Four-Surface Near-Infrared Wafer-Level Lens for Iris Recognition

The lens system is divided into two separate wafer-level lens assemblies, each with multiple optical surfaces. The first lens assembly includes a first lens element with a first convex surface and a first concave surface, while the second lens assembly includes a second lens element with a second concave surface and a second convex surface. This segmentation allows each lens to be optimized independently while achieving the overall optical performance required for iris recognition.

The patent transitions from conventional single-lens designs to a multi-element wafer-level lens system. By stacking multiple thin lens elements in sequence along the optical axis, the system achieves high resolution and appropriate field of view with fewer total surfaces compared to traditional precision molded glass lenses. The wafer-level manufacturing enables this dimensional reorganization of optical elements.

The patent employs wafer-level lens manufacturing technology, which produces lenses using semiconductor fabrication processes. This approach replaces expensive precision molded glass lenses with cheaper wafer-based optical elements that can be mass-produced. The wafer-level lenses achieve sufficient optical quality for iris recognition at a lower cost point, making biometric authentication viable for consumer electronics.

The patent optimizes specific optical parameters of the wafer-level lenses to achieve the required performance. The first lens element has a positive optical power with specific curvature radii (first convex surface radius R1, first concave surface radius R2), while the second lens element has a negative optical power with specific curvatures (second concave surface radius R3, second convex surface radius R4). These parameter optimizations enable the cheaper wafer-level lenses to meet the resolution and field of view requirements.