B270 BK7 Glass Optical Plano Lenses for Consumer Electronics 

1. Material

• Core Substrate: Precision-cut optical-grade glass – B270® superwhite crown glass (cost-effective, high clarity) and BK7 borosilicate glass (superior homogeneity, low bubbles).

• Coatings: Optional AR (Anti-Reflective), IR cut, or hard coatings for enhanced performance.

2. Key Properties

• Surface Quality: λ/2 flatness tolerance, 60-40 scratch-dig standard (80-50 optional).

• Transmission: >91% (B270) and >92% (BK7) across 400–700nm visible spectrum.

• Thermal Stability: BK7: Low CTE (7.1 × 10⁻⁶/K); B270: Higher thermal expansion but lower cost.

• Durability: Mohs hardness 6–7 (scratch-resistant), chemical-resistant surfaces.

• Precision: Tight thickness (±0.02mm), diameter (±0.05mm), and parallelism (<5 arcmin) control.

3. Primary Function

• Light Transmission: Maximizes undistorted light passage for sensors/displays.

• Protective Barrier: Shields sensitive electronics from dust, moisture, and physical damage.

• Beam Splitting/Filtering: Acts as substrate for coated optics (e.g., dichroic filters).

• Optical Reference: Provides flat windows for interferometry or alignment.

4. Critical Applications

• Smartphones/Tablets:

  • Camera lens cover glass

  • Proximity/ambient light sensor windows

  • Fingerprint scanner covers

• Wearables:

  • AR/VR headset lenses

  • Smartwatch health sensors

• Imaging Devices:

  • Barcode scanner windows

  • DSLR/mirrorless filter mounts

• Home Electronics:

  • Smart speaker microphone covers

  • Motion detector optics

• Displays:

  • Touch panel overlays

  • OLED/LCD protective covers