Canon Kabushiki Kaisha

Other

Keiji Ohtaka

Yasuo Suda

Akira Ishizaki

Takeshi Koyama

Akira Akashi

Ichiro Ohnuki

Akira Hiramatsu

Kenji Suzuki

Terutake Kadohara

Hiroshi Ohmura

Keiji Ikemori

Kazuhiko Momoki

Hitoshi Onoda

Keiji Nagata

Kenichiro Yamashita

Takashi Suzuki

Hidemasa Mizutani

Kiyoshi Iizuka

Tokuichi Tsunekawa

Akihiko Nagano

Kazuki Konishi

Hidehiko Fukahori

Shigeo Yoshida

Kikuo Momiyama

Kazuo Fujibayashi

Toshiaki Sato

Tetsuo Yoshizawa

Hideo Ukuda

Keisuke Aoyama

Kazuhiko Arakawa

Yusuke Ohmura

Tohru Yamamoto

Akio Mihara

Hatsumi Ikari

Taichi Sugimoto

Hiromichi Yamashita

Kenji Ito

Masayuki Abe

Susumu Matsumura

Atsushi Okuyama

Masaki Higashihara

Takashi Sudo

Hirokazu Ichiki

The polarization beam splitter of the present invention includes a polarized beam splitting layer having a structure in which a plurality of gratings parallel to a first direction are periodically disposed in a second direction orthogonal to the first direction, and of light incident on the polarization beam splitter, light having a chiefly polarized component parallel to the first direction is transmitted therethrough, and light having a chiefly polarized component parallel to the second direction is reflected.

Polarization beam splitter and optical system using the same, and image displaying apparatus, using the same

A high performance polarization splitting element and an optical device using the polarization splitting element are provided. According to an embodiment of the present invention, the optical device includes a first periodic structure having a period shorter than a wavelength of used light, a second periodic structure which has a period shorter than the wavelength of the used light and in which a direction of the period is orthogonal to or substantially orthogonal to that of the first periodic structure, and a pair of optical elements disposed so as to sandwich the first periodic structure and the second periodic structure. The second periodic structure is adjacent to the first periodic structure. The first periodic structure and the second periodic structure transmit light having first polarization direction and reflect light having second polarization direction orthogonal to the first direction, and the second polarization direction is substantially parallel to one of the periodic direction of the first periodic structure and the periodic direction of the second periodic structure.

Polarization element and optical device using polarization element

A high performance polarization splitting element and an optical device using the polarization splitting element are provided. According to an embodiment of the present invention, the optical device includes a first periodic structure having a period shorter than a wavelength of used light, a second periodic structure which has a period shorter than the wavelength of the used light and in which a direction of the period is orthogonal to or substantially orthogonal to that of the first periodic structure, and a pair of optical elements disposed so as to sandwich the first periodic structure and the second periodic structure. The second periodic structure is adjacent to the first periodic structure. The first periodic structure and the second periodic structure transmit light having first polarization direction and reflect light having second polarization direction orthogonal to the first direction.

In a conventional polarization beam splitter, it has been difficult to improve the angle-dependence characteristic of polarized beam splitting efficiency even if the number of layers is increased. The polarization beam splitter of the present invention is a polarization beam splitter having a polarized beam splitting layer having structure in which a plurality of gratings parallel to a first direction are periodically disposed in a second direction orthogonal to the first direction, and of light incident on the polarization beam splitter, chiefly light of a polarized component parallel to the first direction is transmitted therethrough, and chiefly light of a polarized component parallel to the second direction is reflected.

A camera capable of automatically detecting a main object in a sensed image. A distance distribution generation unit discriminates a plurality of areas in the sensed image on the basis of a predetermined condition, and a main object area determination unit automatically determines the main object area out of the discriminated areas. If the determined main object area is different from the area where an operator intends to focus on and the operator wishes to change the main object area, a new main object area is selected in accordance with an instruction inputted from a main object area changing unit. Then, the camera focuses on the selected main object area.

Optical device and method for selecting object of focus

When light from a reflection image display element is incident on a polarization split surface at an angle other than 45&deg;, leakage light that decreases the contrast of an image is produced. In a projection image display apparatus which illuminates an image display element with light from a light source and projects light from the image display element through two polarization split surfaces, when the angles of first and second light rays, of light rays incident on the polarization split surface, with respect to the optical axis correspond to 55% of the maximum angle of the incident light rays with respect to the optical axis, where light rays of which incident angle with respect to said image display element is larger is set as first light ray and light rays of which incident angle with respect to said image display element is smaller is set as second light ray, and a light shielding characteristic value L on the two polarization split surfaces is represented by L&equals;&lsqb;(M )a&middot;(M )b&plus;(M )a&middot;(M )b&rsqb;/2 where (M )a is the amount of leakage light of the first light ray on the polarization split on the reflection image display element side, (M )a is the amount of leakage light of the second light ray, (M )b is the amount of leakage light of the first light ray on the polarization split on the projection optical system side, and (M )b is the amount of leakage light of the second light ray.

Projection image display apparatus

An image display apparatus includes a light source for supplying illumination light, a reflection type display element for modulating the illumination light into image light by reflecting the light, an illumination optical system for guiding the illumination light to the reflection type display element, and a projection optical system for guiding the image light to an observer. The image light is incident on the projection optical system via at least a portion of the illumination optical system. The illumination optical system has a part, in an area where both the illumination light and the image light pass, which changes an optical action depending on a state of incident light. The part acts to deflect the illumination light to decrease an incident angle with respect to the reflection type display element as compared with a case where the part does not exist.

Image display apparatus and optical system

A focus state detection apparatus for detecting focus state on the basis of signals outputted from a pair of area sensors each of which is configured in two dimension in accordance with an image of an object passing through an optical system and formed on the pair of area sensors. Each of the pair of area sensors is divided into a plurality of areas each of which can be controlled independently, and charging pixels of the area sensors is controlled by each pair of corresponding divided areas of the area sensors.

Focus state detection apparatus with image sensing device controls

An anti-fog article is obtained by coating a substrate with an anti-fog coating material to form thereon an anti-fog coating film that is hydrophillic, moisture-absorptive, insoluble and excellent in surface hardness. The anti-fog coating material contains a polyacrylic acid compound, polyvinyl alcohol and acetylacetone, and optionally sodium silicate.

Anti-fog coating material and method of preparing an anti-fog article

A camera, or an underwater camera in particular, includes a photo-taking optical unit for photo-taking an object, and a viewfinder optical unit for observing the object, wherein an antifogging film is applied to an inner side of an optical member which is disposed in an optical path of at least one of the photo-taking optical unit and the viewfinder optical unit and which comes into contact with an external medium relative to the camera.

Camera having antifogging film

Disclosed herein is an anti-fogging coating material comprising at least one selected from the group consisting of an inorganic alkoxide, a hydrolysate of the inorganic alkoxide and a polycondensate of the hydrolysate of the inorganic alkoxide, a polyacrylic, and polyvinyl alcohol.

Anti-fogging coating material, anti-fogging coating film and anti-fogging article

A focus detecting device of the kind using an area sensor which has a plurality of focus detecting areas necessitates setting a correction value for every one of the focus detecting areas and storing all the correction values thus obtained, whereas, according to the invention, the correction value for each of the focus detecting areas of the area sensor is obtained by an arithmetic operation using, as variables, two parameters indicative of the position of the area, so that a focus detecting device can be arranged to obviate the necessity of storing all the correction values for the respective focus detecting areas.

Focus detecting device

An observation optical system whose eye relief is below 25 mm includes an eyepiece lens having a water absorptive antifogging coating applied on one surface thereof, and a member holding the eyepiece lens. Further, an eyeball-characteristic detecting system includes a light source for illuminating the eyeball of an observer, a light receiving element arranged on detection of the reflected light from the eyeball through the eyepiece to produce a signal, an optical member positioned in the path of the light from the light source to the light receiving element and having an antifogging coating on one surface thereof, and a circuit receptive of the signal for detecting the characteristic of the eyeball.

Observation optical system and optical apparatus having the same

A camera comprising: finder means for inspecting an object, illumination means for illuminating an operator's eye by which the operator looks in at the finder means, a condensing optical system for condensing a reflected light from the operator's eye, photoelectric converter means for receiving the condensed reflected light, calculation means for calculating a direction of a visual axis of the operator's eye on the basis of an output of the photoelectric converter means, and condition setting means operable in response to the result of the calculation of the calculation means, for setting taking conditions of the camera.

Camera with visual axis detecting device

A semiconductor optical device is provided with a photo-electric conversion unit having plural photo-electric conversion elements and is entirely sealed by a sealing member. The photo-electric conversion elements are connected to external leads with electrical connectors. The distance D between a planar outer surface and a photoelectric conversion area satisfies the equation, D.gtoreq./2.multidot.l/tan .theta., where .theta. is a critical angle of total reflection of the sealing member with respect to air and l is the maximum length of said photoelectric conversion area.

Growing community of inventors

Yokohama, Japan

Keiji Ohtaka