Patent ID: 11867877
Assignee: LARGAN PRECISION CO., LTD.
Field: Optics (Instruments)
Classification: CPC G  B | IPC G

Claim 0:
1. A lens module, comprising:
a barrel;
an optical lens assembly, disposed in the barrel; and
an annular light trapping component, disposed in the barrel, the barrel and the annular light trapping component being independent pieces, and the annular light trapping component comprising:
an inner surface surrounding a central axis of the annular light trapping component, and the inner surface defining a central aperture;
an outer surface opposite to the inner surface;
an object-side surface facing toward an object side of the annular light trapping component, the object-side surface being connected to the inner surface and the outer surface; and
an image-side surface facing toward an image side of the annular light trapping component, the image-side surface being connected to the inner surface and the outer surface, and the image-side surface being opposite to the object-side surface;

wherein the inner surface comprises at least one L-shaped annular groove, the annular light trapping component comprises a plurality of stripe and wedge-shaped structures disposed in the at least one L-shaped annular groove, the stripe and wedge-shaped structures are arranged along a circumferential direction of the annular light trapping component, a light trapping structure is formed between every pair of the stripe and wedge-shaped structures, and each of the stripe and wedge-shaped structures comprises a tapered portion;
wherein the at least one L-shaped annular groove comprises a first side and a second side connected to each other, the first side and the second side are located between the object-side surface and the image-side surface, the stripe and wedge-shaped structures are disposed on the second side, an end of the stripe and wedge-shaped structures is facing and connected to the first side, and a degree of inclination between the first side and the central axis is larger than a degree of inclination between the second side and the central axis;
wherein each of the stripe and wedge-shaped structures has a wedge-shaped cross section, and each of the stripe and wedge-shaped structures extends from the object side to the image side;
wherein an angle between the first side and the second side of the at least one L-shaped annular groove is θ, and the following condition is satisfied:

46 degrees<θ<136 degrees;

wherein a thickness of the annular light trapping component is t, a length of each of the stripe and wedge-shaped structures is d, and the following condition is satisfied:

0.05<d/t<0.50.