The mechanical shutter is an internal reference which the microbolometer requires to compensate on e.g. pixel drifts. Basically it is a black reference which is put in front of the detector, which takes reference images and corrects the pixel drift.

By factory default the shutter is initialized when the temperature at the detector changes by 0,5°C. An additional timing elapse function is also implemented and can also be activated. When a camera has just been started it will get to his working temperature. During this time the detector will warm-up and will be shuttered several times to assure the quality of the image.

Today our XTM cores and Gobi cameras have microbolometer detectors on board which utilize a mechanical shutter.

NETD is one of the most important performance parameters for infrared imaging systems. It is a signal-to-noise figure which represents the temperature difference which would produce a signal equal to the camera’s temporal noise. In human language: NETD expresses the minimal resolvable temperature difference when the camera is used for relative imaging applications.

The thermal time constant τth of a bolometer is determined by the thermal mass C and by the thermal conductance G between the pixel and its environment. It expresses the physical time a bolometer needs to heat up and give an electrical output that equals or represents the input. Typical values for A-Si are between 7 and 10ms.

Researchers are exploring novel materials, device architectures, and fabrication techniques to address the technical challenges in single photon detection. This includes the development of new materials, such as 2D materials or perovskites, improved detector designs, advanced signal processing algorithms, and innovative cooling and shielding techniques. By pushing the boundaries of what is possible in single photon detection, researchers aim to unlock the full potential of this groundbreaking technology for a wide range of scientific and industrial applications.

Single photon detection has potential applications in a wide range of fields, including quantum communication and computing, biomedical imaging, LIDAR, astronomy, and remote sensing.
 

Current single photon detection technologies often struggle to achieve high performance across all relevant metrics, such as sensitivity, timing resolution, spatial resolution, and spectral resolution, without compromising on other aspects of detector performance.

Quantum Efficiency (QE) is a key objective in the development of single photon detectors, as it directly impacts the overall performance of the device.

The main challenges in single photon detection include:

• Detection efficiency: The detection efficiency refers to the probability of a photon being detected by the detector. Achieving high detection efficiency is crucial in single photon detection applications. The efficiency depends on factors such as the detector technology, photon wavelength, and optical coupling efficiency. Maximizing detection efficiency is essential for capturing the highest possible number of photons.
• Timing resolution: Many applications involving single photon detection require precise timing information, such as in time-correlated single photon counting (TCSPC) or quantum cryptography. Achieving high timing resolution is challenging, as it requires fast electronics and detectors with short response times to accurately capture the arrival times of individual photons.
• Spatial resolution
• Spectral resolution
• Environmental and operating conditions
• Integration and scalability: In some applications, there is a need for miniaturized or integrated single photon detectors. Challenges arise in developing compact, robust, and efficient detector designs that can be integrated into complex systems or small-scale devices while maintaining high performance.