Abstract: A zoom lens includes, arranged in order from an object side to an image plane side, a first lens group having a positive optical power, fixed with respect to an image plane; a second lens group having a negative optical power, movable in a direction parallel to an optical axis for performing a zooming action; a third lens group having a positive optical power, including a movable lens element having at least one aspherical surface and movable in a direction perpendicular to the optical axis for compensating for a blurred image; and a fourth lens group having a positive optical power, movable in the direction parallel to the optical axis for adjusting a focus, the zoom lens satisfies the predetermined conditional expression.

Abstract: A zoom lens includes, a first lens unit (1) having a positive refractive power and is fixed with respect to an image plane; a second lens unit (2) having a negative refractive power and causing a variable power action when moved along an optical axis; an aperture stop (6) fixed with respect to the image plane; a third lens unit (3) having a positive refractive power and fixed with respect to the optical axis direction when zooming and when focusing; a fourth lens unit (4) having a negative refractive power and fixed with respect to the image plane; and a fifth lens unit (5) having a positive refractive power and moveable along the optical axis such that the image plane, which is displaced by a movement of the second lens unit along the optical axis and by a movement of the object, is maintained at a constant position from a reference plane. The entire third lens unit is moveable in a direction perpendicular to the optical axis. A condition, 0.035<|?w·?t/Z|<0.

Abstract: A first lens group (G1) fixed with respect to the image plane includes a lens (11) having a negative refractive power, a lens (12) having a positive refractive power and a lens (13) having a positive refractive power. A second lens group (G2) has a negative refractive power as a whole, and causes a zooming action when moved along the optical axis. An aperture stop is fixed with respect to the image plane. A third lens group (G3) includes a lens (31) having a negative refractive power and a lens (32) having a positive refractive power, has a positive or negative refractive power as a whole, and is fixed with respect to the direction of the optical axis when zooming and when focusing. A fourth lens group (G4) has a positive refractive power as a whole, and moves along the optical axis such that the image plane, which is displaced by a movement of the second lens group (G2) along the optical axis and by a movement of the object, is maintained at a constant position with respect to a reference plane.

Abstract: A zoom lens includes, a first lens unit (1) having a positive refractive power and is fixed with respect to an image plane; a second lens unit (2) having a negative refractive power and causing a variable power action when moved along an optical axis; an aperture stop (6) fixed with respect to the image plane; a third lens unit (3) having a positive refractive power and fixed with respect to the optical axis direction when zooming and when focusing; a fourth lens unit (4) having a negative refractive power and fixed with respect to the image plane; and a fifth lens unit (5) having a positive refractive power and moveable along the optical axis such that the image plane, which is displaced by a movement of the second lens unit along the optical axis and by a movement of the object, is maintained at a constant position from a reference plane. The entire third lens unit is moveable in a direction perpendicular to the optical axis. A condition, 0.035<|?w·?t/Z|<0.

Abstract: A zoom lens, having a camera shake correction function, that is capable of preventing degradation of chromatic aberration while correcting camera shake, and can be small, light-weight and power-saving, is provided. The zoom lens is composed of four groups of lenses having positive, negative, positive and positive refractive powers, arranged in that order from an object side to an image plane side, where a second lens group conducts zooming and a fourth lens group conducts focus adjustment. The second lens group is made of a concave meniscus lens, a concave lens, a double convex lens, and a concave lens, arranged in that order from the object side to the image plane side, and it includes also at least one aspheric surface. A third lens group includes a cemented lens having a cemented surface whose convex surface faces the object side, and can be shifted in a perpendicular direction with respect to an optical axis in order to correct image fluctuations during a camera shake.

Abstract: A zoom lens capable of correcting camera shake and being reduced in size and weight, comprising five groups of lenses respectively having positive, negative, positive, negative, positive refractive powers, the second lens group (12) varying power, the fifth lens group (15) adjusting focusing. The third lens group (13) is moved in a direction perpendicular to the optical axis when correcting camera shake. When lens power on the object side of a cemented lens in the first lens group (11) is ?11, lens power on the image plane side ?12, the Abbe number of a lens on the object side ?d11, and the Abbe number of a lens on the image plane side ?d12, the condition of the following Expression 82 is satisfied: ?75<?d11?d12(?11+?12)/(?11?d12+?12?d11)<?50.Expression 82.

Abstract: Provided from the object side are a first lens group (11) having a positive refracting power and fixed to the image plane, a second lens group (12) having a negative refracting power and a magnification varying action exhibited when moving along the optical axis, a third lens group (13) fixed to the image plane and having a positive refracting power, and a fourth lens group (14) movable along the optical axis so as to maintain the image plane moving with the movements of the second lens group (12) and of the object in a fixed position from a reference plane. Hence the movement of the image due to camera shake is corrected by moving the whole third lens group (13) vertically to the optical axis. The size is reduced and the aberrations are small because the whole groups whose optical performance is united are decentered.

Abstract: A zoom lens, having a camera shake correction function, that is capable of preventing degradation of chromatic aberration while correcting camera shake, and can be small, light-weight and power-saving, is provided. The zoom lens is composed of four groups of lenses having positive, negative, positive and positive refractive powers, arranged in that order from an object side to an image plane side, where a second lens group conducts zooming and a fourth lens group conducts focus adjustment. The second lens group is made of a concave meniscus lens, a concave lens, a double convex lens, and a concave lens, arranged in that order from the object side to the image plane side, and it includes also at least one aspheric surface. A third lens group includes a cemented lens having a cemented surface whose convex surface faces the object side, and can be shifted in a perpendicular direction with respect to an optical axis in order to correct image fluctuations during a camera shake.

Abstract: Provided from the object side are a first lens group (11) having a positive refracting power and fixed to the image plane, a second lens group (12) having a negative refracting power and a magnification varying action exhibited when moving along the optical axis, a third lens group (13) fixed to the image plane and having a positive refracting power, and a fourth lens group (14) movable along the optical axis so as to maintain the image plane moving with the movements of the second lens group (12) and of the object in a fixed position from a reference plane. Hence the movement of the image due to camera shake is corrected by moving the whole third lens group (13) vertically to the optical axis. The size is reduced and the aberrations are small because the whole groups whose optical performance is united are decentered.

Abstract: A zoom lens includes, arranged in order from an object side to an image plane side, a first lens group having a positive optical power, fixed with respect to an image plane; a second lens group having a negative optical power, movable in a direction parallel to an optical axis for performing a zooming action; a third lens group having a positive optical power, including a movable lens element having at least one aspherical surface and movable in a direction perpendicular to the optical axis for compensating for a blurred image; and a fourth lens group having a positive optical power, movable in the direction parallel to the optical axis for adjusting a focus, the zoom lens satisfies the predetermined conditional expression.

Abstract: A zoom lens capable of correcting camera shake and being reduced in size and weight, comprising five groups of lenses respectively having positive, negative, positive, negative, positive refractive powers, the second lens group (12) varying power, the fifth lens group (15) adjusting focusing. The third lens group (13) is moved in a direction perpendicular to the optical axis when correcting camera shake.

Abstract: A plurality of types of ink having different wavelength characteristics are used for multiple printing of code information. When two or more types of ink are to be printed in an overlapping manner, in a region 8 in which one type of ink 4 and another type of ink 5 are printed in the overlapping manner, the ink 4 and the ink 5 are printed so as not to completely overlap each other by using a checkered pattern 9. As a result, the multiple printing can be performed without strict constraints on the wavelength characteristics of the ink.

Abstract: The aspherical zoom lens of the invention includes sequentially from an object side: a first lens group which has a positive refractive power and is fixed relative to an image plane; a second lens group which has a negative refractive power and is movable on an optical axis of the aspherical zoom lens so as to have a magnification changing function; a third lens group which has a positive refractive power and is fixed relative to the image plane so as to have a light converging function; and a fourth lens group which has a positive refractive power and is movable on the optical axis so that the image plane displaceable in response to travel of the second lens group and movement of the object is fixed at a position spaced by a predetermined distance from a reference face. An air space is provided between the third and the fourth lens groups.

Abstract: A wide-conversion lens for attachment to a master lens system consists of a bi-negative first lens in a object side and a bi-positive second lens in a master lens side, and in the second lens its radii of curvature of both surfaces are selected the same.

Abstract: In a wavelength-selective phase-grating type optical low-pass filter including at least a pair of adjacent first and second transparent layers, there is provided at least one adhesive layer through which a pair of adjacent first and second transparent layers stacked on each other in a phase grating form for generating a phase difference distribution on the boundary surface between the pair of adjacent first and second transparent layers. The optical low-pass filter satisfies the following conditions under a condition of 470 nm<.lambda.<580 nm: (a) No (.lambda.)=Ni (.lambda.), (b) .nu.d1<.nu.d2 or .nu.d1>.nu.d2, and (c) 0.9< Np(.lambda.) / No(.lambda.)< 1.1, where .lambda. is a wavelength of light passing through the optical low-pass filter, No (.lambda.) and Ni (.lambda.) are refractive indexes of the first and second transparent layers, respectively, at the wavelength .lambda., .nu.d1 and .nu.d2 are Abbe's numbers of the first and second transparent layers, respectively, No(.lambda.