Abstract: In a color separation prism that includes a first and second prism blocks bonded to each other, the first and second prism blocks are bonded to the first and second adhesive portions of the first and second base plates, respectively. The first and second base plates are fixed to the first and second base plate-fixing portions of a base with the first and second base-fixing portion interposed therebetween, respectively. The second adhesive portion is disposed between the first and second base plate-fixing portions so that a direction in which the second base plate-fixing portion is displaced from the first base plate-fixing portion and a direction in which the second adhesive portion is displaced from the second base-fixing portion are opposite to each other in a case in which the base and the second base plate expand or contract due to a change in temperature.

Abstract: In a color separation prism that includes a first and second prism blocks bonded to each other, the first and second prism blocks are bonded to the first and second adhesive portions of the first and second base plates, respectively. The first and second base plates are fixed to the first and second base plate-fixing portions of a base with the first and second base-fixing portion interposed therebetween, respectively. The second adhesive portion is disposed between the first and second base plate-fixing portions so that a direction in which the second base plate-fixing portion is displaced from the first base plate-fixing portion and a direction in which the second adhesive portion is displaced from the second base-fixing portion are opposite to each other in a case in which the base and the second base plate expand or contract due to a change in temperature.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a biconvex shape, a second lens that has a negative refractive power, a third lens, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an object side surface and an image side surface which have aspheric shapes. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a biconvex shape, a second lens that has a negative refractive power, a third lens, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an object side surface and an image side surface which have aspheric shapes. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: Disclosed is a method of manufacturing an optical element capable of increasing surface accuracy of an optical surface of an optical element with a plastic lens portion. A cavity which is formed when a pair of molds are closed has a compression molding space and an annular injection molding space, and the method includes a compression molding step of casting a compression molding material into the compression molding space of the molds and an injection molding step of injecting an injection molding material into the injection molding space in a state where the molds are closed and forming an injection molded portion at the outer circumferential edge of the compression molded compression molding material. In the injection molding step, before the compression molding material reaches a temperature lower than the glass transition temperature, the injection of the injection molding material starts.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a positive refractive power and has a meniscus shape which is concave toward an image side, a second lens that has a negative refractive power and has a meniscus shape which is concave toward the image side, a third lens that has a negative refractive power and is concave toward the object side, a fourth lens that has a positive refractive power and has a meniscus shape which is convex toward the image side, and a fifth lens that has a biconcave shape and has an aspheric shape which has at least one extreme point on an image side surface. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a positive refractive power and has a meniscus shape which is convex toward the object side, a second lens that has a negative refractive power, a third lens that has a negative refractive power, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an aspheric shape of which an image side surface has an extreme point. Further, the imaging lens satisfies a predetermined conditional expression.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a biconvex shape, a second lens that has a negative refractive power, a third lens that has a negative refractive power and has a meniscus shape which is concave toward the object side, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an aspheric shape which is concave toward an image side and of which an image side surface has an extreme point. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a positive refractive power and has a meniscus shape which is convex toward the object side, a second lens that has a negative refractive power, a third lens that has a negative refractive power, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an object side surface and an image side surface which have aspheric shapes. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: An imaging lens substantially consists, in order from an object side, five lenses of a first lens that has a positive refractive power and has a meniscus shape which is convex toward the object side, a second lens that has a negative refractive power, a third lens that has a negative refractive power, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an object side surface and an image side surface which have aspheric shapes. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a positive refractive power and is convex toward the object side, a second lens that has a negative refractive power, a third lens, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an object side surface and an image side surface which have aspheric shapes. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a biconvex shape, a second lens that has a negative refractive power, a third lens, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an object side surface and an image side surface which have aspheric shapes. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a positive refractive power and has a meniscus shape which is concave toward an image side, a second lens that has a negative refractive power and has a meniscus shape which is concave toward the image side, a third lens that has a biconcave shape, a fourth lens that has a positive refractive power and has a meniscus shape which is convex toward the image side, and a fifth lens that has a biconcave shape and has an aspheric shape which has at least one extreme point on an image side surface. Further, the imaging lens satisfies a predetermined conditional expression.

Abstract: In order to produce high-quality optical elements stably at all times without the flow of molten resin inside an injection molding cavity being hindered by the protrusion of the outer peripheral edge of a lens after compression molding, a cavity formed when a pair of molds for molding is closed is provided with: an optical-function-part molding cavity (27); an annular connection-part molding cavity (28) connected to the outer peripheral edge of the optical-function-part molding cavity; and an edge-part molding cavity (29) connected to the outer peripheral edge of the connection-part molding cavity. In a compression molding step, a protrusion part is formed by making a portion of a compression molding material bulge out from the connection-part molding cavity into the edge-part molding cavity (29). In an injection molding step, the molds are filled by injecting an injection molding material into the edge-part molding cavity (29).

Abstract: In a composite molded lens, a press-formed lens body is integral with an injection-molded lens frame. The lens body has a lens portion and a flange portion surrounding the lens portion. Eight projections are radially formed on a top surface of the flange portion. The height of the projection increases toward an outer peripheral edge side of the flange portion. A recess is formed on an outer peripheral edge face of the flange portion and located at a position on a line extending from the projection. The recess increases torsional resilience of a joint surface between the lens body and the lens frame and strengthens bonding force there between.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a biconvex shape, a second lens that has a negative refractive power, a third lens, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an object side surface and an image side surface which have aspheric shapes. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: An imaging lens substantially consists of, in order from an object side, five lenses of a first lens that has a biconvex shape, a second lens that has a negative refractive power, a third lens, a fourth lens that has a positive refractive power, and a fifth lens that has a negative refractive power and has an object side surface and an image side surface which have aspheric shapes. Further, the imaging lens satisfies predetermined conditional expressions.

Abstract: There are provided a lens that is molded with high accuracy and a method of molding the lens. The lens has an optical axis and includes a pair of optical functional surfaces on front and rear surfaces thereof. The lens includes an optical functional portion that includes the pair of optical functional surfaces, an edge portion that is provided at an outer periphery of the optical functional portion, and a connecting portion that is provided between the optical functional portion and the edge portion, connects the optical functional portion with the edge portion, and is thinner than the edge portion in a direction of the optical axis.

Abstract: In a composite molded lens, a press-formed lens body is integral with an injection-molded lens frame. The lens body has a lens portion and a flange portion surrounding the lens portion. Eight projections are radially formed on a top surface of the flange portion. The height of the projection increases toward an outer peripheral edge side of the flange portion. A recess is formed on an outer peripheral edge face of the flange portion and located at a position on a line extending from the projection. The recess increases torsional resilience of a joint surface between the lens body and the lens frame and strengthens bonding force there between.