Imaging lens

An imaging lens, sequentially comprising from an object side to an image side along an optical axis:

• a prism, having a light incident surface, wherein the light incident surface comprises at least one phase delay structure, and the at least one phase delay structure is a circle and comprises a circle center and a plurality of microstructures;
• a first lens element, having a negative diopter;
• a second lens element, having a negative diopter;
• a third lens element, having a positive diopter;
• a fourth lens element, having a positive diopter;
• and
• a fifth lens element, having a negative diopter, wherein
• the circle center of the at least one phase delay structure is on the optical axis, and a spacing between two adjacent microstructures among the microstructures of the at least one phase delay structure in a radial direction of the circle is the same,
• the first lens element to the fifth lens element are aspheric lens elements, and the imaging lens satisfies a conditional expression 3.86<TL/ImgH<9.8, where TL is a distance from an object side surface of the first lens element to an image plane on the optical axis, and ImgH is half of a diagonal of the image plane,
• the microstructures are a plurality of cylinders, and a diameter of a cylinder with a same radial distance from the circle center among the cylinders in the radial direction is the same, and
• wherein a distance between two adjacent cylinders among the cylinders in the radial direction of the circle falls within a range of 400 nm to 700 nm.

An imaging lens, sequentially comprising from an object side to an image side along an optical axis:

• a prism, having a light incident surface, wherein the light incident surface comprises at least one phase delay structure, and the at least one phase delay structure is a circle and comprises a circle center and a plurality of microstructures;
• a first lens element, having a negative diopter;
• a second lens element, having a negative diopter;
• a third lens element, having a positive diopter;
• a fourth lens element, having a positive diopter;
• and
• a fifth lens element, having a negative diopter, wherein
• the circle center of the at least one phase delay structure is on the optical axis, and a spacing between two adjacent microstructures among the microstructures of the at least one phase delay structure in a radial direction of the circle is the same,
• the first lens element to the fifth lens element are aspheric lens elements, and the imaging lens satisfies a conditional expression 3.86<TL/ImgH<9.8, where TL is a distance from an object side surface of the first lens element to an image plane on the optical axis, and ImgH is half of a diagonal of the image plane,
• the microstructures are a plurality of cylinders, and a diameter of a cylinder with a same radial distance from the circle center among the cylinders in the radial direction is the same, and
• wherein a distance between two adjacent cylinders with the same radial distance from the circle center among the cylinders falls within a range of 400 nm to 700 nm.