Abstract: An optical imaging lens sequentially includes a first lens element, a second lens element, a third lens element, and a fourth lens element along an optical axis from an object side to an image side. Each of the first lens element to the fourth lens element includes an object-side surface facing the object side and allowing imaging rays to pass through, and an image-side surface facing the image side and allowing the imaging rays to pass through. The first lens element has negative refracting power, and a periphery region of the object-side surface of the first lens element is convex. At least one of an optical axis region of the object-side surface of the second lens element and an optical axis region of the image-side surface of the second lens element is plane. The third lens element has negative refracting power or the fourth lens element has positive refracting power.

Abstract: An optical imaging lens, sequentially including a first, second, third, and fourth lens elements along an optical axis from an object side to an image side, is provided. Each of the first to fourth lens elements includes an object-side surface facing the object side and allowing imaging rays to pass through, and an image-side surface facing the image side and allowing the imaging rays to pass through. An optical axis region of the object-side surface of the first lens element is convex. The second lens element is a glass lens element. The third lens element has negative refracting power. An optical axis region of the image-side surface of the fourth lens element is convex. Lens elements of the optical imaging lens are only the four lens elements, and the optical imaging lens further satisfies following conditional expressions: HFOV/TTL?15.000 degrees/mm and 0.500?|RLGmin|/TG.

Abstract: An optical imaging lens system includes four lens elements arranged along an optical axis. The optical imaging lens system satisfies the relations 2.13°?HFOV/Fno?8.75°; 3.85?TTL/T1?7.00; and 0.8?AC34/T3, where a half field of view of the optical imaging lens system is defined as HFOV, an F number of the optical imaging lens system is defined as Fno, a distance measured from the object-side surface of the first lens element to an image plane along the optical axis is defined as TTL, a thickness of the first lens element along the optical axis is defined as T1, an air gap between the third and fourth lens elements along the optical axis is defined as AC34, a thickness of the third lens element along the optical axis is defined as T3.

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 ocular optical system satisfies: 40°??, where ? represents a half apparent field of view, which is one half the field of view of an observer.

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: An optical imaging lens, including a first lens element and a second lens element arranged in sequence from an object side to an image side along an optical axis. Each of the first lens element and the second lens element includes an object-side surface facing the object side and allowing imaging rays to pass through and an image-side surface facing the image side and allowing the imaging rays to pass through. An optical axis region of the image-side surface of the second lens element is concave, and a periphery region of the image-side surface of the second lens element is convex.

Abstract: Present embodiments provide for an optical imaging lens. The optical imaging lens includes at least a first lens element, a second lens element, a third lens element, a fourth lens element and a fifth lens element positioned in an order from an object side to an image side. Through forming a vignetting aperture and designing parameters satisfying at least two inequalities, the improved optical imaging lens may provide better optical characteristics, a decreased effective focal length and an enlarged angle of view while the total length of the optical imaging lens may be shortened.

Abstract: An optical imaging lens system includes four lens elements arranged along an optical axis. The optical imaging lens system satisfies the relations 2.13°?HFOV/Fno?8.75°; 3.85?TTL/T1?7.00; and 0.8?AC34/T3, where a half field of view of the optical imaging lens system is defined as HFOV, an F number of the optical imaging lens system is defined as Fno, a distance measured from the object-side surface of the first lens element to an image plane along the optical axis is defined as TTL, a thickness of the first lens element along the optical axis is defined as T1, an air gap between the third and fourth lens elements along the optical axis is defined as AC34, a thickness of the third lens element along the optical axis is defined as T3.

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 optical imaging lens includes a first lens element, a second lens element, a third lens element, and a fourth lens element from an object side to an image side in order along an optical axis. The first lens element to the fourth lens element each include an object-side surface facing the object side and allowing imaging rays to pass through and an image-side surface facing the image side and allowing the imaging rays to pass through. The object-side surface of the second lens element has a concave portion in a vicinity of the optical axis. The image-side surface of the second lens element has a convex portion in a vicinity of a periphery of the second lens element. The object-side surface of the third lens element has a concave portion in a vicinity of a periphery of the third lens element. The fourth lens element has negative refracting 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. 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: An optical lens assembly includes a plurality of lens elements, a filter, and a plurality of layer stacks. The lens elements are arranged in sequence from an object side to an image side along an optical of the optical lens assembly. Each of the lens elements includes an object-side surface and an image-side surface. At least one of the lens elements has a material capable of absorbing visible light. The filter is disposed between the lens elements and the image side and has transmittance less than 1% for light having a wavelength band greater than 1050 nm. The layer stacks are respectively stacked on the object-side surfaces and the image-side surfaces of the lens elements, so that transmittance of the optical lens assembly is greater than 95% for light having a wavelength band from 800 nm to 1000 nm.

Abstract: An optical lens set includes a first lens element of an object-side surface with a convex portion in a vicinity of an optical axis, a second lens element of an image-side surface with a concave portion in a vicinity of its periphery and a sixth lens element of an image-side surface with a convex portion in a vicinity of its periphery. T5min is the minimal distance from the object-side surface of the fifth lens element to the image-side surface of the fifth lens element and the fifth lens element has a fifth lens element thickness T5 along the optical axis to satisfy T5min/T5?0.6.

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 optical imaging lens includes first, second, third, fourth, fifth and sixth lens elements arranged in sequence from an object side to an image side along an optical axis. The third lens element is a first lens having a refracting power and sequentially counted from an aperture stop toward the object side. The fourth lens element is a first lens sequentially counted having a refracting power and from the aperture stop toward the image side. At least one of the third lens element and the fourth lens element has a positive refracting power and is a glass material. The optical imaging lens is complied with: 2.4?(G1+G2)/T6.

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 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.

Abstract: An optical imaging system includes, in the given 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 optical imaging lens includes a first lens of negative refractive power, a second lens of negative refractive power and of an image-side surface with a concave portion in a vicinity of its optical-axis, at least one of an object-side surface and of an image-side surface of a third lens being an aspherical surface and a fourth lens of an object-side surface with a concave portion in a vicinity of its optical-axis. An aperture stop is disposed between the first lens element and the third lens element. The Abbe number ?1 of the first lens element and the Abbe number ?4 of the fourth lens element satisfy 45??1?65 or 18??4?35.

Abstract: An ocular optical system includes a first lens element, a second lens element and a third lens element from an eye-side to a 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 eye-side surface of the first lens element has a concave portion in a vicinity of the optical axis. The display-side surface of the third lens element has a concave portion in a vicinity of a periphery of the third lens element. The ocular optical system satisfies 1?TTL/ER?10, wherein TTL is a distance from the eye-side surface of the first lens element to the display screen along the optical axis, and ER is a distance from a pupil of the observer to the eye-side surface of the first lens element along the optical axis.