In scenarios such as infrared spectroscopy analysis, gas detection, flame monitoring, and industrial temperature measurement, the stable capture of mid-infrared (0.8?3.2 μm) signals is a core challenge in both scientific research and industrial detection. Traditional refrigeration-type detectors require low-temperature cooling, large size, and high cost. However, the Sefan Optoelectronics 7ID4 series of lead sulfide (PbS) detectors, with their core strengths of no need for refrigeration, wide spectral response, high sensitivity and low noise, and plug-and-play functionality, have broken through the technical barriers of mid-infrared detection and become the preferred solution for low-temperature infrared detection.

The 7ID4 series includes two core models: 7ID4321 (domestic chip) and 7ID4302 (imported chip). They precisely cover different application requirements. 7ID4321 achieves an ultra-wide spectral response of 0.8?3.2 μm, with a peak wavelength of ≥ 2.1 μm. The 6×6 mm large photosensitive surface significantly improves the efficiency of light signal collection, with a response degree of ≥ 300 V/W. It is suitable for domestic autonomous scenarios. 7ID4302 focuses on the mainstream wavelength range of 0.8?3.0 μm, with a peak wavelength of 2.2 μm. The 1×5 mm long strip photosensitive surface is suitable for fiber coupling, with a response degree of up to 3×10⁴ V/W, and a detection rate of D* reaching 2.5×10¹¹ cm・Hz¹/²・W⁻¹. Its performance is on par with that of international leading standards. Both models operate at room temperature, without the need for liquid nitrogen or Stirling refrigerators. They can be powered on immediately and are completely free from the complex maintenance and high costs associated with refrigeration systems.

Low noise and high stability are the core competitiveness of the 7ID4 series. The built-in low-noise preamplifier ensures an equivalent input noise of ≤ 1 μV, an input impedance of ≥ 3 MΩ, a working frequency range of 20 Hz?100 KHz, an amplification factor of 50 times, and the ability to easily capture nanowatt-level weak infrared signals. The use of precise sealing and temperature compensation design results in low dark current and minimal baseline drift. The consistency of long-term continuous monitoring data far exceeds industry standards, perfectly adapting to high dynamic range measurement and long-term experimental requirements. The time constant is ≤ 400 μs (7ID4321) / ≤ 200 μs (7ID4302), with rapid response and precise capture of transient infrared signals.

The interface and integration design directly address user pain points. The 7ID4 series adopts standard installation dimensions, is compatible with Sefan's full range of spectrometers, light sources, and detection systems, and comes with a standard SMA905 optical fiber interface. It is plug-and-play, with an energy coupling efficiency exceeding 90%, eliminating free light scattering losses. The entire unit is compact and sturdy, with a small size, low power consumption, and suitable for laboratory portable devices, industrial online detection, and field monitoring scenarios. It can be quickly deployed without complex debugging, significantly reducing system integration costs.

From research to industry, the 7ID4 series application covers all scenarios. In the research field, it helps with infrared spectroscopy analysis, material optical characterization, and infrared testing of two-dimensional materials, with data accuracy improved by 40%; in industrial scenarios, it provides stable signals for gas leakage detection in petrochemicals, infrared temperature measurement of power equipment, and defect screening of semiconductor wafers, with detection sensitivity reaching ppm level; in the security and fire protection field, it supports flame monitoring and perimeter security, quickly identifying hydrocarbon flames with extremely low false alarm rates; in environmental monitoring, it is adapted for greenhouse gas and VOCs exhaust gas detection, achieving non-contact precise measurement.

Sefan Optoelectronics, with its twenty-year accumulation of photonic technology, enables the 7ID4 series lead sulfide detectors to achieve domestic substitution and outstanding performance. Without refrigeration, wide spectral response, high sensitivity and low noise, and flexible adaptation, the 7ID4 series is not only a mid-infrared detection device but also a reliable partner for precise detection. Choosing Sefan 7ID4 is choosing a "stable, accurate, economical, and fast" infrared detection solution, lighting up every moment of precise mid-infrared signals for every scientific exploration and industrial quality detection.