Abstract: Provided is an imaging support device including an acquisition portion that acquires reversal information indicating that a revolution direction of an imaging apparatus that is caused to revolve about one axis out of a first axis and a second axis intersecting with the first axis as a central axis by a revolution mechanism enabling the imaging apparatus to revolve about each of the first axis and the second axis as the central axis is reversed, and a control portion that, in a case where the reversal information is acquired by the acquisition portion, performs a control of operating an adjustment portion capable of adjusting a position of a captured image obtained by imaging performed by the imaging apparatus.

Abstract: An aircraft window assembly (10) includes a first panel (12) having a first surface (14) and a second surface (16). In a first state in which there is no pressure difference between the first surface (14) and the second surface (16), the first panel (12) has a cross-sectional shape selected from planar, outwardly convex, or inwardly convex. In a second state in which there is a pressure difference between first surface (14) and the second surface (16), the first panel (12) has an outwardly convex cross-sectional shape.

Abstract: Various improvements to inflatable membranes for use in three-dimensional imaging of interior spaces are disclosed. These improvements include, among other things, equipping the inflatable membrane with desirable optical features, such as fiducials, optical coatings, etc., that can be used to improve data acquisition.

Abstract: To provide a sighting device for use in a security sensor system, in which device enables an operator, assigned to conduct a sighting work, to look into the sighting device from a proper direction. The sighting device includes an eyepiece lens provided with a microlens, an objective lens provided with a first marker encompassed within the field of view of the eyepiece lens, and a reflecting mirror disposed on an optical path between the eyepiece lens and the objective lens. The first marker is comprised of a circular contour line or a polygonal contour line and is so set that when a viewing axis offsets from a tolerance, the first marker is viewed with a part thereof dropped out having been offset from the field of view of the microlens.

Abstract: A camera viewfinder viewer accessory includes an elongated body portion having first and second ends and a longitudinal axis. A connector for mounting the body portion to a camera viewfinder is located on a side of the body portion and adjacent to the first end. The body portion longitudinal axis is generally parallel to the camera viewfinder in a mounted disposition. An end assembly is connected to the body portion second end and is rotatable about the body portion longitudinal axis. A viewer assembly is connected to a side of the end assembly and has a longitudinal axis generally perpendicular to the body portion longitudinal axis. The viewer assembly extends away from the end assembly and terminates at an eyepiece. The viewer accessory directs an image from the camera viewfinder into the viewer assembly, to be viewed through the eyepiece in any rotatable disposition of the end assembly.

Abstract: An imaging apparatus includes: optical finder means for introducing subject light having passed through an image capturing optical system onto a predetermined mirror at a first angle and guiding light reflected off the predetermined mirror to a finder window; a liquid crystal display disposed in an optical path of the subject light in the optical finder means; and illumination means for illuminating the liquid crystal display with light having a predetermined wavelength, wherein scattered light produced in the liquid crystal display illuminated with the light from the illumination means is incident on the predetermined mirror at a second angle, the finder window is disposed in a path of the scattered light reflected off the predetermined mirror, and the predetermined mirror has reflection characteristics in which spectral reflectance associated with the predetermined wavelength of the light incident at the second angle is lower than the spectral reflectance associated with the predetermined wavelength of the

Abstract: An adjustment device including an enhanced underwater viewfinder having, in use, a substantially watertight body and including a plurality of prisms within the body, at least one of the prisms being moveable by element of a control mechanism operable from a position exterior of the body.

Abstract: An imaging apparatus, includes a viewfinder optical system for guiding an observation light beam to a viewfinder window, the observation light beam being output from an imaging optical system and then reflected from a main reflective surface, an imaging element for generating an image signal in response to the reception of the observation light beam, an exposure control unit for performing exposure control of the imaging element in response to the image signal from the imaging element, and a light sensing detector, arranged in the vicinity of the imaging element, for measuring light. The exposure control unit determines an exposure control value in the exposure control in response to a light measurement value provided by the light sensing detector if a predetermined condition is satisfied.

Abstract: The invention provides a viewing optical system comprising: a screen on which an object image by a taking lens is formed, an image erection optical system for erecting the object image formed on the screen, and an eyepiece lens system of positive refracting power for guiding a light beam leaving the image erection optical system to the eyeball of a viewer, wherein: the image erection optical system comprises a plurality of reflecting surfaces, the eyepiece optical system comprises, in order from a screen side to an exit pupil side, a first lens element of negative refracting power, a second lens element convex on both the screen side and the exit pupil side, and a third lens element that is of negative refracting power and has a meniscus shape concave on the exit pupil side, and the third lens element satisfies the following condition (1): 0.13<DL3/fe<0.

Abstract: There is provided an imaging apparatus having a viewfinder optical system; a first image sensor; a photometric sensor; and optical path changing means. The viewfinder optical system has a first reflective surface that reflects a monitoring luminous flux, and the first reflective surface changes a reflection angle of the monitoring luminous flux. A change in a reflection angle of the first reflective surface causes a course of the monitoring luminous flux to be switched between a first optical path and a second optical path. In a case of second optical path, a travel direction is changed with the optical path changing means placed on the second optical path, causing a photometric processing to be performed using the first image sensor, while in a case of the first optical path, the photometric processing is performed using the photometric sensor.

Abstract: The invention concerns an optical system adapted to split an optical path from a taking optical system into a finder optical system, which has a camera-shake correction function best suited for the finder optical system, and so on. This optical system comprises a taking optical system and a finder optical system. The taking optical system comprises an optical path splitter means operable to split an optical path into the finder optical system, and the finder optical system includes a relay optical system RLS for re-forming a subject image once. Anti-shake is implemented by shifting an optical subsystem RL that forms a part of the finder optical system in a plane vertical to an optical axis.

Abstract: An eyepiece includes, in order from the object side, a first lens with positive power, a second lens with positive power, and a third lens with negative power. The first lens is a positive meniscus lens with a convex surface facing the object side, and the eyepiece fails to have a fourth lens. The eyepiece satisfies the following conditions: 0.6<f1/f<1.2 ?2.0<f1-2/f3<?1.0 ?0.45<f3/f<?0.25 where f1 is the focal length of the first lens; f1-2 is a combined focal length of the first and second lenses and is a focal length where a diopter is ?1 m?1 when the focal length of the eyepiece is changed; f3 is the focal length of the third lens; and f is the focal length of the entire system of the eyepiece and is a focal length where a diopter is ?1 m?1 when the focal length of the eyepiece is changed.

Abstract: The invention concerns an optical system adapted to split an optical path from a taking optical system into a finder optical system, which has a camera-shake correction function best suited for the finder optical system, and so on. This optical system comprises a taking optical system and a finder optical system. The taking optical system comprises an optical path splitter means operable to split an optical path into the finder optical system, and the finder optical system includes a relay optical system RLS for re-forming a subject image once. Anti-shake is implemented by shifting an optical subsystem RL that forms a part of the finder optical system in a plane vertical to an optical axis.

Abstract: An in-finder indicator for a single-lens reflex camera comprises an eyepiece lens, a reflecting mirror for reflecting a beam of light from a subject, a screen having a screen surface which is subjected to surface treatment to form prisms for presenting a superimposed indication and which forms an image of the subject based on the light beam reflected by the reflecting mirror, a dach mirror having a pair of mirror surfaces for reflecting the light beam from the screen, a reflecting surface for reflecting the light beam reflected by the dach mirror surfaces and introducing the light beam to the eyepiece lens, and an illumination member disposed in a laterally-offset space between the dach mirror surfaces and the screen and introducing an illumination beam to enter the screen surface laterally of the image formed on the screen surface.

Abstract: According to the present invention, light from a taking lens is reflected by a quick return mirror in a lateral direction of a body unit. Then, after passing through a screen, the light is reflected toward an upper side of the body unit by a second mirror except part of the light. The light reflected by the second mirror is reflected by a third mirror in a direction opposite to a direction in which the light is reflected by the quick return mirror, and is further reflected by a fourth mirror toward an eyepiece located on a back side of the body unit. Part of the light which passing though the screen is taken by an AF sensor unit provided in rear of the second mirror, and an image formation position of an optical image is detected.

Abstract: An eyepiece includes, in order from the object side, a first lens with positive power, a second lens with positive power, and a third lens with negative power. The first lens is a positive meniscus lens with a convex surface facing the object side, and the eyepiece fails to have a fourth lens. The eyepiece satisfies the following conditions: 0.6<f1/f<1.2 ?2.0<f1-2/f3<?1.0 ?0.45<f3/f<?0.25 where f1 is the focal length of the first lens; f1-2 is a combined focal length of the first and second lenses and is a focal length where a diopter is ?1 m?1 when the focal length of the eyepiece is changed; f3 is the focal length of the third lens; and f is the focal length of the entire system of the eyepiece and is a focal length where a diopter is ?1 m?1 when the focal length of the eyepiece is changed.

Abstract: A camera according to the present invention includes a picture-taking lens unit including a picture-taking optical system having a bending optical system which optically bends incident light and an optical finder unit including a finder optical system having a bending optical system which optically bends incident light. A pre-bending optical system and a post-bending optical system in the bending optical system of the optical finder unit are arranged adjacent to a pre-bending optical system and a post-bending optical system in the bending optical system of the picture-taking lens unit, respectively. The body of the camera is therefore decreased in size.

Abstract: A light-projecting device comprises an ocular optical system facing an emergent opening of a hollow pentagonal mirror. A superimpose-plate is provided in an incident opening of the hollow pentagonal mirror so that a subject image obtained through a photographing optical system is formed. The superimpose-plate is put on a focusing glass. A mark, indicated in a picture plane of the view finder, is formed on the superimpose-plate. A light source radiates an illumination light beam. A light-projecting prism reflects the illumination light beam toward the emergent opening. The light-projecting prism has a light-projecting plane. The light-projecting plane is located below the optical axis of the ocular optical system.

Abstract: The present invention relates to a high-performance image-forming optical system made compact and thin by folding an optical path using reflecting surfaces arranged to minimize the number of reflections. A prism member 10 has a first entrance surface 11, first to fourth reflecting surfaces 12 to 15, and a first exit surface 16. An optical path incident on the first reflecting surface 12 and an optical path reflected from the second reflecting surface 13 form intersecting optical paths. An optical path incident on the third reflecting surface 14 and an optical path reflected from the fourth reflecting surface 15 form intersecting optical paths. At least either one of the first reflecting surface 12 and the second reflecting surface 13 and at least either one of the third reflecting surface 14 and the fourth reflecting surface 15 have a rotationally asymmetric curved surface configuration that gives a power to a light beam and corrects aberrations due to decentration.

Abstract: A digital single lens reflex camera includes a reflector located in a photographic light path to reflect object-carrying light transmitted through a photographic optical system toward a finder optical system. An image pickup device is located at the imaging plane of the photographic optical system. The object-carrying light in the photographic light path is reflected by the reflector in a direction substantially away from an eyepiece optical system of the finder optical system. A reflection light path is formed in the vicinity of the photographic optical system and is provided with a plurality of reflection surfaces to make the light reflected by the reflector in the photographic light path incident on the eyepiece optical system. Furthermore, a relay optical system is located in the reflection light path to relay an image formed on a primary imaging plane, which is optically equivalent to an image pickup surface of the image pickup device, to the eyepiece optical system.

Abstract: A camera is provided that includes a camera housing and a TFT panel, which permits verification of a formed image, located on the back of the camera housing. A strobe unit and an electronic viewfinder unit are located in the upper part of the camera housing. The electronic viewfinder unit has a unit body including: a TFT panel permitting viewing of an object image; an eyepiece opposed to the back of the camera housing and used to view the object image displayed on the TFT panel; and a prism serving as an optical path conversion member that bends by a predetermined angle light emitted from an object image displayed on the TFT panel so as to route the light to the eyepiece, and adjoining the TFT panel and the eyepiece.

Abstract: An optical and electronic viewer of a camera has a body having entrance and exit openings and entrance and exit tunnels extending inward from respective openings. The body has a cross tunnel connecting the entrance and exit tunnels. An eyepiece is mounted at the exit opening and defines and eyepiece axis. An objective lens is mounted at the entrance opening and defines an objective axis. An electronic imager is disposed within the body, in optical alignment with the objective lens. A microdisplay is mounted in the exit tunnel interior to the eyepiece. First and second reflectors are disposed in the cross tunnel. The reflectors are aligned and are each movable, within the cross tunnel, between an optical-viewing position and a non-viewing position. The first reflector is aligned with the objective axis and the second reflector is aligned with the eyepiece axis in optical-viewing position. The reflectors are spaced from the axes and each other in non-viewing position.

Abstract: In an electronic image pickup apparatus, a beam splitter and an image pickup element are incorporated into an optical finder unit together with optical parts used for an optical finder. The optical finder unit includes a finder case for receiving the optical parts used for the optical finder and a holding member for holding the beam splitter and the image pickup element. The image pickup element has an image pickup surface which is inclined to the light beams incident upon the beam splitter. The light beam incident upon the image pickup element is reflected twice in the beam splitter, while the light beam incident upon the optical finder penetrates the beam splitter without being reflected.

Abstract: A compact finder with excellent optical performance, and a camera including the finder are disclosed. The finder of the present invention includes an objective optical system, and an eyepiece optical system. The objective optical system includes, from an object side to an image side, a first lens unit having positive power, a second lens unit having negative power, a third lens unit having positive power, and a fourth lens unit having positive power. During zooming from a wide-angle end to a telephoto end, the second lens unit is moved toward the image side, the third lens unit is moved toward the object side, and the fourth lens unit is moved such that an air space between the fourth lens unit and the third lens unit is changed. The camera of the present invention includes a photo-taking optical system, and the finder of the present invention whose optical axis is different from an optical axis of the photo-taking optical system.

Abstract: A camera has a rangefinder device having an optical system constituted by a plurality of optical elements and a diopter adjustment mechanism capable of adjusting the observation diopter of the rangefinder device by operation by the user from outside the camera. In addition, there are provided an operating member that operates the diopter adjustment mechanism and an adjustment mechanism that effects adjustment such that the observation diopter of the rangefinder device is at a predetermined value when the operating member is in a prescribed position. By this means, a camera having a diopter adjustment mechanism whereby the relative positional relationship of the operating member and driven member can always be ensured such that the observation diopter gets equal to the predetermined observation diopter that is to be set when the operating member is arranged in the prescribed position. This can be realized by a straightforward construction.

Abstract: A single-lens reflex camera provided with an eyepiece includes a screen on which an image of an object is projected, a plurality of reflecting surfaces for erecting the image projected on the screen, and an eyepiece with positive refracting power for observing the image. In this case, the eyepiece has, in order from the object side, a first lens component with positive refracting power, a second lens component with positive refracting power, and a third lens component with negative refracting power and satisfies the following conditions: 0.15<tan S<0.35 2.00<fb/Y<5.00 −0.67<f3/f<−0.

Abstract: A camera including a photographing optical system and a finder optical system, includes an objective optical system and an ocular optical system, the optical axes thereof being parallel with each other; a reflection surface which reflects a light bundle in the vertical direction of the camera; a reflection surface which reflects the light bundle in the horizontal direction of the camera toward an light-emitting optical axis of the ocular optical system; and a reflection surface located on the light-emitting optical axis to make a connecting optical axis coincident with the light-emitting optical axis of the ocular optical system. The connecting optical axis is inclined with respect to the horizontal direction of the camera so that the optical axes of the objective optical system and the ocular optical system are close to each other with respect to the vertical direction of the camera.

Abstract: method and apparatus for aligning an optical element in an optical sub-assembly is provided. Pivoting fine tuning plates connected to the main body of the sub-assembly are used to set the height and angle of the optical element. The optical element is connected on a pin through the optical element frame between two portions of the main body. Pivoting the fine tuning plate with a cam causes the optical element pin to cant, adjusting the position and/or angle of the optical element. In one embodiment of the present invention, a laser may be used to better align the optical element.

Abstract: A finder unit includes an objective optical system for forming a viewing image, an inverting optical system for making the viewing image formed by the objective optical system an erecting normal image, an eyepiece optical system for viewing the viewing image, a first optical component deployed closer to the objective optical system than the viewing image formation position, and a second optical component deployed closer to the eyepiece optical system than the viewing image formation position; and satisfies the condition 8<1000×(D1+D2)/f2(1/m) when the focal length of the eyepiece optical system is represented as f (mm), the distance from the viewing image formation position to the first optical component as D1 (mm), and the distance from the viewing image formation position to the second optical component as D2 (mm).

Abstract: A finder optical system for a single lens reflex camera is provided with a photographing optical system, a beam splitter for splitting light passed through the photographing optical system. First light deflected by the beam splitter forms a primary image at a position downstream from the beam splitter. Second light passed through the beam splitter is incident on a CCD. A relaying optical system is arranged on an optical path of the light deflected by the optical element to relay the primary image to form a secondary image. A reflection surface is arranged between the relaying optical system and an eyepiece optical system. The reflection surface deflects light, which is directed from the relaying optical system, toward the eyepiece optical system, to proceed in a direction parallel with an optical axis of the photographing optical system. The secondary image is formed between the reflection surface and the eyepiece optical system.

Abstract: The present invention concerns a camera incorporating a real-image finder, having a structure more compact than ever. The camera includes an objective optical system; an erect-image optical system, having a reflecting surface, to receive a light bundle passed through the objective optical system; and an ocular optical system to receive the light bundle reflected from the reflecting surface of the erect-image optical system. In the camera, a rear end of the reflecting surface is located at a backward position with respect to a film conveyance surface and outside the film conveyance surface, and, a front end of the reflecting surface is located at a forward position with respect to the film conveyance surface and inside the film conveyance surface.

Abstract: A camera including a liquid crystal display in which an image formed by a photographing lens system of the camera is indicated; an ocular viewing optical system which includes a half-mirror surface and an eyepiece lens system, the half-mirror surface reflecting the image of the liquid crystal display toward the eyepiece lens system, so that the reflected image can be viewed through the eyepiece lens system; and a direct viewing optical system for viewing the image of the liquid crystal display through the half-mirror surface.

Abstract: A viewfinder for a camera with an adjustable diopter includes an objective lens and an eyepiece lens each having an optical axis extending parallel to a longitudinal axis of the camera. Light rays from the objective lens are reflected by a mirror and directed in one direction parallel to a transverse axis of the camera onto a focusing screen to form an object image. A first triangular prism receives light rays from the object image and reflects and directs the received light rays in opposite direction parallel to the transverse axis. A second triangular prism receives light rays from the first prism and reflects and directs the received light rays in the direction parallel to the longitudinal axis and toward the eyepiece lens. The first prism is supported and guided for linear displacement along the transverse axis, while the second prism is fixed to the body frame of the camera.

Abstract: A finder unit includes an objective optical system for forming a viewing image, an inverting optical system for making the viewing image formed by the objective optical system an erecting normal image, an eyepiece optical system for viewing the viewing image, a first optical component deployed closer to the objective optical system than the viewing image formation position and a second optical component deployed closer to the eyepiece optical system than the viewing image formation position and satisfies the condition 8<1000×(D1+D2)/f2(1/m) when the focal length of the eyepiece optical system is represented as f (mm), the distance from the viewing image formation position to the first optical component as D1(mm), and the distance from the viewing image formation position to the second optical component as D2 (mm).

Abstract: A viewfinder optical system of a single-lens reflex camera has a photographic optical system and an image plane positioned on an optical axis of the photographic optical system. The system includes a first optical member positioned between the photographic optical system and the image plane, the first optical member bending the optical axis of the photographic optical system to define a viewfinder optical axis of the viewfinder optical system. A second optical member bends the viewfinder optical axis at least once to make the viewfinder optical axis that extends parallel to the optical axis of the photographic optical system. A third optical member, having substantially no optical power, is positioned on the viewfinder optical axis extending parallel to the optical axis of the photographic optical system. The third optical member is made of a transparent material having a refractive index higher than the refractive index of air.

Abstract: A view finder device has a Poro prism and a first optical system facing an emergent plane of the Poro prism. The first optical system is positioned beside the Poro prism and opposite to a recording medium passage through which an electro-developing recording medium is moved. A relay optical system is provided behind the recording medium passage, so that the eye point of the view finder is separated from the first optical system. A second optical system is provided behind the relay optical system, so that the image formed by the relay optical system is observed. Since the electro-developing recording medium can be moved between the first optical system and the relay optical system, the finder optical system can be disposed at a lower position.

Abstract: A real-image finder optical system including a positive objective optical system in which an image of an object, being upside down and reversed from left to right, is formed; an erecting optical system, having a plurality of reflection surfaces, in which the image formed by the objective optical system is erected to the same orientation as the object; and an eyepiece optical system through which the image erected by the erecting optical system is viewed. A shape of a finder field of view is a rectangle having major sides along the transverse direction in the finder field of view. Along the optical path on the side of the object with respect to the image formed by the objective optical system, at least three reflection surfaces of the erecting optical system are provided, and further, the most object-side reflection surface is positioned so that the optical axis is deflected in a direction along the major side of the rectangular finder field of view.

Abstract: A real image mode finder includes an objective optical system with a positive refracting power, an image erecting optical system with a roof reflecting section, a first planar reflecting section, and a second planar reflecting section, and an eyepiece optical system with a positive refracting power. The image erecting optical system is constructed so that the optical axis does not cross in this optical system and a ray of light from the objective optical system is introduced into the roof reflecting section, the first planar reflecting section, and the second planar reflecting section in this order. The real image mode finder also satisfies the following conditions: 49°<&ggr;<62.5° 20°<&agr;<30° where &ggr; is an angle of incidence of an axial ray of light on the second planar reflecting section and &agr; is an angle of incidence of the axial ray of light on the roof ridgeline of the roof reflecting section.

Abstract: A real image finder comprises an objective lens system including a convex lens and having a positive power as a whole, an erect image prism having four reflection surfaces and inverting an inverted image of an object formed through the objective lens system in horizontal and vertical directions, and an eyepiece having a positive power, wherein the erect image prism and the eyepiece lens is integrated by forming an eyepiece surface on the image side of the erect image prism. To provide a fixed magnification finder, the objective lens system consists of a single lens having a positive power and at least one aspherical surface. To provide a zoom finder, the objective lens system comprises a first lens with a negative power and a second lens with a positive power arranged in this order from the object side. The second lens is moved along the optical axis for zooming.

Abstract: A real image mode finder includes an objective optical system and an eyepiece optical system which has at least one reflecting surface. The objective optical system includes, in order from the object side, an objective unit, a first prism and a second prism. The first prism has an entrance surface which transmits a light beam emerging from the objective unit and a transmission surface which is optically inclined with respect to the entrance surface. The second prism has a reflecting surface, situated nearly opposite to the entrance surface of the first prism, for obliquely reflecting the light beam transmitted through the first prism toward the object side, a transmitting-reflecting surface located nearly parallel with the transmission surface of the first prism, at a minute distance away therefrom, to transmit the light transmitted through the first prism and to totally reflect the light from the reflecting surface, and an exit surface.

Abstract: A diopter adjustment lens is provided with a follower pin on the edge thereof, and is arranged inside a cylinder provided with a guide groove engaging with the follower pin. A diopter adjustment dial, which is integrated with a diopter adjustment ring, is rotatably fitted on the cylinder. The diopter adjustment ring is provided with a cam face, and the follower pin of the diopter adjustment lens is brought into contact with the cam face through the guide groove in the cylinder. Rotating the diopter adjustment dial moves the diopter adjustment lens forward and backward thereby adjusting the diopter of the finder unit.

Abstract: A viewfinder optical system for conducting light from an object to an observer includes a plurality of reflecting surfaces having optical powers. Optical paths of each ray of a light flux reflected successively by the plurality of reflecting surfaces intersect each other at least twice, and the light from the object forms an image at least twice when passing through the viewfinder optical system.

Abstract: The invention aims to provide binoculars suitable to be used in a theater or a sports stadium, which can provide a wide and bright field of view on one hand, and which are compact and lightweight with improved portability and maneuverability on the other hand. Inverse reflection of an image is achieved by providing optical systems of inverse reflection, each comprising a pair of specular reflectors opposed to each other on an object side and an eyepiece side, respectively, so that an optical axis of light exiting the optical system of inverse reflection on the eyepiece side extends in parallel with an optical axis of light entering the optical system of inverse reflection on the object side, and one or more object lens(es) is or are placed on one or more path(s) selected from optical paths of reflection from respective specular reflectors forming the optical systems of inverse reflection.

Abstract: Disclosed is a real image type finder optical system which is provided with an objective optical system having a positive power, an erecting optical system for erecting a reversed real image formed by the objective optical system, an eyepiece optical system for observing the real image formed by the objective optical system and erected by the erecting optical system, an information display element provided in the objective optical system, the information display element displaying information to be observed in a field of view of the finder optical system, and a partial mirror surface provided on an object side with respect to the information display element, the partial mirror allowing a part of light from the object to pass therethrough and reflecting light from the information display element towards the eyepiece optical system.

Abstract: A viewfinder device that includes a screen on which an image is projected, and an eyepiece lens through which the image is viewed. An optical member passes light beams from the screen to the eyepiece lens through an information display member, and a diffraction optical element diffracts light beams in the direction of the eyepiece lens so that diffracted light beams from the information display member are superposed over the viewed image.

Abstract: A viewfinder optical system directs a luminous flux emanating from an image plane to a pupil. The viewfinder optical system has an eyepiece optical system. The eyepiece optical system enlarges an image in order to be viewed by the pupil. The eyepiece optical system has a first lens unit, a second lens unit and a third lens unit. The first lens unit has at least one surface having a positive optical power. The second lens unit has at least one surface having a negative optical power. The third lens unit has a reflecting surface having a positive optical power.

Abstract: A real-image finder optical system having an objective optical system, an image-inverting optical system, and an ocular optical system, wherein a power is given to a reflecting surface of the image-inverting optical system that is closer to the observer side than an intermediate image, thereby achieving an increase in the finder magnification. The objective optical system has a plurality of lens units. When zooming from the wide-angle end to the telephoto end is performed, the spacing between the plurality of lens units is changed. The image-inverting optical system has a plurality of reflecting surfaces. Of the reflecting surfaces, at least one reflecting surface closer to the ocular optical system than the object image is formed from a curved reflecting surface that gives a power to a light beam. The image-inverting optical system has a rotationally asymmetric surface that corrects rotationally asymmetric decentration aberrations produced by the curved reflecting surface.

Abstract: A camera having a viewfinder for viewing a subject to be photographed, and a flash unit for illuminating the subject which is supported for movement between an operative position in which the flash unit faces the subject and a storage position in which the flash unit does not face the subject, is characterized in that the viewfinder has an image-reflecting mirror that is arranged on the flash unit for movement with the flash unit to reflect an image of the subject when said flash unit is moved from the storage position to the operative position.

Abstract: A real-image finder optical system is provided with an information display element located between an image plane of an objective optical system and a moving lens group of the objective optical system, and a partial mirror surface provided on an object side with respect to the information display element. The finder optical system includes the objective optical system having a positive power, an erecting optical system for erecting a reversed real image formed by the objective optical system, and an eyepiece optical system for observing the real image. Magnification of the finder optical system varies with the movement of at least one moving lens group of the objective lens system in a direction of an optical axis.

Abstract: An optical apparatus is provided with an eyepiece, a focusing screen onto which an image is projected, a reflecting device for reflecting the light from the focusing screen to thereby cause it to enter the eyepiece in order to show the image, an illuminating device for illuminating an eye, an imaging optical system for receiving the light from the eye through the eyepiece and a certain portion of the reflecting device, and forming the image of the eye by the light from the eye, and a photoelectric converter for receiving the image of the eye. The reflecting device comprises a hollow optical part, and the light from the eye passes through the hollow portion and the mirror portion of the optical part.