Patent ID: 8496338

Claim:
A lens module, comprising: a lens barrel comprising an object-side end and an image-side end opposite to the object-side end; a first lens received in the lens barrel, and adjacent to the object-side end; a second lens received in the lens barrel, and adjacent to the image-side end in relative to the first lens; and a spacer positioned between the first lens and the second lens, and comprising an object-side surface and an image-side surface, the object-side surface facing the first lens, the image-side surface facing the second lens; the spacer defining a through hole penetrating through the image-side surface and the object-side surface, the through hole comprising an inner sidewall; a chamfer positioned at the intersection of the object-side surface and the inner sidewall, an included angle α formed between the chamfer and an optical axis of the lens module, the included angle α satisfying the formulas: α = arc ⁢ ⁢ tan ⁢ I ⁢ ⁢ 2 - I ⁢ ⁢ 1 2 ⁢ ( X - Z ) ; and 0 < Z ≤ 0.01 wherein I1 is a diameter of the through hole on the image-side surface, I2 is a diameter of the through hole on the object-side surface, X is a thickness of the spacer measured in a direction that is substantially parallel to the optical axis of the lens module, and Z is a width of the inner sidewall measured in a direction that is substantially parallel to the optical axis of the lens module.