The present invention relates to an objective for photographic applications, comprising, in a sequence from an object side end to an image side end, a first lens group having a positive refractivity with at least one lens, a second lens group having a negative refractivity with a single lens, a third lens group having a negative refractivity with a single lens and a fourth lens group having a positive refractivity with at least one lens, wherein the lenses of the second and third lens groups each have a concave surface which face one another and define an air lens, wherein f1 is the overall focal length of the lenses of the second and third lens groups and f2 is the focal length of the air lens, and wherein the relationship 5.0≤f1/f2≤9.0 is true.

The present invention relates to an objective for photographic applications, comprising, in a sequence from an object side end to an image side end, a first lens group having a positive refractivity with at least one lens, a second lens group having a negative refractivity with a single lens, a third lens group having a negative refractivity with a single lens and a fourth lens group having a positive refractivity with at least one lens, wherein the lenses of the second and third lens groups each have a concave surface which face one another and define an air lens, wherein f1 is the overall focal length of the lenses of the second and third lens groups and f2 is the focal length of the air lens, and wherein the relationship 5.0≤f1/f2≤9.0 is true.

An imaging engine including a telephoto lens for compact long range barcode readers is disclosed herein. An example imaging engine includes an imaging sensor and a telephoto lens assembly. The example telephoto lens assembly includes a first lens, disposed along an optical axis; a second lens, disposed along the optical axis to correct for pupil aberrations of the image projected after a fourth lens onto the imaging sensor; a third lens, disposed along the optical axis to correct for chromatic aberration of the image projected after the fourth lens onto the imaging sensor; and the fourth lens, disposed along the optical axis to correct for optical field curvature of the image projected after the fourth lens onto the imaging sensor.

A large incident angle of an off-axis principal ray is ensured while a stroke of a moving lens group is kept long, and a size is reduced while a focusing operation in magnification is easy.

A magnifying endoscope optical system provided with a negative single lens cemented to an image pickup device and a moving lens group, capable of switching at least between a normal observation state and a proximity magnifying state can be made by moving the moving lens groups; and the following conditional expression (1) is satisfied:

−65<fr/fw<−2  (1) where reference character fr denotes a focal distance of the negative lens cemented to the image pickup device, and reference character fw denotes a focal distance of the entire system in the normal observation state (wide angle end).

The present disclosure relates to the technical field of optical lens and discloses a camera optical lens satisfying following conditions: 0.50≤f12/f≤1.20; 1.50≤f4/f≤5.00; −10.00≤R2/R1≤−1.20; where f12 denotes a combined focal length of the first lens and the second lens, f denotes a focal length of the camera optical lens, f4 denotes a focal length of the fourth lens, R2 denotes a central curvature radius of an image-side surface of the first lens, and R1 denotes a central curvature radius of an object-side surface of the first lens. The camera optical lens in the present disclosure satisfies a design requirement of long focal length and ultra-thinness while having good optical functions.

The present disclosure relates to the technical field of optical lens and discloses a camera optical lens satisfying following conditions: 0.50≤f12/f≤1.20; 1.50≤f4/f≤5.00; −10.00≤R2/R1≤−1.20; where f12 denotes a combined focal length of the first lens and the second lens, f denotes a focal length of the camera optical lens, f4 denotes a focal length of the fourth lens, R2 denotes a central curvature radius of an image-side surface of the first lens, and R1 denotes a central curvature radius of an object-side surface of the first lens. The camera optical lens in the present disclosure satisfies a design requirement of long focal length and ultra-thinness while having good optical functions.

An optical system includes, in order from an object side to an image side, a first lens unit having negative refractive power, an aperture stop, and a second lens unit having positive refractive power. The first lens unit includes a first lens having negative refractive power disposed closest to an object. The first lens has a meniscus shape that is convex to the object side. A predetermined condition is satisfied.

An optical system includes, in order from an object side to an image side, a first lens unit having negative refractive power, an aperture stop, and a second lens unit having positive refractive power. The first lens unit includes a first lens having negative refractive power disposed closest to an object. The first lens has a meniscus shape that is convex to the object side. A predetermined condition is satisfied.

A folded telephoto lens system may include multiple lenses with refractive power and a light path folding element. Light entering the camera through lens(es) on a first path is refracted to the folding element, which changes direction of the light on to a second path with lens(es) that refract the light to form an image plane at a photosensor. At least one of the object side and image side surfaces of at least one of the lens elements may be aspheric. Total track length (TTL) of the lens system may be 14.0 mm or less. The lens system may be configured so that the telephoto ratio (TTL/f) is less than or equal to 1.0. Materials, radii of curvature, shapes, sizes, spacing, and aspheric coefficients of the optical elements may be selected to achieve quality optical performance and high image resolution in a small form factor camera.

A camera optical lens includes, from an object side to an image side, a first lens having a positive refractive power, a second lens having a negative refractive power, a third lens having a negative refractive power, and a fourth lens having a positive refractive power. 2.70≤v1/v4≤4.30, −1.20≤f2/f≤−0.50, −0.80≤f3/f≤−0.30, −10.00≤(R7+R8)/(R7−R8)≤−2.00, and 3.00≤d4/d5≤10.00. f denotes a focal length of the camera optical lens. f2 denotes a focal length of the second lens. f3 denotes a focal length of the third lens. v1 denotes an abbe number of the first lens. v4 denotes an abbe number of the fourth lens. R7 denotes a curvature radius of an object-side surface of the fourth lens. R8 denotes a curvature radius. d4 denotes an on-axis distance. d5 denotes an on-axis thickness of the third lens. The camera optical lens can achieve a good optical performance while being ultra-thin and having a long-focal-length.