Abstract: The accuracy of unsupervised anomalous sound detection is improved. An anomalous sound generation unit 12 generates a pseudo-anomalous sound by associating a sound obtained from a predetermined device with a probability distribution followed by a sound obtained from a desired device group. A threshold value setting unit 13 sets a threshold value so that all anomaly scores calculated from the pseudo-anomalous sound are determined to be anomalous. A parameter update unit 14 uses an obtained normal sound and an obtained anomalous sound, or a threshold value and a value based on the obtained anomalous sound, to update a parameter so to reliably determine an anomalous sound as anomalous and minimize the probability of determining a normal sound as anomalous.

Abstract: A threshold acquisition apparatus acquires a threshold for determining whether an anomaly score acquired from a target sound is normal or anomalous. The threshold acquisition apparatus includes: an allowable number setting unit that sets an allowable number of times such that the number of anomaly scores determined to be anomalous included in a set of anomaly scores per predetermined section length, which is a part of time-series acoustic signals that do not include an anomalous sound, does not exceed the allowable number of times; and a threshold estimation unit that estimates a threshold candidate such that the number of sections determined to be anomalous per predetermined section length, which is a part of time-series acoustic signals, satisfies a predetermined criterion by using the allowable number of times, and acquires the threshold candidate as the threshold.

Abstract: A short-wavelength infrared imaging lens includes first and second lens groups arranged in order from an object side. The first lens group has a negative refractive power as a whole. The second lens group has a positive refractive power as a whole and includes at least one positive lens that satisfies following conditional expressions (1) and (2): V2p>40??(1) N2p>1.7??(2) Here, N2p is a refractive index N [1.53] of the positive lens at a wavelength of 1.53 ?m, and the Abbe number V2p is an Abbe number of the positive lens in a short-wavelength infrared range and is defined as (N [1.53]?1)/(N [0.9]?N [2.325]) when refractive indexes of the at least one positive lens at wavelengths of 0.9 ?m, 1.53 ?m, and 2.325 ?m are represented by N [0.9], N [1.53], and N [2.325], respectively.

Abstract: A short-wavelength infrared imaging lens includes first and second lens groups arranged in order from an object side. The first lens group has a negative refractive power as a whole. The second lens group has a positive refractive power as a whole and includes at least one positive lens that satisfies following conditional expressions (1) and (2): V2p>40??(1) N2p>1.7??(2) Here, N2p is a refractive index N [1.53] of the positive lens at a wavelength of 1.53 ?m, and the Abbe number V2p is an Abbe number of the positive lens in a short-wavelength infrared range and is defined as (N [1.53]?1)/(N [0.9]?N [2.325]) when refractive indexes of the at least one positive lens at wavelengths of 0.9 ?m, 1.53 ?m, and 2.325 ?m are represented by N [0.9], N [1.53], and N [2.325], respectively.

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: A zoom lens consists essentially of a positive first lens group, a negative second lens group, a negative third lens group, and a positive fourth lens group. During zooming from the wide angle end to the telephoto end, the first lens group and the fourth lens group are fixed, the third lens group is moved monotonously from the object side to the image side, and the second lens group is moved to correct an image plane variation associated with the zooming When the amounts of movements of the second lens group and the third lens group are taken as M2 and M3 respectively, the zoom lens satisfies a conditional expression (1): 0<M2/M3<1.0, where each of M2 and M3 is given a positive sign for a movement to the image side.

Abstract: A wide angle lens includes a first lens group having negative refractive power, as a whole, a second lens group having positive refractive power, as a whole, and a third lens group having positive refractive power, as a whole, in this order from an object side. The first lens group includes a positive meniscus lens with its convex surface facing the object side and three negative meniscus lenses, each with its convex surface facing the object side, in this order from the object side. The second lens group includes at least one cemented lens. The material of at least one of the three negative meniscus lenses in the first lens group satisfies the following conditional expression (1), and the material of at least one of the other negative meniscus lenses in the first lens group satisfies the following conditional expressions (2) and (3): ?da>81??(1); ?db<25??(2); and ??gFb>0.015??(3).

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: A wide angle lens consists of a first lens group having negative refractive power as a whole, a second lens group having positive refractive power as a whole, and a third lens group having positive refractive power as a whole in this order from an object side. The first lens group consists of a positive meniscus lens with its convex surface facing the object side and three negative meniscus lenses, each with its convex surface facing the object side, in this order from the object side. The second lens group includes at least two cemented lenses. The third lens group consists of a 3a-th lens group consisting of a positive meniscus lens with its convex surface facing the object side and a 3b-th lens group that includes at least two cemented lenses and has positive refractive power as a whole, in this order from the object side.

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: A zoom lens consists essentially of a positive first lens group, a negative second lens group, a negative third lens group, and a positive fourth lens group. During zooming from the wide angle end to the telephoto end, the first lens group and the fourth lens group are fixed, the third lens group is moved monotonously from the object side to the image side, and the second lens group is moved to correct an image plane variation associated with the zooming When the amounts of movements of the second lens group and the third lens group are taken as M2 and M3 respectively, the zoom lens satisfies a conditional expression (1): 0<M2/M3<1.0, where each of M2 and M3 is given a positive sign for a movement to the image side.

Abstract: A wide angle lens includes a first lens group having negative refractive power, as a whole, a second lens group having positive refractive power, as a whole, and a third lens group having positive refractive power, as a whole, in this order from an object side. The first lens group includes a positive meniscus lens with its convex surface facing the object side and three negative meniscus lenses, each with its convex surface facing the object side, in this order from the object side. The second lens group includes at least one cemented lens. The material of at least one of the three negative meniscus lenses in the first lens group satisfies the following conditional expression (1), and the material of at least one of the other negative meniscus lenses in the first lens group satisfies the following conditional expressions (2) and (3): ?da>81??(1); ?db<25??(2); and ??gFb>0.015??(3).

Abstract: A wide angle lens consists of a first lens group having negative refractive power as a whole, a second lens group having positive refractive power as a whole, and a third lens group having positive refractive power as a whole in this order from an object side. The first lens group consists of a positive meniscus lens with its convex surface facing the object side and three negative meniscus lenses, each with its convex surface facing the object side, in this order from the object side. The second lens group includes at least two cemented lenses. The third lens group consists of a 3a-th lens group consisting of a positive meniscus lens with its convex surface facing the object side and a 3b-th lens group that includes at least two cemented lenses and has positive refractive power as a whole, 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: 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: 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.

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.