially confidential written report that, by nature of its impartial content, can form an element of a formal acceptance programme.
QinetiQ and its Customers
QinetiQ is Europe’s largest science and technology organisation formed from the British government’s prestigious Defence Evaluation & Research Agency (DERA). QinetiQ has over 7500 scientists and engineers working to create and apply science and technology to provide winning solutions.
Thisarticle offers an overview of what QinetiQ can contribute to commercial organisations, government and private sector bodies in one area of test and evaluation. With expert staff recruited from multi-disciplinary backgrounds, our breadth of services and technical support is vast.
Our teams have the capability to deliver novel technical solutions, to provide technical advice and to undertake collaborative ventures with global organisations to meet today’s business and technical challenges.
