Abstract: An image pickup lens capable of providing an angle of view of up to 70° or higher is provided. The image pickup lens can also be reduced in size and various aberrations associated with the lens can be corrected favorably, so that the image pickup lens is compatible with a high-pixel image pickup element. The image pickup lens 7 includes, in order from an object side to an image surface side: a first lens 1 that is a biconvex lens having positive power; a second lens 2 that has 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 an optical axis.

Abstract: The present invention provides an imaging lens composed of four lenses that can be made compact (downsized, thinned), allows a reduction in cost and is compatible with a high pixel imaging element having a megapixel or more incorporated in a small mobile product such as a mobile phone. The imaging lens 7 includes, in order from the object side to the image surface side: an aperture stop 5; a first lens 1 having positive power; a second lens 2 composed of a meniscus lens having negative power whose lens surface facing the image surface side is concave; a third lens 3 composed of a meniscus lens having positive power whose lens surface facing the image surface side is convex, and a fourth lens 4 having negative power whose lens surfaces are both aspheric and lens surface facing the image surface side is concave in the vicinity of the optical axis. A diffractive optical element is formed on one of the lens surfaces of the first lens 1 or one of the lens surfaces of the second lens 2.

Abstract: An image pickup lens capable of providing an angle of view of up to 70° or higher is provided. The image pickup lens can also be reduced in size and various aberrations associated with the lens can be corrected favorably, so that the image pickup lens is compatible with a high-pixel image pickup element. The image pickup lens 7 includes, in order from an object side to an image surface side: a first lens 1 that is a biconvex lens having positive power; a second lens 2 that has 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 an optical axis.

Abstract: A lens unit including a first lens including a first lens section having a first optical axis along which light passes, and a second lens. The second lens includes a second lens section having a second optical axis along which light passes, and a flange provided at the outer circumferential part of the second lens section and having a surface opposed to the first lens, and a tubular section extending from the flange in the direction of the second optical axis and having an inner side face opposed to the second lens section. The first lens is fitted in the tubular section and in contact with the inner side face of the tubular section of the second lens. The tubular section of the second lens has a plurality of protrusions protruding in the direction of the second optical axis and a plurality of valleys provided between the protrusions.

Abstract: The present invention provides an imaging lens composed of four lenses that can be made compact (downsized, thinned), allows a reduction in cost and is compatible with a high pixel imaging element having a megapixel or more incorporated in a small mobile product such as a mobile phone. The imaging lens 7 includes, in order from the object side to the image surface side: an aperture stop 5; a first lens 1 having positive power; a second lens 2 composed of a meniscus lens having negative power whose lens surface facing the image surface side is concave; a third lens 3 composed of a meniscus lens having positive power whose lens surface facing the image surface side is convex, and a fourth lens 4 having negative power whose lens surfaces are both aspheric and lens surface facing the image surface side is concave in the vicinity of the optical axis. A diffractive optical element is formed on one of the lens surfaces of the first lens 1 or one of the lens surfaces of the second lens 2.

Abstract: A photography lens 6 includes: an aperture stop 4; a first lens 1 having positive refractive power, and at least one of the lens surfaces is aspherical; a second lens 2 having negative refractive power, and at least one of the lens surfaces is aspherical; and a third lens 3 having positive refractive power, and both lens surfaces are aspherical, arranged in that order from an object side to an image surface side. When f indicates the focal length of the entire optical system, f1 indicates the focal length of the first lens 1, f2 indicates the focal length of the second lens 2, r21 indicates the radius of curvature of the lens surface of the second lens 2 facing the object side, and n2 indicates the refractive index of the second lens 2, the following conditional expressions (1) to (3) are satisfied: 0.8<f1/f<0.9??(1) ?1.0<f2/f<0.7??(2) ?1.0<r21/((n2?1)·f)<?0.7.??(3) Thus, it is possible to provide a bright photography lens having high performance and an F number of 3.5 or less.

Abstract: A photography lens 6 includes: an aperture stop 4; a first lens 1 having positive refractive power, and at least one of the lens surfaces is aspherical; a second lens 2 having negative refractive power, and at least one of the lens surfaces is aspherical; and a third lens 3 having positive refractive power, and both lens surfaces are aspherical, arranged in that order from an object side to an image surface side. When f indicates the focal length of the entire optical system, f1 indicates the focal length of the first lens 1, f2 indicates the focal length of the second lens 2, r21 indicates the radius of curvature of the lens surface of the second lens 2 facing the object side, and n2 indicates the refractive index of the second lens 2, the following conditional expressions (1) to (3) are satisfied: 0.8<f1/f<0.9??(1) ?1.0<f2/f<0.7??(2) ?1.0<r21/((n2?1)·f)<?0.7??(3). Thus, it is possible to provide a bright photography lens having high performance and an F number of 3.5 or less.

Abstract: A camera lens unit includes a first lens including a first lens section having a first optical axis along which light runs, and a second lens. The second lens includes a second lens section having a second optical axis along which the light runs, a flange provided on an outer circumference of the second lens and having a surface facing the first lens, and a cylindrical section having an inner circumference extending from the flange along the second optical axis. The inner circumference of the cylindrical section faces the second lens section. The first lens contacts the inner circumference of the cylindrical section of the second lens and is engaged into the cylindrical section. The cylindrical section of the second lens includes plural protrusions protruding along the second optical axis, such that plural crenels are provided between the protrusions and have heights along the second optical axis lower than the protrusions. The camera lens unit prevents diffuse reflection caused by unnecessary incident light.