Compare Model Drawings, CAD & Specs Availability Price
LightIR 18-225mm f/4
MWIR Continuous Zoom Lens, LightIR, 18-225 mm FL, f/4, High Durability
LightIR 18-225mm f/4
MWIR Continuous Zoom Lens, LightIR, 18-225 mm FL, f/4, Low Reflection Hard Carbon

WFOV (18 mm)

Pitch 640x512 1280x1024
15 µm 29.9°
10 µm 20.2° 39.1°

NFOV (225 mm)

Pitch 640x512 1280x1024
15 µm 2.4°
10 µm 1.6° 3.3°


  • Type
    Continuous Zoom
  • Focal Length
    18-225 mm
  • F/#
  • Spectral Range
    3.4-4.9 μm
  • Cold Stop FPA Distance
    19.4-20.5 mm
  • Cold Stop Clear Aperture
    Ø4.88 mm
  • Back Focal Length
    26.9mm in air (with 1+0.5mm Ge windows)
  • Minimum Focus Range
    5 m Wide, 50 m Narrow
  • Nuc (by defocus)
  • Focus Mechanism
  • Focus Time
    <2 s
  • Zoom Mechanism
  • Zoom Time
    <5 s
  • Weight
    326 g
  • Dimensions
    Ø61.4 x 84 mm
  • Drive Voltage
    12 V
  • Current Consumption
    0.5 A average, 1.0 A peak
  • Communication Interface
  • Operating Temperature Range
    -32ºC to +75ºC
  • Storage Temperature Range
    -54ºC to +85ºC
  • Sealing
    IP67 front element only
  • Wavelength Region


LightIR 18-225mm f/4.0 Detection, Recognition & Identification (DRI) Range

DRI ranges enable one to easily estimate the maximum range that an object can be either detected, recognized or identified. It is important to note that these estimates are based solely on geometrical parameters – the target size, distance, lens focal length and camera detector pixel size. Signal level, detector sensitivity, atmospheric conditions and other factors are not considered!

The calculations used here are based on the “Johnson Criteria”. According to the Johnson Criteria, the minimum resolution, pixels on target, required to achieve a 50% probability for an observer to discriminate an object are:

  • Detection: An object is present – 2 pixels on target (Lower Bar)
  • Recognition: discern the type of object, a human vs. a vehicle – 8 pixels on target (Middle Bar)
  • Identification: discern specific objects, a man vs. a woman, a car model – 12.8 pixels on target (Upper Bar)

LightIR 18-225mm f/4.0 Zoom Lens

High Performance Mid-Wave Focal Plane

Using advanced technologies, top-quality materials and unique coating techniques, together with innovative engineering and opto-mechanical designs, we have earned a reputation for excellent performance, durability and quality.

High-durability and Hard-carbon AR Coatings

Our highly abrasion-resistant, anti-reflective advanced optical coatings include several types of Hard Carbon coatings which provide maximum durability, energy transmission & minimal reflection. Our innovative coating technologies include:

  • Physical Vapor Deposition (PVD) – Thermal heating and electron gun
  • Ion Assisted Deposition (IAD) – Ion gun
  • Plasma Enhanced Chemical Vapor Deposition (PECVD) for DLC coatings

Passive Athermalized Lens Assembly

Our IR imaging lens assemblies incorporate passive athermalization of the lenses and opto-mechanical system to maintain the highest imaging performance over the full operating temperature range. We use advanced materials that enable unique athermalization properties and optomechanical designs that effectively compensate for optical variations over a wide temperature range.

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