Abstract: A zoom camera comprising an optical path folding element (OPFE) for folding the light from a first optical path to a second optical path, a first lens having a first optical axis and a first effective focal length EFLL1, the first optical axis being along the second optical path, a collimating lens having a second optical axis, and an image sensor located on the second optical path, wherein the collimating lens is movable between at least a first state and a second state, wherein in the first state the collimating lens is positioned in the second optical path between the OPFE and the first lens such that light entering the first lens arrives only from the image side of the collimating lens, and wherein in the second state the collimating lens is positioned outside the first optical path such that light entering the first lens does not arrive from the image side of the collimating lens.

Abstract: A zoom camera comprising an optical path folding element (OPFE) for folding the light from a first optical path to a second optical path, a first lens having a first optical axis and a first effective focal length EFLL1, the first optical axis being along the second optical path, a collimating lens having a second optical axis, and an image sensor located on the second optical path, wherein the collimating lens is movable between at least a first state and a second state, wherein in the first state the collimating lens is positioned in the second optical path between the OPFE and the first lens such that light entering the first lens arrives only from the image side of the collimating lens, and wherein in the second state the collimating lens is positioned outside the first optical path such that light entering the first lens does not arrive from the image side of the collimating lens.

Abstract: An optical device with switchable multiple lenses can be mounted on an electronic device through a connecting module, and provides finely-adjusted alignment with an image capturing lens in any position, and provides a zoom or wide-angle lens for the user to change the focal length and view field of the image. A light-filling/polarizing regulation module to fill light and eliminate unnecessary reflected light to avoid marginal diminishing effect of the image. The optical device includes a viewing device, a connecting module and a light-filling/polarizing regulation module, wherein the viewing device includes a lens module located in the housing and having at least two lenses through which an image captured by the image capturing lens is magnified. At least two lenses has the same lens power, or at least two lenses of different magnifications can be used with the switchable lens seat to obtain the effects of switching different lenses.

Abstract: A rear converter lens consists of, in order from the object side, a positive first lens group, a negative second lens group, and a positive third lens group. The first lens group consists of a cemented lens in which a negative lens concave toward the image side and a positive lens convex toward the object side are cemented, the second lens group consists of a cemented lens in which a negative lens concave toward the image side, a positive lens convex toward both sides, and a negative lens concave toward the object side are cemented, and the third lens group consists of, in order from the object side, a third lens group-first lens that is a positive lens convex toward the object side and a third lens group-second lens that is a negative lens.

Abstract: A camera and a terminal including the same are disclosed. The camera according to an embodiment of the present invention includes: a first prism apparatus to reflect a first input light input in a first direction to a second direction; a second prism apparatus to reflect a second input light input in the first direction to the second direction, and output the reflected second input light to the first prism apparatus; a lens apparatus to receive the first input light from the first prism apparatus or the second input light from the second prism apparatus; and an image sensor to generate an image signal based on the first input light or the second input. Accordingly, it is possible to implement a slim camera that can use a single image sensor with respect to a plurality of cameras at the time of front photographing or rear photographing.

Abstract: One or more colored films selectively change the color of the displayed light from one or more mobile devices to enable crowd participation is a multi-colored light show at public gatherings. The ability to change the color of a mobile device flash may also be useful for providing identification at a distance in low light conditions.

Abstract: In a converter device that is attached between a lens device, which is attachable to and detachable from an image capturing apparatus, and the image capturing apparatus, and that has a reimaging optical system configured to reimage a primary image formed by the lens device on an image plane as a secondary image, the imaging magnification of the reimaging optical system and imaging positions of a primary image and a secondary image are appropriately set.

Abstract: A zoom lens having unpowered optical elements changeably inserted between conventional powered optical zoom elements enables ultra-fast and mechanically stable stepped changes in zoom state.

Abstract: The present invention discloses a multi-optical shooting system, including an optical lens, where a spectroscopical module that can split a light wave transmitted from the optical lens into several light waves in different wavelength ranges is disposed on an imaging side of the optical lens; the shooting system further includes at least two photosensitive chips configured to receive light signals that are obtained by means of splitting by the spectroscopical module; the shooting system further includes an image processing system that can integrate and output light waves received by the photosensitive chips; and the spectroscopical module includes at least one spectroscopical component, where the spectroscopical component is a prism, a thin film, or a plane mirror. In the present invention, high definition of a shot image is implemented, image color restoration is good, and clear imaging can be implemented even in low illuminancy.

Abstract: An optical image capturing system includes, along the optical axis in order from an object side to an image side, a first lens, a second lens, a third lens, a fourth lens, a fifth lens, a sixth lens, and a seventh lens. At least one lens among the first to the sixth lenses has positive refractive force. The seventh lens can have negative refractive force, wherein both surfaces thereof are aspheric, and at least one surface thereof has an inflection point. The lenses in the optical image capturing system which have refractive power include the first to the seventh lenses. The optical image capturing system can increase aperture value and improve the imagining quality for use in compact cameras.

Abstract: An imaging lens is constituted by, in order from the object side to the image side: a positive first lens group; a stop; a negative second lens group; and a positive third lens group. Only the second lens group moves in the direction of the optical axis to perform focusing operations. The second lens group is constituted by one or two positive lenses and one negative lens. The third lens group is constituted by, in order from the object side to the image side, two or three positive lenses and one negative lens.

Abstract: A teleconverter lens consists essentially of, in order from the object side: a front group having a positive refractive power; and a rear group having a negative refractive power, wherein the front group and the rear group are separated from each other by the widest air space, the front group consists essentially of one positive lens having a convex surface toward the object side, and the rear group includes, in order from the object side, at least one negative lens having a concave surface toward the image side, and at least one positive lens having a convex surface toward the object side.

Abstract: An imaging lens consists of, disposed in order from the object side, a front group, a stop, and a rear group, wherein the front group includes, in order from the most-object side, a positive first lens, a negative second lens, and a negative third lens which are adjacently disposed, the rear group consists of two sets of cemented lenses having positive refractive powers and a positive single lens, the object-side cemented lens is formed by cementing, in order form the object side, a positive lens with a convex surface toward the image side and a negative meniscus lens together, the image-side cemented lens is formed by cementing, in order from the object side, a negative meniscus lens with a concave surface toward the image side and a positive lens together, and the image-side cemented lens is disposed at the most-image side of the rear group.

Abstract: An imaging lens consists of, in order from the object side, a front group, a stop, and a rear group, wherein the front group includes, in order from the most-object side, a positive first lens, a negative second lens, a negative third lens which are adjacently disposed, and further includes a final lens of the front group adjacent to the stop, with the surface toward the stop being convex toward the image side, the rear group includes, in order from the image side, two sets of cemented lenses having positive refractive powers, which are adjacently disposed, the object-side cemented lens of the two sets of cemented lenses is formed by cementing a positive lens and a negative meniscus lens together, and the image-side cemented lens is formed by cementing a negative meniscus lens and a positive lens together.

Abstract: A teleconverter includes a master lens apparatus-side mount on which a master lens apparatus is mounted, a camera body-side mount on which a camera body is mounted, and a converter lens unit that has a negative refracting power for mounting the master lens apparatus thereon to obtain a lens system having a focal length longer than that of the master lens apparatus, the converter lens unit including a first lens group on the master lens apparatus side and a second lens group on the camera body side with an on longest air separation interposed between them, the first lens group has positive refracting power, and the second lens group has negative refracting power, with satisfaction of the following condition (1): ?1.53<f1/f<?0.66??(1) where f is the focal length of a whole system of the converter lens unit, and f1 is the focal length of the first lens group.

Abstract: An imaging lens includes a first lens having positive refractive power; a second lens having negative refractive power; a third lens having positive refractive power; a fourth lens having at least one aspheric surface; a fifth lens having at least one aspheric surface; a sixth lens having two aspheric surfaces; and a seventh lens having two aspheric surfaces, arranged in this order from an object side to an image plane side. The first lens is formed in a shape so that both surfaces are convex near an optical axis thereof. The fourth lens is formed in a meniscus shape so that a surface thereof on the object side is concave near the optical axis. The seventh lens is formed in a shape so that a surface thereof on the image plane side is concave near the optical axis.

Abstract: In one embodiment of the present invention, a method for processing an image in an electronic device having a plurality of optical lenses is provided. The method for processing an image may comprise the steps of: obtaining a first image according to a first mode by means of a first optical lens; obtaining a second image simultaneously with or after the obtaining of the first image according to a second mode by means of a second optical lens; and processing and storing the first image obtained according to the first mode and the second image obtained according to the second mode. Here, the first and second modes are different from each other and may vary.

Abstract: An optical system (OL) includes a magnification conversion optical unit (EXT) configured to be insertable and removable at a position between an aperture stop (SP) and an image plane (IP) of the optical system in order to change a focal length of the optical system, a total lens length of the optical system is constant before and after insertion of the magnification conversion optical unit, and a length Lp on an optical axis from the aperture stop to the image plane of the optical system, and a length Le on the optical axis from a lens surface closest to an object side of the magnification conversion optical unit to the image plane when the magnification conversion optical unit is inserted are appropriately set.

Abstract: An optical sighting device and a method of providing magnification in the optical sighting device are disclosed. In one example, the optical sighting device comprises a first telescope including a first focal plane, a second telescope, comprising a first variable power lens group, a second variable power lens group, and a second focal plane positioned between the first and second variable power lens groups, and a rotary optical tumbler comprised of a Galilean telescope configured to rotate into and out of a optical path that extends through the first telescope, the Galilean telescope and the second telescope, the rotation being about an axis disposed relative to the optical path.

Abstract: A lens device (3A) is connected to a lens device (3B) to be used in association therewith. The lens device includes a setting unit (25) setting the lens device (3A) as a master, and a control unit (22) driving a control object of the lens device (3A) in response to a control signal input to the lens device (3A) and transmitting the control signal for driving the control object of the lens device (3B) to the lens device (3B) with respect to the control object for which the master has been set by the setting unit. The control unit transmits a mode switching signal which instructs to switch to a slave operating mode that is operated in response to the control signal input from the lens device (3A), to the lens device (3B), with respect to the control object for which the master has been set.

Abstract: Provided is a zoom lens including a focus lens portion, a zoom portion, an aperture stop, and a relay portion that does not move for zooming but comprises a negative fourth-first unit, a fourth-second unit interchangeable for an optical path, a positive fourth-third unit, and a fourth-fourth unit insertable for the optical path for shifting a focal length range of an entire system to a long focal length side after removing the fourth-second unit from the optical path, and a distance on an optical axis between the aperture stop and a last lens surface of the fourth-fourth unit in a state of inserting the fourth-fourth unit in the optical path, a distance on the optical axis between a first lens surface and the last lens surface of the fourth-fourth unit, and an aperture diameter in an opened state of the aperture stop satisfy a predetermined conditions.

Abstract: A tele-side converter lens including a first unit having a positive refractive power and a second unit having a negative refractive power, in which: the first unit includes one or two positive lenses; the second unit includes one negative lens and one or two positive lenses; and average Abbe constant and partial dispersion ratio of materials of positive lenses constituting the first unit, average Abbe constant and partial dispersion ratio of materials of positive lenses constituting the second unit, an Abbe constant and a partial dispersion ratio of materials of the negative lenses constituting the second unit, combined Abbe constants of materials of the lenses constituting the respective first and second units, focal lengths of the first and second units, a refractive index of a material of a positive lens disposed closest to the object side, and a magnification of the tele-side converter lens are appropriately set, respectively.

Abstract: Provided is a camera apparatus including a lens apparatus which is attachable thereto and detachable therefrom, the camera apparatus including: an optical system; and an optical element which is insertable to and removable from an optical path of the optical system, in which: the optical element includes a surface having positive refractive power; and the optical system includes a surface having negative refractive power.

Abstract: Provided is a zoom lens including a focus lens portion, a zoom portion, an aperture stop, and a relay portion that does not move for zooming but comprises a negative fourth-first unit, a fourth-second unit interchangeable for an optical path, a positive fourth-third unit, and a fourth-fourth unit inserteable for the optical path for shifting a focal length range of an entire system to a long focal length side after removing the fourth-second unit from the optical path, and a distance on an optical axis between the aperture stop and a last lens surface of the fourth-fourth unit in a state of inserting the fourth-fourth unit in the optical path, a distance on the optical axis between a first lens surface and the last lens surface of the fourth-fourth unit, and an aperture diameter in an opened state of the aperture stop satisfy a predetermined conditions.

Abstract: Apparatus, methods, and systems provide emitting and negatively-refractive focusing of electromagnetic energy. In some approaches the negatively-refractive focusing includes negatively-refractive focusing from an interior field region with an axial magnification substantially less than one. In some approaches the negatively-refractive focusing includes negatively-refractive focusing with a transformation medium, where the transformation medium may include an artificially-structured material such as a metamaterial.

Abstract: The disclosed internal focusing large-aperture medium telephoto lens has as lens groups a positive first lens group, a positive second lens group, and a third lens group, in that order from the object side. When focusing on nearby objects, the first lens group and the third lens group have a fixed position relative to the image surface, and the second lens group displaces toward the object side. The second lens group has only one negative lens, and, in order from the object side, has at least a positive lens, a negative lens, and a positive lens. The following expression is fulfilled: ?0.5<(R1+R2)(R1?R2)<?0.1 (wherein, R1: radius of curvature of the object side surface of the negative lens in the second lens group; R2: radius of curvature of the image side surface of the negative lens in the second lens group).

Abstract: Provided is an endoscope objective optical system that allows close-up observation while ensuring sufficient image brightness. Provided is an endoscope objective optical system consisting of a front group, an aperture stop, and a back group disposed in order from an object side; and a meniscus lens that can be inserted in and removed from an optical path between the aperture stop and the front group or the back group, with a convex surface thereof facing the aperture stop side.

Abstract: The image projection apparatus includes a light modulating element modulating light according to an image signal, a correcting part performing correction processing on the image signal to decrease geometric distortion in a projection image by using correction data, a memory storing first correction data corresponding to interchangeable optical units, and a controller acquiring identification information of the interchangeable optical unit attached to the apparatus, reading the first correction data corresponding to the acquired identification information from the memory, and setting the read first correction data as the correction data for the correction processing. The controller acquires, when no first correction data corresponding to the acquired identification information is stored in the memory, second correction data stored in a memory in the attached interchangeable optical unit, and sets the acquired second correction data as the correction data for the correction processing.

Abstract: Provided is an adapter optical system attachable between an image pickup lens and a camera body, the adapter optical system including, in order from an object side: a first optical unit having negative refractive power; a second optical unit that is insertable in and removable from an optical path; and a third optical unit having positive refractive power, in which the following expression is satisfied: 0.03<|?2|<0.50, where ?a2 represents an incident converted inclination angle obtained by normalizing an incident inclination angle of an axial beam entering the second optical unit inserted in an optical path with an exit inclination angle of an axial paraxial ray emerging from a surface closest to an image plane side in the adapter optical system being set to one (1).

Abstract: A lens assembly for a smartphone and a method of use is disclosed. In a first aspect, a lens assembly comprises a rotatable wheel; wherein the wheel includes at least two lenses. The lens assembly includes a skin portion coupled to the rotatable wheel, wherein the skin portion is adjustable to cover a smartphone. The at least two lenses of the wheel are positioned such that when one of the lens of the assembly is properly positioned it covers the lens of a camera on the smartphone. In a second aspect the method comprises providing a lens assembly over a camera lens of a smartphone chassis. The lens assembly includes a plurality of lenses that are rotatable. The method includes ensuring that the center of the smartphone lens is congruent with the center of the selected lens of the plurality of lens by referencing at least two surfaces of the smartphone chassis.

Abstract: A changer includes an axis of rotation for at least one optical element for at least one optical path comprising an optical axis. The changer inserts the optical element into the optical path by a rotary motion or removes it from the optical path. The optical path is one of at least two spatially connected optical paths and the axis of rotation of the changer is located between two parallel lines. The parallel lines run in a plane through the interfaces of the optical axes of the optical paths with one plane, which intersects the optical axes under the same angles and is perpendicular to the plane, which is spanned by the optical axes. The parallel lines are perpendicular to the connecting line between the two interfaces of the optical axes of the optical paths with the one plane, which intersects the optical axes under the same angles.

Abstract: Introduced is an optical arrangement for varying an imaging ratio and/or a refractive power including at least one optical axis, having at least two optical elements, which can be pivoted into and/or pivoted to and/or switched into and/or switched to the optical path, which encompass in each case a refractive power and an optical axis and the optical axes of which can in each case be made to be substantially congruent with the optical axis of the arrangement or are substantially congruent with the optical axis of the arrangement. The optical path between the optical elements, which can be pivoted into and/or pivoted to and/or switched into and/or switched to, undergoes at least one change in direction and/or vergence.

Abstract: A wide-angle converter lens capable of being detachably mounted on an enlargement side of an imaging lens includes a first optical element, at least one optical element having negative refractive power, and at least one optical element having positive refractive power, wherein, when an average value of relative partial dispersions of the first optical element and all optical elements of which the sign of refractive power is the same as that of the first optical element is denoted by ?gF_ave, a relative partial dispersion of the first optical element is denoted by ?gF, and an Abbe number of the first optical element is denoted by ?d, these numerical values satisfy appropriate relationships.

Abstract: A lens system and a photographing apparatus including the lens system are provided, the lens system including a first sub lens system that includes a plurality of lens groups, and a second sub lens system that includes a replacement lens group that replaces or is replaced by some of the plurality of lens groups.

Abstract: A teleconverter lens system is attachable to or detachable from an object side of a main lens system and facilitates performing telephotographing. A photographing apparatus includes the teleconverter lens system. The teleconverter lens system includes: a first lens having a negative refractive power; a second lens having a positive refractive power; a third lens having a negative refractive power; and a fourth lens having a positive refractive power, wherein the first, second, third, and fourth lenses are sequentially arranged from an object side to an image side of the teleconverter lens system. The first and second lenses are cemented together, and the second lens has a meniscus shape in which a convex surface is formed on the object side of the second lens.

Abstract: The invention relates to improving optical properties of optical instruments with variable magnification, such as zoom binoculars, reducing the weight thereof, and enabling the user to change magnifications quickly. The invention provides an optical instrument with a focal length-varying lens 4 disposed on the optical axis between an objective lens 7 and an eyepiece 3, further having an adjusting lens 5 for adjusting optical properties when the focal length-varying lens is in an area to provide high magnification. The adjusting lens is supported so that it is capable of moving between a location on the optical axis and a location off the path of light beams. Interlocked with a magnification-varying mechanism that controls the position of the focal length-varying lens, the adjusting lens is moved to the on-the-axis location when the focal length-varying lens is in an area to provide high magnification, and to the off-the-axis location when low magnification.

Abstract: A lens optical system includes a first optical system and a second optical system. The lens optical system includes at least one reflection member to selectively redirect optical paths of light representing objects from first and second directions toward a photographing device. The first optical system includes, in order from an object to the photographing device along the optical axis, a first lens group including a first reflection member, a second lens group having a negative refractive power, a third lens group having a positive refractive power, and a fourth lens group having a positive refractive power. The second optical system shares at least one optical element with the first optical system.

Abstract: An optical system including a first lens group configured to correct for lateral chromatic aberration, and an adjacent second lens group configured to correct for axial chromatic aberration. The optical system includes a detector disposed behind the second lens group, a mechanism for switching the optical system between a narrow field of view configuration and a wide field of view configuration, and a ray path steering system including a pair of counter-rotating grisms disposed in front of the first lens group. The optical system also includes a stabilization system configured to suppress image jitter and including a mechanism for decentering at least one lens in the first or second lens groups orthogonal to an optical axis of the optical system. A pupil of the optical system is located external to the first and second lens groups for location of a cold shield within a cryo-vac Dewar enclosing the detector.

Abstract: A zoom lens system including at least one lens group that is positioned to be movable along an optical axis of image light for photographing; and a movable frame including a plurality of selection lens groups, the movable frame being movable between a photographing position and a storage position, wherein the photographing position is a position in which one of the selection lens groups is selectively positioned on the optical axis, and the storage position is a position in which all of the selection lens groups are outside the optical axis, and the movable frame including a storage portion that houses at least a portion of the at least one lens group when the movable frame is moved to the storage position.

Abstract: An axis adjustment device, which may adjust an optical axis mismatch of an optical device at a high precision, and may perform an axis adjustment operation, includes a holding member to hold an optical device, a support member to support the holding member so that the holding member moves within a facing surface, a first rotating member to hold the holding member and rotatably supported around a first point S1 formed at a surface facing the support member, and a second rotating member to hold the holding member and to be rotatably supported around a second point formed at the surface facing the support member. The holding member moves within the surface facing the support member due to a rotation of one of the first and second rotating members and in order to adjust a relative position in a direction orthogonal to an optical axis of the optical device.

Abstract: A composition comprising particles for damping vibrations performed by cooperating surfaces of a mirror adjustment mechanism relative to each other. The cooperating surfaces adjustably connect a mirror holder for supporting the mirror element with a base plate that can be fixedly mounted to a motor vehicle. In an embodiment, the particles positioned close to one of the surfaces are arranged to move to a lesser extent relative to that surface upon a high-frequency pivoting of the cooperating surfaces than particles that are further removed from that surface. A method for assembling a mirror adjustment mechanism for adjusting a mirror element of a mirror unit of a motor vehicle mirror and an adjustment mechanism for adjusting a mirror element of a mirror unit are also disclosed.

Abstract: A lens driving-control device including a plurality of lens groups having variable magnification function, a plurality of lens driving devices each of which being configured to adjustably drive a driving speed of each of the plurality of lens groups, a control device configured to control each of the plurality of lens driving devices to adjust the driving speed of each of the plurality of lens groups, and a plurality of lens position-detecting devices each of which being configured to detect a position of each of the plurality of lens groups, when the plurality of lens driving devices drive the plurality of lens groups simultaneously, the control device being configured to control the lens driving devices to switch driving speeds of the plurality of lens groups to a driving speed of a lens group to be adjusted depending on a positional relationship among the plurality of lens groups, the positional relationship being detected by the lens position-detecting devices.

Abstract: A conversion lens which includes a pair of transparent members is provided. At least one of the transparent members is formed of a deformable film; a connecting member for connecting the pair of transparent members so as to form a sealed space sandwiched between the pair of transparent members; a liquid filled in the sealed space; and a curvature changing mechanism for changing the curvature of the deformable film by moving the liquid filled in the sealed space. A conversion lens system and an imaging device, provided with the conversion lens are also provided.

Abstract: A light modulation panel is inserted into an optical path of an imaging lens composed of an image-forming optical system to make the imaging lens function as a depth-of-field-extended optical system. The light modulation panel has power that makes a peak position of defocus MTF when the imaging lens is used alone to function as the image-forming optical system and a peak position of defocus MTF when the imaging lens functions as the depth-of-field-extended optical system by insertion of the light modulation panel into the optical path of the imaging lens coincide with each other.

Abstract: Provided is a zoom lens including a focus lens portion, a zoom portion, an aperture stop, and a relay portion that does not move for zooming but comprises a negative fourth-first unit, a fourth-second unit interchangeable for an optical path, a positive fourth-third unit, and a fourth-fourth unit inserteable for the optical path for shifting a focal length range of an entire system to a long focal length side after removing the fourth-second unit from the optical path, and a distance on an optical axis between the aperture stop and a last lens surface of the fourth-fourth unit in a state of inserting the fourth-fourth unit in the optical path, a distance on the optical axis between a first lens surface and the last lens surface of the fourth-fourth unit, and an aperture diameter in an opened state of the aperture stop satisfy a predetermined conditions.

Abstract: Introduced is an optical arrangement for varying an imaging ratio and/or a refractive power including at least one optical axis, having at least two optical elements, which can be pivoted into and/or pivoted to and/or switched into and/or switched to the optical path, which encompass in each case a refractive power and an optical axis and the optical axes of which can in each case be made to be substantially congruent with the optical axis of the arrangement or are substantially congruent with the optical axis of the arrangement. The optical path between the optical elements, which can be pivoted into and/or pivoted to and/or switched into and/or switched to, undergoes at least one change in direction and/or vergence.

Abstract: A MEMS-based display device is described, wherein an array of interferometric modulators are configured to reflect light through a transparent substrate. The transparent substrate is sealed to a backplate and the backplate may contain electronic circuitry fabricated on the backplane. The electronic circuitry is placed in electrical communication with the array of interferometric modulators and is configured to control the state of the array of interferometric modulators.

Abstract: A changer includes an axis of rotation for at least one optical element for at least one optical path comprising an optical axis. The changer inserts the optical element into the optical path by a rotary motion or removes it from the optical path. The optical path is one of at least two spatially connected optical paths and the axis of rotation of the changer is located between two parallel lines. The parallel lines run in a plane through the interfaces of the optical axes of the optical paths with one plane, which intersects the optical axes under the same angles and is perpendicular to the plane, which is spanned by the optical axes. The parallel lines are perpendicular to the connecting line between the two interfaces of the optical axes of the optical paths with the one plane, which intersects the optical axes under the same angles.

Abstract: To provide an aberration correction configuration that can realize both an aberration correction function for a long focus and an aberration correction function for a short focus. While having a conventional aberration correction apparatus configuration that has two rotationally symmetric lenses arranged between two multipole lenses, three rotationally symmetric lenses are disposed between an objective lens and a multipole lens instead of the conventional arrangement in which two rotationally symmetric lenses are disposed therebetween. When using the objective lens with a long focal length, aberrations are corrected using two rotationally symmetric lenses among three rotationally symmetric lenses disposed between the objective lens and the multipole lens. When using the objective lens with a short focal length, e.g.

Abstract: A rear attachment lens detachably attached to an image side of a main lens system to change a focal length of an entire system so as to become longer than a focal length of the main lens system includes one or more positive lenses GMp. One among the one or more positive lenses GMp is a positive lens P1. The Abbe number, a partial dispersion ratio, and a partial dispersion ratio difference of a material of the one or more positive lenses GMp and of the positive lens P1, and a focal length of the positive lens P1 are correctly defined so that chromatic aberrations are appropriately corrected, when predetermined conditions are satisfied.