Customized Step Glass Windows Manufacturer

Precision-engineered stepped glass windows designed for demanding optical and instrument applications.

Product Overview

What Is a Step Glass Window?

A step glass window is a precision optical component featuring one or more machined steps -- discrete, flat surface levels separated by controlled vertical offsets. Unlike standard flat windows, the stepped geometry allows the component to serve as both an optical element and a mechanical datum, enabling precise assembly positioning within instrument housings.

The step profile is created through CNC grinding, lapping, and polishing processes, achieving optical-grade surface quality across all faces simultaneously. This eliminates the need for separate spacers or shims, reducing part count and improving system alignment repeatability.

At Winson Optics, we manufacture step glass windows from sapphire, fused silica, BK7, and other precision optical glasses, with full-surface coating capability and 100% dimensional verification before shipment.

Schematic cross-section -- not to scale

Multi-Step Capable

Up to 4 discrete step levels per component

100% Inspected

Every part verified before shipment

Production Samples

Customized Step Glass Windows -- Real Production Samples

Every piece shown below was manufactured in our Shenzhen cleanroom. No CGI renders -- what you see is what we reliably deliver at mass-production scale.

Precision Step Profile Custom Dimensions AR / AG / AF Coating Options Sapphire & Optical Glass

Step Glass

Technical Specifications

Precision Parameters

All specifications are achievable within our standard production capability. Custom tolerances available upon request -- submit your drawing for a free feasibility assessment.

Dimensional

Outer Dimensions	2mm - 300mm
Overall Thickness	0.5mm - 50mm
Step Height Range	0.1mm - 20mm
Step Height Tolerance	±0.005mm
Lateral Dimension Tol.	±0.01mm
Number of Steps	1 - 4 levels

Optical Quality

Surface Flatness	λ/10 - λ/4 @ 632nm
Surface Roughness (Ra)	< 0.5nm
Scratch-Dig	10-5 / 20-10 / 40-20
Parallelism	< 10 arcsec
Perpendicularity (steps)	< 30 arcsec
Clear Aperture	> 90% of diameter

Materials & Coatings

Substrate Materials

Sapphire (Al₂O₃) Fused Silica N-BK7 Borosilicate N-SF11 ZnSe (IR) CaF₂

Available Coatings

AR (Anti-Reflection) R < 0.2% per surface

DLC (Diamond-Like Carbon) Hardness 9H+

HR (High Reflectance) R > 99.5%

ITO (Conductive) Rs 10-100 Ω/□

Custom specifications welcome. The parameters above represent our standard production range. If your application requires tighter tolerances, non-standard geometries, or specialized materials, submit your drawing or requirements -- our engineering team will respond within 24 hours with a feasibility assessment and quote.

Applications

Where Step Glass Windows Are Used

Step glass windows solve a specific engineering challenge: combining optical transmission with precision mechanical registration in a single component.

Step glass window in microscopy and imaging systems

Microscopy & Imaging

Used as cover windows and field stops in high-NA objectives and confocal systems. The step provides precise axial positioning of the optical element within the objective barrel.

Confocal Microscopy Machine Vision Fluorescence

Laser Systems

Output couplers, beam dumps, and laser cavity windows where the step geometry seals the cavity housing while maintaining precise optical path length. Fused silica preferred for UV applications.

UV / VIS / NIR Output Couplers Cavity Windows

Step glass window in medical and diagnostic devices

Medical Devices

Endoscope distal windows, OCT probes, and in-vitro diagnostic instrument optics. Sapphire step windows offer biocompatibility and scratch resistance for reusable instruments.

Endoscopy OCT Probes IVD Instruments

Semiconductor Inspection

Wafer inspection and metrology tools requiring zero-distortion transmission windows with mechanical registration features. Fused silica for DUV compatibility.

Wafer Metrology DUV Inspection AOI Systems

Step glass window in defense and aerospace optical systems

Defense & Aerospace

Ruggedized sapphire step windows for targeting pods, FLIR sensors, and airborne reconnaissance systems. Withstands extreme thermal cycling and vibration environments.

FLIR Sensors EO/IR Systems Targeting Pods

Step glass window in industrial sensors and spectroscopy

Spectroscopy & Sensing

Flow cell windows, Raman probe tips, and absorption cells where the step provides a hermetic sealing shoulder. CaF₂ and ZnSe for mid-IR spectroscopy applications.

Raman Probes Flow Cells Mid-IR / FTIR

Why Winson Optics

The Procurement-Minded Manufacturer

Most optical factories are optimized for production, not for the buyer's experience. Winson was built differently. Our co-founder Iris brings 12 years of professional procurement experience -- she has sat on your side of the table. That perspective is embedded into every process, from RFQ to delivery.

Drawing-to-Delivery Traceability

Every lot ships with full dimensional inspection reports, material certs (CoC), and coating performance data. No chasing paperwork.

24-Hour Engineering Response

Submit your drawing or requirements today -- our optical engineers provide a technical feasibility assessment and preliminary quote within one business day.

Prototype → Mass Production Continuity

Same facility, same tooling, same QC team from your first prototype to your 10,000-piece production run. No supplier switching risk.

RoHS & REACH Compliant

ISO 9001 certified with full EU compliance documentation. Simplify your incoming inspection and regulatory approval process.

Winson Optics cleanroom manufacturing facility in Shenzhen

10+

Years Manufacturing Precision Optics

200+

Global B2B Clients Served

99.8%

Production Yield Rate

±5μm

Step Height Tolerance

FAQ

Common Questions from Engineers & Buyers

What information do you need to quote a step glass window?

At minimum: overall dimensions (OD/length × width), step height(s) and lateral step position, material preference, surface quality requirement (scratch-dig or Ra), and quantity (prototype + target production volume). A 2D drawing (PDF or DXF) is ideal. If you don't have a drawing, describe your application and our engineers will help define the specification.

What is the minimum order quantity (MOQ)?

We accept orders from 1 piece for prototyping and R&D validation. For production runs, there is no fixed MOQ -- pricing is tiered by quantity. We are designed to support your full product lifecycle, from first prototype through high-volume production, with the same team and tooling.

Can you apply coatings to all faces of a step window, including the step riser?

Optical coatings (AR, HR, partial reflectance) are applied to the flat optical faces. The step riser (vertical wall) can receive a black absorbing coating or be left uncoated. If your application requires coating on the riser, please specify -- we will evaluate the geometry for coating uniformity feasibility. DLC hardness coatings can be applied conformally to all surfaces.

What is the typical lead time for a prototype?

Standard prototype lead time is 7 - 21 business days depending on material availability, geometry complexity, and coating requirements. Expedited service (5 - 10 days) is available for BK7 and fused silica. Sapphire prototypes typically require 14 - 21 days due to material preparation. Contact us with your timeline and we will confirm feasibility.

How do you verify step height accuracy? What documentation is provided?

Step height is measured using a calibrated contact profilometer and/or CMM (coordinate measuring machine) with resolution to 0.1μm. Every shipment includes a dimensional inspection report (actual measured values vs. drawing nominal), material certificate of conformance, and coating performance report (spectrophotometer scan). For regulated industries, we can provide additional traceability documentation upon request.

Which material should I choose for my application?

Material selection depends on your wavelength range, environment, and budget:

·Sapphire -- Best for harsh environments, scratch resistance, UV-NIR (0.15-5.5μm), biocompatible. Premium cost.
·Fused Silica -- Excellent for UV and laser applications (0.18-2.5μm), low thermal expansion, high laser damage threshold.
·N-BK7 -- Cost-effective for visible range (0.35-2.0μm), standard choice for most imaging applications.
·CaF₂ / ZnSe -- For mid-IR and far-IR spectroscopy applications.

Not sure? Describe your application and we will recommend the optimal material.