Abstract: An imaging lens includes a first lens group having a positive refractive power, an aperture stop, and a second lens group having a positive refractive power, which are disposed in order from an object. The first lens group has a first lens component having a negative refractive power and a second lens component having a positive refractive power, which are disposed in order from the object, and conditions expressed by the expressions 0.12<f/f1<0.47 and 0.016<D12/f<0.079 are satisfied, when f1 is a focal length of the first lens group, f is a focal length of the imaging lens, and D12 is an air distance between the first lens component and the second lens component of the first lens group.

Abstract: Providing an optical system having excellent optical performance over entire focusing range from infinity to a close distance, a method for focusing the optical system, and an imaging apparatus equipped therewith. The optical system includes, in order from an object, a first lens group G1 having positive refractive power, and a second lens group G2 having positive refractive power. The second lens group G2 is movable along an optical axis for varying focusing. The first lens group G1 satisfies a given conditional expression.

Abstract: A first lens group having a positive refractive power, an aperture stop, and a second lens group having a positive refractive power are provided in order from an object side. The first lens group includes, in order from the object side, a first lens that is a negative meniscus lens having a convex surface directed toward the object side, a negative second lens whose surface on an image side has a concave shape, and a positive third lens whose surface on the image side has a convex shape directed toward the image side. The second lens group includes, in order from the object side, a positive fourth lens whose surface on the image side has a convex shape directed toward the image side, a negative fifth lens having a biconcave shape, and a positive sixth lens having a biconvex shape. The fifth lens and the sixth lens are cemented together.

Abstract: A lens assembly includes, in order from an object side toward an image side along an optical axis thereof, a first lens having positive refractive power, and a second lens. The lens assembly satisfies the following conditions: 0<|f1/f|<2 and 0<|f2/f|<7, wherein f is an effective focal length of the lens assembly, f1 is an effective focal length of the first lens, and f2 is an effective focal length of the second lens. The first lens has at least one spherical surface, thus effectively decreasing the production cost of the lens assembly.

Abstract: An optical lens, especially an optical lens for mobile phones or image sensors such as CCD (Charge Coupled Device) or CMOS (Complementary Metal Oxide Semiconductor) is formed by a two-piece lens featuring high performance, minimized total length and low cost.

Abstract: An optical system which corrects an intensity distribution of incident light to a flat intensity distribution includes: a first lens group which includes at least one lens and has a positive refracting power; a second lens group which includes at least one lens and has a negative refracting power, the second lens group being positioned behind the first lens group in a direction of the incident light; and a third lens group which includes at least one lens and has a positive refracting power, the third lens group being positioned behind the second lens group in the direction of the incident light. In the optical system, the incident light is collimated, and the intensity distribution of the incident light is corrected to the flat intensity distribution by spherical aberrations of the first lens group, the second lens group and the third lens group.

Abstract: An image taking lens LA comprises an aperture S1, a first lens L1 and a second lens L2 which are arranged in this order from an object side to an image side. The firs lens L1 has a positive power and a meniscus shape with a convex surface facing an object; and the second lens L2 has a positive power with a convex surface facing an image. The first lens L1 and the second lens L2 satisfy the following formulae (1) and (2): 0.30<R1/R2<0.65 ??(1) 0.30<d3/F<0.50 ??(2) This image taking lens formed of the two lenses is small in size and has a high optical performance, in which the entire image taking lens has a short focal length.

Abstract: A cemented lens comprises first, second and third optical elements respectively formed by different solid materials, the third and first optical elements being cemented to each other, and the first and the second optical elements being cemented to each other, wherein both an incident surface and an exit surface of the first and second optical elements are refracting surfaces, and the following conditional expressions are satisfied: |??gF1|>0.0272 |??gF2|>0.0272 ??gF1×??gF2<0 ?1×?<0 where ??gF1 and ??gF2 are respectively anomalous dispersion characteristics of the materials for the first and the second optical elements with respect to a g line and an F line, and ?1 and ?2 are respectively refracting powers of the first and second optical elements when both the incident surface and the exit surface of the first and the second optical element are surfaces in contact with air.

Abstract: A lens with a very high degree of barrel distortion at the image plane (or pincushion distortion in object space).

Abstract: It is to provide an imaging lens that has excellent optical performance while being compact and light. The imaging lens includes, in order from an object side to an image surface side, a diaphragm 2, a first lens 3 that is a meniscus lens having a positive power whose convex surface faces the object side, and a second lens 4 that is a meniscus lens having a positive power whose convex surface faces the image surface side, wherein a condition expressed by ?30.5?r3/d3??19 (where, r3: center radius curvature of the object side face of the second lens 4, and d3: center thickness of the second lens 4) is to be satisfied.

Abstract: An imaging lens is used for forming an image of an object on an image-taking surface of a solid state image sensor element and includes, in order from an object side to an image surface side, a diaphragm, a first lens which is a meniscus lens having a positive power whose convex surface faces the object side, and a second lens which is a meniscus lens having a positive power whose convex surface faces the image surface side, wherein a condition expressed by the following expression is to be satisfied: 1.45?(r3+r4)/(r3?r4)?3.4, where, r3: center radius curvature of the object side face of the second lens, and r4: center radius curvature of the image surface side face of the second lens.

Abstract: Providing a large aperture wide-angle lens having high optical performance with sufficiently suppressed spherical aberration and sagittal coma flare, and an imaging apparatus using the lens. The lens including, in order from an object, a first lens group having positive refractive power, and a second lens group having positive refractive power, the second lens group being movable for focusing and including a 21 lens component having positive refractive power, a 22 lens component having negative refractive power, a 23 lens component having positive refractive power, and a 24 lens component having positive refractive power, and given conditions being satisfied.

Abstract: A two-piece type optical imaging lens that includes a first lens element with positive refractive power, a second lens element with positive refractive power, an IR cut-off filter and an image sensor arranged along an optical axis in order from an object side. The first lens element and the second lens element are both meniscus aspherical molded glass lens while a convex surface of the first lens element is on the object side and a convex surface of the second lens is on the image side. The two-piece type optical imaging lens satisfies following conditions: 0.4f?d<0.9f, 0.

Abstract: An imaging lens including, in order from an object side towards an image surface side, a diaphragm, a first lens which is a meniscus lens having a positive power whose convex surface faces the object side, and a second lens which is a lens having a positive power whose convex surface faces the image surface side, wherein conditions expressed by each of following expressions (1)-(6) are to be satisfied; 1.25?L/fl?0.8, 0.55?f1/f2>0, 1.5?f1/fl?0.9, 1?d2/d1?0.2, 0.35?d1/fl?0.1, and 0.27?d3/fl?0.1 (where, L: entire length of the imaging lens, fl: focal distance of the entire imaging lens, f1: focal distance of the first lens, f2: focal distance of the second lens, d1: center thickness of the first lens, d2: space between the first lens and the second lens on the optical axis, and d3: center thickness of the second lens).

Abstract: A subminiature imaging optical system including: a first lens having overall positive refractive power, the first lens including a first lens part having a convex object-side surface, a second lens part having an object-side surface in contact with an image-side surface of the first lens part and a third lens part having an object-side surface in contact with an image-side surface of the second lens part; and a second lens having overall positive refractive power, the second lens including a fourth lens part having an object-side surface with a convex center and a concave peripheral portion, about an optical axis, a fifth lens part having an object-side surface in contact with an image-side surface of the fourth lens part and a sixth lens part having an object-side surface in contact with an image-side surface of the fifth lens part, wherein the second lens part has a stop provided on the object-side or image-side surface thereof.

Abstract: An imaging lens including, in order from an object side towards an image surface side, a diaphragm, a first lens which is a meniscus lens having a positive power whose convex surface faces the object side, and a second lens which is a lens having a positive power whose convex surface faces the image surface side, wherein conditions expressed by each of following expressions (1)-(6) are to be satisfied; 1.25?L/fl?0.8, 0.55?f1/f2>0, 1.5?f1/fl?0.9, 1?d2/d1?0.2, 0.35?d1/fl?0.1, and 0.27?d3/fl?0.1 (where, L: entire length of the imaging lens, fl: focal distance of the entire imaging lens, f1: focal distance of the first lens, f2: focal distance of the second lens, d1: center thickness of the first lens, d2: space between the first lens and the second lens on the optical axis, and d3: center thickness of the second lens).

Abstract: A projection lens for magnifying and projecting input light on a screen is disclosed. The projection lens in accordance with an embodiment of the present invention includes: a first lens having a positive refractive power; a second lens having a negative refractive power and receiving the light that has passed through the first lens; and a third lens combined with the second lens to form a lens group having a positive refractive power and receiving the light that has passed through the second lens and projecting the light on the screen separated by a predetermined length from the lens group.

Abstract: It is to provide an imaging lens and an imaging device including the imaging lens, in which the imaging lens has excellent optical performance while being compact and light. The imaging lens comprises, in order from an object side to an image surface side, a first lens that is a meniscus lens having a positive power whose convex surface faces the object side, a diaphragm, a second lens that is a meniscus lens having a positive power whose convex surface faces the image surface side, wherein conditions expressed by 20?(r3+r4)/(r3?r4)?35 and 0.5?f1/f1?1 (where, r3: center radius curvature of the object side face of the second lens, r4: center radius curvature of the image surface side face of the second lens, f1: focal distance of the first lens, and fl: focal distance of the entire lens system) are to be satisfied.

Abstract: An imaging lens unit comprising, in order from the object side, a first lens having a meniscus shape with its convex surface on the object side, an aperture stop and a second lens having a meniscus shape with its convex surface on the image side. A maximal value of a tangent angle within a range of a lens surface effective diameter of the surface on the object side of the first lens is 70 to 90 degrees. A maximal value of a tangent angle within a range of a lens surface effective diameter of the surface on the image side of the second lens is 70 to 90 degrees.

Abstract: An optical system which corrects an intensity distribution of incident light to a flat intensity distribution includes: a first lens group which includes at least one lens and has a positive refracting power; a second lens group which includes at least one lens and has a negative refracting power, the second lens group being positioned behind the first lens group in a direction of the incident light; and a third lens group which includes at least one lens and has a positive refracting power, the third lens group being positioned behind the second lens group in the direction of the incident light. In the optical system, the incident light is collimated, and the intensity distribution of the incident light is corrected to the flat intensity distribution by spherical aberrations of the first lens group, the second lens group and the third lens group.

Abstract: A subminiature imaging optical system including: a first lens having overall positive refractive power, the first lens including a first lens part having a convex object-side surface, a second lens part having an object-side surface in contact with an image-side surface of the first lens part and a third lens part having an object-side surface in contact with an image-side surface of the second lens part; and a second lens having overall positive refractive power, the second lens including a fourth lens part having an object-side surface with a convex center and a concave peripheral portion, about an optical axis, a fifth lens part having an object-side surface in contact with an image-side surface of the fourth lens part and a sixth lens part having an object-side surface in contact with an image-side surface of the fifth lens part, wherein the second lens part has a stop provided on the object-side or image-side surface thereof.

Abstract: A subminiature imaging optical system with two lenses is provided. The optical system includes an aperture stop. A first meniscus lens has a positive refractive power, and includes aspherical surfaces at both of object and image sides. The object side of the first meniscus lens is convex. A second meniscus lens has a positive refractive power, and includes aspherical surfaces at both of the object and image sides. The image side of the second meniscus lens is convex. In addition, the first lens has a gap from the second lens according to following relation 1: 0.1<D/TL<0.2relation 1, where D is the gap between the first and second lenses and TL is a distance from the aperture stop to an image plane. The invention ensures a high-definition subminiature imaging optical system improved in various aberrations and superior in MTF properties.

Abstract: An imaging lens including, in order from an object side towards an image surface side, a diaphragm, a first lens which is a meniscus lens having a positive power whose convex surface faces the object side, and a second lens which is a lens having a positive power whose convex surface faces the image surface side, wherein conditions expressed by each of following expressions (1)-(6) are to be satisfied; 1.25?L/fl?0.8, 1?f1/f2?0.2, 1.8?f1/fl?1, 0.5>d2/d1?0.2, 0.35?d1/fl?0.1, and 0.27?d3/fl?0.1 (where, L: entire length of the lens system, fl: focal distance of the entire lens system, f1: focal distance of the first lens, f2: focal distance of the second lens, d1: center thickness of the first lens, d2: space between the first lens and the second lens on the optical axis, and d3: center thickness of the second lens).

Abstract: A compact rear projection image display apparatus in which the projection distance in a projection optical system is substantially reduced and no reflection mirror is used, thereby eliminating a major cause of image trapezoidal distortion. The rear projection image display apparatus has a projection lens system which includes a first lens group with positive refractive power and a second lens group which further enlarges an image enlarged by the first lens group. The projection lens system enlarges and projects an image displayed on an image display device, on a transmission screen. No reflection mirror is provided between the second lens group and the transmission screen and the image enlarged by the second lens group is directly projected on the transmission screen.

Abstract: A first lens group having a positive refractive power, an aperture stop, and a second lens group having a positive refractive power are provided in order from an object side. The first lens group includes, in order from the object side, a first lens that is a negative meniscus lens having a convex surface directed toward the object side, a negative second lens whose surface on an image side has a concave shape, and a positive third lens whose surface on the image side has a convex shape directed toward the image side. The second lens group includes, in order from the object side, a positive fourth lens whose surface on the image side has a convex shape directed toward the image side, a negative fifth lens having a biconcave shape, and a positive sixth lens having a biconvex shape. The fifth lens and the sixth lens are cemented together.

Abstract: The invention relates to an arrangement for projecting an image, which is made of pixels, onto a projection surface, including at least one light source whose intensity can be altered and which emits a light beam, also including a deflection device which deflects the light beam onto the projection surface, and a two-stage transformation lens system which is arranged between the deflection device and the projection surface. The invention also relates to optical systems for adjusting the angle of an incident light beam by means of a two-stage transformation lens.

Abstract: An optical pickup includes at least a laser light source emitting a laser beam, a collimator lens system including a plurality of lenses for collimating the light beam emitted from the laser light source and incident thereupon as diffused light, and an objective lens. The laser beam transmitted through the collimator lens system is incident upon the objective lens. The collimator lens system includes a first lens unit held so as to be movable in an optical axis direction of the laser beam and a fixed second lens unit.

Abstract: An LED light converging system includes an LED light source, and first and second lens units aligned in sequence along an optical axis. The LED light source provides source light. The first lens unit has a first focal length, and is disposed forwardly of and is spaced apart from the LED light source by a first distance less than the first focal length such that a virtual image of the source light provided by the LED light source is formed rearwardly of the LED light source. The second lens unit has a second focal length, is disposed forwardly of the first lens unit, and is spaced apart from the virtual image of the source light by a second distance larger than the second focal length such that a real image of the source light provided by the LED light source is formed forwardly of the second lens unit.

Abstract: A projection optical unit for enlarged projection of an image displayed by an image display element includes a first projection optical unit having positive refractive power, and a second projection optical unit having positive refractive power for further enlarging the first enlarged image obtained by the first projection optical unit. The first projection optical unit is in an almost telecentric relationship with respect to the image display element side and the first enlarged image side, and the first enlarged image is formed at the image display element side, rather than at the second projection optical unit.

Abstract: An imaging lens system includes a first lens having a meniscus profile with a convex surface facing an object side and having a positive refractive index; an aperture diaphragm; and a second lens having a meniscus profile with a convex surface facing an image side and having a positive refractive index, wherein the first lens, the aperture diaphragm, and the second lens are arranged in this order from the object side. The imaging lens satisfies conditional expressions where f represents a focal distance of a total lens system, f1 represents a focal distance of the first lens, and L represents a distance on the optical axis from the surface on the object side of the first lens to an image plane wherein calculation is done in terms of an air-equivalent thickness for a back insertion glass, and n(ave) represents an average value of refractive indexes at d-lines of the first and second lenses.

Abstract: An image pick-up lens system includes an aperture stop (10), a biconvex first lens (20), and a meniscus-shaped second lens (30) having a concave surface on a side of an object. The aperture stop, the first lens and the second lens are aligned in that order from the object side to an image side. Each of the lenses has at least one aspheric surface, and at least one of the lenses is made from an optical glass. The system satisfies the following condition: (1) 1<T/f<1.6, wherein f is a focal length of the system, and T is a length from the aperture stop to an image pick-up surface of the image side. The first condition (1) limits the total length of the system in order to provide compactness. The system also satisfies other conditions (2)–(6) as disclosed, in order to provide compactness, improved optical performance, and cost-effectiveness.

Abstract: The imaging lens system includes, from the object side, a diaphragm, a first lens as a positive meniscus lens whose convex surface faces the object side, and a second lens as a positive lens whose convex surface faces the image surface side, wherein the following expressions are to be satisfied 1.25?L/fl?0.8, 1?f1/f2>0.55, 1.8?f1/fl?1, 4?f2/fl?1.5, 1?d2/d1?0.5, 0.27?d1/fl?0.1, 0.27?d3/fl?0.1 (where, L: entire length of the lens system, fl: focal distance of entire lens system, f1: focal distance of the first lens, f2: focal distance of the second lens, d1: center thickness of the first lens, d2: distance between the first lens and second lens on the optical axis, d3: center thickness of the second lens).

Abstract: The imaging lens system includes, from the object side, a diaphragm, a first lens as a positive meniscus lens whose convex surface faces the object side, and a second lens as a positive lens whose convex surface faces the image surface side, wherein the following expressions are to be satisfied 1.25?L/fl?0.8, 0.55?f1/f2 s 0.2, 1.8?f1/fl?1, 4?f2/fl?1.5, 1?d2/d1?0.5, 0.27?d1/fl?0.1, 0.27?d3/fl?0.1 (where, L: entire length of the lens system, fl: focal distance of entire lens system, f1: focal distance of the first lens, f2: focal distance of the second lens, d1: center thickness of the first lens, d2: distance between the first lens and second lens on the optical axis, d3: center thickness of the second lens).

Abstract: A projection optical unit has two lens groups. A first projection optical unit disposed closest to an image display element, temporarily forms a first enlarged image (magnification: M1) at the image display element side, rather than at a second projection optical unit. The first enlarged image is subsequently projected in an enlarged form (magnification: M2, wherein M2>M1) onto a screen via the second projection optical unit. A field lens group having positive refractive power is disposed between the first projection optical unit and the second projection optical unit. Consequently, the relationship between F2, which is the F-value of the second projection optical unit, and F1, which is the F-value of the first projection optical unit, becomes F2=F1/M1, whereby it is possible to realize very-wide-angle imaging at a field angle exceeding 90 degrees.

Abstract: Provided is an image pickup lens, in which the optical characteristic can be improved and, further, the productivity can be improved through increasing the telecentricity by keeping the distance between the exit pupil and the sensor and effectively correcting the coma aberration and the distortion aberration. A first lens which is a meniscus lens having a positive power with its convex face facing an object side, a diaphragm, and a second lens which is a lens having a positive power with a strong convex face facing an image pickup surface side are provided in order from the object side. The first lens and the second lens are to satisfy the condition represented by following expressions: 4×f2?f1?f2??(1) 1.5×f1?f2?0.9×f1??(2) where, f1: focal length of the whole lens system f1: focal length of the first lens f2: focal length of the second lens.

Abstract: The present invention relates to an imaging lens with an number in the range 4.0, configured from two lenses, with a short lens optical length, and with sufficiently high image contrast so that sharp images are obtained. The imaging lens is configured by positioning, order from an object side to an image side, an aperture diaphragm, diaphragm, and a second lens, satisfying the following first lens, a second conditions. The first lens and second lens are both meniscus-shaped with convex surface facing the positive refractive power.

Abstract: A single focus lens includes, in order from the object side: a diaphragm stop; and first and second lens components, each lens component being of positive refractive power and each having a convex surface on the object side at least near the optical axis. Each of the two lens components has two aspheric surfaces, may be a lens element, and preferably is made of plastic. The single focus lens may include no other lens elements and the diaphragm stop may be on the object side of the single focus lens. Specified on-axis conditions are satisfied in order to reduce aberrations and to make the single focus lens compact. Additionally, satisfying a condition related to the aspheric shapes of the lens components helps reduce aberrations.

Abstract: A single focus lens includes, in order from the object side: a diaphragm stop; and first and second lens components, each lens component being of positive refractive power and each having a convex surface on the object side near the optical axis. Each of the two lens components has two aspheric surfaces, may be a lens element, and preferably is made of plastic. The single focus lens may include no other lens elements and the diaphragm stop may be on the object side of the single focus lens. Specified on-axis conditions are satisfied in order to reduce aberrations and to make the single focus lens compact. Additionally, satisfying a condition related to the optical distortion at the maximum image height and at fifty percent of the maximum image height helps reduce the actual observed distortion of an image.

Abstract: The invention provides a liquid-immersion objective optical system including a first lens group and a second lens group. The first lens group includes a first lens component having positive refractive power, an object side thereof being a flat surface and a convex surface thereof facing an image-plane side; a second lens component having positive refractive power, a convex surface thereof facing the image-plane side; a third lens component having positive refractive power as a whole, formed by cementing a biconvex positive lens and a negative lens; and a fourth lens component formed by cementing a negative lens and a biconvex positive lens. The second lens group includes a fifth lens component formed by cementing a lens having a concave surface facing the object side and a lens having a convex surface facing the image-plane side; a sixth lens component having positive refractive power; and a seventh lens component having negative refractive power.

Abstract: An optical lens is described. The optical lens comprises a barrel, a first lens and a second lens. The barrel has a light incident opening, and a receiving space, wherein the receiving space is successive to the light incident opening. Additionally, the first lens is disposed in the receiving space, and the first lens is partially exposed by the light incident opening, wherein the first lens has a first annular conical surface at the outer rim of the first lens. Further, the second lens is disposed in the receiving space, and embedded with the first lens. The second lens has a second annular conical surface on outer rim of the second lens, and the first annular conical surface is embedded with the second annular conical surface. Accordingly, the optical lens has better alignment accuracy and assembly performance.

Abstract: A photographic lens has a first and second positive lens. The first lens is a meniscus lens having a convex object side surface. The second lens is a double-convex lens. The photographic lens satisfies the following conditions: 5.6?f<8; F1>F2; 0.39<F/F1?0.5; 0.15<R1/F<0.19; 1.4<(F/R3)·f?3.0; and R3>|R4| wherein F is an overall focal length, F1 is a focal length of the first lens, F2 is a focal length of the second lens, f is a ratio of the overall focal length F to an effective aperture size defined by the first stop, R1 is a radius of curvature of the object side surface of the first lens, R3 and R4 are radii of curvature of the object side spherical surface and of an average spherical surface of the image side aspherical surface of the second lens.

Abstract: An imaging lens system includes a first lens 2 which is a meniscus lens with its convex face turned toward the object side and having a positive power, a diaphragm 3, and a second lens 4 which is a meniscus lens with its concave face turned toward the object side. The first lens 2, the diaphragm 3 and the second lens 4 are disposed sequentially in the named order from the side of the object toward an image surface. In the imaging lens system, the following conditional expressions are satisfied: 1.25×fl?L?0.8×fl; 1.26×fl?f1?0.85×fl; 0.8×d1?d2?0.35×d1; L?6.25 mm; d1?0.225×fl; and d3?0.225×fl, wherein L is a distance of the entire length of the lens system; fl is a focal length of the entire lens system; f1 is a focal length of the first lens; d1 is a thickness of the center of the first lens; d2 is a distance between the first and second lenses; and d3 is a thickness of the center of the second lens.

Abstract: An imaging lens device has an imaging lens system that forms an optical image and an image sensing device that converts the optical image formed by the imaging lens system into an electronic signal. The imaging lens system includes two lens elements each made of a homogeneous material and having a positive optical power, and fulfills the following condition: 1.25<L/f<2.00, where L is the distance from the most object side lens surface to the image plane, and f is the overall focal length of the lens system.

Abstract: An objective lens for recording and/or reproducing information of an optical information recording medium, comprises a first lens group having a positive refractive power and a second lens group having a positive refractive power. The first lens group and the second lens group are arranged in this order from a light source side. The objective lens is a finite conjugate type to converge a divergent light flux from a light source onto an information recording plane of the optical information recording medium and satisfies the following formula: NA?0.65 where NA is an image-side numerical aperture necessary for conducting recording and/or reproducing information of the optical information recording medium.

Abstract: A lens for image pickup is provided in which various aberrations are corrected satisfactorily, the optical length is at maximum approximately 6 mm, and moreover a sufficient back focus is secured. This lens for image pickup comprises a first lens, an aperture diaphragm, and a second lens, positioned in this order from the object side toward the image side. The first lens is a resin lens with a meniscus shape, with the convex surface facing the object side, and having positive refractive power. The second lens is a resin lens with a meniscus shape, with the convex surface facing the image side, and having positive refractive power.

Abstract: An imaging lens having a two-group, two-lens-element construction is disclosed that is formed of, in order from the object side without any intervening lens elements: an aperture stop; a first lens element of positive refractive power with its surface on the object side being aspherical and convex near the optical axis and its surface on the image side being aspherical and either convex or concave near the optical axis; and a second lens element of positive refractive power with its surface on the object side being aspherical and convex near the optical axis and its surface on the image side being aspherical and concave near the optical axis but convex toward the periphery. Specified conditions are satisfied in order to reduce various aberrations and provide a sufficient back focus for the insertion of other optical elements.

Abstract: An imaging lens of fixed focal length is formed of, in order from the object side, an aperture diaphragm, a first lens component having positive refractive power and having at least one aspheric lens surface, and a second lens component having positive refractive power and having at least one aspheric lens surface. The imaging lens satisfies two specified conditions so as to favorably correct distortion and curvature of field while providing a sufficient distance from the imaging lens to the exit pupil of the imaging lens. In addition, one or more of the lens components may each be formed of a single lens element.

Abstract: A miniature image capturing lens includes an aperture diaphragm; and a lens system consisting of a first lens having a positive refracting power in which a convex surface of the first lens is directed toward an image; and a meniscus-shaped second lens in which a concave surface of the meniscus is directed toward an object. The aperture diaphragm, the first lens and the second lens are aligned in this order from the object side, the fist and second lenses have at least one aspherical surface. The following conditional formulas are satisfied: 0.50<f1/f<0.80 0.30<(R2+R1)/(R1−R2)<1.20 where f1 is a focal length of the first lens, f is a focal length of the entire image capturing lens, R1 is a radius of curvature of the object side surface of the first lens, and R2 is a radius of curvature of the image side surface of the second lens.

Abstract: An imaging lens comprising, in sequence from the object side to the image side: an aperture diaphragm, a first lens, a second diaphragm, and a second lens; the first lens consisting of a meniscus-shaped lens having positive power with a concave face oriented towards the object side; the second lens consisting of a meniscus-shaped lens with a concave face oriented towards the image side; wherein at least one face of the first lens is an aspherical face, and one or more faces of the second lens is an aspherical face, in such a manner that the imaging lens as a whole is a lens system comprising at least two aspherical faces, and satisfying each of the following condition equations (1), (2), (3). 0.01<|f1|/|f2|<0.6  (1) 0.3f<|R2|<0.6f  (2) 0.5f<D0<1.

Abstract: A lens assembly particularly suited to use with high resolution digital cameras and other portable electronic devices. The lens includes a positive powered front group having one or two elements and a second, aberration correcting, rear group having in order from the front a bi-concave element, a meniscus element and a bi-concave element. The aperture stop plane is just in front of the front group. A combined operator and shutter device is positioned at the aperture stop plane. All of the lens elements are made of glass and have spherical surfaces.