Sensor News
The Sensor Division Newsletter from InfraTec
Dear readers,
In our current Sensor News, we take a journey into the past of InfraTec and present our latest innovation, the digital detector. Moreover, you will get some insights into the fields of application of our pyroelectric detectors.
InfraTec – International and Reliable
Together with our business and project partners, we look back on a challenging and exciting year. Our flexible pandemic management and our well-stocked warehouse of raw materials and semi-finished products have enabled us to meet our customers‘ needs at all times, even under the current circumstances of worldwide supply shortages. To meet the increasing demand for detectors, we have expanded our workforce in almost all areas, and not only at our headquarters in Dresden, Germany. This year, we are also strengthened our sales presence in our Shanghai office.
The next few years will also see the challenge of generational change: “We, the owners of InfraTec, are getting older and will now be judged not only by what we achieve every day, but how we manage to make the next generation of owners and managers work optimally at InfraTec,“ says managing director Dr. Matthias Heinze on the subject of corporate succession.
We hope you will find many interesting insights and findings while reading the latest Sensor News.
Read in this Issue
30 Years of Infrared Technology at the Highest Level
More than three decades ago, ambitious graduates of the Technical University (TU) of Dresden founded the company InfraTec. Unknown as a start-up, they faced numerous challenges, as there were no products ready for series production, manufacturing and testing technologies, or even customers.
Nevertheless, they mastered every hurdle with solid expertise, commitment, as well as patience and led InfraTec onto the international market. Today, 30 years after its founding, InfraTec is a globally respected producer in the field of infrared technology, with subsidiaries in the UK, the USA and China.

This success story began in the basement of the former kindergarten of the TU Dresden, where the first detectors were developed and produced. Shortly afterwards, the young company moved to the premises of the TechnologieZentrumDresden and began developing and producing compact multi-channel detectors with 2 to 4 channels for gas analysis. With the relocation of the TechnologieZentrum, InfraTec finally also came to the site on Gostritzer Straße and set up the first complete production line for pyroelectric detectors here.
This was the beginning of an almost completely manual production for pyroelectric detectors. In the years that followed, numerous innovative and award-winning technologies from InfraTec were developed. Today, the sensor clean room covers 1,500 m2 and houses the laboratories of the development department as well as state-of-the-art machinery for automated series production. This provides the necessary capacity and accuracy to meet the strictly specified, customer-specific requirements. In the laboratories, InfraTec’s developers and their partners conduct research on novel technologies and pyroelectric materials.
InfraTec will continue to be the strongly customer- oriented company with a focus on technology and quality leadership: Because we live research and technology!
A Glimpse into the History of InfraTec

- 2002 A faster electro-optical testing of all detectors is carried out by automated measuring systems
- 2003 Powerful is a the new class of pyroelectric detectors with an integrated transimpedance amplifier for current operation
- 2004 More resistant to mechanical shock and vibration are the sensitive pyroelectric elements mounted in the detectors by using a patented solution
- 2008 More diverse become the applications for the detectors with tuneable Fabry-Pérót filter
- 2017 Less space is needed for the miniaturised multi-channel detectors
- 2019 The first 8-channel detector in the world is the LRM-278
- 2022 Easier becomes the system integration for the detectors with digital signal output and variable signal processing
Go Digital – Reach Your Goal Faster with Less Effort
Last year, InfraTec introduced its first pyroelectric detector of the PyrIQ family with a digital interface – the 4-channel detector LRD-3824. Like all of InfraTec’s detectors, this one is based on single-crystal lithium tantalate (LiTaO3). This material offers high sensitivity and a good signal-to-noise ratio without additional cooling or temperature stabilisation.
Compared to detectors with an analogue output signal, the digital option already includes the entire pre-processing of the sensor signals. Thus, the sensitivity, the time constants and the dynamic range of each channel can be individually adapted to the requirements of the respective application. The detector’s core, a 16-bit A/D converter, then translates the signal into a digital data stream. There is also a digital filter already integrated into the detector. The LRD-3824 communicates with a connected microcontroller via an I²C interface. Complex amplifier and filter stages, as are necessary for detectors with an analogue output signal, are now not required. All this saves development time, reduces the space requirement of the entire system and simplifies system integration.

Special Features of the Digital Detector
The variable signal processing allows the detector behaviour to be changed even during operation. This offers the user the possibility to adapt the performance of sensitivity and stability to the requirements of the application in the best possible way in every situation.
There is a further optimisation in electromagnetic compatibility (EMC). The digital output signal is less affected by interference radiation than analogue signals. In addition, the entire signal conversion of the detector is spatially concentrated and shielded by the detector housing.
For high-precision measurement, especially in gas analysis, synchronisation of the emitter and detector clock is necessary. For digital pyroelectric detectors of the PyrIQ family, a separate clock input is available for this purpose, via which the system clock or the exact sampling time is specified. This allows a time signal with a highly precise sampling rate to be generated.
Another special feature compared to analogue technology is the “Fast Recovery after Saturation” function. Here, a logic integrated in the detector will detect whether the input signal of the A/D converter is overdriven. This can be caused by a faulty operating condition – for example, by extreme temperature fluctuations or mechanical influences. In this case, the analogue input stage will automatically be reset in order to be available for measurements again within a very short time.
Small but Mighty – The Digital 2-Channel Detector
The LID-2322 combines two spectral channels with a digital output signal in a TO39 housing. It is ideally suited for the use in mobile devices due to its compactness. Together with its low power consumption and thermal compensation, it is the ideal choice when it comes to applications in harsh environments.
To operate the detector, only two other connections are necessary in addition to the connections to the supply voltage. In this way, it can be both parameterised and read out. The external hardware effort is thus reduced to a minimum and the integration of the detector into the application is significantly simplified. A fifth pin, which can be used to specify an external clock, also enables this detector to read out the measurement data at the exact time and to synchronise it with a radiation source.

Various Fields of Application for PyrIQ Detectors
Digital detectors are just as suitable for the use in gas analysis and flame sensing as detectors with analogue signal output. But especially if the environmental conditions require a compact and easy-to-integrate detector, a detector with integrated digitisation will be a good choice.
Thus, among other things, the digital version is suitable for the field of air-conditioning and building technology when it comes to measuring air quality. Since this correlates well with the carbon dioxide concentration in the air, the CO2 content of the room air is used for demand-controlled ventilation control in buildings and rooms. The CO2 concentration is measured according to the principle of non-dispersive infrared measurement technology. For this purpose, suitable IR filters are integrated into the detector in order to be able to make an accurate and reproducible measurement.
This ensures good air quality at all times. In this context, the compactness of the detector, which results from the integration of the entire signal pre-processing, is an advantage. Another benefit is the low sensitivity of the digital output signal to interference caused by mobile phone networks, Bluetooth or wi-fi.
In flame sensor technology, pyroelectric detectors capture spectral ranges that are characteristic for burning organic substances such as wood, natural gas, petrol and various plastics. Flame sensors are used in the fields of industrial fire protection and early fire detection and withstand even the most adverse environmental conditions.
Due to the low interference sensitivity of the digital detector, the risk of false alarms caused by electromagnetic interference sources is significantly reduced.
Further Possible Applications for the Digital Detector:
- Agricultural industry, for example for monitoring the atmosphere in greenhouses and in research projects on plants
- Gas detectors for explosive gases, for example for mining or drilling platforms
- Process gas analysis, for example for measuring exhaust gases in industrial plants
