32results about How to "Optical total length" patented technology

The utility model relates to a low total length 8M foresight optical lens, which is characterized in that an optical system of the lens is composed of a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens and a seventh lens which are sequentially arranged from left to right along a light incident light path. The lenses are made of plastic and glass materials, the first lens, the second lens, the fourth lens, the fifth lens and the sixth lens are glass spherical lenses, the third lens and the seventh lens are plastic aspheric lenses, and the fifth lens and the sixth lens form a balsaming lens group. By reasonably distributing the focal power and the surface type of each lens, the central thickness of each lens, the distance between the lenses on the optical axis and the like, the total length of the lens and the radial size of each lens are reduced while the requirements of a front-view wide-angle camera and a front-view narrow-angle camera are replaced by the low-total-length 8M ultra-wide-angle imaging performance of the lens; and the lens group is miniaturized.

The invention relates to a medium-focus large-aperture long-flange video lens with a focal length of 50mm. The medium-focus large-aperture long-flange video lens comprises a first lens group, an iris diaphragm and a second lens group which are sequentially arranged along a light incidence direction of a light path, wherein the first lens group serves as an immovable fixed group, the focal power is positive, and the first lens group is composed of lenses L11-L17 which are sequentially arranged in the light incidence direction of a light path and comprises two groups of doublet lenses and a group of triplet lenses; the second lens group serves as a movable focusing group, the focal power is positive, and the second lens group is composed of lenses L21-L27 which are sequentially arranged in the light incidence direction of the light path and comprises two groups of doublet lenses and a glass aspheric lens; the focal length value f1 of the first lens group and the focal length value f2 of the second lens group satisfy 0.47 lt; f2 / f1lt; and 0.56% of the total weight. The lens achieves a large clear aperture, high MTF resolution, small distortion and reduced achromatism, is short in total optical length, and meets a camera module matched with a long flange back focus.

The utility model relates to a high-brightness low-cost DMD welcome lamp lens. An optical system of the lens is composed of a first lens, a second lens, a third lens, a diaphragm, a fourth lens and a fifth lens which are sequentially arranged from left to right along a light incident light path. The lenses are made of plastic and glass materials, the first lens, the second lens, the third lens and the fourth lens are plastic aspheric lenses, and the fifth lens is a glass spherical lens. By reasonably distributing the focal power and the surface type of each lens, the central thickness of each lens, the axial distance between the lenses and the like, the imaging performance requirement of the lens is met, the total length of the lens and the radial size of each lens are reduced, and the miniaturization of the lens group is realized.

The utility model relates to a six-piece type side rear-view camera. An optical system of the camera is composed of a first lens, a second lens, a diaphragm, a third lens, a fourth lens, a fifth lens and a sixth lens which are sequentially arranged from left to right along a light incident light path. Under the condition that retroflexion caused by aspheric coefficients is not considered, the first lens is a meniscus concave negative lens, the second lens is a biconvex positive lens, the third lens is a biconvex positive lens, the fourth lens is a meniscus concave negative lens, the fifth lens is a biconvex positive lens, the sixth lens is a plano-concave negative lens, and all the lenses are made of glass materials. Wherein the first lens is a glass aspheric lens, and the third lens and the fourth lens form a balsaming lens group. While 3M clear imaging is realized, the number of sheets is relatively small and the appearance size is relatively small.

The utility model relates to a DMD welcome lamp lens with short total length, the lens is composed of a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens and a seventh lens from left to right along a light incident light path, the lenses are made of glass materials, the first lens, the third lens, the fourth lens, the fifth lens, the sixth lens and the seventh lens are glass spherical lenses, the second lens is a glass aspheric lens, wherein the third lens and the fourth lens, and the fifth lens and the sixth lens form a balsaming lens group. By reasonably distributing the focal power and the surface type of each lens, the central thickness of each lens, the axial distance between the lenses and the like, the imaging performance requirement of the lens is met, the total length of the lens and the radial size of each lens are reduced, and a 33 mm lens group is formed.

The utility model relates to a large-aperture six-piece type side rear-view camera, and the optical system of the camera comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are provided with focal power along an incident light path, and a diaphragm is arranged between the second lens and the third lens. Wherein the third lens and the fourth lens are closely connected to form a balsaming lens group; the first lens is a biconcave negative lens, the second lens is a biconvex positive lens, the third lens is a biconvex positive lens, the fourth lens is a biconcave negative lens, the fifth lens is a biconvex positive lens, and the sixth lens is a meniscus concave negative lens. The first lens, the second lens, the third lens and the fourth lens are glass spherical lenses, and the fifth lens and the sixth lens are glass aspheric lenses. The imaging angle of an object is larger than 80 degrees, and meanwhile, the camera has the advantages that the imaging definition is 3M, the F number is 1.4, the tolerance sensitivity is low, the high-low temperature stability is good and the like, and scenes behind the side of a vehicle and far away from the vehicle can be monitored more comprehensively.

The invention discloses an optical lens and electronic equipment. The optical lens sequentially comprises a first lens to a sixth lens from a first side to a second side along an optical axis. Wherein the focal power of the first lens is negative, and the focal power of the third lens is positive. The second side surface of the first lens is a concave surface; the first side surface of the second lens is a concave surface, and the second side surface is a convex surface; the first side surface of the third lens is a convex surface; the second side surface of the sixth lens is a concave surface. The fourth lens and the fifth lens are glued to form a glued lens; the positive and negative attributes of the symbols of the focal power of the fourth lens and the fifth lens are opposite. The optical lens satisfies 1.5 < = TTL / F < = 2.8, 0.25 < = F3 / F < = 1.7, d56 / TTL < = 0.025, 0.225 < = (d8 + d9) / TTL < = 0.4, and R5 / R6 < = 2.

An optical lens, a camera module and a terminal device are provided, the optical lens has six lenses with refractive power, the six lenses comprise a first lens to a sixth lens in sequence from an object side to an image side along an optical axis, the refractive power of the first lens is negative, negative, positive, negative, positive and negative, and the object side surface and the image side surface of the first lens are a convex surface and a concave surface near the optical axis respectively; the object-side surface and the image-side surface of the second lens element are respectively a concave surface and a convex surface near the optical axis; the object side surface and the image side surface of the third lens are convex surfaces near the optical axis; the fourth lens element has a convex object-side surface and a concave image-side surface in paraxial regions, respectively; the fifth lens element has an object-side surface and an image-side surface being convex in a paraxial region. The sixth lens element has a concave image-side surface in a paraxial region. The seventh lens element has a convex object-side surface and a concave image-side surface in paraxial regions, respectively. The optical lens satisfies the following relational expressions: 65 degree lt; a FOVlt; the angle is 75 degrees, and the tilt is 3.5 degrees; tTL / Hlt; 4.2. The optical lens provided by the invention can realize miniaturization and has the characteristic of a large field angle.

The utility model relates to a low total length 8M foresight main camera. An optical system of the main camera is composed of a first lens, a second lens, a third lens, a fourth lens, a diaphragm, a fifth lens, a sixth lens and a seventh lens which are sequentially arranged from left to right along a light incident light path. The lenses are made of plastic and glass materials, the first lens, the second lens, the fourth lens, the sixth lens and the seventh lens are glass spherical lenses, the third lens and the fifth lens are plastic aspheric lenses, and the sixth lens and the seventh lens form a balsaming lens group. By reasonably distributing the focal power and the surface type of each lens, the central thickness of each lens, the axial distance between the lenses and the like, the total length of the lens and the radial size of each lens are reduced while the requirements of a front-view wide-angle camera and a front-view narrow-angle camera are replaced by the low-total-length 8M ultra-wide-angle imaging performance of the lens, and the miniaturization of the lens group is realized.

The embodiment of the invention relates to the technical field of optics, and discloses a camera shooting optical lens which is composed of a first prism, a first lens group and a second lens group. The first lens group comprises a first lens and a second lens; the second lens group comprises a third lens, a fourth lens and a fifth lens; the first lens group can be moved and adjusted: 4.00 < = fA / IH < = 4.80; 0.10 < = Rp1 / Rp2 < = 1.00; 0.20 < = d5 / d7 < = 1.20. The five-piece lens is divided into the first lens group and the second lens group, and the first lens group moves for focusing, so that the focusing mode of internal focusing of the optical lens is realized; the ratio of the focal length to the image height of the optical lens in the first state is set, and the optical lens has a relatively long focal length under the condition that the image height is fixed, so that the magnification of the optical lens can be improved; due to the concave-convex shape of the first prism, the deflection degree of light passing through the lens can be relieved; the thickness of the third lens and the thickness of the fourth lens are reasonably distributed, so that the optical total length of the optical lens can be compressed.

The embodiment of the invention provides an optical module and intelligent head-mounted equipment. The optical module comprises a display screen, a first lens and a second lens which are arranged along the same optical axis; wherein the first lens is located between the display screen and the second lens, the first lens is a plano-concave lens, and the plane of the first lens is glued with the display screen; a light splitting element is arranged on the surface, away from the display screen, of the first lens, a phase retarder and a polarization reflection element are arranged on the surface, close to the display screen, of the second lens in a stacked mode, and the phase retarder is located between the light splitting element and the polarization reflection element.

The utility model discloses a far infrared optical system and a far infrared optical lens, and the far infrared optical system sequentially comprises a first aspheric lens, a super lens and a second aspheric lens from the object side to the image side along the optical axis, the first aspheric lens is a negative lens, and the super lens is a positive lens. The surface, close to the object side, of the first aspheric lens and the surface, close to the image side, of the first aspheric lens protrude towards the object side. The focal power of the super lens is positive, the second aspheric lens is a positive lens, and the surface, close to the object side, of the second aspheric lens and the surface, close to the image side, of the second aspheric lens both protrude towards the image side. The super lens comprises a substrate and micro-nano structures, the micro-nano structures are arranged on the two sides of the substrate respectively, the positive and negative of the focal power of the front surface of the super lens are opposite to the positive and negative of the focal power of the rear surface of the super lens, and the super lens can eliminate certain chromatic aberration of the super lens. Through the combination of the first aspheric lens, the super lens and the second aspheric lens, the far infrared optical system is enabled to reduce the system size and the production cost to a certain extent on the premise of ensuring the imaging quality.

This application discloses a visible light optical system and a visible light optical lens. The visible light optical system includes a superlens, a first aspherical lens, a second aspherical lens, a third aspherical lens, and a fourth aspherical lens. The first, second, third, and fourth aspherical lenses are arranged sequentially along the optical axis from the object side to the image side. The superlens has a positive optical power. The first aspherical lens has a positive optical power, and both its object-side and image-side surfaces are convex towards the object side. The second aspherical lens has a negative optical power, and both its object-side and image-side surfaces are convex towards the image side. The third aspherical lens has a positive optical power, and both its object-side and image-side surfaces are convex towards the image side. The fourth aspherical lens has a negative optical power. The visible light optical system combines a superlens with a traditional refractive lens, giving it advantages such as low cost, small size, and excellent imaging quality.

The invention relates to a small telephoto lens for portable code scanning equipment and a working method of the small telephoto lens. The small telephoto lens is composed of a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens which are sequentially arranged in the light incidence direction, and a diaphragm is arranged between the third lens and the fourth lens. The second lens and the third lens are glued to form a balsaming lens group A, and the fourth lens and the fifth lens are glued to form a balsaming lens group B. According to the invention, the design of six glass spherical lenses is adopted, and the parameters and the on-axis distance of each lens are optimized, so that the optical performance of high resolution and long focal length can be satisfied, and meanwhile, the optical system has the advantages of low distortion and high illumination; and the total length of the lens is smaller, so that the miniaturization requirement of portable code scanning equipment is met.

The invention discloses an optical lens, which consists of seven lenses, and sequentially comprises a first group with positive focal power, a diaphragm and a second group with positive focal power from an object side to an imaging surface along an optical axis, the first lens has negative focal power, the object side surface is a convex surface, and the image side surface is a concave surface; the second lens has negative focal power, the object side surface of the second lens is a concave surface, and the image side surface of the second lens is a concave surface; the third lens has positive focal power, the object side surface of the third lens is a convex surface, and the image side surface of the third lens is a convex surface; the fourth lens has positive focal power, the object side surface of the fourth lens is a convex surface, and the image side surface is a convex surface; the fifth lens has negative focal power, the object side surface of the fifth lens is a concave surface, and the image side surface of the fifth lens is a concave surface; the sixth lens has positive focal power, the object side surface of the sixth lens is a convex surface, and the image side surface of the sixth lens is a convex surface; the seventh lens has positive focal power, the object side surface of the seventh lens is a convex surface, and the image side surface of the seventh lens is a concave surface. The optical lens provided by the invention at least has the characteristics of ultra-wide angle, large aperture and miniaturization through reasonable matching of the seven glass-plastic mixed lenses.

The utility model provides an infrared camera device. The infrared camera device sequentially comprises a first surface, a first diffraction surface, a second diffraction surface, a second surface and an imaging chip from a first side to a second side, the first diffraction surface and the second diffraction surface have positive diopters, the focal lengths of the first diffraction surface and the second diffraction surface are different, and the first diffraction surface and the second diffraction surface are super surfaces. According to the utility model, the problem of poor imaging quality of an infrared camera device in the prior art is solved.

An optical lens, a camera module and a terminal device are provided, the optical lens has seven lenses with refractive power, the optical lens sequentially comprises a first lens to a seventh lens from an object side to an image side along an optical axis, the refractive power of the first lens is negative, negative, positive, positive, positive, negative and positive, and the object side surface and the image side surface of the first lens are respectively a convex surface and a concave surface near the optical axis; the object-side surface and the image-side surface of the second lens element are respectively a concave surface and a convex surface near the optical axis; the object-side surface and the image-side surface of the third lens element are respectively a convex surface and a concave surface near the optical axis; the fourth lens element has an object-side surface and an image-side surface being convex in a paraxial region. The fifth lens element has an object-side surface and an image-side surface being convex in a paraxial region. The sixth lens element has an object-side surface and an image-side surface being concave in a paraxial region. The seventh lens element has a convex object-side surface and a concave image-side surface in paraxial regions, respectively. The optical lens satisfies the following relational expressions: FOV is greater than or equal to 140 degrees and less than or equal to 150 degrees, 7.2 lt; tTL / Flt; and 7.6. The optical lens provided by the invention can realize miniaturization, has the characteristic of a large field angle, and improves the imaging quality of the optical lens.

This invention provides a lidar receiving lens and a lidar system incorporating the receiving lens, comprising a first lens to an Nth lens arranged sequentially from the object side to the image side, where N is 3, 4, or 5; the first lens is a lens with positive focal length, its convex surface facing the object surface, and its refractive index Nd > 1.8; all lenses are made of glass. The lidar receiving lens of this invention features lightweight design and a small overall size. The rational allocation of optical power satisfies the requirements for a large aperture, high pixel count, and small overall optical length of the receiving lens; the first lens uses a high refractive index material, which can effectively reduce the outer diameter of this imaging system.

Embodiments of the present application disclose an optical lens group, a camera module, and a terminal, relating to the field of optical imaging technologies. The optical lens group includes a first lens, a second lens, a third lens, a fourth lens, a fifth lens, and a sixth lens sequentially arranged along the optical axis from the object plane to the image plane. The optical lens group satisfies the following relationships: 1.0 < f123 / f < 1.7; f / EPD ≤ 2.0. Through a reasonably balanced lens configuration, on the one hand, the overall optical length of the optical system can be effectively shortened, which is beneficial to the miniaturization of the optical system and can improve the imaging quality of the optical system; on the other hand, the optical lens group has the characteristic of a large aperture, so that the light flux per unit time of the optical system can be increased, and the imaging effect of the optical system in a dark environment can be enhanced.

The utility model discloses an observing and aiming lens. The sighting lens sequentially comprises a first lens, a second lens, a third lens, a fourth lens and a fifth lens from an object side to an image side along an optical axis, the second lens has positive focal power; the third lens has negative focal power; the fourth lens has positive focal power; the object side surface of the fifth lens is a concave surface, and the image side surface of the fifth lens is a concave surface; the object side surface of the sixth lens is a convex surface, and the image side surface of the sixth lens is a convex surface; the object side surface of the seventh lens is a concave surface, and the image side surface of the seventh lens is a concave surface; the object side surface of the eighth lens is a concave surface, and the image side surface of the eighth lens is a convex surface; the distance TTL from the center of the object side surface of the first lens to the imaging surface of the observing and aiming lens on the optical axis and the effective focal length F of the observing and aiming lens meet the condition that TTL / F is larger than or equal to 0.85 and smaller than or equal to 1.00.

The invention discloses an optical lens, a camera module and a terminal device, the optical lens comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens, the first lens has negative refractive power, the second lens has refractive power, the third lens has positive refractive power, the fourth lens has positive refractive power, the fifth lens has refractive power, and the sixth lens has refractive power. The fifth lens has negative refractive power, the sixth lens has positive refractive power, and the optical lens satisfies the following relational expressions: 1.5 lt; a TTL / CTALlt; 2.2, TTL is the distance from the object side surface of the first lens to the imaging surface of the optical lens on the optical axis, and CTAL is the sum of the thicknesses of the first lens to the sixth lens on the optical axis. According to the optical lens provided by the invention, the light, thin and miniaturized design of the optical lens can be realized, and meanwhile, the optical lens has relatively high imaging quality.

The embodiment of the application provides an optical module and a smart head-mounted device; the optical module comprises a display screen, a first lens and a second lens arranged along the same optical axis; wherein the first lens is located between the display screen and the second lens, the first lens is a flat-concave lens, and the flat surface of the first lens is glued to the display screen; a light splitting element is arranged on the surface of the first lens away from the display screen, a phase retarder and a polarization reflection element are stacked on the surface of the second lens close to the display screen, and the phase retarder is located between the light splitting element and the polarization reflection element.

The utility model discloses an infrared optical system and an infrared optical lens. The infrared optical system sequentially comprises a first aspheric lens, a super lens and a second aspheric lens from an object side to an image side, the first aspheric lens is a positive lens, the surface, close to the image side, of the first aspheric lens protrudes towards the object side, the surface, away from the image side, of the first aspheric lens protrudes towards the object side, and the super lens is a positive lens; the surface, close to the object side and the surface, away from the object side, of the second aspheric lens protrude towards the image side or the object side. According to the infrared optical system provided by the invention, the number of used lenses is relatively small while the imaging quality requirement is met, and the production cost of the infrared optical system can be reduced. And meanwhile, the total optical length of the infrared optical system is relatively short, so that the light weight and miniaturization of the infrared optical system are realized.

The invention discloses an optical system, a camera module and electronic equipment, the optical system comprises seven lenses with refractive power, and the optical system sequentially comprises a first lens, a fourth lens and a sixth lens with positive refractive power, and a second lens, a third lens, a fifth lens and a seventh lens with negative refractive power from an object side to an image side along an optical axis; wherein the object side surface of the first lens, the object side surface of the second lens, the object side surface of the third lens, the image side surface of the fourth lens, the object side surface of the fifth lens, the object side surface of the sixth lens and the object side surface of the seventh lens are convex surfaces near the optical axis; the image side surface of the first lens, the image side surface of the second lens, the image side surface of the third lens, the image side surface of the fifth lens, the image side surface of the sixth lens and the image side surface of the seventh lens are concave surfaces at the positions close to the optical axis. The optical system can satisfy miniaturization, and has a good imaging effect and a variable aperture characteristic.

The invention relates to a long-focus large-aperture long-flange video lens with a focal length of 85mm. The long-focus large-aperture long-flange video lens comprises a first lens group, an iris diaphragm and a second lens group which are sequentially arranged along the light incidence direction of a light path, the first lens group serves as an immovable fixed group, the focal power is positive, and the first lens group is composed of lenses L11-L16 which are sequentially arranged in the light incidence direction of a light path and comprises a group of four-gluing lenses and a group of double-gluing lenses; the second lens group serves as a movable focusing group, the focal power is positive, the second lens group is composed of lenses L21-L27 and lenses L21-L28 which are sequentially arranged in the light incidence direction of the light path, and the second lens group comprises a group of four-gluing lenses and a group of double-gluing lenses; the focal length value f1 of the first lens group and the focal length value f2 of the second lens group satisfy 0.36 lt; f2 / f1lt; and 0.43. According to the lens, large aperture, high resolution, small distortion and low dispersion are realized, the total optical length is reduced, and a camera module matched with a relatively long flange back focus is satisfied.

The present invention discloses a machine vision lens with a large target surface and a large viewing angle, comprising a first lens group G1, a second lens group G2 and a third lens group G3 with positive optical power arranged in sequence from the object surface to the image surface. When focusing, the first lens group G1 and the third lens group G3 are fixed relative to the image surface, and the second lens group G2 moves along the optical axis. The lens can achieve high-quality imaging in a wide working distance range by reasonably controlling the focal length ratio, lens shape and optical power of each lens group, with small distortion and high resolution, and has a large target surface, a large viewing angle, and high pixel performance, and is easy to achieve small and light weight of the lens.

The embodiment of the utility model discloses a long-focus receiving lens and a laser radar, in the long-focus receiving lens provided by the embodiment of the invention, a first lens and a second lens have positive focal power and adopt convex-concave surface types, a third lens has positive focal power and adopts a biconvex surface type, a fourth lens has negative focal power and adopts a biconcave surface type, and a fifth lens has positive focal power and adopts a biconvex surface type. The fifth lens has negative focal power and adopts a concave-convex surface type, and the sixth lens has negative focal power and adopts a double-concave surface type. According to the technical scheme, the shapes of the mirror surfaces of the lenses of the telephoto receiving lens are reasonably matched, so that the lens has a shorter optical total length, the size of the receiving lens is effectively controlled, and the telephoto receiving lens can adapt to a larger image surface size through setting the shapes of the mirror surfaces of the lenses, so that the image quality of the telephoto receiving lens is improved. High resolution and low distortion are achieved, and the imaging effect is not affected by shortening the total optical length.

The optical lens comprises a first lens group, a second lens group and a third lens group which are sequentially arranged from an object plane to an image plane along an optical axis, and the first lens group comprises a first lens, a second lens and a third lens and is used for enlarging the light beam size of the object plane; the second lens group comprises at least one group of balsaming lenses, comprises a fourth lens, a fifth lens, a sixth lens, a seventh lens, an eighth lens, a ninth lens, a tenth lens, an eleventh lens and a twelfth lens, and is used for shaping the light beam; and the third lens group comprises a thirteenth lens, a fourteenth lens, a fifteenth lens, a sixteenth lens and a seventeenth lens and is used for focusing the light beams. According to the technical scheme, the number of the lens groups included in the optical lens and the number of the lenses included in each lens group are reasonably set, so that clear imaging within the wavelength range of 550-850 nm can be realized, and the total optical length range of the lens is relatively small. Moreover, the second lens group comprises at least one group of balsaming lenses, so that the imaging chromatic aberration can be reduced.

The optical lens module comprises a display image source for emitting circularly polarized light rays propagating along a first light propagation direction; a first lens having a convex or planar light entrance surface and a convex light exit surface, through which the circularly polarized light rays are propagated to the light entrance surface and the light exit surface of a second lens; the second lens has a convex light entrance surface and a convex light exit surface; the third lens has a concave light entrance surface and a planar light exit surface, and an optical composite film layer is arranged on the light exit surface of the third lens; based on the optical composite film layer, the polarization state of the circularly polarized light rays is adjusted to form first linearly polarized light propagating along a second propagation direction, the first linearly polarized light is converted into second circularly polarized light, and the second circularly polarized light is converted into second linearly polarized light to pass through the light exit surface of the third lens through folding of the light path, so as to ensure good imaging effect, reduce the total optical length, and reduce the volume and weight.

The utility model discloses a lens assembly, a capsule endoscope and a system thereof. The lens assembly is sequentially provided with a first lens, a second lens, a diaphragm, a third lens and a fourth lens at intervals from an object side to an image side, each lens in the lens assembly is an aspherical mirror and is provided with an object side face facing the object side and an image side face facing the image side. The first lens element with negative refractive power has an object-side surface being convex in a paraxial region thereof and an image-side surface being concave in a paraxial region thereof. The second lens element with positive refractive power has an object-side surface being convex in a paraxial region thereof and an image-side surface being convex in a paraxial region thereof. The third lens element with positive refractive power has an object-side surface being convex in a paraxial region thereof and an image-side surface being convex in a paraxial region thereof. The fourth lens element with positive refractive power has an object-side surface being convex in a paraxial region thereof and an image-side surface being convex in a paraxial region thereof, and the lens element provided by the present application has a large field angle.