Super wide-angle optical system
A super wide angle optical system, according to various embodiments of the present invention, comprises: a first lens group including a negative refractive power, and a second lens group including a positive refractive power, in order from an object side; and a device for limiting the size of an aperture or light flux between the first lens group and the second lens group, wherein the first lens group comprises, in order, from the object: a plurality of meniscus lenses which are convex towards the object; a meniscus lens which is concave towards the object next to the meniscus lenses, wherein a lens, which is closest to an image in the first lens group, comprises a positive lens, and wherein the second lens group comprises a cemented lens in which lenses respectively including positive and negative refractive powers are bonded in order from the object side, wherein a lens, which is closest to an image in the second lens group has a positive refractive power. In addition, the super wide-angle optical system may be configured in various manners according to embodiments.
1. A super wide-angle optical system comprising:
a first lens group including a negative refractive power; and
a second lens group including a positive refractive power, the first lens group and the second lens group arranged sequentially from an object side; and
a structure between the first lens group and the second lens group, configured to restrict a size of one of an aperture and a luminous flux,
wherein the first lens group includes a plurality of meniscus lenses convex toward an object, a meniscus lens concave toward the object side, next to the plurality of meniscus lenses arranged sequentially from the object side, and a lens closest to an image in the first lens group, the lens closest to the image in the first lens group being a positive lens,
wherein the second lens group includes a cemented lens of a lens including a positive refractive power and a lens including a negative refractive power bonded to each other, arranged sequentially from the object side, and a lens closest to the image in the second lens group, the lens closest to the image in the second lens group being a lens including a positive refractive power, and
wherein cemented lenses are absent in the first lens group.
2. The super wide-angle optical system of claim 1 , wherein a meniscus lens closest to the image among the plurality of meniscus lenses convex toward the object in the first lens group includes a non-spherical surface.
3. The super wide-angle optical system of claim 1 , wherein the lens closest to the image in the first lens group including a non-spherical surface.
4. The super wide-angle optical system of claim 1 , wherein the lens closest to the image in the second lens group including a non-spherical surface.
5. The super wide-angle optical system of claim 1 , wherein a field of view of the super wide-angle optical system satisfies the following condition,
190≤Wfov [Conditional formula]
wherein the Wfov of the Conditional formula represents a maximum field of view.
6. The super wide-angle optical system of claim 1 , wherein a field of view, an image height, and a focal length of the super wide-angle optical system satisfy the following condition,
y
2
sin
θ
2
≥
f
≥
y
2
tan
θ
2
[
Conditional
formula
]
wherein the θ of the Conditional formula represents a half field of view, the y of the Conditional formula represents the image height (a distance from a center of an image to an outermost periphery of the image), and the f of the Conditional formula represents the focal length.