Smart glasses have moved from concept to a real product category. Meta's Ray-Ban line dominates shipments today, while Google, Rokid, Xiaomi, and a wave of Chinese AI-glasses startups push the next generation of camera-, display-, and assistant-equipped frames. The electronics problem they all share is brutal: route MIPI display and camera signals, microphones, touch, IMU, and power across a temple arm that folds at a hinge, inside a frame that cannot exceed roughly 1.8 grams per eye, with no room for board-to-board connectors.
A rigid FR-4 board plus flat cables and connectors does not fit and does not survive. The signal path has to bend at the hinge thousands of times over a five-year life, and every connector you add is weight, height, and a vibration failure point you cannot afford on a face-worn device. This is exactly the problem rigid-flex was built to solve: rigid islands carry the SoC, PMIC, and camera modules, while continuous copper crosses the hinge on a thin polyimide flex section — no connectors, no cable assembly, no connector-induced impedance discontinuities on the MIPI lanes.
We focus on the part of this market the large factories ignore: fast-turn prototypes and low-volume-high-mix production for AR/AI glasses teams that are still iterating mechanically. We are honest about where we fit — volume design-wins on flagship frames go to incumbent suppliers. Our entry point is the prototyping-through-pilot phase, with hinge bend-zone fatigue processing, ultra-thin lamination, and ENIG camera pads that match what those programs actually need.
Flex sections that cross the temple hinge are processed for 5+ year fatigue life: rolled annealed copper, neutral-axis stackup, cross-hatched ground, and staggered vias kept clear of the bend zone.
Standard 0.2mm flex sections with a 25µm ultra-thin core option for the tightest temple arms. Every micron counts inside a sub-2g/eye weight budget.
ENIG finish on camera and sensor pads delivers the flat, gold-protected surface fine-pitch image-sensor and MIPI modules require. Wire-bondable and solderable.
Prototype quantities from 5 pieces and pilot runs that big factories decline. Built for AI-glasses startups iterating mechanics and optics week over week.
Smart glasses impose constraints that rule out conventional construction.
The display, camera, and sensors live in the front frame; the battery, SoC, and PMIC live in the temple arms. The interconnect between them has to fold at the hinge every time the glasses are worn and stored. A rigid-flex board carries copper continuously across that hinge on a thin flex section — no connector, no cable.
Anything heavier than roughly 1.8 grams per eye becomes uncomfortable on the nose bridge within minutes. Eliminating board-to-board connectors and flat cables removes height, weight, and assembly stack-up that a connectorized design cannot.
Open-and-close cycles add up fast. A pair worn daily sees thousands of hinge flex events per year. The flex section must be designed for fatigue, not a single static fold.
Micro-OLED or LCoS displays, image sensors, microphones, touch, and IMU all need routing in a frame with zero spare millimeters. Rigid islands give those components a solid mounting surface; the flex sections route between them.
Smart-glasses rigid-flex sits at the high-density end of our capability.
Four layers suffice for simpler audio-and-sensor frames. Camera-and-display frames with MIPI-DSI/CSI typically need 6-8 layers to route the high-speed lanes plus power and control.
Fine geometry is required to fit MIPI lanes and fan-out under image-sensor and display connectors in the available area.
Rigid sections at ~1.0mm carry the components. The rigid-to-flex transition steps down to ~0.6mm, and the flex section runs at 0.2mm — or a 25µm ultra-thin polyimide core for the most weight- and space-constrained temples.
Stacked or staggered laser microvias enable the routing density needed under fine-pitch SoC and sensor packages. Microvias are kept out of the dynamic bend zone.
ENIG for the flat, oxidation-protected camera and sensor pads; controlled impedance held to ±5% on MIPI-DSI and CSI differential pairs so the display and camera links run clean across rigid and flex sections.
We believe in setting expectations honestly.
High-volume design-wins on shipping consumer glasses go to incumbent rigid-flex suppliers with the scale and qualification history those programs demand. We do not pretend otherwise.
Our sweet spot is the iteration phase: fast-turn prototypes, design-validation builds, and low-volume-high-mix pilot runs of a few hundred to a few thousand units. That is the gap the big factories ignore because the volumes are too small and the mix changes too often.
Chinese and global AI-glasses startups iterating mechanics, optics, and electronics need a fab that turns a rigid-flex revision in days, not a quarter, and accepts low-volume orders without punitive minimums. That is what we do.
As a design stabilizes and volume ramps, we support the transition — including helping you qualify a higher-volume source if the program outgrows our capacity. We would rather keep your prototyping business and refer the megavolume than over-promise.
6-layer rigid-flex routing MIPI-DSI from a temple-mounted driver to a micro-OLED in the front frame, crossing the hinge on a 0.2mm flex section with ±5% impedance control.
8-layer rigid-flex with ENIG camera pads, dual microphone routing, and any-layer microvia HDI under the SoC. Prototype build for a startup iterating frame geometry.
25µm ultra-thin polyimide core carrying power, IMU, and touch signals through a slim temple arm hinge, processed for 5+ year open/close fatigue life.
A smart-glasses interconnect must cross a folding hinge, fit a ~1.8g/eye weight budget, and survive 5+ years of bend cycles with no room for connectors. Rigid-flex carries copper continuously from the temple arm across the hinge into the front frame on a thin flex section — eliminating connector weight, height, vibration failure points, and the impedance discontinuities that connectors introduce on MIPI lanes.
We design the hinge bend zone for 5+ years of daily open/close service, which works out to thousands of flex events per year. We achieve this with rolled annealed copper, a neutral-axis stackup, cross-hatched ground planes instead of solid copper, staggered vias kept out of the bend zone, and bend radii sized to the flex thickness per IPC-2223.
Audio-and-sensor frames are usually fine at 4 layers. Once you add a micro-display and camera with MIPI-DSI/CSI links, 6-8 layers is typical to route the high-speed differential pairs plus power and control, using any-layer microvia HDI for fan-out under fine-pitch packages.
Fast-turn rigid-flex prototypes typically ship in 2-4 weeks, with quick-turn options in 5-7 business days at a premium. We support quantities from 5 pieces and low-volume-high-mix pilot runs, which is the gap high-volume factories decline. Send your stackup and we will quote the turn.
