The rise of photonics in a miniaturised world

Micro moulding is playing a foundational role in the evolution of photonics. Where traditional machining and assembly techniques struggle with miniaturisation, material limitations, and scalability, micro molding steps in as a versatile, cost-effective, and highly repeatable solution. Brett Saddoris discusses this in depth and looks at the considerations that should be taken into account when looking at precision photonics

The world is increasingly defined by photonics. As our appetite for faster, smaller, and more efficient technologies grows, so too does the importance of manipulating light with extreme precision. Photonics is no longer confined to the realm of academic research or cutting-edge laboratories. Today, it powers our communications, drives innovation in healthcare, enables next-generation sensors, and pushes the limits of quantum technologies. And at the heart of many of these breakthroughs are micro-molded polymer components.

As we look to the future, it is clear that micro moulding is playing a foundational role in the evolution of photonics. Where traditional machining and assembly techniques struggle with miniaturisation, material limitations, and scalability, micro moulding steps in as a versatile, cost-effective, and highly repeatable solution.

The broader trend driving growth in photonics is one of convergence. As optical technologies merge with electronics, mechanics, and fluidics in devices like LiDAR systems, biosensors, and AR/VR headsets, component footprints shrink and integration complexity grows. The industry needs miniature parts that deliver on precision, optical clarity, thermal stability, and alignment consistency, all at scale.

Photonics components often require tight tolerances in the range of a few microns, along with complex geometries that support light guiding, reflection, or transmission. Traditional methods like CNC machining or hand assembly not only become cost-prohibitive at this scale but can also introduce unacceptable inconsistencies. Micro moulding, in contrast, offers the precision and throughput required for both development and production environments.

Optical grade plastics and their advantages

One of the key enablers of micro moulding in photonics is the use of optical-grade polymers such as COC, COP, PMMA, and polycarbonate. These materials offer excellent light transmission, low birefringence, and strong dimensional stability, all critical for photonics applications.

Whether it’s the housing of a miniaturised laser assembly, alignment features in an optical connector, or custom lenses moulded directly into components, micro molding allows for the efficient and repeatable replication of highly detailed structures. Multi-functional parts can be produced in a single step, reducing the need for secondary processes and increasing assembly speed.

These advantages are especially important for consumer electronics and automotive applications, where high volumes and extreme reliability are non-negotiable. As demand grows for miniaturised cameras, infrared sensors, and gesture recognition systems, the scalability and repeatability of micro molding provide a critical manufacturing edge.

Alignment, tolerances and the photonic challenge

In photonics, everything begins and ends with alignment. Light is unforgiving. Even a deviation of a few microns in a connector sleeve or lens array can lead to signal loss, reflection, or thermal instability. Micro moulding must achieve not only dimensional accuracy but also repeatability across thousands or millions of parts.

A successful photonics-focused micro moulding process requires deep collaboration between designers and tooling engineers. Critical tolerances must be understood early, and gating strategies, parting lines, and material flow must be optimised to support optical performance. Simulation tools, process monitoring, and in-house metrology are essential, not as add-ons, but as integral parts of the production chain.

We often see customers underestimate the complexity involved in molding for photonics. The challenge is not just about getting light through a part, it is about maintaining control over that light over time, temperature, and usage. Long-term reliability is just as important as first-pass yield.

Typical applications

Micro moulded parts are increasingly central to a variety of photonic systems:

• Optical Connectors & Transceivers: Used in high-speed data transmission, these parts must support precise fibre alignment and minimal insertion loss.
• Miniature Lenses & Lens Arrays: Moulding allows for the direct integration of lenses into device housings or carriers, reducing the need for manual alignment.
• LiDAR Systems: Found in autonomous vehicles and drones, LiDAR systems require lightweight, thermally stable, and optically clear parts with complex geometries.
• Biosensors & Lab-on-a-Chip Devices: In biomedical diagnostics, moulded microfluidic channels and optical windows support light-based detection methods.
• Wearables & AR/VR: Optical waveguides, alignment frames, and light guides are moulded to fit into compact, ergonomic consumer designs.

Each of these applications presents a unique set of challenges, from managing part shrinkage in asymmetric geometries to ensuring ultra-clean molding environments for sensitive optical surfaces.

Meeting the demand for volume

While the photonics sector is often associated with high-end, low-volume applications, that reality is changing. As photonics become embedded into everyday products (from smartphones to smart glasses to health monitors) the need for high-volume, low-defect manufacturing is rising sharply.

Micro molding bridges this gap by offering:

• Ultra-tight tolerances
• High reproducibility
• Ability to use high-performance polymers
• Economies of scale over long production runs

Over the next few years, demand is expected to grow not only in core telecommunications and sensing sectors but also in consumer electronics, industrial automation, and biomedical imaging. Companies that invest early in photonics-optimised micro moulding processes will be better positioned to bring next-generation products to market faster and more reliably.

Summary

Photonics represents one of the most exciting frontiers in modern manufacturing, and micro moulding is its silent workhorse. As systems become more integrated and device footprints continue to shrink, micro molding offers the repeatability, scalability, and performance required to keep pace.

For OEMs and product developers navigating this space, the takeaway is clear. Success in photonics will be increasingly tied to the ability to manufacture small, complex, and optically precise parts at scale. That means choosing partners who understand the physics of light, the properties of high-performance polymers, and the intricacies of moulding at the micron level.

The future of photonics is bright.

Brett Saddoris is Technical Marketing Manager at Accumold.