Pir sensor fresnel lens

When sourcing PIR Fresnel lenses, you must prioritize the Detection Angle (ranging from 30° to 360°) and the Detection Distance (typically 3m to 15m). Pay close attention to the Focal Length, as it must match your PIR sensor's specifications to ensure sensitivity. Additionally, verify the Optical Transmittance in the 7-14μm infrared range; high-quality HDPE materials should offer transmittance above 70% to minimize signal loss.

The design varies significantly based on use: Ceiling-mounted lenses require a 360° multi-zone pattern for wide coverage, while Wall-mounted security lenses often feature a 'curtain' or long-range narrow beam. For smart lighting, a compact, flat design is preferred for aesthetics, whereas industrial high-bay sensors require thick, multi-segment lenses to detect motion from heights of 10 meters or more.

Since these are plastic components used in electronics, they must comply with RoHS (Restriction of Hazardous Substances) and REACH standards to ensure they are free from toxic chemicals. If the end product is for the US market, ensure the material meets UL 94V-2 or higher flame retardancy ratings. For outdoor applications, verify UV resistance to prevent the lens from yellowing or becoming brittle over time.

Request a Light Distribution Curve report and a Zemax optical simulation from the supplier. Inspect the surface finish for burrs or bubbles, which can cause false triggers. For bulk orders, ensure the supplier uses high-precision injection molds with a tolerance of ±0.02mm to maintain consistent focal points across all units.

The primary risk is Optical Mismatch, where the lens does not align with the sensor's focal point, leading to 'blind spots.' Another risk is Material Substitution, where a supplier uses recycled PE instead of optical-grade HDPE, reducing detection range. To mitigate this, always request golden samples and use Third-Party Inspection services like those offered on Made-in-China.com to verify material purity before final payment.

Custom Fresnel lenses involve high Molding Costs (NRE). Negotiate a rebate program where the mold fee is refunded once cumulative orders reach a certain volume (e.g., 50,000 units). For standard models, aim for a tiered pricing structure; increasing your order from 1k to 10k units can often yield a 20-30% cost reduction due to the efficiency of continuous injection molding.

Fresnel lenses are prone to surface scratches and deformation. Ensure the supplier uses Anti-static (ESD) trays or individual PE bags, packed in double-walled corrugated boxes with desiccant packs to prevent moisture buildup during sea freight. For urgent R&D needs, use Air Express (DHL/FedEx), but for bulk production, FOB shipping is recommended to maintain better control over logistics costs and customs clearance.

Utilize the Secured Trading Service on Made-in-China.com to ensure your payment is only released to the supplier after you confirm receipt and quality. Always verify the supplier's Business License and ISO 9001 Certification to ensure they are a legitimate manufacturer rather than a small trading company with no quality control over the molding process.