Compare Model Drawings, CAD & Specs Diameter Antireflection Coating Thickness Parallelism Availability Price
25.4 mm Uncoated 2.0 mm <3 arc minutes
25.4 mm Uncoated 3.0 mm <3 arc minutes
12.5 mm 3-12 µm 2.0 mm <1 arc minutes
20.0 mm 3-12 µm 2.0 mm <1 arc minutes
25.0 mm 3-12 µm 3.0 mm <1 arc minutes
40.0 mm 3-12 µm 4.0 mm <1 arc minutes
zinc selenide optical window model ZNPX15 made with znse
50.0 mm 3-12 µm 3.0 mm <1 arc minutes
zinc selenide optical window model ZNPX15 made with znse
75.0 mm 3-12 µm 6.0 mm <1 arc minutes


  • Material
    CVD Laser Grade ZnSe
  • Surface Flatness
    λ/20 @ 10.6 µm
  • Surface Quality
    40-20 scratch-dig
  • Cleaning
  • Clear Aperture
    10ZS: central 85% of diameter
    ZNW: central 90% of diameter
  • Diameter Tolerance
    10ZS: ±0.2 mm
    ZNW: +0.0/-0.1 mm
  • Thermal Expansion Coefficient
    7.1 x 10-6 K-1 @ 273 K
  • Thermal Limit
    18 W m-1 K-1 @ 300 K
  • Damage Threshold
    <100 kW/cm2 CW @ 10.6 µm, >113 µm spot diameter, <30 s duration


Ideal for Thermal Imaging

Zinc Selenide has low IR absorption, and is transparent across a very wide 0.6-16 µm spectral range. This is advantageous for thermal imaging, where temperatures of remote objects are ascertained via their blackbody radiation spectrum. Long wavelength transparency is crucial for imaging room temperature objects, which radiate at peak wavelength of approximately 10 µm with very low intensity.

3 to 12 µm Broadband Coating

ZnSe has a high index of refraction which requires an anti-reflection coating to achieve high transmission. Our broadband AR.20 coating is optimized for 3-12 µm and can withstand up to 100 kW/cm2 for 10.6 µm CW laser beam with >113 µm spot diameter and <30 sec duration.

Withstands Thermally Demanding Environments

Zinc Selenide windows are ideally suited for thermally demanding environments. The windows are both low in absorption and high in thermal shock, making them usable even in high power CO2 laser applications. These windows may also be used in applications such as IR imaging in scientific, military or search and rescue applications.

Handle With Caution

Zinc Selenide material is formed with extremely high purity by molecular beam epitaxy. It is a soft material, making it resilient and tolerant of thermal shock. It is also a toxic material. Great care must be taken in handling and cleaning the material. Wear gloves at all times to avoid risk of contamination. Hold only the edge to prevent scratches. Wash hands after use.

This is toxic by ingestion and inhalation of dust, with a cumulative effect. It also affects the nervous system. Particular care must be exercised when machining and creating dust or particles. Inhalation of dust may irritate the respiratory system. Acute selenium poisoning produces central nervous system effects, which include nervousness, convulsions and drowsiness. Other signs of intoxication can include skin eruptions, lassitude, gastrointestinal distress, teeth that are discolored or decayed, odorous ("garlic") breath. Chronic exposure by inhalation can produce symptoms that include pallor, coating of the tongue, anemia, irritation of the mucosa, lumbar pain, liver and spleen damage, as well as any of the other previously mentioned symptoms. Chronic contact with selenium compounds may cause garlic odor of breath and sweat, dermatitis, and moderate emotional instability.