Eight Channel Pyroelectric Detector in TO8 Housing
Pyroelectric detectors are ideally suited for gas analysis. Until now, it only gets complicated if many gases should be measured. There are often simply too few measuring channels for this purpose. The LRM-278 from InfraTec offers exactly the right solution for this. This detector combines eight measuring channels in a TO8 housing with a diameter of 15.2 millimeters. As a result, the number of gases that can be measured with a single detector of this size doubles in one fell swoop.
Double Space Savings
When looking at the design of the single supply detector, two details become clear, which make a significant contribution towards ensuring that such a powerful solution fits into such a small space. The first detail is the central window built directly in the cap, which all other models of the series of miniaturised multi channel detectors have, too. The correspondingly large aperture of 8.5 × 8.5 mm2 means that the LRM-278 has a very large field of view (FOV). This gives rise to its outstanding signal-to-noise ratio.
The second detail is concealed inside the detector. There, on special chip carriers, the sensitive pyroelectric sensors, the compensation elements as well as the 2 × 2 mm2 filters are positioned directly on top of each other. Due to this stack design, there is sufficient space for all other components.
The Space-saving Wonder
Further Features of LRM-278
Central window built directly in the cap
FOV: 80°
Pyroelectric chips: 1.4 x 1.4 mm2 per channel
Filters: 2 x 2 mm2
Detectivity: 4.5E+08 cm√Hz/W
Temperature sensor integrated in the detector
Single supply OpAmp for current mode
Thermal compensation available
Completely hermetically sealed on request
Temperature Sensor Directly in the Detector
The frames with sensitive elements and filters are arranged in a square each with three times three fields. With a total of eight channels, one field thus remains free – the one in the middle. At this position there is a temperature sensor. With gas sensors, the temperature is usually measured as well. Until now, this has not been possible directly in the detector, however. Measuring the temperature inside the detector, for example, provides the option of compensating the typical temperature drift of the filters very accurately by means of a calibration.
In addition to the measurement accuracy, there are also the benefits resulting from the current mode of the LRM-278. This means that it impresses particularly by its fast displaying of signal changes and dynamic response behaviour. The resulting high signal voltage simplifies the circuit design and allows the detector to become more resilient against disturbances. The higher signal levels support the easy integration of the detector into measuring modules.
Possible Applications
Complex tasks within the gas analysis
Analysis of medical and technical gases
Measurement of emissions
Safety technology
Would You Like to Know More?
It is not unusual for tasks to be associated with special requirements. Discuss your specific application needs with our experienced engineers, receive further technical information or learn more about our additional services.
LRM Series: Miniaturized Multi Channel Detectors
LRM detectors by InfraTec offer an extremely wide FOV in combination with a compact design and attractive pricing. Their central window in the cap provides reliable protection against environmental influences. Optionally soldered to the housing it enables complete hermetic sealing. The channel filters are placed inside the detectors close to the pyroelectric elements. The reduced distance and the central window integrated into the detector caps ensure a wide FOV.
LRM Detectors at a Glance
Assortment of 2-, 4- and 8-channel detectors
Operation in voltage mode or current mode
Extremely wide FOV provides powerful performance
TO46, TO39 and TO8 housings available
Robust central window for protection against penetrating moisture
Thermal compensation available
