Infrared Detectors and Modules
for the spectral range 2-16 µm
The unique functionality of VIGO products is highly appreciated, especially in the volatile analyser market. The detectors are used to monitor process gases in the chemical, refinery, power generation, food and aerosol industries. Photodiodes and photoresistors operate as part of highly sensitive optoelectronic analysers whose radiation source is medium- and long-wavelength quantum cascade lasers (QCLs). Devices with VIGO detectors are used as electronic “noses” – they can measure very small concentrations (ppb and ppt) of chemical substances in a mixture. In addition to analysing process gases, such systems are ideal for analysing unwanted vapours, such as pollutants and hazardous or flammable compounds, as well as for quality control – to detect leaks and spills. An invaluable advantage of optical detection modules is their insensitivity to electromagnetic interference. Such devices can be left in hazardous areas and measurements can be taken from a safe location.
Control and Calibration of the laser power
Powerful laser sources, mainly high-power CO2 lasers and solid-state lasers, have been used for many years for fast and precise processing of hard materials, large-scale cutting, engraving, cleaning and welding. These sources operate in the mid-infrared range because the high absorptivity of this type of radiation allows materials to be altered by heating without contact. A natural consequence of this situation is the demand for sensors that operate in the same spectral range as lasers and allow control of beam power and position. VIGO System offers a wide range of long-life IR detectors optimised for the wavelength range from 2 to 16 µm. The fabricated structures are characterised by low heat capacity and insignificant influence of the thermal signal on the optical signal. Different sizes of active area are available depending on the customer’s requirements. The VIGO research team also develops linear or square multi-component detectors, which are ideal for positioning radiation sources.
Real-time water quality control
Access to clean drinking water is still a luxury for many of the world’s inhabitants. Even in areas where H2O is abundant, there is a problem with analysing the substance before it is consumed. In addition, the risk of deliberate poisoning of water reservoirs by terrorist groups is increasing, which, combined with the slow functioning of conventional liquid analysis instruments, can mean that the danger is not detected quickly enough. The current situation is set to change thanks to the WaterSpy project, which is co-operated by VIGO System. This project, which involves 9 European companies, is developing technology for the photonic analysis of liquids. The device under construction, which will be both accurate and handy, consists of fibre-coupled QCLs and detectors supplied by VIGO System. Thanks to the use of ATR spectroscopy, a very good signal-to-noise ratio should be achieved and the method will not require any pre-cleaning of the samples before measurement. Considering the current state of work, we can say that VIGO System’s detectors will soon ensure the supply of clean and refreshing water to citizens.
Analysis of the temperature distribution in fast moving objects
The unbeatable speed and sensitivity of VIGO System’s detectors make them useful for applications where response time is a matter of the safety of hundreds of people and possible failures and delays can result in huge monetary losses. One of the main applications of the PV photodiodes, which are at the heart of the detection modules, is measuring the temperature of train sets. There are several types of heat sensors on the market, but VIGO System’s unique products outperform the other devices based on pyroelectric bodies, bolometers and thermocouples in terms of response time, detection limit and resistance to external conditions. The detectors installed in the devices between the rails allow non-contact real-time measurement of the temperature of wheels, brakes, shock absorbers and undercarriages of train sets. Information about possible overheating is immediately forwarded to the responsible authorities. The detectors are also used to scan all rolling stock before a train enters a tunnel. The undeniable advantages of VIGO System’s products have led to them being used throughout Europe to protect train passengers.
There are high hopes that the detectors of the VIGO system will serve well in medical applications. Suffice it to say that the Polish sensors enable absolutely non-invasive blood analysis. Successful trials have been documented to measure oxygen saturation, blood flow and even glucose levels, with an error rate comparable to that of conventional glucose meters. All this was achieved with the help of infrared detectors that analyse the spectrum of laser radiation reflected from parts of the human body that are supplied with large amounts of blood.
Es gibt auch kommerziell erhältliche Geräte auf dem Markt, die die von VIGO System entwickelten Technologien nutzen. Es handelt sich dabei um Geräte zur Analyse der Ausatemluft. Sie ermöglichen die Bestimmung des Gehalts an Tumormarkern oder die Diagnose von Asthma oder Lebererkrankungen. Solche Geräte können auch zur Überwachung der Luftzusammensetzung in Operationssälen eingesetzt werden. Darüber hinaus werden die von VIGO System gelieferten Detektoren zur Kontrolle der Leistung und Positionierung von Laserstrahlen verwendet, die von Chirurgen, Zahnärzten oder Dermatologen eingesetzt werden.
Ever stricter standards for the content of carbon dioxide, nitrogen oxides and dusts in car exhaust gases are forcing vehicle manufacturers to use precise and reliable gas analysers. This creates a demand for spectroscopes that guarantee the highest accuracy. To meet the demands of the market, VIGO System offers HgCdTe detectors that are perfectly suited for spectral analysis and have high sensitivity in a wide wavelength range from 2 to 16 µm. They enable the detection of all fuel combustion products, as the absorption lines of the substances sought fall within the range of wavelengths detected by the devices. In this way, the concentrations of CO2, CO, NOX and hydrocarbons can be monitored. Thanks to the excellent sensitivity, resolutions of a single ppm or even ppt can be achieved, which means an ultra-precise estimate of the trace amount of a substance. It is worth highlighting that the detection limits of the VIGO instruments are in the top range worldwide and reach the basic BLIP limits.