Metrology and Manufacturing Polymer Optics

The optics industry has come a long way in recent years, thanks to advances in computer-aided design, metrology, and polymer materials. Among these, metrology is one of the most important since it verifies the component’s efficacy and ensures that it can perform as intended.

Metrology is a requirement for molding optics. Without metrology, manufacturers have no way to assess the precision and accuracy of optical components. Apollo Optical Systems specializes in metrology and manufacturing polymer optics for numerous applications.

What is Metrology?

As defined by the International Bureau of Weights and Measures, metrology is the science of measurement, embracing both experimental and theoretical determinations at any level of uncertainty in any field of science and technology. ¹

Optical metrology is the science and technology that measures optical components and systems. These measurements can target the light sources, properties of light, or properties of objects, such as distances, dimensions, and temperatures.

Equipment for Metrology and Polymer Optics

All optical components have specifications that are vital to their functionality.

Using  specialized equipment, AOS can measure and confirm optical parameters. This instrumentation includes:

• Zeiss Contura G2 Coordinate Measuring System (CMM): Molded parts are held in a precision custom fixture while a small probe scans the mechanical and optical surfaces. The data provides the location and shape of all surfaces.
• Form TalySurf System: Contact optical profiler that measures the form of optical surfaces, particularly aspheric surfaces.
• Olympus Nomarski Microscope: Magnifies optical surfaces up to 1,000x for viewing surface quality and features. Images can be captured using a color digital camera to provide to the customer.
• Zygo NewView: Scanning white light interferometer that measures surface roughness, step heights, and other topographic features.
• Fisba Optik Phase 2 HR Digital Compact Interferometer: Device that measures surface figure on smaller spherical parts.
• Zygo Interferometer: Device that measures surface figures on larger spherical parts.
• Strainoptics Polarimeter System: Device that measures optical retardation on polarization-critical optical components.

Metrology and Manufacturing Polymer Optics

Custom-designed polymer optics are precision engineered and contain manufactured components that are crucial to performance. Because of this, manufacturing optics requires a lot of planning and forethought to reduce risk.

The best design comes from a comprehensive understanding of the problem and the physical and technological principles necessary for an effective solution.

From initial design to manufacturing and assembly, optical and mechanical design should take place in-house to provide an integrated solution.

At Apollo Optical Systems, we provide:

• Design for manufacture: A unique combination of design and production that allows us to produce systems that work as software and hardware.
• Verification of optical design: We can provide an independent analysis of an existing design to make sure it will meet your needs.
• Tolerance analysis: Our tolerance analysis is a vital component to produce an effective system.
• Imaging and illumination systems: We can design imaging and illumination systems, including beam shaping optics for both LED and laser systems.

Single-Point Diamond Turning

After the design phase, we can use single-point diamond turning (SPDT) for superior optical surface finishes and consistent performance with both plastic and metals. The SPDT process can be used for optical components and to machine the optical surface on inserts during the molding process.

SPDT is capable of machining the following optical surfaces:

• Conics
• Diffractive
• Toroidal
• Fresnel
• Aspheric
• Spheres
• Freeform

Creating optics from polymers involves acrylics, polyetherimide, polystyrene, and COC/COP. SPDT polymers allow rapid prototypes for testing, reducing the overall costs and lead times.

Injection Molding

Injection molding is a common method for producing polymer materials in high volumes for low costs. This process produces consistent, high-quality parts.

Injection molding can produce:

• Microlens arrays
• Diffractive surfaces
• Custom optical diffusers
• Spherical, aspheric, and Fresnel surfaces
• Freeform surfaces
• Prisms

At our metrology lab, we test optical elements produced by both injection molding and SPDT. We test to ensure that all parts perform as they should after integration into your system.

About Apollo Optical Systems

Apollo Optical Systems specializes in precision polymer optical components for consumer, commercial, automotive, medical, defense, and LED lighting markets. Contact us today to get an estimate for your custom optical components!

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