| Supplier 01 | Request the spectral-transmittance curve, stated filtering range, lens material, refractive index, available powers, and sample lenses. Confirm whether filtering is achieved by coating, material, or both. | Ask for applicable test reports and confirm the product category and test methods. ISO 8980-3 covers transmittance specifications and test methods for spectacle lenses; confirm the applicable edition and scope. | Confirm prescription range, coating options, edging support, sample lead time, and production capacity in writing. | Confirm quotation validity, minimum order quantity, packaging, shipping terms, warranty, and defect-resolution process. |
| Supplier 02 | Compare clear and tinted options using measured spectral-transmittance data; do not rely on a “blue cut” label alone. Ask how the filtering claim is measured and reported. | Request reports traceable to the supplied lens type and production lot. ISO 8980-1 addresses specifications for uncut finished single-vision and multifocal spectacle lenses; verify applicability to the order. | Check available base curves, diameter, prescription range, coating combinations, and tolerance documentation against the buyer’s specification. | Ask for a named technical contact, response-time expectations, sample approval procedure, and written replacement terms. |
| Supplier 03 | Request separate data for each material and coating combination. Check visible light transmittance, color appearance, reflections, and any effect on lens clarity. | ISO 14889 specifies fundamental requirements for spectacle lenses. Ask which requirements are claimed for the finished product and obtain supporting documentation. | Verify whether the supplier supports custom powers, stock lenses, private-label packaging, and pre-shipment inspection. | Confirm whether samples are production-equivalent, who pays sample and freight costs, and how transit damage is handled. |
| Supplier 04 | Ask for data on UV protection separately from blue-light filtering. Request the measurement method and avoid treating these as interchangeable claims. | Check that any conformity or test report identifies the actual model, material, coating, and relevant market requirements; a certificate alone may not establish product performance. | Confirm available lens designs, power range, coating durability test information, and lot-level traceability. | Ask for production milestones, order-change deadlines, export packaging details, and escalation contacts. |
| Supplier 05 | Compare the supplier’s stated filtering curve with the buyer’s target wavelength range. There is no single universally applicable blue-light cutoff for all spectacle lenses. | Request the full report, laboratory identity, test date, test conditions, and report number; independently confirm the report where practical. | Verify color consistency, coating options, lens marking requirements, and the supplier’s process for handling nonconforming lots. | Compare payment terms, delivery estimates, tracking support, and the documented procedure for claims and returns. |
| Supplier 06 | Request samples in the intended prescription and coating where possible. Check transmitted color and appearance under consistent lighting conditions. | Confirm that reports cover the ordered lens configuration, not merely a different material or uncoated sample. | Ask for documented inspection criteria for power, cylinder, axis, prism, cosmetic defects, and coating defects as relevant to the order. | Check the process for sample approval, repeat orders, urgent orders, and corrective action after a quality issue. |
| Supplier 07 | Ask whether filtering performance is specified as a curve or a single percentage, and request the underlying measurement data for meaningful comparison. | Check standards and regulatory requirements for the destination market and intended use. Sunglass standards such as ISO 12312-1 apply to sunglasses, not automatically to ordinary clear spectacle lenses. | Confirm compatibility with the buyer’s frame and edging requirements, plus stock availability and stated production lead times. | Ask how shipping dates are calculated, what export documents are provided, and whether shipment insurance is available. |
| Supplier 08 | Request evidence supporting any claims about glare reduction, visual comfort, or screen use; distinguish measured product properties from health or outcome claims. | Verify whether the quality system certificate is current and applies to the manufacturing site and scope relevant to the ordered product. | Ask about lot coding, retention samples, in-process checks, and whether independent pre-shipment inspection is permitted. | Confirm label and packaging customization, artwork approval, language options, and any associated setup charges. |
| Supplier 09 | Compare materials, refractive indices, lens designs, and coating choices against the buyer’s intended price and performance requirements. | Request a product specification sheet and verify that stated values and tolerances match the purchase order and inspection plan. | Check order capacity, production scheduling, process change notification, and written controls for substitutions. | Compare communication quality, quotation detail, order confirmation accuracy, and support after delivery. |
| Supplier 10 | Use a buyer-defined specification for filtering, material, prescription range, appearance, and packaging; require written confirmation before ordering. | Validate the applicable standards, destination-market rules, and test evidence for the precise product. Do not infer compliance from marketing language. | Agree on acceptance criteria, inspection sampling, traceability, and a corrective-action process before production begins. | Compare total landed cost, confirmed lead time, after-sales commitments, and remedies for late, damaged, or nonconforming goods. |