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Custom Multispectral ZnS IR Window | Cleartran FLIR Grade, DLC + BBAR Coating, 8-12μm LWIR






Product Overview
This 75mm diameter multispectral ZnS infrared window adopts Cleartran (FLIR grade) zinc sulfide substrate, designed for 8~12μm long-wave infrared band. One side is deposited DLC hard carbon coating following MIL-C-48497A / TS-1888 specification for scratch, abrasion and environmental resistance; the opposite side features BBAR broadband anti-reflection coating, delivering average transmittance ≥95% across 8–12μm. Strict optical figure and scratch-dig standards guarantee stable imaging performance for thermal imaging and infrared detection equipment.
Core Specifications
| Item | Parameter |
|---|---|
| Material | Multispectral ZnS (Cleartran / FLIR grade optional) |
| Dimension | Dia 75.0mm (+0.00/-0.10mm), Thickness 5.0mm (±0.10mm) |
| Clear Aperture | ≥67.5mm (>90%) |
| Surface Figure | λ/4 @632.8nm |
| Surface Quality | 60/40 or 40/20 scratch/dig |
| Outer Coating | DLC hard carbon coating, MIL-C-48497A / TS-1888 |
| Inner Coating | BBAR anti-reflection coating, Tavg ≥95% @8–12μm |
| Working Band | 8~12μm LWIR |
Key Features
- Dual coating design: DLC for mechanical protection + BBAR for high infrared transmission
- Cleartran multispectral ZnS, low scatter, suitable for FLIR thermal camera
- Precision diameter & thickness tolerance for tight housing assembly
- High clear aperture ratio, maximize effective infrared receiving area
- Optional premium 40/20 scratch dig for high-end infrared detection system
- Resist abrasion, sand, moisture and salt fog for outdoor & airborne IR systems
Typical Applications
- LWIR thermal imaging camera & FLIR observation system
- Infrared detection, perimeter surveillance & EOIR turret optical protection
- Optical protective window replacement for IR sensor assemblies
- Industrial thermal inspection and rugged outdoor infrared optics
Full Range of Custom Infrared Optical Components
Our in-house manufacturing covers a complete portfolio of infrared optical components, including ZnS, ZnSe and Germanium domes, lenses and optical windows in a wide range of diameters and specifications. All components can be customized with wavelength-targeted IR coatings and precision optical finishing to match your exact system requirements.
Our Service Advantages
- Custom optical specifications available upon drawing request
- Provide official material datasheet and coating test report
- Full coating inspection before shipment, transmittance & surface check
- Stable production lead time for prototype and volume orders
- Support custom size, alternative coating and surface quality upgrade
In-House Precision Polishing & Coating Workshop
All infrared optics are machined, polished, coated and inspected in our dedicated clean workshop with professional grinding, polishing, vacuum coating and optical metrology equipment. Strict in-process quality control ensures consistent surface quality, coating performance and dimensional accuracy for every prototype and production batch.
Frequently Asked Questions
A: Cleartran is multispectral grade ZnS, compared with standard ZnS, it has lower scattering and better visible + IR transmission, widely known as FLIR grade substrate for high-performance thermal optics.
A: DLC stands for Diamond-Like Carbon. It is a hard protective coating for the exposed outer surface, featuring excellent anti-scratch, sand erosion, rain and salt fog resistance. It looks dark matte with low reflection.
BBAR means Broadband Anti-Reflection coating. It is a multilayer dielectric film on the inner sealed side. It reduces infrared reflection to raise average transmission ≥95% at 8–12μm, with colorful interference reflection under light. BBAR is optical-performance oriented but not scratch-resistant.
| Item | DLC Coating | BBAR Coating |
|---|---|---|
| Function | Hard protection, anti-erosion & scratch | Reduce reflection, boost IR transmission |
| Installation Side | Outer, exposed environmental side | Inner, sealed camera cavity side |
| Abrasion Resistance | Excellent | Poor, easy to scratch |
| Appearance | Dark grey matte, low reflection | Colorful interference tint |
A: Yes. We can customize BBAR wavelength range, and upgrade scratch dig from 60/40 to 40/20 for high-end infrared systems.
A: This is flat infrared protective window, not hemispherical dome. Please confirm mechanical interface with your optical housing before ordering.
Request Quotation or Datasheet for 75mm Multispectral ZnS IR Window
Send your drawing, quantity and required specs, we will reply with formal quotation and coating test specification.
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Get Free RFQCustom Precision Optical & Glass Components Manufacturer – Felix Glass Co., Limited.
We supply Industrial Glass, Sapphire Optics, Optical Lenses/Prisms/Filters, Infrared IR Optics, Functional & Display Glass, N-BK7/H-K9L Optical Glass, supporting OEM mass production and laboratory custom prototypes. Flexible MOQ & free sample service available. Fill in the form to download full datasheets and get factory wholesale price within 24 hours.
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- What is the minimum order quantity for custom precision optical glass components?
FELIX OPTICAL GLASS offers highly flexible MOQs to support customer projects, including prototype testing, small-batch trial orders, and high-volume production. All products can be fully customized to your drawings, tolerances, and application standards. Please send us your specifications, and we will reply within 1-5 hours and provide an accurate quotation after careful evaluation within 1-2 days.
- Can I get free glass samples for testing before bulk order?
Yes, our FELIX GLASS factory supports sample testing for a wide range of precision optical glass components and assemblies. The lead time for sample production is 3 to 7 working days. Please contact us today to arrange samples and obtain a customized solution that meets your needs.
- What is the production lead time for custom optical glass components?
A: The production cycle for standard samples is 3-10 working days, while mass production requires 15-35 working days, depending on the complexity of the product and the order quantity. We provide reliable precision optical glass components and fast delivery services for orders from industries such as defense, industrial equipment, medical devices, shipbuilding, robotics, automotive, and aerospace. Please submit your project details so we can provide you with an accurate delivery schedule.
- Are your optical glass products ISO, CE and RoHS certified?
All precision optical glass components from FELIX OPTICAL GLASS comply with ISO quality system standards as well as CE and RoHS requirements. We provide comprehensive test reports, spectral graphs, material certificates, and inspection documents for customer review. Please feel free to request complete certification details and a formal quotation at any time.
- Do you offer one-stop custom optical glass processing services?
Yes. We offer a full range of precision optical glass component processing services, including CNC machining, precision grinding, optical polishing, chemical/physical tempering, vacuum coating (AR anti-reflective coating, AF anti-fingerprint coating, AG anti-glare coating, IR infrared coating), and screen printing. From raw materials to finished products, every step is completed in our own factory. Please tell us your needs, and we will provide you with the most cost-effective solution.
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With 19 years of experience as a precision optical glass expert, we provide comprehensive and satisfactory customized solutions.
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