An imaging device is configured to include a finder and an eyecup unit. An eyecup is provided so as to surround an eyepiece window formed on a cover member. A base member holds the eyecup and the cover member. The eyecup is configured to include a curved and hollow eyepiece region, a first holding region comprising a first hole group, and a second holding region comprising a second hole group. The base member is configured to include a first protrusion group corresponding to the first hole group and a second protrusion group corresponding to the second hole group. The first hole group fits with the first projection group, and the second hole group fits with the second projection group.

Mobile electronic devices comprising a first camera with a first field of view FOV.sub.1, a second, Macro camera with a Macro field of view FOV.sub.M smaller than FOV.sub.1, and a device screen that includes a first screen section configured to display first image data from the first camera and a second screen section configured to display second image data from the Macro camera when both cameras are focused to a distance equal to or smaller than 30 cm.

An electronic apparatus according to the present invention is an electronic apparatus that is capable of executing eye proximity sensing to sense whether an eye is in proximity of an eyepiece, and line-of-sight detection to detect a line-of-sight of a user, including: a first light source configured to emit light for the eye proximity sensing; a second light source configured to emit light for the line-of-sight detection; an eye proximity sensing sensor configured to receive light for the eye proximity sensing; and a line-of-sight detecting sensor configured to receive light for the line-of-sight detection, wherein a first wavelength, which is a peak wavelength of the light emitted by the first light source, is different from a second wavelength, which is a peak wavelength of the light emitted by the second light source.

An imaging apparatus has: an imaging optical system; an imaging element configured to receive light transmitted through the imaging optical system to generate an electric signal; a main body; a display device provided on a back face of the main body and capable of displaying an image generated on the basis of the electric signal generated by the imaging element; and an electronic viewfinder provided inside the main body and capable of displaying the image generated on the basis of the electric signal generated by the imaging element, wherein an eyepiece part of the electronic viewfinder is provided to a transmissive region of the display device.

An imaging apparatus has: an imaging optical system; an imaging element configured to receive light transmitted through the imaging optical system to generate an electric signal; a main body; a display device provided on a back face of the main body and capable of displaying an image generated on the basis of the electric signal generated by the imaging element; and an electronic viewfinder provided inside the main body and capable of displaying the image generated on the basis of the electric signal generated by the imaging element, wherein an eyepiece part of the electronic viewfinder is provided to a transmissive region of the display device.

An imaging device includes a composite display device capable of switching between an electronic viewfinder function and a sighting device function. The composite display device includes an eye window and an object window, an organic EL panel that displays a sighting mark that is an indicator, and a photochromic mirror that is a reflective optical element for guiding the indicator to the eye window. A determination unit determines a subject, and a distance-measuring unit measures a distance to the subject. A body control unit controls the organic EL panel, and a photochromic mirror control unit controls a state and a shape of the photochromic mirror. The body control unit performs control for adjusting the projected position of the sighting mark on the basis of distance information of the subject.

An imaging device includes a composite display device capable of switching between an electronic viewfinder function and a sighting device function. The composite display device includes an eye window and an object window, an organic EL panel that displays a sighting mark that is an indicator, and a photochromic mirror that is a reflective optical element for guiding the indicator to the eye window. A determination unit determines a subject, and a distance-measuring unit measures a distance to the subject. A body control unit controls the organic EL panel, and a photochromic mirror control unit controls a state and a shape of the photochromic mirror. The body control unit performs control for adjusting the projected position of the sighting mark on the basis of distance information of the subject.

An observation device according to the present invention includes an image display element displaying an image, and a finder optical system used for observing the image displayed on an image display surface of the image display element. The finder optical system includes a positive first lens, a negative second lens, and a biconvex positive third lens arranged in this order from the image display surface side to the observation side. A focal length of the second lens, a focal length of the finder optical system, a curvature radius of a lens surface of the second lens on the image display surface side, a curvature radius of a lens surface of the second lens on the observation side, a diagonal length of the image display surface, and a curvature radius of a lens surface of the third lens on the image display surface side are appropriately set.

An observation device according to the present invention includes an image display element displaying an image, and a finder optical system used for observing the image displayed on an image display surface of the image display element. The finder optical system includes a positive first lens, a negative second lens, and a biconvex positive third lens arranged in this order from the image display surface side to the observation side. A focal length of the second lens, a focal length of the finder optical system, a curvature radius of a lens surface of the second lens on the image display surface side, a curvature radius of a lens surface of the second lens on the observation side, a diagonal length of the image display surface, and a curvature radius of a lens surface of the third lens on the image display surface side are appropriately set.

A viewfinder with which an observing or image-recording device, such as a spotting scope or image-recording apparatus, is intended to be equipped, the observing device being configured to produce an image of an observed scene. The viewfinder allows a first image, representative of the observed scene, and a second image, different from the first image, to be displayed, the first image and the second image being juxtaposed with respect to each other. The observing device includes a first optical system and a second optical system configured to propagate the first image and the second image towards the eye of a user, along two distinct axes of propagation, respectively. The optical systems are such that passage from observing one image to observing the other image is achieved through simple natural rotation of the eye.