Adjustable Sunglasses Measurement Tool
Frame width, bridge & temple length measurement system for eyewear fitting
Industry:
Role & Scope:
Tools & Methods:
Gallery:
CAD Development & Engineering Proof:
Key features:
• Synchronized left/right frame expansion
• Independently sliding lenses for bridge measurement
• Adjustable temple arms with stepless control
• Mechanical measurement pointers and scales
• Internal gear and slider transmission system
• Compact, eyewear-like form factor
• Fully parametric CAD for rapid iteration
The Challenge:
The client needed a way to accurately measure three critical eyewear dimensions — frame width, bridge width, and temple length — using a single physical device that could be worn like normal sunglasses.
The challenge was that these three measurements must move independently, while still feeling natural and intuitive for the user. Frame width had to expand symmetrically, the lenses had to slide independently to measure the bridge, and the temples needed their own length adjustment — all inside a compact, comfortable, and manufacturable product.
Additionally, the device had to be suitable for prototyping via 3D printing and later adapted for injection molding.
Key constraints:
• Very tight packaging space inside the frame
• Required tolerance of ~0.1 mm across moving parts
• All three measurements had to remain independent
• Must be comfortable to wear on the face
• Must be manufacturable and easy to assemble
• Needed to support both 3D printing and future injection molding
Outcome:
The final result was a fully functional adjustable sunglasses measurement system with three independent, mechanically synchronized adjustment mechanisms.
The device allowed users to:
• Adjust frame width symmetrically
• Slide lenses to determine bridge width
• Extend temples to measure arm length
All measurements were displayed directly on the device via mechanical pointer and scale systems. The client approved the concept, the mechanical solution, and the final CAD, and the project was completed with full manufacturing-ready drawings.
What this project demonstrates:
This project demonstrates advanced mechanical problem-solving, precision tolerance control, and the ability to integrate multiple motion systems into a compact consumer product.
It also highlights the ability to translate rough client ideas into a fully engineered, production-ready device through structured iteration, feedback, and parametric modeling.
Process & Key decisions:
The project began with concept sketches to validate how multiple movements could coexist in the same compact frame. After early feedback from the client, the lens and frame mechanisms were separated so that bridge width would not interfere with frame width.
A stepless ratchet-based system was selected for smooth, continuous adjustment instead of fixed detents, allowing precise sizing without jumps between preset values.
The entire product was built as a layered mechanical stack — with frame expansion, lens sliders, and temple mechanisms occupying different vertical planes — allowing compact packaging while avoiding mechanical interference.