Abstract: An observation optical system includes a display element, and an eyepiece lens disposed on an eyepoint side with respect to the display element. The eyepiece lens includes a first negative lens having strongest negative refractive power among lenses included in the eyepiece lens, a first positive lens disposed adjacent to a display element side of the first negative lens, and a second positive lens disposed closest to the display element side among positive lenses disposed on the eyepoint side with respect to the first negative lens. The number of lenses included in the eyepiece lens is greater than or equal to five. The observation optical system satisfies predetermined conditional expressions.

Abstract: The imaging method is used in an imaging apparatus including an imaging element that captures a subject image and a moving mechanism configured to change a relative position between the subject image and the imaging element, the imaging method including: a changing step of changing the relative position a plurality of times; an imaging step of acquiring a plurality of first images by capturing the subject image using the imaging element at a plurality of the relative positions; a combining step of generating a second image by combining the plurality of first images; and a display step of performing a temporal display relating to the imaging step or the combining step.

Abstract: An imaging lens consisting of, in order from an object side to an image side: a first lens group; a second lens group that has a positive refractive power; and a third lens group that has a negative refractive power, wherein the first lens group includes, successively in order from a position closest to the object side to the image side, two negative lenses and a positive lens, the second lens group includes a positive lens and a negative lens, during focusing from an object at infinity to a closest object, the first lens group remains stationary with respect to an image plane, and the second lens group moves along an optical axis, and assuming that a focal length of the first lens group is f1, and a focal length of the second lens group is f2, Conditional Expression (1) is satisfied: ?0.5<f2/f1<0.5 (1).

Abstract: A finder includes, in order from an object side to an eye point side, an objective optical system that forms an intermediate image, and an ocular optical system that is provided for observation of the intermediate image. The intermediate image is positioned on the optical path between the objective optical system and the ocular optical system. The finder includes a plurality of reflecting surfaces for forming an erect image, and each of the objective optical system and the ocular optical system has at least one of the plurality of reflecting surfaces. The finder satisfies a conditional expression: 2<fo/fe<8 regarding a focal length fo of the objective optical system and a focal length fe of the ocular optical system.

Abstract: The imaging lens includes, successively in order from a position closest to an object side: a first lens group that remains stationary with respect to an image plane during focusing; and a focus lens group that moves along an optical axis during focusing. Assuming that a maximum image height is Ymax, and a focal length of the imaging lens is f, and a sum of a back focal length in terms of an air-equivalent distance and a distance on the optical axis from a lens surface closest to the object side to a lens surface closest to the image side is TL, the imaging lens satisfies Conditional Expressions (1) and (2). 0.1<Ymax/f<0.26??(1): 0.4<TL/f<1.

Abstract: Provided is an observation apparatus capable of adjusting visibility of an image and of an optical image of a subject in consideration of an intensity of ambient light in a case where the image is displayed by being superimposed on the optical image. The observation apparatus (30) includes an optical system (32), a display mechanism (34) that displays an image based on a signal generated by an imaging element (20), and a light shielding mechanism (36) of which a light shielding rate is variable, and the optical image has a first optical region (OP1) and a second optical region (OP2). The display mechanism (34) superimposes the image on the first optical region (OP1) to display both the image and the optical image in an observable manner by a user.

Abstract: The imaging lens includes, in order from an object side, a first lens group that has a refractive power, a second lens group that has a positive refractive power, and a third lens group that has a negative refractive power. During focusing, the second lens group moves. The second lens group includes a stop and at least three negative lenses. The imaging lens satisfies predetermined conditional expressions.

Abstract: Provided is a finder device capable of preventing dust on a display surface of a display element and reducing an influence of heat which is generated from the display element on an optical system. An EVF 1 includes: an optical system 20 that includes a display element 10, a first lens group G1 disposed in order from the display element 10 side, and a second lens group G2; a first holding frame 30 that holds the display element 10 and the first lens group G1 to seal a space between the display element 10 and the first lens group G1; a second holding frame that holds the second lens group G2; and a diopter adjustment unit 50 that adjusts a diopter by integrally moving the display element 10 and the first lens group G1 relative to the second lens group G2.

Abstract: An electronic view finder includes a display element that displays an image, and an eyepiece lens that is disposed on an eyepoint side of the display element and that is used for observing the image. The eyepiece lens consists of a first lens, a second lens having refractive power of a different sign from the first lens, and a third lens having positive refractive power in order from a display element side. Diopter is adjustable by moving at least one lens of the eyepiece lens. A television distortion of the image displayed by the display element varies depending on the diopter.

Abstract: An observation optical system includes a display element and an eyepiece lens arranged on an eyepoint side of the display element. The eyepiece lens includes at least one negative lens. In a case where a half value of a longest diameter of a display region in the display element is denoted by H, and a focal length of the eyepiece lens is denoted by f, the observation optical system satisfies a conditional expression represented by 0.35<H/f<0.6.

Abstract: The finder includes, in order from an object side to an eye point side, a negative objective lens group, and a positive eyepiece lens group. The eyepiece lens group consists of, in order from the object side to the eye point side, a negative first lens, a positive second lens, and a negative third lens. During diopter adjustment, only the second lens moves. The finder satisfies a conditional expression determined in advance.

Abstract: An observation optical system includes a display element and an eyepiece lens arranged on an eyepoint side of the display element. The eyepiece lens consists of a first lens having positive refractive power, a second lens having negative refractive power, and a rear side lens group including two or more lenses consecutively in order from a side closest to the display element to the eyepoint side. In a case where a half value of a longest diameter of a display region in the display element is denoted by H, and a focal length of the eyepiece lens is denoted by f, the observation optical system satisfies a conditional expression represented by 0.3<H/f<0.5.

Abstract: A finder optical system includes a display element and a diffractive optical element that is disposed on an eye point side of the display element so as to continue from the display element. The diffractive optical element includes a first base, a first layer that is laminated on the first base and includes a first diffractive optical surface on a surface thereof opposite to the first base, a second base, and a second layer that is laminated on the second base and includes a second diffractive optical surface on a surface thereof opposite to the second base. The first diffractive optical surface and the second diffractive optical surface are in close contact with each other.

Abstract: A finder display unit displays a live view image based on a captured image generated by an imaging unit. A digital signal processing unit detects a movement vector between frames in the live view image for a predetermined portion in the captured image. A digital signal processing unit changes a display range of the live view image on the finder display unit based on the detected movement vector of a peripheral portion in the captured image.

Abstract: An imaging lens consisting of, in order from an object side to an image side: a first lens group; a second lens group that has a positive refractive power; and a third lens group that has a negative refractive power, wherein the first lens group includes, successively in order from a position closest to the object side to the image side, two negative lenses and a positive lens, the second lens group includes a positive lens and a negative lens, during focusing from an object at infinity to a closest object, the first lens group remains stationary with respect to an image plane, and the second lens group moves along an optical axis, and assuming that a focal length of the first lens group is f1, and a focal length of the second lens group is f2, Conditional Expression (1) is satisfied: ?0.5<f2/f1<0.5 (1).

Abstract: An observation optical system including: a display element; and an eyepiece lens disposed on an eye point side of the display element, wherein the eyepiece lens consists of, in order from a display element side toward the eye point side, a first lens having a positive refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power, and in a case where a longest diameter of a display area in the display element is H, and a focal length of the eyepiece lens is fA, a conditional expression (1) is satisfied: 0.7<H/fA<0.8 ??(1).

Abstract: The imaging lens consists of, in order from the object side, a positive first lens group, a stop, a positive second lens group, and a negative third lens group. Lenses arranged first and second from the object side are both negative single lenses having convex surfaces toward the object side. The second lens group includes a cemented lens in which a negative lens and a positive lens are cemented. During focusing, only the second lens group moves. Assuming that focal lengths of the first lens group and the second lens group are f1 and f2, respectively, the imaging lens satisfies 0.7<f1/f2<2.

Abstract: The finder includes, in order from an object side to an eye point side, a negative objective lens group, and a positive eyepiece lens group. The eyepiece lens group consists of, in order from the object side to the eye point side, a negative first lens, a positive second lens, and a negative third lens. During diopter adjustment, only the second lens moves. The finder satisfies a conditional expression determined in advance.

Abstract: The imaging lens includes at least one negative lens that satisfies predetermined Conditional Expressions (1) to (3) indicating conditions in which dispersion is relatively low and refractive index is high while having a negative rate of change of the refractive index. A positive lens having a largest Abbe number at the d line among positive lenses included in the imaging lens satisfies predetermined Conditional Expressions (4) and (5).

Abstract: The imaging lens consists of, in order from an object side, a first lens group having a positive refractive power, a second lens group having a positive refractive power, a stop, a third lens group having a negative refractive power, and a fourth lens group. The first lens group has, in order from the object side, a positive single lens, and two or more cemented lenses. The second lens group consists of a positive lens and a negative lens. During image blur correction, only the third lens group moves. A conditional expression relating to the back focal length Bf and the lens system total length TTL is satisfied: 2<TTL/Bf<3.6.