Abstract: An optical imaging lens comprises first, second, third, fourth, fifth and sixth lens elements arranged sequentially from an object side to an image side along an optical axis. The object-side surface of the second lens element has a concave portion in the vicinity of a periphery of the second lens element, and the image-side surface of the second lens element has a concave portion in a vicinity of the optical axis. The image-side surface of the third lens element has a concave portion in the vicinity of a periphery of the third lens element. An effective focal length of the optical imaging lens is EFL, an air gap between the fourth lens element and the fifth lens element along the optical axis is G45, a central thickness of the sixth lens element along the optical axis is represented by T6, and EFL, G45 and T6 satisfy the equation: EFL/(G45+T6)?6.40.

Abstract: An imaging lens includes first to sixth lens elements arranged from an object side to an image side in order from an object side to an image side along an optical axis of the imaging lens. Through designs of surfaces of the lens elements and relevant optical parameters, a short system length of the imaging lens may be achieved while maintaining good optical performance.

Abstract: An imaging lens includes a first lens element, a second lens element, a third lens element, and a fourth lens element arranged from an object side to an image side in the given order. The image-side surface of the first lens element comprises a convex portion in a vicinity of a periphery of the first lens element. The imaging lens has a system length less than 3.0 mm. The imaging lens does not have any lens element with refractive power other than the first, second, third, and fourth lens elements.

Abstract: An optical imaging system includes, in a sequential order from the object side to the image side, a first lens element, a second lens element, a third lens element, and a fourth lens element arranged along an optical axis. The lens elements of the optical imaging systems may be made of the same material having absorption in visible wavelengths and high transmission in near infrared radiation. The lens elements may be coated with an antireflective coating that is optimized for near infrared radiation. The optical imaging system satisfies the relations 2.13°?HFOV/Fno?8.75°, and 0.56?G23/T1?1.54, where HFOV is the half field of view and Fno is the F number of the optical imaging system, G23 is an air gap between the second and third lens elements along the optical axis, and T1 is a thickness of the first lens element along the optical axis.

Abstract: An ocular optical system configured to allow imaging rays from a display frame to enter an observer's eye through the ocular optical system to form an image is provided. The ocular optical system includes a lens element having an eye-side surface and a display-side surface. The lens element has an optical axis extending from a display side toward an eye side. The display-side surface of the lens element adopts a Fresnel lens design. The ocular optical system satisfies: 4.317?EFL/T1?12.463, where EFL represents an effective focal length of the ocular optical system, and T1 represents a thickness of the lens element on the optical axis.

Abstract: An optical imaging lens comprises first, second, third, fourth, fifth and sixth lens elements arranged sequentially from an object side to an image side along an optical axis. Each of the lens elements has an object-side surface facing toward the object side and an image-side surface facing toward the image side. The object-side surface of the first lens element has a convex portion in the vicinity of the optical axis. The third lens element has positive refracting power. The object-side surface of the third lens element has a concave portion in the vicinity of the optical axis. The object-side surface of the fourth lens element has a concave portion in the vicinity of the optical axis. The object-side surface of the fifth lens element has a concave portion in the vicinity of its periphery.

Abstract: An optical imaging lens includes six lens elements disposed sequentially from an object side to an image side. The image-side surface of the first lens element includes a concave portion in a vicinity of an optical axis. The fifth lens element has negative refractive power and the image-side surface of the fifth lens element includes a convex portion in a vicinity of the optical axis. The image-side surface of the sixth lens element includes a concave portion in a vicinity of the optical axis. The optical imaging lens as a whole has only the six lens elements having refractive power.

Abstract: An optical imaging lens includes first, second, third, fourth and fifth lens elements arranged sequentially from an object side to an image side along an optical axis. The image-side surface of the first lens element comprises a concave portion in a vicinity of the optical axis. The object-side surface of the fourth lens element comprises a concave portion in a vicinity of the optical axis. The optical imaging lens as a whole has only the five lens elements having refractive power.

Abstract: Present embodiments provide for a mobile device and an optical imaging lens thereof. The optical imaging lens comprises five lens elements positioned sequentially from an object side to an image side. Through controlling the convex or concave shape of the surfaces, the refracting power of the lens elements and parameters to meet an inequality associated with the effective focal length, the optical imaging lens shows better optical characteristics and the total length of the optical imaging lens is shortened.

Abstract: An ocular optical system for imaging of imaging rays entering an eye of an observer via the ocular optical system from a display screen is provided. A side facing towards the eye is an eye-side, and a side facing towards the display screen is a display-side. The ocular optical system includes a first lens element, a second lens element, and a third lens element from the eye-side to the display-side in order along an optical axis. The first lens element, the second lens element, and the third lens element each include an eye-side surface and a display-side surface. Lens elements having refracting power of the ocular optical system are only the first lens element, the second lens element, and the third lens element.

Abstract: A Fresnel lens includes a Fresnel surface that includes effective Fresnel surfaces allowing imaging rays to pass through. Two adjacent effective Fresnel surfaces are connected through a non-effective Fresnel surface. On a cross-section including an optical axis of the Fresnel lens, a draft angle is between a reference line and a connecting straight line between one end of each non-effective Fresnel surface located at a tooth peak of the Fresnel lens and the other end of each non-effective Fresnel surface located at a tooth valley of the Fresnel lens. The optical axis coincides with the cross-section. The reference line is parallel to the optical axis and passes through the end of the effective Fresnel surface located at the tooth peak of the Fresnel lens. The draft angles each smaller than 90 degrees include first, second, third, fourth, and fifth draft angles which gradually increase radially outward from the optical axis.

Abstract: An imaging lens includes first to fifth lens elements arranged from an object side to an image side in the given order. Through designs of surfaces of the lens elements and relevant optical parameters, a short system length of the imaging lens may be achieved while maintaining good optical performance.

Abstract: An optical imaging lens including a first lens element, a second lens element, a third lens element, an aperture, a fourth lens element and a fifth lens element is provided. The first lens element is arranged to be a lens element of which refracting power being equal to 0 inverse millimeter (mm?1) in a first order from the object-side to the image-side. The second lens element is arranged to be a lens element having refracting power in a first order from the first lens element to the image-side. The third lens element is arranged to be a lens element having refracting power in a second order from the first lens element to the image-side. The fourth and fifth lens element are respectively arranged to be lens elements having refracting power in a first and a second order from the aperture to the image-side.

Abstract: An optical imaging lens includes six lens elements disposed sequentially from an object side to an image side. The image-side surface of the first lens element comprises a concave portion in a vicinity of an optical axis. The third lens element has positive refracting power. The fourth lens element has positive refracting power. The image-side surface of the fifth lens element comprises a convex portion in a vicinity of the optical axis. The optical imaging lens as a whole has only the six lens elements having refractive power.

Abstract: An optical imaging lens includes first, second, third, fourth and fifth lens elements arranged sequentially from an object side to an image side along an optical axis. The image-side surface of the first lens element comprises a convex portion in a vicinity of its periphery. The third lens element has negative power. The object-side surface of the fifth lens element comprises a concave portion in a vicinity of its periphery. The optical imaging lens as a whole has only the five lens elements having refractive power.

Abstract: An ocular optical system for imaging of imaging rays entering an eye of an observer via the ocular optical system from a display screen is provided. A side facing towards the eye is an eye-side, and a side facing towards the display screen is a display-side. The ocular optical system includes a first lens element, a second lens element, and a third lens element from the eye-side to the display-side in order along an optical axis. The first lens element, the second lens element, and the third lens element each include an eye-side surface and a display-side surface. The second lens element has positive refracting power, and the display-side surface of the second lens element has a concave portion in a vicinity of the optical axis.

Abstract: An imaging lens includes first, second, third, fourth, fifth and six lens elements arranged in order from an object side to an image side along an optical axis. Each lens element has an object-side surface and an image-side surface. The image-side surface of the second lens element has a concave portion in a vicinity of the optical axis. The third lens element has negative refractive power. The object-side surface of the third lens element has a concave portion in a vicinity of the optical axis. The object-side surface of the fifth lens element has a convex portion in a vicinity of a periphery. All lens elements of the imaging lens having the refractive power are only the first, second, third, fourth, fifth and six lens elements.

Abstract: An imaging lens includes first to fifth lens elements arranged from an object side to an image side in the given order. Through designs of surfaces of the lens elements and relevant optical parameters, a short system length of the imaging lens may be achieved while maintaining good optical performance.

Abstract: An ocular optical system configured to allow imaging rays from a display frame to enter an observer's eye through the ocular optical system to form an image is provided. The ocular optical system includes a lens element having an eye-side surface and a display-side surface. The lens element has an optical axis extending from a display side toward an eye side. The display-side surface of the lens element adopts a Fresnel lens design. The display-side has a plurality of effective sub-surfaces and a plurality of ineffective sub-surfaces. The effective sub-surfaces are configured to allow the image rays to form an image. Each ineffective sub-surface connects two adjacent effective sub-surfaces. The ocular optical system satisfies: 25.000°???52.000°, where ? represents a maximum tilting angle of the effective sub-surfaces relative to a reference plane perpendicular to the optical axis.

Abstract: An ocular optical system includes a first lens element of a display-side surface with a convex portion in a vicinity of its periphery, a second lens element of positive refractive power and an eye-side surface with a concave portion in a vicinity of its periphery, a third lens element of negative refractive power and an display-side surface with a concave portion in a vicinity of an optical-axis, or a fourth lens element of an display-side surface with a concave portion in a vicinity of the optical-axis.