Types of Cooled MWIR Lenses

Cooled Infrared Module | High-Sensitivity MWIR Imaging

A cooled infrared (IR) module is a high-performance electro-optical system that integrates precision infrared optics with a cryogenically cooled detector. By cooling the detector—typically using a Stirling cooler—thermal noise is dramatically reduced, resulting in exceptional sensitivity, higher signal-to-noise ratio (SNR), and superior image quality.

Cooled IR modules are essential in applications where long-range detection, fine temperature discrimination, and high spatial resolution are required.

 

Optical Module Characteristics

  • High-quality infrared optical assemblies with low aberration design
  • Advanced anti-reflective (AR) coatings for high transmittance
  • Integrated Stirling cooling system, ensuring detector stability
  • Optimized opto-mechanical design to manage vibration and thermal load
  • Suitable for MWIR spectral band applications

 

Detector & Optical Parameters

  • Spectral Band: Mid-Wave Infrared (MWIR)
  • Detector Types: InSb, MCT (HgCdTe), or QWIP (depending on configuration)
  • Cooling Technology: Stirling cooler
  • Mounting: Ruggedized structure to support cooling assembly and system integration

 

Integrated Technical Specifications

Detector Options

Resolution Pixel Pitch
320 × 256 30 μm
640 × 512 15 μm
1280 × 1024 12 μm

 

Performance

  • Response Band: 3.7 – 4.8 μm (MWIR)

  • NETD (@20 °C):

    • ≤ 25 mK (320 × 256)

    • ≤ 20 mK (640 × 512 / 1280 × 1024)

  • Frame Rate: 25 Hz / 50 Hz / 100 Hz

  • Cooling Method: Stirling cooled

  • Cooling Time: < 8 minutes (normal temperature)

  • Inhomogeneity: ≤ 0.1% after calibration

 

Interfaces & Control

  • Communication Interface:

    • RJ45 standard network port

    • RS422 serial port

 

Functional Image Controls

  • Synchronization: Internal / External / Automatic

  • Brightness & Contrast: Manual / Automatic

  • Mirroring: Horizontal, Vertical, Diagonal

  • Image Algorithms:

    • Dimming

    • Image enhancement

    • Polarity selection

    • Filtering

    • Non-uniformity correction (NUC)

    • Blind pixel removal

 

Power & Protection

  • Over-voltage protection
  • Over-current protection
  • Under-voltage protection
  • Reverse polarity protection

 

Environmental Adaptation

  • Operating Temperature: −40 °C to +60 °C
  • Storage Temperature: −45 °C to +70 °C
  • Shock Resistance: 30 g, 11 ms half-sine
  • Vibration Standard: GJB 150.16A-2009A, Method 2.3.10

 

Applications

Cooled IR optical modules are widely used in:

  • Military target acquisition & tracking
  • Long-range surveillance and reconnaissance
  • Space and aerospace research
  • Scientific instrumentation
  • Advanced industrial thermal analysis
  • Border security and maritime monitoring

 

How to Select a Cooled IR Module

1. Define the Application

  • Surveillance, scientific research, tracking, or industrial monitoring
  • Required detection range and temperature sensitivity

2. Choose the IR Spectrum

  • MWIR: High sensitivity, excellent contrast, suitable for long-range detection
  • LWIR: Better performance through smoke and haze (if required)

3. Select Detector Format

  • Resolution (320×256 / 640×512 / 1280×1024)
  • Pixel pitch for resolution vs. system size trade-off

4. Cooling Technology

  • Stirling cooler for high-end performance
  • Consider lifetime, vibration, and power constraints

5. Optics Compatibility

  • Match focal length and FOV to detector size
  • Ensure lens materials support MWIR (e.g. Germanium)

6. Image Processing & Interfaces

  • Required onboard processing features
  • Compatibility with Ethernet, RS422, or system controllers

7. Environmental & Mechanical Requirements

  • Operating temperature range
  • Shock and vibration resistance

8. Supplier Support

  • Customization capability
  • Long-term technical support and reliability