An optical imaging lens includes a first lens element to a third lens element, and each lens element has an object-side surface and an image-side surface. A periphery region of the image-side surface of the first lens element is concave, a second lens element has negative refracting power, an optical axis region of the object-side surface of the third lens element is convex, and an optical axis region of the image-side surface of the third lens element is concave. Lens elements included by the optical imaging lens are only the three lens elements described above, and the optical imaging lens satisfies the relationships of TL/(Gavg+BFL)≤1.400 and 0.700≤V1/V2≤1.150.

An optical imaging lens includes a first lens element to a third lens element, and each lens element has an object-side surface and an image-side surface. A periphery region of the image-side surface of the first lens element is concave, a second lens element has negative refracting power, an optical axis region of the object-side surface of the third lens element is convex, and an optical axis region of the image-side surface of the third lens element is concave. Lens elements included by the optical imaging lens are only the three lens elements described above, and the optical imaging lens satisfies the relationships of TL/(Gavg+BFL)≤1.400 and 0.700≤V1/V2≤1.150.

An optical system includes a front lens unit with positive refractive power, an intermediate lens unit, and a rear lens unit in order from an object side to an image side. The intermediate lens unit moves to change an interval between the front lens unit and the intermediate lens unit and an interval between the intermediate lens unit and the rear lens unit in focusing from infinity to a close range. The focal length of the front lens unit and the effective diameter of a lens surface closest to the image side in the rear lens unit satisfy a predetermined inequality.

An optical system includes a front lens unit with positive refractive power, an intermediate lens unit, and a rear lens unit in order from an object side to an image side. The intermediate lens unit moves to change an interval between the front lens unit and the intermediate lens unit and an interval between the intermediate lens unit and the rear lens unit in focusing from infinity to a close range. The focal length of the front lens unit and the effective diameter of a lens surface closest to the image side in the rear lens unit satisfy a predetermined inequality.

A dual-aperture zoom camera comprising a Wide camera with a respective Wide lens and a Tele camera with a respective Tele lens, the Wide and Tele cameras mounted directly on a single printed circuit board, wherein the Wide and Tele lenses have respective effective focal lengths EFL.sub.W and EFL.sub.T and respective total track lengths TTL.sub.W and TTL.sub.T and wherein TTL.sub.W/EFL.sub.W>1.1 and TTL.sub.T/EFL.sub.T<1.0. Optionally, the dual-aperture zoom camera may further comprise an optical OIS controller configured to provide a compensation lens movement according to a user-defined zoom factor (ZF) and a camera tilt (CT) through LMV=CT*EFL.sub.ZF, where EFL.sub.ZF is a zoom-factor dependent effective focal length.

A dual-aperture zoom camera comprising a Wide camera with a respective Wide lens and a Tele camera with a respective Tele lens, the Wide and Tele cameras mounted directly on a single printed circuit board, wherein the Wide and Tele lenses have respective effective focal lengths EFL.sub.W and EFL.sub.T and respective total track lengths TTL.sub.W and TTL.sub.T and wherein TTL.sub.W/EFL.sub.W>1.1 and TTL.sub.T/EFL.sub.T<1.0. Optionally, the dual-aperture zoom camera may further comprise an optical OIS controller configured to provide a compensation lens movement according to a user-defined zoom factor (ZF) and a camera tilt (CT) through LMV=CT*EFL.sub.ZF, where EFL.sub.ZF is a zoom-factor dependent effective focal length.

Disclosed is an interchangeable conversion lens for underwater photography or cinematography able to change from macro to wide angle photographic perspectives and consists of a sequential assembly of optical lens elements. This conversion lens includes an objective lens, a relay lens and a focusing unit which are positioned on an optical axis and are interrelated in their optical performance to one another. The objective lens is to form an intermediate image (reversed and inverted) from wide angle perspective to half the size of the sensor in the camera, this intermediate image is then transmitted through the relay lens and the focusing unit which projects the image through a macro lens into the sensor of a camera. The three parts can be disassembled and reassembled underwater, all three separate parts are waterproof and therefore the optical performance of water is taken into consideration in the optical system. The length of this lens can be extended or reduced, and the three individual parts can be changed according to personal preferences. This provides a flexible underwater optical system that can easily be changed in water between macro and wide angle perspectives, depending on the photographer's needs.

An optical imaging lens assembly, which is applied for an endoscopic optical device, from an object side to an image side aligned in order includes a first lens element, a second lens element and a third lens element. The first lens element has negative refracting power, and further has a first convex object-side surface and a first image-side surface. The second lens element has positive refracting power, and further has a second convex object-side surface and a second concave image-side surface. The third lens element has positive refracting power, and further has a third convex image-side surface and a third object-side surface.

An optical lens assembly includes, in order from the object side to the image side: a stop, a first lens element, a second lens element, a third lens element, and an infrared bandpass filter. An entrance pupil diameter of the optical lens assembly is EPD, a half of a maximum field of view of the optical lens assembly is HFOV, and the following condition is satisfied: 0.59<EPD/tan(HFOV)<1.33.

An optical lens assembly includes, in order from the object side to the image side: a stop, a first lens element, a second lens element, a third lens element, and an infrared bandpass filter. An entrance pupil diameter of the optical lens assembly is EPD, a half of a maximum field of view of the optical lens assembly is HFOV, and the following condition is satisfied: 0.59<EPD/tan(HFOV)<1.33.