Eyewear factory step-by-step production process: from design to finished frames

As someone who has overseen the end-to-end manufacture of thousands of frames, I know clients need more than high-level descriptions—they want practical, verifiable guidance they can use when choosing an eyewear factory. In this article I explain the step-by-step production process in a modern eyewear factory, how design decisions affect tooling and costs, what testing and standards matter, and how to accelerate time-to-market without compromising quality.

Design and market research: shaping a product that sells

Trend analysis and target customer

The first step in any successful eyewear program is defining the market positioning: mass volume sunglasses, fashion acetate frames, High Quality metal optical, or sport performance eyewear. I begin by combining consumer trend research, retail sell-through data, and brand DNA. Sources like the Sunglasses and Eyeglasses pages offer useful category context, while regional market reports and your sales history define the SKU mix.

Technical requirements and regulatory constraints

Early technical decisions—prescription vs. plano, polarized vs. standard lenses, impact resistance, UV protection—drive material and process choices. For sunglass filters and safety standards, consider international benchmarks such as WHO guidance on vision health and regional standards (e.g. EN ISO for sunglasses). Documenting lens light transmission, coating specs, and frame durability at the design stage prevents costly rework later.

Design for manufacturing (DFM) and initial CAD

Good designs balance aesthetics and manufacturability. I use CAD to validate wall thicknesses, hinge geometry, and lens seat tolerances. For acetate, TR90 (thermoplastic polyamide), or metal, the details differ: acetate requires allowances for hand-finishing and heat-shrink during tempering; TR90 favors injection molding; metal frames need stamping, welding, and precision machining. Early DFM saves iterations in tooling and shortens ramp-up time.

Prototyping and tooling: from concept to production-ready

Rapid prototyping: 3D printing and soft tooling

Prototyping confirms fit, feel and optical integrity. I typically use SLA/PolyJet 3D prints for form checks, then CNCed master blocks for acetate prototypes. Soft tooling (aluminum molds) can validate injection-molded TR90 parts before investing in hardened steel tooling—this hybrid approach is widely used in the industry to de-risk new SKUs.

Tooling: mold design and master dies

Tooling is the largest up-front investment. For injection molded frames, precision steel molds with conformal cooling reduce cycle time and shrink variance. For acetate, tooling is focused on master blocks and cutting jigs used for milling lens openings and shaping. Proper venting, gate placement and draft angles are critical; I insist on multiple mold trials and first-article inspections before approving production runs.

Time and cost trade-offs

Material and tooling choices determine lead time and MOQ (minimum order quantity). Hardened steel molds offer long life and low per-piece cost at high volumes but higher initial capital; aluminum or soft molds reduce upfront cost with higher per-piece variance. I work with partners to model total landed cost including rework, warranty rates, and speed-to-market to choose the right approach.

Manufacturing: materials, processes and quality control

Frame materials and how they influence production

Different materials require different processes and expertise. Below I compare common frame materials and typical processing paths—this is a practical reference I use when advising clients.

Sources for materials and manufacturing context: Acetate (Wikipedia), Injection molding (Wikipedia).

Key production steps

In a typical eyewear factory the production flow I oversee is:

1. Raw material inspection (pellets, acetate blocks, metal sheets)
2. Molding or blank shaping (injection, stamping, CNC)
3. Rough trimming and drilling for hinges/lens seats
4. Polishing, plating or coating
5. Assembly (hinges, screws, nose pads, lenses)
6. Final optical/lens fitting and inspection
7. Packaging and labeling

Quality control (QC) at each stage

QC cannot be an afterthought. I implement SPC (statistical process control) at molding presses, remove non-conforming lots after visual and dimensional checks, and apply optical tests for lenses (transmittance, polarization, prescription accuracy). For UV protection and coating claims we rely on certified lab tests; where relevant I refer partners to internationally recognized standards such as EN ISO or region-specific regulations. The WHO and industry best practices remind us that protective eyewear claims must be validated.

Finishing, testing and logistics: preparing finished frames for market

Surface treatments, coatings and cosmetics

Finishing is where perception of quality is defined. For acetate that means multi-step polishing and lacquer; for metal it includes plating (PVD or electroplating) and passivation. Lens coatings—anti-reflective, hardcoat, hydrophobic—are applied in controlled clean rooms. I monitor adhesion, haze and cross-cut adhesion as part of final acceptance testing.

Testing for safety and claims verification

Certain claims require lab verification: UV400, polarization, impact resistance (for sports goggles), and prescription tolerances. Regulatory standards vary by market: for example, many regions use versions of the EN ISO standards for sunglasses and spectacle lenses. When exporting, I ensure documentation and test reports are provisioned to customs and retailers to avoid delays.

Packing, serialization and delivery

Packaging must protect products and reflect brand positioning. For high-volume runs I specify bulk inner boxes with protective wraps; for High Quality brands we use custom-branded cases, cleaning cloths, and serialized certificates. I also plan logistics windows around seasonality; a fast-moving sunglass launch requires shorter lead times and flexible production slots.

Performance metrics, sustainability and choosing a partner

Key manufacturing KPIs

I recommend tracking these KPIs for any eyewear program: first-pass yield, defect per million (DPMO), AQL results for incoming materials, average lead time from PO to shipment, and on-time-in-full (OTIF). Regular supplier audits and production reviews move the needle on consistency.

Sustainability considerations

Material selection and process efficiency affect environmental footprint. Recycled acetate, bio-based plastics, and solvent-free finishing reduce impact. Energy-efficient injection presses and water recycling in plating processes contribute to measurable sustainability goals. Brands increasingly request Environmental Product Declarations (EPDs) or supplier sustainability reports.

How to evaluate an eyewear factory

When you visit or audit a factory, look for vertical capabilities (in-house tooling, lens finishing), sample and QC lab facilities, and documentation for standards compliance. I value partners that provide quick prototyping, transparent cost models, and demonstrated export experience to Europe and the Americas.

Case study: balancing speed and quality

Scenario and approach

A client needed a polarized sport sunglass line with custom branding and a 12-week window from concept to retail. We used rapid prototyping to finalize fit in two weeks, soft tooling for TR90 molds to validate performance in week four, and then switched to hardened steel molds for the production run. Early supplier coordination and in-line QC allowed us to meet the deadline without significant rejects.

Results and lessons

The program hit retail on time with a less than 0.8% defect rate in final inspection. Key lessons: (1) invest in front-loaded prototyping, (2) define pass/fail for coatings and polarization up-front, and (3) reserve production slots in your factory partner to avoid seasonal bottlenecks.

Why partner with an experienced OEM/ODM eyewear factory

Established in 2010, Karuson International Co., Ltd. is a premier eyewear factory and global OEM/ODM supplier with over 15 years of mastery in eyewear design and precision manufacturing. Operating two state-of-the-art eyewear factory bases in Dongguan and Guangzhou, we provide high-capacity production and agile delivery cycles to meet the demands of the fast-paced global market.

Our expert team has pioneered 300+ trend-setting designs, ranging from polarized sunglasses and TR90 frames to advanced optical eyewear and sports goggles. As a vertically integrated eyewear factory, we offer end-to-end customization—including bespoke frame engineering, specialized lens technology, and precision logo engraving. By maintaining rigorous quality control and rapid prototyping, we have earned the enduring trust of prestigious brands across Spain, Europe, and the Americas.

Karuson differentiates itself through:

• Vertical integration: in-house tooling, plating, lens fitting and packing to control lead times and quality
• Design strength: over 300 proprietary designs and dedicated trend research
• Advanced manufacturing: CNC, high-precision steel molds, and clean-room coating lines
• Quality assurance: rigorous SPC and third-party lab testing for UV and impact claims
• Global export experience: compliant documentation and logistics support for EU and American markets

We excel in custom glasses, custom glasses lenses, customized sunglasses, custom sunglasses sports, customize sport sunglasses, custom prescription lenses, pc sunglasses, TR sunglasses, metal sunglasses, custom sport sunglasses. For inquiries, contact me at nicole@karusonco.com or visit our website: www.karusonco.com.

Frequently Asked Questions (FAQ)

1. How long does it take to go from design to production for a new eyewear model?

Typical lead time depends on material and tooling choices. For injection-molded TR90 with existing molds, you can expect 8–12 weeks for design finalization, prototyping, mold trials and first production. For new acetate styles requiring block milling and hand-finishing, 12–20 weeks is common. Choosing soft tooling can shorten validation but may increase per-piece variation.

2. What quality tests should I require from an eyewear factory?

Insist on: dimensional checks for frame tolerances, hinge torque and lifecycle tests, lens transmittance and UV testing (lab-certified), impact resistance for sports eyewear, and coating adhesion/hardness. Ask for test reports referenced to recognized standards where applicable.

3. What are the pros and cons of choosing TR90 vs. acetate frames?

TR90: lightweight, flexible, low-cost at scale, ideal for sports. Acetate: High Quality feel, rich color possibilities, preferred for fashion. Consider brand positioning, MOQ, and expected retail price. See the materials table above for a quick comparison.

4. How do you ensure lens prescription accuracy for finished frames?

Prescription lenses are measured with lensometers and interferometers; verification against Rx tolerances is mandatory. For progressives we run additional positional and power mapping tests. We also require incoming lens supplier certificates when outsourcing lenses.

5. Can an eyewear factory handle custom branding and packaging?

Yes. A vertically integrated factory typically offers logo engraving/etching, custom temple printing, bespoke cases, and tailored inner packaging. Make sure to align artwork files, Pantone colors, and material specs early to avoid delays.

6. Which international standards are relevant to sunglasses and optical eyewear?

Standards vary by market; commonly referenced documents include EN ISO series for sunglasses and spectacle lenses. For broader health and safety context, WHO resources on eye health are useful. When in doubt, request factory compliance certificates and third-party lab reports.

Contact and next steps

If you need a reliable eyewear factory partner who can take your concept from sketch to shelf-ready frames, I invite you to reach out. Karuson International Co., Ltd. has the design expertise, manufacturing capacity and QC systems to support large-scale OEM/ODM projects. Email us at nicole@karusonco.com or visit www.karusonco.com to view our catalog and request a quote. Let’s discuss how we can shorten your development cycle and protect KARUSON reputation with professionally manufactured eyewear.

References and further reading: Eyeglasses (Wikipedia), Sunglasses (Wikipedia), Injection molding (Wikipedia), Acetate (Wikipedia), World Health Organization (WHO).