Abstract: An imaging lens consists of five lenses consisting of, in order from the object side, a biconvex first lens, a biconcave second lens, a positive third lens having a meniscus shape with the convex surface toward the image side, a positive fourth lens having a meniscus shape with the convex surface toward the image side, and a negative fifth lens having a concave surface toward the image side, and having at least one inflection point on the image-side surface thereof, wherein condition expression (1), 0<f/f3<0.6, relating to the focal length f of the entire system and the focal length f3 of the third lens, and condition expression (2), 0.12<D7/f<0.3, relating to the focal length f of the entire system and the distance D7 between the third lens and the fourth lens along the optical axis are satisfied.

Abstract: An imaging lens consists of a front group having positive refractive power as a whole and a rear group in this order from an object side. The front group consists of three positive lenses, a negative lens with its concave surface facing an image side, a positive lens with its convex surface facing the object side, a negative lens with its concave surface facing the image side, a stop, a negative lens with its concave surface facing the object side and plural positive lenses in this order from the object side. The rear group has positive refractive power and consists of a positive lens and a negative lens in this order from the object side.

Abstract: An imaging lens is essentially constituted by five lenses, including: a first lens having a positive refractive power and a convex surface toward the object side; a second lens of a biconcave shape; a third lens having a positive refractive power and is of a meniscus shape with a concave surface toward the object side; a fourth lens having a negative refractive power and a concave surface toward the object side; and a fifth lens having a negative refractive power and a concave surface toward the image side, provided in this order from the object side. The imaging lens satisfies predetermined conditional formulae.

Abstract: An imaging lens is substantially constituted by five lenses, including: a first lens having a positive refractive power and a convex surface toward the object side; a second lens having a biconcave shape; a third lens having a positive refractive power and is of a meniscus shape having a concave surface toward the object side; a fourth lens having a concave surface toward the object side; and a fifth lens having a negative refractive power and is of a meniscus shape having a convex surface toward the object side, provided in this order from the object side. The imaging lens satisfies a predetermined conditional formula.

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 is substantially constituted by five lenses, including: a first lens having a positive refractive power and a convex surface toward the object side; a second lens having a negative refractive power and a concave surface toward the image side; a third lens having a negative refractive power and a concave surface toward the object side; a fourth lens having a positive refractive power and is of a meniscus shape with a concave surface toward the object side; and a fifth lens having a negative refractive power and is of a meniscus shape having a convex surface toward the image side, provided in this order from the object side. The imaging lens satisfies a predetermined conditional formula.

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 consists of five lenses consisting of, in order from the object side, a biconvex first lens, a biconcave second lens, a positive third lens having a meniscus shape with the convex surface toward the image side, a positive fourth lens having a meniscus shape with the convex surface toward the image side, and a negative fifth lens having a concave surface toward the image side, and having at least one inflection point on the image-side surface thereof, wherein condition expression (1), 0<f/f3<0.6, relating to the focal length f of the entire system and the focal length f3 of the third lens, and condition expression (2), 0.12<D7/f<0.3, relating to the focal length f of the entire system and the distance D7 between the third lens and the fourth lens along the optical axis are satisfied.

Abstract: An imaging lens is essentially constituted by five lenses, including: a first lens having a positive refractive power and a convex surface toward the object side; a second lens of a biconcave shape; a third lens having a positive refractive power and is of a meniscus shape with a concave surface toward the object side; a fourth lens having a negative refractive power and a concave surface toward the object side; and a fifth lens having a negative refractive power and a concave surface toward the image side, provided in this order from the object side. The imaging lens satisfies predetermined conditional formulae.

Abstract: An imaging lens is substantially constituted by five lenses, including: a first lens having a positive refractive power and a convex surface toward the object side; a second lens having a negative refractive power and a concave surface toward the image side; a third lens having a negative refractive power and a concave surface toward the object side; a fourth lens having a positive refractive power and is of a meniscus shape with a concave surface toward the object side; and a fifth lens having a negative refractive power and is of a meniscus shape having a convex surface toward the image side, provided in this order from the object side. The imaging lens satisfies a predetermined conditional formula.

Abstract: An imaging lens is substantially constituted by five lenses, including: a first lens having a positive refractive power and a convex surface toward the object side; a second lens having a biconcave shape; a third lens having a positive refractive power and is of a meniscus shape having a concave surface toward the object side; a fourth lens having a concave surface toward the object side; and a fifth lens having a negative refractive power and is of a meniscus shape having a convex surface toward the object side, provided in this order from the object side. The imaging lens satisfies a predetermined conditional formula.

Abstract: An imaging lens consists of a front group having positive refractive power as a whole and a rear group in this order from an object side. The front group consists of three positive lenses, a negative lens with its concave surface facing an image side, a positive lens with its convex surface facing the object side, a negative lens with its concave surface facing the image side, a stop, a negative lens with its concave surface facing the object side and plural positive lenses in this order from the object side. The rear group has positive refractive power and consists of a positive lens and a negative lens in this order from the object side.

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: A microinterferometer applies low coherent measurement light, which travels along an optical axis in a converging manner, to a front surface of a flange. A part of the measurement light is reflected inside an interferometric optical system, and becomes reference light. Apart of the measurement light passed through the interferometric optical system is reflected from the front surface of the flange, and is incident again upon the interferometric optical system. By combining the reflected light with the reference light, interference light is obtained. While a sample rotating stage rotates a sample lens through 360 degrees, a first imaging camera having one-dimensional image sensor captures 3600 images of the interference light, i.e., the image of the interference light is captured every time the sample lens is rotated by 0.1 degrees. Based on the images of interference fringes, the shape of the front surface of the flange is analyzed.

Abstract: Through a first diffraction grating, two conical fluxes different in wavefront propagation angle relative to its optical axis are applied to a first surface. Through a second diffraction grating, two conical fluxes different in wavefront propagation angle relative to its optical axis are applied to a second surface. Two sets of interference fringes formed by the fluxes reflected from the first surface and a reference beam are analyzed to obtain surface misalignment and angular misalignment of the first surface relative to the optical axis. Similarly, two sets of interference fringes formed by the fluxes reflected from the second surface and the reference beam are analyzed to obtain surface misalignment and angular misalignment of the second surface relative to the optical axis. Surface misalignment and angular misalignment of a sample lens are obtained from the measurement results of the first and second surfaces.

Abstract: The relative position of a test surface is sequentially changed from a reference position where a surface central axis is aligned with a measurement optical axis such that the measurement optical axis is sequentially moved to a plurality of annular regions obtained by dividing the test surface in a diametric direction. The test surface is rotated on a rotation axis whenever the relative position is changed. Measurement light composed of a plane wave is radiated to the rotating test surface, and a one-dimensional image sensor captures interference fringes at each of a plurality of rotational positions. The shape information of each annular region is calculated on the basis of the captured interference fringes at each rotational position, and the shape information is connected to calculate the shape information of the entire measurement region.

Abstract: The relative position of a test surface is sequentially changed from a reference position where a surface central axis is aligned with a measurement optical axis such that the measurement optical axis is sequentially moved to a plurality of annular regions obtained by dividing the test surface in a diametric direction. The test surface is rotated on a rotation axis whenever the relative position is changed. Measurement light that travels while being converged by a Mirau objective interference optical system is radiated to the rotating test surface, and a one-dimensional image sensor captures interference fringes at each of a plurality of rotational positions. The shape information of each annular region is calculated on the basis of the captured interference fringes at each rotational position, and the shape information is connected to calculate the shape information of the entire measurement region.

Abstract: A process of measuring a shape while changing the relative posture of an microscopic interferometer to a sample lens which is rotated about a rotation axis is divided into a process of measuring a top surface in a state where the sample lens is supported from a back surface and a process of measuring a back surface in a state where the sample lens is supported from the top surface. By combining first shape information of a flange side surface acquired by the process of measuring the top surface and second shape information of the flange side surface acquired by the process of measuring the back surface, the relative positional relation between the sample top surface and the sample back surface is calculated.

Abstract: The relative position of a test surface is sequentially changed from a reference position where a surface central axis is aligned with a measurement optical axis such that the measurement optical axis is sequentially moved to a plurality of annular regions obtained by dividing the test surface in a diametric direction. The test surface is rotated on a rotation axis whenever the relative position is changed. Measurement light that travels while being converged by a Mirau objective interference optical system is radiated to the rotating test surface, and a one-dimensional image sensor captures interference fringes at each of a plurality of rotational positions. The shape information of each annular region is calculated on the basis of the captured interference fringes at each rotational position, and the shape information is connected to calculate the shape information of the entire measurement region.