Eyewear Geometry Lab

Eyewear Geometry Lab

Explore frame geometry, fit, and optical performance with interactive tools for eyewear designers an

Frame Sizing and Fit

Frame Index Calculator

Calculate the average of lens width, bridge width, and temple length to classify frame size (S/M/L).

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Lens Area Ratio

Analyze lens surface area relative to frame outline for optical balance and aesthetic weight.

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Pantoscopic & Face Form Angles

Compute the vertical and horizontal tilt of eyewear frames to optimize fitting and lens alignment.

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Frame PD Calculator

Calculate frame center distance (lens width + bridge width) and compare with wearer’s pupillary distance.

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Frame Fit Index

Assess how well a frame fits based on head width, bridge width, and temple spread angles.

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Temple Spread Angle

Estimate temple opening angle to balance tension and comfort for different head shapes.

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Golden Ratio Check

Evaluate whether your frame’s width-to-height ratio aligns with the golden ratio (1.618).

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Lens Effective Diameter (ED)

Determine the maximum diagonal of a lens shape — critical for lens blank selection.

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Eyewear Frame Manufacturing

Acetate Frame

Calculate how many pieces acetate front could be cut from particular acetate sheet.

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Acetate Temple Calculator

Calculate how many pair acetate temples could be cut from particular acetate sheet.

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Eyewear Frame Inspection

Eyewear AQL

Simulate eyewear inspections, track defects, and visualize sample results interactively.

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Global Eyewear Standards & Compliance

At Shim Sight Eyewear, our engineering philosophy is rooted not only in innovation but also in adhering to the world's most rigorous eyewear manufacturing standards. The reference table below outlines key benchmarks across major markets, ensuring that every ShimSight product meets the highest levels of quality, safety, and performance.

RegionStandard CodeStandard NameScopeKey Requirements Summary
InternationalISO 12870Ophthalmic optics — Spectacle frames — General requirements and test methodsMetal, Plastic FramesDimensional stability, corrosion resistance, flammability, mechanical strength
InternationalISO 8980-1Ophthalmic optics — Uncut finished spectacle lenses — Part 1: Specifications for single-vision and multifocal lensesPrescription LensesRefractive power, prismatic power, material and surface quality, transmittance
United StatesANSI Z80.1Ophthalmic Optics - Prescription LensesPrescription LensesOptical properties, physical properties, refractive power tolerances
United StatesANSI Z80.3Nonprescription Sunglass and Fashion EyewearSunglasses, Fashion EyewearUV protection, refractive power, impact resistance, flammability
European UnioEN ISO 8624Spectacle Frames Measuring System and TerminologyFramesMeasuring system for spectacle frames and related terminology. It is applicable to fronts which are intended to be symmetrical.
European UnionEN 1836Personal eye protection - Sunglasses and sunglare filtersSunglassesUV protection, transmittance requirements, strength, labeling
European UnionEN 14139Ophthalmic optics - Spectacle frames - General requirements and test methodsFramesBiocompatibility, nickel release, mechanical properties
European UnionEN ISO 14889Ophthalmic optics - Spectacle lenses - Fundamental requirements for uncut finished lensesPrescription LensesMaterial specifications, optical properties, durability and marking
Australia/New ZealandAS/NZS 1067Eye and face protection - Sunglasses and fashion spectaclesSunglasses, Fashion EyewearUVR requirements, luminous transmittance, refractive error, robustness
ChinaGB 10810.1Spectacle lenses - Part 1: Single-vision and multifocal lensesPrescription LensesRefractive and prismatic power tolerances, material and surface quality
ChinaGB/T 14214Spectacle frames - General requirements and test methodsFramesMechanical stability, appearance quality, nickel release
JapanJIS T 7331Spectacle frames - General requirements and test methodsFramesSimilar to ISO 12870, with specific national amendments
JapanJIS T 7315Ophthalmic lenses - Uncut finished spectacle lensesPrescription LensesQuality and performance specifications for finished lenses