Key Advantages of Transfer-Molded Packaging

Improved Optical Performance
Transfer-molded packages allow for integrated primary optics, enabling tightly controlled lens profiles for beam shaping, collimation, and fiber- or aperture-coupling. This is particularly valuable for RCLED and QWLED point-source emitters, where sub-millimeter optical alignment is required for measurement, medical, aiming, and sensing applications. The molding process also provides excellent control over emitter-to-lens alignment, ensuring that the optical axis is precisely maintained from unit to unit—critical for applications requiring tight beam symmetry or long-distance projection. Transfer-molded materials can be engineered for high UV, visible, or IR transmission, enabling improved radiant flux output and enhanced optical efficiency. In addition, the package structure reduces internal reflections and minimizes angular variation, resulting in more uniform and predictable emission profiles. Furthermore, phosphor additives can be incorporated directly into the molding compound to convert or broaden the LED’s native emission spectrum, enabling tailored spectral outputs—such as multi-band, white-light, or application-specific wavelengths—without the need for external filters or secondary optics. 

Detection performance can also be optimized using a transfer-molded photodiode package. For instance, transfer-molded packages allow for integrated primary optics, enabling tightly controlled lens profiles for beam shaping, collimation, and coupling. In addition, the transfer-molded photodiode package minimizes stray light, reduces parasitic reflections, and maintains tighter alignment tolerances, resulting in higher signal-to-noise ratio and more accurate detection. It also provides consistent optical geometry and mechanical stability, ensuring repeatable responsivity and improved low-light performance. Transfer molded packaging can reduce parasitic capacitance because epoxy molding compounds typically have a lower dielectric constant (εr ≈ 3.5–4.5) compared to ceramic, glass-to-metal seals, or large metal package volumes. By reducing parasitic capacitance and enhancing thermal dissipation, transfer-molded photodiode packages further enable faster response times and greater precision in demanding sensing applications—all within a compact, reliable, production-scalable form factor. Furthermore, when the molding compound is formulated with optical filtering characteristics, it can function as an integrated bandpass or notch filter, selectively transmitting or blocking specific wavelengths to enhance detection accuracy in targeted spectral bands.

Better Reliability and Environmental Robustness
Mechanical stability is also enhanced, as the molded compound encapsulates and protects the LED die, improving vibration resistance and long-term reliability in harsh environments. Wire bonds in conventional, non-encapsulated packages can fail by lift-off (wire debonding) or wire fracture due to mechanical stress from vibration, impacts, and thermal cycling. A monolithic molded package structure protects the die and wire bonds from shock, vibration, thermomechanical fatigue, and water ingress, resulting in enhanced durability and more consistent performance across temperature and mechanical extremes. This makes optoelectronic transfer molded packaging technology an ideal choice for automotive, industrial, aircraft, and defense-grade requirements.

Low Profile, Compact Footprint, and Dense Packing
Transfer-molded SMD optoelectronic packages offer a significantly smaller footprint than many conventional SMD LED and photodiode package styles because the optical and mechanical structures—such as lenses, light shields, and housings—are formed directly in the molded body rather than added as separate plastic components. By eliminating bulky reflector cups, multi-part lens caps, and oversized lead frames, transfer-molded packages can achieve tight lateral dimensions and low profiles, often in standard JEDEC outlines optimized for automated pick-and-place.

This reduced footprint enables much denser component packing on printed circuit boards (PCBs), supporting higher channel counts in sensing arrays, more compact illumination modules, and miniaturized instrumentation. As electronics continue to shrink in size and increase in functional complexity, the compactness of transfer-molded SMD optoelectronics provides a critical advantage—allowing designers to integrate more optical functionality into smaller form factors without sacrificing performance or reliability.

Manufacturing Consistency and Cost Efficiency
Compared to liquid or manually formed encapsulants, transfer molding provides repeatable geometry, minimal unit-to-unit variation, and scalability for high-volume production. Once tooling is in place, the process yields lower per-unit cost with tight control over height, planarity, lens radius, and package outline.

Availability
Engineering prototypes are planned for release in early 2026, with full production availability beginning in Q2 2026. Transfer-molded photodetector, and LED packages will be available in select JEDEC and IPC SMD footprints. Custom sizes and optical geometries can be developed to OEM design specifications. Additional potential photonics packaging variations include options for integrated lenses, phosphor layers, filter windows, and light shielding. Initially, chip sizes up to 350 µm × 350 µm can be packaged. Our new transfer-molded packaging is suitable for emission and detection from 355 nm to 2300 nm.

Engineering samples and custom design engagements are welcome upon request.
In the U.S. contact: Marktech Optoelectronics
Email: [email protected]

In Japan and International Locations contact Optrans Corporation
Email: [email protected]

About Marktech Optoelectronics
Marktech Optoelectronics, headquartered in Latham, NY, specializes in the design, testing, and manufacturing of optoelectronic components, including LEDs, emitters, detectors, and custom assemblies. Marktech partners closely with engineering teams to provide performance-optimized photonic solutions tailored to specific application needs. Website: https://marktechopto.com

About Optrans Corporation
Optrans Corporation, located in Kawasaki-Shi, Japan, is a high-precision optoelectronic device manufacturer with advanced semiconductor processing, assembly, and optical packaging capabilities. Optrans supports high-reliability and high-performance optoelectronic production for global customers across sensing, instrumentation, industrial, and medical markets. Website: https://optrans.co.jp

Visit Our Booth at Photonics West 2026 to Learn More About Our Photonics Packaging Capabilities

Plan now to visit our booth (#259) at SPIE Photonics West, 17 – 22 January 2026 in San Francisco, California to help us celebrate 40 years of photonics innovation.
SPIE Photonics West is the optics and photonics industry’s flagship exhibition to meet the sector’s biggest names and learn about the latest innovations.

Learn more: https://spie.org/PW

See our PW26 company listing: (https://spie.org/ExhibitorDetail?ExpoID=5022&ExhibitorID=104424)

For Media Inquiries Contact:
Gary J . Kardys, Marktech Optoelectronics,
Email: [email protected]