II-VI Coherent uncoated ZnSe optical window

Product Description

High-Quality II-VI (Coherent) Uncoated ZnSe Optical Window – 1″ Diameter x 2.5mm Thick

This is a pristine, surplus uncoated zinc selenide (ZnSe) optical window manufactured by II-VI Incorporated (now part of Coherent Inc.) , a leading producer of high-performance infrared optics . With a standard 1-inch (25.4 mm) diameter and approximately 2.5 mm thickness, this flat optic is designed for broadband transmission in the infrared spectrum, making it an excellent choice for demanding optical systems.

ZnSe’s cubic crystal structure provides exceptional optical clarity with low absorption (<0.0005 cm⁻¹ at 10.6 µm) and high thermal conductivity, ensuring reliability in high-power applications . The uncoated surfaces offer flexibility for users to apply custom coatings tailored to specific wavelengths, while the high damage threshold of the bare substrate makes it ideal for high-power laser systems .

Note: II‑VI Incorporated is now Coherent Corp., and this optic represents the same premier-grade material used in their current manufacturing .

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Key Specifications

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Material Advantages – Laser-Grade Zinc Selenide

Zinc Selenide is the material of choice for demanding CO₂ laser and thermal imaging applications due to its unique combination of properties:

• Broadband IR Transmission: Transmits from 0.6 µm (visible red) to 22 µm (far-IR), covering all key IR bands including the 3-5µm MWIR and 8-14µm LWIR atmospheric windows .

• Low Absorption: Exceptionally low absorption coefficient (<0.0005 cm⁻¹ at 10.6 µm) minimizes thermal lensing and power loss in high-power CO₂ laser systems .

• High Thermal Shock Resistance: ZnSe can withstand rapid temperature changes, making it suitable for high-power applications .

• Non-Hygroscopic: Unlike some IR materials, ZnSe does not absorb moisture, ensuring long-term stability .

• Visible/NIR Transmission: Its partial transmission in the visible spectrum (600-900nm) allows for easy alignment with HeNe lasers (633nm) or other visible guide lasers, simplifying system integration .

Important Safety Note: ZnSe is a toxic material. Always handle with rubber or plastic gloves to avoid contamination. Wash hands thoroughly after handling. Never ingest or inhale dust .

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The Value of Uncoated Optics

This window is uncoated, offering several advantages:

• Custom Coating Flexibility: End-users can apply custom AR coatings tailored to specific wavelengths (e.g., 3-5µm, 8-12µm, or broadband) for enhanced performance .

• High Damage Threshold: Uncoated ZnSe has a very high laser damage threshold, ideal for high-power laser applications where coatings might fail .

• Cost-Effective: Acquire a premium II-VI substrate and apply your own coatings, saving money while maintaining design flexibility.

With natural surface reflectance of approximately 17% per surface, an uncoated window like this transmits >68% at 10.6µm. Applying a broadband AR coating (Ravg ≤0.5% @ 8-12µm) can boost transmission to over 99% .

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Applications

CO₂ Laser Systems (10.6 µm) :

• Protective windows for laser cutting, engraving, and medical systems

• Beam splitters and output couplers

• Its low absorption and high thermal shock resistance make it ideal for high-power CW and pulsed lasers .

Thermal Imaging and FLIR :

• Windows for thermal cameras operating in the 8-14 µm LWIR band

• Protective covers for forward-looking infrared (FLIR) systems

Infrared Spectroscopy :

• Windows for gas analysis cells and sample chambers

• FTIR spectroscopy accessories

Medical and Diagnostic Equipment :

• Non-contact thermometry and thermal imaging systems

• Laser medical devices operating at IR wavelengths

Aerospace and Defense :

• IR sensors and missile guidance systems

• Night vision and surveillance equipment

Research and Development :

• High-temperature process monitoring

• Remote sensing and astronomy

• Laser beam delivery and analysis

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Condition

PRISTINE – UNUSED
NO DEFECTS, SCRATCHES, OR CHIPS
INSPECTED AND VERIFIED FLAWLESS
READY FOR IMMEDIATE USE

⚠ CRITICAL HANDLING NOTE: ZnSe is a soft, toxic material . Always wear gloves when handling . Never touch optical surfaces. Clean only with isopropyl alcohol and lint-free cloth using proper optical cleaning techniques. Avoid drops or contact with hard surfaces.