The HIS2000R-A300-6 operates on the same resistive thermal emission principle as all HIS series emitters. Electrical current through the 40 mm² NiCr filament raises its temperature to approximately 630 °C; the nanostructured surface radiates energy across a broad Planck-governed spectrum. The gold-plated reflector captures rear-hemisphere radiation and redirects it forward through the sapphire window, recovering energy that would otherwise be absorbed by the TO-8 package walls.

The soldered sapphire window transmits radiation across 2–6 µm with high efficiency. Sapphire’s multi-phonon absorption cut-off near 6 µm limits the transmitted band to this range, filtering out longer-wavelength emission. Within the 2–6 µm band, sapphire provides low and spectrally flat absorption loss, ensuring a clean, predictable transmitted spectrum. The soldered seal forms a true hermetic closure rated to withstand repeated thermal cycling and mechanical stress without delamination — a critical advantage for instruments subjected to temperature excursions during operation, storage, or transport.

The nitrogen fill eliminates internal oxygen and moisture, removing the two primary degradation pathways for the NiCr filament at operating temperature: oxidative attack and moisture-driven corrosion of internal surfaces. Pulsed modulation at up to 4 Hz supports lock-in detection in NDIR systems, suppressing thermal background and 1/f noise to improve signal-to-noise ratio and long-term measurement stability.

Highest Signal Budget in a Hermetically Sealed Package

The HIS2000R-A300-6 delivers ~800–1000 mW of optical output within the 2–6 µm band — far exceeding the 135 mW of the hermetically sealed TO-39 HIS550R-A, which uses the same sapphire window but the smaller 11 mm² element. This level of output within a sealed package is unique in the HIS series, enabling optical path lengths and detection limits that would otherwise require open-package emitters with their associated lifetime and environmental limitations.

Soldered Sapphire Window: Maximum Seal Integrity

Sapphire is the preferred infrared window material where mechanical robustness and hermetic seal integrity are the priority. Its Mohs 9 hardness makes it resistant to scratching and mechanical damage; its chemical inertness means it is unaffected by acids, alkalis, moisture, and most solvents encountered in industrial environments. The soldered window-to-package bond maintains hermetic integrity through the repeated thermal cycling encountered in instruments that are powered on and off over years of service — a reliability standard that adhesive-bonded windows cannot consistently match.

Optimised for the 2–6 µm NDIR Detection Band

The 2–6 µm spectral range contains the fundamental absorption features of the most commercially important NDIR target gases: CO₂ at 4.26 µm, CO at 4.67 µm, CH₄ at 3.31 µm, and the C-H stretching bands of hydrocarbons in the 3.0–3.5 µm region. By concentrating all transmitted power within this band, the sapphire window ensures that every milliwatt of output is relevant to the detection task, rather than spreading power across wavelengths with no corresponding absorption feature.

Large 40 mm² Radiating Element

The 40 mm² element generates total radiant flux approximately 3.6× greater than the 11 mm² elements of the HIS550R series at equivalent temperature and emissivity. This large emitting area also provides higher source étendue, improving optical coupling efficiency into multipass cells, large-aperture gas cells, and collection optics with wide acceptance angles.

Gold-Plated Reflector for Near-Lossless IR Recovery

Gold maintains reflectivity above 98% across the 2–20 µm band and does not form infrared-absorbing oxides. The integrated reflector captures rear-hemisphere emission from the filament and directs it forward through the sapphire window, ensuring that the full benefit of the large element area is realised in the transmitted output.

Nitrogen Fill for Long-Term Stability

The nitrogen fill displaces reactive species from the package interior at manufacture. Combined with the soldered hermetic seal, this creates a stable internal environment that prevents filament oxidation and surface corrosion throughout the device’s service life. The result is lower output power drift, extended calibration intervals, and reduced maintenance costs in long-term field deployments.

Patented Nanostructured High-Emissivity Surface

Emissivity exceeding 0.9 ensures near-blackbody spectral behaviour, maximising the conversion of electrical power into radiant flux and producing a spectrally smooth, predictable output. This simplifies filter selection, inter-unit calibration, and system design.

Robust TO-8 Package with Pulsed Operation

The TO-8 package provides greater thermal mass, improved heat dissipation at 2.5 W drive power, and a wider flange for secure mechanical mounting compared to the TO-39 platform. Modulation at up to 4 Hz supports synchronous lock-in detection, enabling noise rejection and improved measurement stability in precision instruments.

• Long-Path and Multi-Pass NDIR Gas Analysis: Very long optical path cells and multipass configurations (Herriott, White cell) for trace-level detection of CO₂, CO, CH₄, and hydrocarbons in applications that require both maximum signal budget and long-term sealed-package stability.
• Stationary Industrial Gas Analysers: High-accuracy fixed-point and extractive gas monitors in petrochemical, pharmaceutical, cement, and steel manufacturing where continuous long-term operation in harsh environments makes hermetic sealing a requirement.
• Environmental and Emissions Monitoring: CEMS and stack emission monitors targeting CO₂, CO, and hydrocarbon species in the 2–6 µm band, where instruments are permanently installed in outdoor or semi-outdoor enclosures subject to temperature cycling and humidity.
• Automotive and Engine Exhaust Certification: High-precision exhaust gas analysers and engine test bench instruments requiring both the signal budget for demanding optical paths and long-term output stability for reference-quality measurements.
• Mid-Infrared Spectroscopy: Laboratory and process FTIR instruments and dispersive IR analysers operating in the 2–6 µm band where a hermetically sealed, high-power source reduces contamination risk and simplifies instrument maintenance.
• Medical and Clinical Gas Analysis: High-accuracy capnography, respiratory gas monitors, and multi-gas clinical analysers where the combination of high output and sealed stability supports both sensitivity and long service intervals between calibration.
• Scientific Research Instrumentation: Custom spectrometers, gas reference cell systems, and optical bench experiments requiring a sealed, high-power, stable infrared source in the 2–6 µm molecular fingerprint region.

United Spectrum Instruments (USI) is a specialist distributor and application partner for advanced photonics, infrared sensing, and scientific instrumentation in India. USI combines access to globally leading component technologies with deep domain expertise, supporting customers from initial product selection through OEM system integration and volume production supply.

Key reasons to work with United Spectrum Instruments:

• Access to internationally leading infrared emitter and photonics technologies
• Expert application support for high-power NDIR gas sensing, FTIR, and industrial IR system design
• OEM consultation covering component selection, optical system design, thermal management, and production ramp
• Reliable supply for evaluation samples and production quantities
• Established partnerships with leading international photonics manufacturers
• Fast, responsive technical communication and application-focused engineering guidance