IP67 and IPX7: specify the actual protection target
IP67 specifies both solid-ingress and water-ingress protection; IPX7 specifies the water part without assigning a solid-ingress digit. Confirm the applicable IEC 60529 procedure and acceptance criteria with the laboratory. Neither label alone establishes resistance to hot showers, detergents, seawater, sweat or repeated cleaning. Define those exposures separately.
Design the microphone, speaker and temple as a system
For a microphone, evaluate the exposed membrane area, adhesive inner diameter, port depth, MEMS distance and alignment. Check sensitivity, frequency response, noise and array consistency. A speaker outlet needs its own assessment of excursion, front volume, distortion and water recovery. Independently sealed temples may need separate pressure-equalization paths; do not assume one acoustic membrane vents the whole frame.
Validate bonding, hinges and audio after exposure
Specify a continuous sealing land and a compatible adhesive. Check assembly pressure, dwell time and tolerance before testing representative glasses. Include hinge cycling, frame flex, drops, thermal cycling and relevant sweat or cosmetic exposure, then repeat sealing and acoustic checks. Distinguish water retained outside the barrier from actual ingress and measure recovery under a defined drying method.
What we need to evaluate
- Port and temple section drawings; microphone and speaker models
- IP67 or IPX7 test target, exposure sequence and acceptance criteria
- Available active area, bond width, substrate and surface treatment
- Permitted acoustic change, cavity volume, assembly method and sample schedule
Engineering FAQ
Does a waterproof acoustic membrane guarantee IP67 smart glasses?
No. Housings, hinges, cable passages, adhesive edges and other interfaces can leak. The complete assembled glasses must be validated; a membrane data sheet cannot establish the device rating.
Should IP67 and IPX7 use different membranes?
Not automatically. Select from the actual water exposure, sound path, active area and assembly. IP67 additionally specifies solid-ingress protection; the code alone does not identify a membrane grade.
What if the glasses sound muffled after water exposure?
Retained surface water can temporarily change sound without a leak. Measure wet-state performance and recovery, inspect the ingress boundary and compare microphone and speaker paths separately.