Abstract: A lens barrel assembly has a first groove formed in a stationary barrel. A second groove is formed in a rotatable barrel. A diaphragm control plate portion is disposed between an inner surface of the rotatable barrel and an iris diaphragm device in a rotatable manner in a circumferential direction, has an end portion connected to a driving ring. An engaging groove is formed in the diaphragm control plate portion to extend along the optical axis. An operable aperture ring is disposed outside the stationary barrel. A pin device has first and second end portions, the first end portion being secured fixedly to the aperture ring, the second end portion being inserted through the first and second grooves and the engaging groove, for operating upon rotation of the aperture ring to cause the engaging groove to rotate the diaphragm control plate portion to actuate the driving ring.

Abstract: A zoom lens includes, in order from an object side to an image side, a first lens unit having a negative refractive power and a second lens unit having a positive refractive power. A distance between the first lens unit and the second lens unit varies during zooming. The first lens unit includes, in order from the object side to the image side, a negative lens and a positive lens of which an object-side lens surface has a convex shape. An Abbe number of a material of the positive lens of the first lens unit, a focal length of the first lens unit, a distance between an image-side lens surface of the first lens unit and an object-side lens surface of the second lens unit at a telephoto end, and focal lengths of the entire zoom lens at a wide-angle end and the telephoto end are appropriately set.

Abstract: An inner focus lens, in order from an object side to an image side, comprising: a first lens unit having positive optical power; a second lens unit having negative optical power; and a third lens unit having positive optical power, wherein the second lens unit is moved along an optical axis so that focusing from an infinite-distance object side to a short-distance object side is achieved, the first lens unit includes a bi-convex air lens, and the following conditions: 0.65<|f2/f|<5.00 and 0.5<f23/f1<9.0 (f2: a focal length of the second lens unit, f and f23: a focal length of the entire system and a composite focal length of the second and third lens units in an infinity in-focus condition, f1: a focal length of the first lens unit) are satisfied; an interchangeable lens apparatus; and a camera system are provided.

Abstract: A lens module includes a lens barrel, a first lens, a second lens, and a spacer. The lens barrel includes an object-side end and an image-side end opposite to the object-side end. The first lens is received in the lens barrel, and adjacent to the object-side end. The second lens is received in the lens barrel, and adjacent to the image-side end in relative to the first lens. The spacer is an annular plate, and includes an object-side surface, an image-side surface opposite to the object-side surface, and an inner sidewall. The spacer is positioned between the first lens and the second lens. The object-side surface faces the first lens, and the image-side surface faces the second lens. The intersection of the object-side surface and the inner sidewall forms a chamfer.

Abstract: An image pickup lens has a configuration of five lenses whose aberrations are corrected favorably despite its compactness compared to a conventional type.

Abstract: The present invention provides a micro-projection lens including first lens group, a second lens group, and a third lens group arranged in sequence along an optical axis from a screen side to a light modulator side. The first lens group has positive refractive power and includes at least an aspheric lens. The second lens group has negative refractive power and includes at least a glass tablet. The third lens group has positive refractive power and includes at least an aspheric lens. Therefore, the micro-projection lens of the present invention has a small size and high optical performance.

Abstract: An imaging lens (LN) of an imaging device (ID) is composed of an aperture stop (ST) and a lens unit (LU) having positive power. Even when the object side surface of the lens unit (LU) has a shape convexed to the side of the object, and a lens whose image side surface is concaved to the image side is used, excellent aberration performance with a short optical total length, a small sensor incidence angle and a small distortion are achieved at low cost.

Abstract: A zoom lens optical system includes a first lens unit having a positive refractive index, a second lens unit which is arranged behind the first lens unit and has a negative refractive index, a third lens unit which is arranged behind the second lens unit and has a positive refractive index, and a fourth lens unit which is arranged behind the third lens unit and has a positive refractive index. An aperture is arranged within the third lens unit to prevent reduction of shutter speed due to large diameter of the zoom lens optical system.

Abstract: It has conventionally been difficult to reduce the size of a fast lens system having an F number of about 1.4 to 2.4. In a lens system of the present invention, a positive lens element is disposed closest to an object side. A diaphragm is disposed in a widest air space in the lens system. The lens system of the present invention satisfies the following conditions: 0.05<L_1/L—TH<0.21 1.5<L—TH/Y<8 where L_1 is an interval from a lens surface located closest to the object side to a lens surface located on the object side relative to the diaphragm; L_TH is an interval from the lens surface located closest to the object side to a lens surface located closest to an image side; and Y is a maximum image height.

Abstract: In an image forming optical system which includes in order from an object side, a first lens group G1 having a positive refractive power, a second lens group G2 having a negative refractive power, a third lens group G3 having a positive refractive power, and a fourth lens group G4, and which includes maximum of five lens groups, and at the time of zooming from a wide angle end to a telephoto end, when a focal length of the overall image forming optical system is in a range of 1.2 fw to 1.8 fw, the first lens group G1 moves to be positioned more toward the object side than a position at the wide angle end, in a rectangular coordinate system in which, a horizontal axis is let to be ?d(LA) and a vertical axis is let to be nd(LA), when a straight line expressed by nd(LA)=a×?d(LA)+b(LA)(provided that a=?0.0267) is set, the image forming optical system satisfies a predetermined conditional expression.

Abstract: A lens system includes a first lens with negative refraction power, and a second lens with positive refraction power. The first lens includes a surface facing the image side having an optical portion. The lens system satisfies the formulas: (1) Y/Z<1.10;(2) G1R1/F1<?3.10; and (3) G2R2/F2>1.49, wherein Y is a distance between an end point of the optical portion and a center point of the optical portion along a direction perpendicular an optical axis, Z is a distance between the end point of the optical portion and the center point of the optical portion along the optical axis, F1 and F2 are the focal lengths of the first and second lenses, respectively, G1R1 and G2R2 respectively denote the radius of curvatures of a surface of the first lens facing the object side and another surface of the second lens facing the image side.

Abstract: Provided is a zoom lens for imaging an object on an imaging surface. The zoom lens includes, in the order from an object side to an image side thereof, a first lens group with positive refraction power, a second lens group with negative refraction power, a third lens group with positive refraction power, and a fourth lens group with positive refraction power. The first lens group includes a first surface. The zoom lens satisfies the formula: 0.15<|L3|/Lt<0.25, where L3 is a distance of the movement of the third lens group along an optical axis of the zoom lens when the zoom lens is switched between a wide-angle state and a telephoto state, and Lt is a distance from the first surface to the imaging surface.

Abstract: A lens system includes a first to fifth lenses. The second and fifth lenses have negative refractive power and the others have positive refractive power. The lens system satisfies: D/TTL>1.05; Z/Y>0; G3R1/F3>G1R1/F1>0; G1R2/F1<G3R2/F3<0; and G5R1/F5<G5R2/F5<0, where D is the diameter of the optical images of the lens system, TTL is the total length of the lens system, Z is the distance between the outer periphery of an image-side surface of the fourth lens to the center of an object-side surface of the fourth lens, Y is the distance between the outer periphery of the fourth lens to the center of the fourth lens, G1R1, G2R2, G3R1, G3R2, G5R1 G5R2 are the radii of curvature of the object-side and image-side surfaces of the first, third, fifth lenses, respectively, and F1, F3, F5 are focal lengths of the first, third, fifth lenses, respectively.

Abstract: A lens array includes a first lens row including first lenses arranged in a first direction, a second lens row including second lenses arranged in a direction substantially parallel with the first direction, a first boundary being a boundary between the first lenses adjacent to each other, a second boundary being a boundary between each of the first lenses and the second lens adjacent to the first lens, and a first join portion where the first boundary and the second boundary join each other. At the first joint portion, the first boundary and the second boundary contact each other with no step as seen in a plane that is substantially orthogonal to the first direction.

Abstract: An image pickup lens compatible with small high-pixel image pickup elements (e.g., from CCD and CMOS image sensors having a pixel pitch of 1.75 ?m and a pixel count of 5 mega pixels to CCD and CMOS image sensors having a pixel pitch of 1.4 ?m and a pixel count of 8 mega pixels) is provided. An image pickup lens 7 includes, in order from an object side to an image surface side: an aperture stop 5, a first lens 1 having positive power; a second lens 2 that is a meniscus lens having negative power and whose lens surface facing the image surface side is concave; a third lens 3 that is a meniscus lens having positive power and whose lens surface facing the image surface side is convex; and a fourth lens 4 that has negative power, whose lens surfaces are both aspherical and whose lens surface facing the image surface side is concave near the optical axis. A diffractive optical element is formed on one of the lens surfaces of the first lens 1 or the second lens 2.

Abstract: A projector includes: first and second light blocking members adapted to partially block a light beam from a light source, and a drive section adapted to make the first and second light blocking members perform an opening and closing operation. When the corresponding first and second light blocking members are located at a maximum blocking state, with respect to an opening and closing direction of the first and second light blocking members perpendicular to a system optical axis, a first and second support sections support the first and second light blocking members at predetermined positions on the system optical axis side from intermediate positions corresponding to midpoints of areas between edge portions of the first and second light blocking members on the system optical axis side and parts, to which outer edges of the light beam to be blocked are input.

Abstract: A lens optical system having first to fourth lenses sequentially arranged from an object, and between the object and an image sensor on which an image of the object is formed. The first lens has a positive refractive power and is convex toward the object. The second lens has a negative refractive power and is biconcave. The third lens has a positive refractive power and is convex toward the image sensor. The fourth lens has a negative refractive power and at least one of an incident surface and an exit surface of the fourth lens is an aspherical surface. An aperture may be arranged between the first and second lenses.

Abstract: A large caliber standard lens having a first lens of a positive refractive power; a second lens of a negative refractive power; a diaphragm; a third lens of a negative refractive power; a fourth lens of a positive refractive power; and a fifth lens of a positive refractive power, wherein the lenses are arranged sequentially from an object side to an image side, and the first lens, the second lens, the third lens, and the fourth lens are meniscus lenses having concave surfaces facing the diaphragm and satisfy the following inequality, 0.6 ? ? R 6 R 4 ? ? 1.0 where R4 represents the radius of curvature of the surface of the second lens facing the image, and R6 represents the radius of curvature of the surface of the third lens facing the object.

Abstract: The lens apparatus includes an aperture stop (SP) forming an aperture, a first lens (A or B) disposed on a first side further than the aperture stop, the first side being one of an object side and an image side, and a second lens (B or A) disposed on a second side further than the aperture stop, the second side being the other of the object side and the image side. In zooming or focusing, the aperture stop is moved independently of the first and second lenses. The first lens and the aperture stop are brought into a first state where an aperture stop side lens surface of the first lens is located away from the aperture stop on the first side and a second state where at least part of the aperture stop side lens surface (RA or RB) of the first lens protrudes through the aperture to the second side further than the aperture stop.

Abstract: A retrofocus wide-angle lens system is provided, wherein the entire the wide-angle lens system is divided at a position that satisfies the following condition (1) between a theoretical front lens group having a negative refractive power, and a theoretical rear lens group having a positive refractive power including the diaphragm, at a minimum focal length, and wherein a flat parallel plate is disposed at the position that satisfies the following condition (1): 1.2<|fF/f|<4.0 . . . (1), wherein fF designates the focal length of the theoretical front lens group having a negative refractive power, and f designates the focal length of the entire the wide-angle lens system.

Abstract: An imaging device is provided with an imaging sensor having a rectangular imaging surface, an image-forming optical system for forming an image onto the imaging surface, and a prism disposed between the image-forming optical system and the imaging sensor for bending an optical path. A mask, having a rectangular opening, limits light that is to be incident on the imaging sensor. The aspect ratio (long side/short side) of the mask rectangular opening of the mask is larger than that of the rectangular imaging surface, and the peripheral light quantity difference between the short and long sides on the rectangular imaging surface is smaller than in the case of these two aspect ratios being equal to each other.

Abstract: An optical image lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element and a fourth lens element. The first lens element with positive refractive power has a convex object-side surface. The second lens element has refractive power. The third lens element with refractive power is made of plastic material, wherein an object-side surface and an image-side surface of the third lens element are aspheric. The fourth lens element with negative refractive power is made of plastic material, and has a concave image-side surface, wherein an object-side surface and the image-side surface of the fourth lens element are aspheric, and the fourth lens element has at least one inflection point formed on at least one of the object-side surface and the image-side surface thereof.

Abstract: It has conventionally been difficult to reduce the size of a fast lens system having an F number of about 1.4 to 2.4. In a lens system of the present invention, a positive lens element is disposed closest to an object side. A diaphragm is disposed in a widest air space in the lens system. The lens system of the present invention satisfies the following conditions: 0.05<L_1/L—TH<0.21 1.5<L—TH/Y<8 where L_1 is an interval from a lens surface located closest to the object side to a lens surface located on the object side relative to the diaphragm; L_TH is an interval from the lens surface located closest to the object side to a lens surface located closest to an image side; and Y is a maximum image height.

Abstract: A zoom lens comprising, in order from an object side: a first lens group G1 having positive refractive power; a second lens group G2 having negative refractive power; and a third lens group G3 having positive refractive power; each distance between said lens groups adjacent to each other changing upon zooming from a wide-angle end state to a telephoto end state, said first lens group G1 having a cemented lens including a negative lens L11, and said third lens group G3 having a cemented lens L32 and L33, and a given conditional expression being satisfied, thereby providing a downsized zoom lens having high optical performance.

Abstract: A zoom lens includes a first lens group of negative refractive power, a second lens group of positive refractive power and a third lens group of positive refractive power. The zoom lens satisfies the following condition formulas: 0.68<|f2/f1|<0.85, and 0.65<L2/fT<0.86, where f1 represents an effective focal length of the first lens group, f2 represents an effective focal length of the second lens group, L2 is a displacement of the second lens group when the zoom lens varies from a wide-angle state to a telephoto state, and fT represents an effective focal length of the zoom lens which is in the telephoto state.

Abstract: A zoom lens system comprising: a front unit having negative optical power as a whole and including a first lens unit located closest to the object side; and a rear unit having positive optical power as a whole, wherein at least the front unit moves along an optical axis in zooming, the first lens unit is composed of at most three lens elements, the rear unit includes a lens unit having an aperture diaphragm between lens elements, an air space between which is not varied in zooming, a sub lens unit comprising a part of a lens unit constituting the rear unit moves in a direction perpendicular to the optical axis, and the condition: 0.1<BF/fW<2.0 (?W>72°, FNOW<2.9, BF is a back focal length of the entire system at a wide-angle limit, fW is a focal length of the entire system at a wide-angle limit, ?W is a view angle at a wide-angle limit, FNOW is an F-number at a wide-angle limit) is satisfied; an imaging device; and a camera are provided.

Abstract: An photographing optical lens assembly includes, in order from an object side to an image side, a first lens element with positive refractive power, a second lens element with negative refractive power having a concave object-side surface and a concave image-side surface, a plastic third lens element with positive refractive power having a concave aspheric object-side surface and a convex aspheric image-side surface, a plastic fourth lens element with negative refractive power having a concave aspheric object-side surface and a convex aspheric image-side surface and a plastic fifth lens element having an aspheric object-side surface and an aspheric image-side surface. By adjusting the focal lengths of the second and the fourth lens element and the photographing optical lens assembly, and the curvature radii of the object-side and the image-side surface of the second lens element, the photographing optical lens assembly is miniaturized, and the image quality is improved.

Abstract: An optical image capturing lens assembly includes, in order from an object side to an image side, a first lens element, a second lens element, a third lens element, a fourth lens element, a fifth lens element, and a sixth lens element. The first lens element with positive refractive power has a convex object-side surface. The object-side surface and the image-side surface of the fifth lens element are aspheric and at least one of the object-side surface and the image-side surface has at least one inflection point formed thereon. The sixth lens element with negative refractive power has a concave object-side surface and a convex image-side surface, wherein the object-side surface and the image-side surface of the sixth lens element are aspheric.

Abstract: An imaging optical system includes an aperture stop, a first lens group disposed on an object side of the aperture stop, a second lens group disposed on an image side of the aperture stop and a plate-like ND filter disposed close to a position of the aperture stop in an optical axis direction of the first and second lens groups, and the second lens group includes positive refracting power as a whole, the ND filter is configured to be retractable from the optical axis, and to attenuate a passing light amount.

Abstract: A fixed-focus lens disposed between an enlarged side and a reduced side is provided. An f-number of the fixed-focus lens is smaller than or equal to 2. The fixed-focus lens includes a first lens group and a second lens group. The first lens group includes a first lens, wherein the first lens is an aspheric lens. The second lens group, disposed between the first lens group and the reduced side, has a positive dioptre. The second lens group includes a second lens, wherein the second lens is an aspheric lens. The fixed-focus lens focuses by moving the first and the second lens group and satisfies 0.1<|f/f1|<1, 0.2<|f/f2|<1.5, and 1.5<L/BEL<3.5, where f, L, and BFL are respectively a focal length, a total length, and a back focal length of the fixed-focus lens, and f1 and f2 are respectively an effective focal length of the first and the second lens group.

Abstract: A single focus wide-angle lens module includes a fixed aperture diaphragm, a first, a second, a third and a forth lens arranged from an object side to an image side in the following sequence: the first lens, the fixed aperture diaphragm, the second lens, the third lens and the forth lens. The first lens has a negative refractive power, a concave surface toward the image side, and at least one aspheric surface. The second lens has a positive refractive power and a concave surface toward the object side, and said second lens is made of glass. Further, the third lens has a meniscus shape, a positive refractive power, a concave surface toward the object side, and at least one aspheric surface. The fourth lens has a positive refractive power, a convex surface toward the object side, and at least one aspheric surface.

Abstract: There is provided a method of manufacturing a lens, including applying a second lens material to a first lens member made of a first lens material; aligning and fixing a light shielding member to the second lens material; and further applying the second lens material to the first lens member and performing curing thereon to complete a second lens member.

Abstract: A lens module includes a lens barrel, a first lens, a second lens, and a spacer. The lens barrel includes an object-side end and an image-side end opposite to the object-side end. The first lens is received in the lens barrel, and adjacent to the object-side end. The second lens is received in the lens barrel, and adjacent to the image-side end in relative to the first lens. The spacer is an annular plate, and includes an object-side surface, an image-side surface opposite to the object-side surface, and an inner sidewall. The spacer is positioned between the first lens and the second lens. The object-side surface faces the first lens, and the image-side surface faces the second lens. The intersection of the object-side surface and the inner sidewall forms a chamfer.

Abstract: An optical lens for image pickup, sequentially arranged from an object side to an image side, comprising: the first lens element with positive refractive power having a convex object-side surface, the second lens element with negative refractive power having a convex object-side surface and a concave image-side surface, the plastic third lens element with positive refractive power having a concave object-side surface and a convex image-side surface with both being aspheric, the plastic fourth lens element with positive refractive power having a convex object-side surface and a concave image-side surface with both being aspheric. By such arrangements, the optical lens for image pickup satisfies conditions related to reduce the sensitivity and to shorten the total length for use in compact cameras and mobile phones with camera functionalities.

Abstract: The present invention provides an image-capturing optical lens assembly comprising, in order from an object side to an image side, a front lens group, a stop, and a rear lens group. The front lens group comprises, in order from the object side to the image side: a first lens element with negative refractive power having a convex object-side surface and a concave image-side surface; and a second lens element with positive refractive power having a convex object-side surface and a concave image-side surface. The rear lens group comprises, in order from the object side to the image side: a third lens element with positive refractive power having a convex object-side surface and a convex image-side surface; a fourth lens element with negative refractive power; and a fifth lens element with positive refractive power having a convex image-side surface.

Abstract: A zoom lens comprising, in order from an object side thereof, a first lens group of positive refracting power, a second lens group of negative refracting power, an aperture stop, a third lens group of positive refracting power, a fourth lens group of negative refracting power, and a fifth lens group of positive refracting power. Upon zooming from the wide-angle end to the telephoto end, at least the first lens group and the aperture stop remain fixed in position, the second and third lens groups move in the optical axis direction, and the separation between each of the lens groups and the aperture stop changes. Upon focusing from a focusing-on-infinity state to a close-range-focusing state, the fourth lens group moves in the optical axis direction, with satisfaction of the following: ?0.36<f4/f1<?0.05??(1A), where fl and f4 are the focal lengths of the first and fourth lens groups, respectively.

Abstract: A zoom optical system comprising, in order from the object side, a first lens unit with negative power, a second lens unit with positive power, a third lens unit with positive power, and a fourth lens unit, wherein spacing between the first lens unit and the fourth lens unit is fixed to an image surface, and the second lens unit and the third lens unit are moved on an optical axis so as to change spacings between the respective lens units when the magnification of the zoom optical system is changed. The third lens unit comprises lens elements more than three, including an aperture stop, at least a lens element with positive power and at least a lens element with negative power, and the most image-side lens element of the third lens unit is a meniscus lens element with a concave surface facing the image side.

Abstract: A high-performance zoom lens system which is compact and has a wide view angle at a wide-angle limit and a high zooming ratio in a balanced manner, in order from an object side to an image side, comprising a first lens unit having positive optical power, a second lens unit having negative optical power, a third lens unit having positive optical power, and a fourth lens unit having positive optical power, wherein the first lens unit is composed of at most two lens elements, the second lens unit is composed of two lens elements, the third lens unit is composed of three lens elements, in order from the object side to the image side, including an object side lens element having positive optical power, a lens element having negative optical power, and an image side lens element having positive optical power, and the conditions: ?2.0<f2/fW<?1.1, fT/fW>6.

Abstract: A zoom lens includes in order from an object side to an image side and arranged along an optical axis thereof, a first lens unit having a negative refractive power, and a second lens unit having a positive refractive power. A distance between each lens unit changes when zooming from a wide-angle end to a telephoto end. The first lens unit includes a first lens sub-unit including a positive lens element and a negative lens element, and having a negative refractive power, and a second lens sub-unit including a single negative lens element. Focusing is performed by moving the second lens sub-unit in an optical axis direction, a focal length of the second lens sub-unit f1b and a focal length of the entire zoom lens fw at a wide-angle end are suitably set based on predetermined mathematical expressions.

Abstract: A zoom lens including, in a sequence from an object side, a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a succeeding lens group having an overall positive refractive power, and having a high zoom magnification and a compact size.

Abstract: A lens module includes a lens barrel, a first lens, an opaque plate, and a second lens. The first lens includes an imaging portion and a non-imaging portion surrounding the imaging portion. The non-imaging portion defines an annular conic surface. The opaque plate is annular conic shaped and contacts with the annular conic surface. The second lens includes an imaging portion and a non-imaging portion surrounding the imaging portion. The object-side surface of the non-imaging portion of the second lens is step-like shaped and includes at least two step surfaces. A junction of two adjacent step surfaces abuts against the opaque plate.

Abstract: The present invention is directed to an inner focusing macro lens that has a large aperture ratio as expressed by 2.5 or even smaller in F-number and still remains compact, and that is adapted to compensate for spherical aberration, astigmatism, and comatic aberration during photographing throughout the entire object distance ranging from infinity to proximity for an up to 1:1-magnification image. The inner focusing macro lens has the leading or first lens group of positive refractivity, the second lens group of negative refractivity, the third lens group of positive refractivity, and the trailing lens set succeeding to the third lens group in sequence from a position closest to an object being photographed. During focusing from a point infinitely far to that as proximal as desired, the first lens group is static while the second lens group is moved toward the imaging plane, and the third lens group is moved toward the object.

Abstract: Image pickup lens unit (100) comprises, in order to minimize the positional displacement between an optical system and a holder therefor, compound lens (6), holder (2) which houses compound lens (6) therein, and cover (4) which covers compound lens (6). In holder (2), there is formed peripheral section (2e) which restricts the movement of compound lens (6) in the XY-direction. In cover (4), there is formed projecting section (4e) which restricts the movement of compound lens (6) in the Z-direction.

Abstract: A zoom optical system in which: a positive first lens group, a negative second lens group, a positive third lens group, and a positive fourth lens group are arranged in that order from the object side and magnification is changed by properly changing distances between these lens groups; the first lens group consists of only one lens element and the most object-side surface of the first lens group has a convex shape which faces toward the object side; the second lens group includes, in order from the object side, a negative single lens, a negative cemented lens, and a positive single lens; and the following condition (1) or (2) is satisfied: 0.2??Dw-w10/Lt?0.

Abstract: An optical system for observation of a front-direction object and a substantially-lateral-direction object includes, in order from the front-direction-object side, a front group with a negative refracting power having a reflecting/refracting optical element, an aperture stop, and a rear group with a positive refracting power having a moving lens component movable along the optical axis. The reflecting/refracting optical element has a first face formed on the front-direction-object side, a second face formed on the image side, and a third face formed as a transmitting surface between the first face and the second face. The first face has a first transmitting surface formed with the optical axis being at a center thereof and a first reflecting surface annularly formed around the first transmitting surface and directed toward an image side.

Abstract: An imaging lens includes, sequentially from an object side, a positive first lens; a negative second lens; a positive third lens having a convex surface on an image plane side; a fourth lens that is a meniscus lens having a convex surface on the image plane side; and a fifth lens having a refractive power that gradually changes from negative at the lens center to positive at the lens periphery, where the first lens and the second lens are disposed having an interval therebetween.

Abstract: A lens array includes a plurality of lens assembly members with a plurality of lenses, a light blocking member with a plurality of apertures arranged therein, and a light blocking member including a plurality of apertures arranged therein. The lens assembly members are arranged so that an optical axis of each of the lenses of one of the lens assembly members is aligned with an optical axis of each of the lenses of another of the lens assembly members. Further, the lens assembly members and the light blocking member are arranged so that the following relationship is satisfied: P 2 ? RY ? LO - F F where P is a pitch of the lenses, F is a focal length of each of the lenses, LO is a distance between an object surface and each of the lenses, and RA is a distance between the optical axis and an inner surface of the aperture.

Abstract: A zoom lens includes a positive first lens group, a negative second lens group, a positive third lens group, and a positive fourth lens group, which are arranged in this order from the object side of the zoom lens. The focal length of the entire system of the zoom lens is changeable by changing a distance between the second lens group and the third lens group. The first lens group includes two cemented lenses, each composed of a negative meniscus lens and a positive lens cemented together in this order from the object side, and a positive lens, and the two cemented lenses and the positive lens being arranged in this order from the object side. Further, a predetermined formula related to the focal length of the first lens group and the focal length of the entire system is satisfied.

Abstract: A blade drive device includes: a board including an optical path opening; first and second blades cooperatively defining an amount of light passing through the optical path opening to a given amount of light. The first blade includes a first opening. The second blade includes: a first cutout portion defining the amount of light in cooperation with the first opening; and a second cutout portion defining the amount of light in cooperation with the first opening. The second cutout portion overlaps the first blade when the first cutout portion and the first opening cooperatively define the amount of light.

Abstract: When the lens barrel is in the storage state, a part of a lens group and a group cylinder are inserted into an aperture of a diaphragm unit and a shutter blade of a shutter unit is closed for light shielding. With this arrangement, the cylinder length in the storage state is shortened, and the performance degradation of an image sensor and optical components provided on a front side of an image sensor can be prevented as well.