Ophthalmic Testing Services

NSL Analytical’s Lens Testing Analysis

Linear Abrader

Our optical test laboratory is equipped with an ISO 8980-5 type linear abrader that can be configured for concave or convex surfaces and either abrasion resistance testing or cleanability. Moreover, the weight can be adjusted on the instrument to simulate applied pressure.

Contact Angle

NSL utilizes a drop shape analyzer from KRÜSS. We can measure the surface tension by placing a drop of water or oil on a coated surface. This testing provides the effectiveness of hydrophobic and oleophobic properties of the coating.

QUV

The QUV accelerated weathering tester exposes materials to alternating cycles of UV light and moisture at controlled, elevated temperatures. It simulates the effects of natural sunlight and artificial irradiance using special fluorescent UV lamps in the UVA, portion of the spectrum. We can reproduce the damage that occurs over months or years to test the durability of materials.

Artificial Perspiration

To replicate real world effects NSL uses perspiration is readily for use with the ophthalmic laboratory’s QUV oven. When applied to a lens surface, NSL can determine the effect perspiration has on the lens coatings, the lamination junction points or on the lens substrate itself.

Lens Mapping

Our A&R Dual LensMapper (DLM) provides customers with sharp and accurate measurement of all lens designs. The DLM combines two optical technologies (Reflection and Transmission) for a fast, accurate and automatic measurement.

Outputs include values, maps and profiles in terms of SPH, DPT, CYL & AXIS.

Through power range: -10D to 10D
Convex surface power range: +1D to +10D (index 1.525)
Concave surface power range: -3D to -12D (index 1.525)
Accuracy to within .02D background
Measurement area = 35x40mm for the through power, 30X35mm for the front power

The DLM is the perfect tool to achieve a very high level of optical quality control from SV to Free Form lens design.

Consulting

As an Independent Testing Laboratory, NSL Analytical can also provide objective third-party analysis of your laboratory.

Test Protocols

NSL’s Enhanced Simulated Wear Test (ESWT)
Hard Coated Lenses
AR Coated Lenses
VSP Test Protocols
- VSP Protocol A: PAL Design
- VSP Protocol B: Hard Coat
- VSP Protocol C: Hard Coat & AR Coating
- VSP Protocol D: Photochromic
- VSP Protocol F: Blue Light Filtering

Manufacturing Assistance, Technical Support, Troubleshooting, Defect Analysis, and Custom Formulation

We can provide services for improving the cleaning, coating, and curing processes of your manufacturing operations. Once a confidentiality agreement is in place, we will review those coating processes that are presenting challenges to your operations after which we will report our findings and offer our suggestions for improvement.

Our team has personally encountered almost every imaginable coating defect. We use state-of-the-art analytical technology to identify the defect, determine the root cause or causes, and then implement permanent as well as practical solutions quickly and correctly.

Looking to improve the yield, throughput, or other efficiency aspects of your operation? For more information about our Technical Services and Consulting capabilities, please feel free to complete an online information request.

Frames and Accessories – Regulatory

NSL also tests Frames and Accessories which are subject to regulatory standards

EU Nickel Release
CPSIA
CA Prop 65
Chemical Resistance
Heavy metal content testing – Nickel, Lead, Cadmium, Mercury
Phthalates
BPA

The Vision Council

Are you a member of the Vision Council? Special rates available here!

Enhanced Simulated Wear Test

Consumers are hard on their glasses, and they expect them to keep up with everyday life. Do your lenses have problems with scratches, smudges and cleanability? NSL Analytical’s Enhanced Simulated Wear Test (ESWT) answers the call.

NSL Analytical has developed a test with the wearer in mind. ESWT uses scientific, quantifiable and repeatable procedures to evaluate lens coatings. The test simulates actual wear such as scratching and cleanability – the two primary consumer concerns – while including baseline measurements on adhesion, delamination, peeling and transmission.

Prove your lens coating stands out in the marketplace.

View NSL Analytical’s New Performance Evaluation Test

ESWT+

The ESWT testing can be customized with ESWT+, a Statistical Analysis Package, to provide further understanding and benchmarking of the test results and can be very effective to understand the performance of lens coaters to assist in comparison of different locations.

Ophthalmic Photochromic Testing

NSL’s ophthalmic photochromic testing helps clients bring their products to market faster.

Take pride in developing a product that is the best, NSL Analytical can provide the data to prove it.

NSL works with companies to bring their products to market faster by testing to ISO 8980 Part 3. Get a market comparison of your lenses with:

Speed of Activation
Speed of Deactivation
T ½ time
Temperature Dependence

Regulatory Testing

The eye wear industry is undergoing strict regulations for restrictive substances in their products. So, customers work with NSL to take advantage of our full range of manufacturer frame and accessory regulatory testing services. NSL Analytical understands and applies appropriate regulations thanks to our advance ophthalmic testing services.

Consumer Product Safety Improvement Act

Especially in products designed for children.

Lead (Pb) can be found in bright paint colors of eye glass cases, lanyards, packaging, cleaning cloths and frames
Phthalates (chemicals used to soften plastic) can be found in children’s toys and childcare articles, temple tips and nose pads in glasses.
According to regulations periodic testing must be performed by a CPSC-accepted third party laboratory.

Visit our Regulatory Testing & Compliance page for more information

CA Prop 65

The California Proposition 65 statute states that no person in the course of doing business shall “knowingly and intentionally expose any individual to a listed chemical” without first giving a clear and reasonable warning. The governor of California is required to publish annually a list of chemical substances that the state has determined to either cause cancer or cause birth defects or other reproductive harm.

This is law of due diligence for any accessory or frame: labeling, knowledge and testing.
Products must be identified and labeled as harmful.
Manufacturers need to know what’s in their product.
Products must be tested for quality control.
Heavy metals like Lead (Pb), fire retardants, and plasticizers such as phthalates can tested and identified to existing in a product.

Nickel Release Testing

NSL Analytical performs Nickel Release Testing including EN 16128-2011 test & EN 1811-2011 test to comply with European Union Directive.

European Union Directive 2004/96/EC

Because nickel and its compounds may cause allergic contact dermatitis, the directive states that its use must be limited in products that come in contact with the skin. NSL offers nickel release testing services in compliance with the latest test requirements.

European Union Restrictions on Nickel

Nickel may not be used	Unless
1. In any post assemblies that are inserted into pierced ears and other pierced parts of the human body	The rate of nickel release from such post assemblies is less than 0.2 µg/cm2/week (migration limit)
2. In products intended to come into direct and prolonged contact with the skin, such as earrings, necklaces, wrist-watch	The rate of nickel release from the parts of these products coming into direct and prolonged contact with the skin is less than 0.5 µg/cm²/week for at least two years
3. In products listed in point 2 above where these have a non-nickel coating	Such coating is sufficient to ensure that the rate of nickel release will not exceed 0.5 µg/cm²/week for a period of at least two years of normal use of the product.
4. Products in points 1, 2, and 3 may not be placed on the market	They conform to the requirements set out above.

To comply with the Directive, the following tests are mandated:

EN 16128-2011 is a chemical test specifically for spectacle frames and sunglasses that measures the release of nickel ions into a chemical that mimics human sweat.

EN 1811-2011 is a chemical test to that measures the amount of nickel ions released from products that are inserted into pierced parts of the human body, as well as items that come into direct and prolonged skin contact.