Comfort Beyond Weight Reduction: Three Breakthroughs in VR Headsets Enabled by Miniaturization

Early iterations of Augmented Reality (AR) and Virtual Reality (VR) devices set the stage for a future of immersive experiences from the comfort of home — a vision that was only amplified with the rise of remote interactions sparked by the COVID-19 pandemic and the subsequent emergence of the metaverse. Yet much like the concept of the metaverse itself, the widespread adoption of AR and VR devices has faced significant hurdles. Although their use has increased for specialist applications, such as for training in surgical techniques and learning how to operate manufacturing equipment, consumer usage to date has been primarily limited to gaming.   

What’s preventing AR/VR devices from reaching the popularity of other wearables for consumers? 

A variety of hurdles exist, from neck and eye strain to the user experience itself, but many share a common thread: comfort. The AR/VR devices of the future must be designed for comfort first — a challenge when considering an untethered VR headset may contain a display, optical system, growing variety of sensors, haptic devices, external cameras, audio and voice systems, wireless connectivity, batteries, required processing power to render a virtual environment, and the cooling system necessary to prevent that processor from overheating. And this only takes into account what’s inside the headset. Externally, there’s the housing itself that must be durable enough to withstand wear and light enough to be worn for an extended period. 

There isn’t a one-size-fits-all solution to these hurdles, but many are addressed through the miniaturization of the electronic components within the devices — specifically as they pertain to connectivity. After all, smaller components can mean lighter components and a lighter headset is one way to improve comfort. But it’s about more than just reducing weight — it’s about improving functionality at the same time. 

Here are three ways beyond weight reduction that miniaturized connectivity solutions will jumpstart AR/VR device adoption through a new era of comfort and capability. And each represents a multitude of design challenges — many of which are surprisingly unexpected.

For many, a VR device is only as good as the level of immersion it can provide to a user and that is driven by the quality of the displays within the device. Shrinking OLED or microLED displays to the size of a postage stamp, while delivering refresh rates of at least 90 Hz and resolutions exceeding 4K, introduces a host of challenges. 

• The growing electronic density increases risks of electromagnetic interference (EMI). 
  
• Signal integrity and noise can become more problematic as resolution grows. 
• Higher resolution displays produce an increasing level of heat and can be more susceptible to voltage drops. 
• These displays often require greater amounts of power.

Miniaturized connectors provide more than just space savings — they incorporate EMI shielding, innovative pin layouts, thermal mitigation features and even features to ease assembly. Miniaturization is also reducing the impact displays have on battery performance. A team from the University of Waterloo has developed more energy-efficient displays that incorporate solid-state lighting designs and advanced electronic circuits to increase battery life by 30% while decreasing manufacturing costs. 

Additionally, miniaturized connectors enable innovative display functionality like foveated rendering which utilizes built-in eye-tracking systems to minimize processing power by only rendering high-quality images where eyes are focused. Foveated rendering can ease the burden on both the display and processor, but the more advanced foveated rendering technologies require making room for cameras or other means of optical sensors. 

The display is just one piece of a VR headset’s vision system — another is the optics. Although an optical lens may not appear to be directly impacted by a miniaturized connector, the influence on clarity and performance can be significant. 

In an optical system, space is paramount and heavily defined by the laws of physics. Lens size, shape, thickness and substrate determine how much and how well a wearer can see through a lens, contribute to the overall weight and footprint of a headset, and influence optical distortions. Chromatic aberrations, in which colors begin to blend and blur especially around the outside of an object, have been a particular problem that must be overcome within the designs of these vision systems.

Today’s headsets are beginning to migrate from bulky and aberration-prone Fresnel lenses to more streamlined pancake lenses. While pancake lenses provide many benefits over Fresnel — such as reduced  chromatic aberration and less reliance on software image correction — they absorb more light, emphasizing the need to make space in the headset  for brighter OLED and microLED displays.

Miniaturized connectors also make way for even more advanced optical systems that bridge the gap between electronics and optics, such as tunable liquid crystal lenses in which voltage is applied to adjust focal length. This can eliminate the need for larger, traditional optical designs and reduce how much a headset protrudes from the face. 

How else can miniaturized connectors improve optical systems?

• Optical lenses can be highly sensitive to temperature change. Miniaturized connectors can improve thermal stability and minimize optical errors.
• Optical systems must be specifically aligned to maintain visual clarity, but their performance can be unique to the user. The future of VR devices must accommodate the wearer’s own vision preferences and weaknesses. Miniaturized connectors can ease modularity, alignment and stability of optical systems by reducing mechanical stresses and improving plug-and-play functionality, allowing a user to swap out lenses. 

Today’s most powerful AR and VR systems require a cable connection to external computers that provide the processing power for more realistic graphics, lighting and overall visual immersion. Although this may not be problematic for desk-bound activities, being tethered is restrictive and prone to accidental disconnect; it also increases the risk of injury. 

The future of these devices is in untethered units that are fully self-contained — able to provide the high-resolution experience necessary to seamlessly transition from the real world to the virtual world. But this doesn’t just mean more capable CPUs, GPUs and even dedicated AI processing chips — a truly virtual experience requires additional sensors for:

• motion to detect movement and acceleration
• facial tracking to transpose expressions on avatars
• haptic feedback to mimic touch and resistance
• environmental detection for mixed reality experiences and  accidental injury avoidance
• biometric measurement to detect physiological responses 
• audio and voice detection for noise reduction and voice control
• position tracking to convey precise location in a virtual environment. 

Miniaturized connectors are necessary to make room for the abundance of sensors and processors while ensuring consistent power and immediate, reliable data transmission and providing the durability to use the device in conditions including frequent, sudden motion and vibration. As with the displays, this density of sensors and computing elements can increase EMI, impact signal integrity and amplify the risks of heat. The greater device complexity also puts more components at risk of damage caused by vibration, rapid acceleration and other effects of use. When creating an immersive experience, these factors can cause lag, physical discomfort due to eye strain and temperature, as well as overall disruption.  

Additionally, the future of VR may not just be in modular optical systems where lenses are replaceable, but entirely modular devices where processors or even sensors can be added and removed over time. Miniaturized connectors improve this modularity by reducing the risk of damage or error caused by complicated cabling interfering during the upgrade process. 

The future of AR and VR technology is dependent on comfortable and immersive consumer experiences. But comfort means more than just reducing weight and front heaviness — it also means negating eye strain, allowing freedom of movement and minimizing latency and other delays in input and feedback. 

That’s where Molex’s extensive engineering expertise and proven history in miniaturization comes in. Our broad portfolio of miniaturized interconnect solutions is designed to tackle the many challenges of AR and VR devices while ensuring durability and reliability. For example, our Quad-Row Board-to-Board Connectors achieve a 30% space savings with a staggered circuit layout, deliver up to 3.0A power and have been field-tested in the highest-selling smartwatch worldwide, with over 50 million shipped since 2020. And our fully EMI-shielded Flex-to-Board RF mmWave Connector 5G25 Series offers high-speed capability and robust mating in a reduced footprint, ideal for increasing functionality in space-constrained applications. 

Miniaturization is now a necessity for OEMs to meet consumer expectations for smaller, lighter, more capable and more comfortable devices. Our global multi-disciplinary team drives innovation through a collaborative approach with our customers, from the earliest stages of design to manufacturing and on-time delivery to meet consumer demand. 

Learn more about Molex’s miniaturization solutions here: https://www.molex.com/en-us/trends-insights/miniaturization.