Canon Kabushiki Kaisha

Other

Takashi Sudo

Atsushi Okuyama

Hiroyuki Kodama

Yuuki Maeda

Yu Yamauchi

Junko Kuramochi

Makoto Takahashi

Keiji Ohtaka

Kazuhiro Inoko

Toshio Inbe

Tatsuo Chigira

Shinji Yamasaki

Masahiko Matsukawa

Toshiki Ishino

Tatsuo Yoshida

Shintaro Nakagawa

Masahiro Kojima

Ryota Kadowaki

An illumination optical system illuminates an image display element and includes a first lens array configured to divide light emitted from a light source, a second lens array configured to receive light from the first lens array, and a condenser optical system configured to guide light from the second lens array to the image display element, and a conjugate point of the image display element is located between an incident surface of the first lens array and an incident surface of the second lens array.

Illumination optical system and image projection apparatus with the same

A fundus imaging apparatus according to embodiments of the present invention includes an optical unit configured to guide light from a fiber light source to a fundus of a subject eye, a wavefront sensor capable of measuring the wavefront of reflected light guided via the optical unit after the light from the fiber light source is reflected on the fundus, a wavefront correction device provided on an optical path extending between the fiber light source and the subject eye to correct the wavefront of the reflected light, an APD that can receive the reflected light and capture an image of the fundus, and a processing and control unit configured to acquire thickness information about an optical diffusive layer of the fundus and determine a correction value to be used when the wavefront correction device corrects the wavefront of the reflected light based on the acquired thickness information.

Fundus imaging apparatus and method for controlling the same, and storage medium

An ophthalmic apparatus capable of suppressing ghost, and securing a necessary amount of working distance even when an eye to be inspected has a diopter on a myopia side, includes: a large area image acquisition unit acquiring a large area image of a fundus of the eye to be inspected at a low resolution based on return light of first measuring light from the fundus; a small area image acquisition unit acquiring a small area image of the fundus at a high resolution based on return light of second measuring light from the fundus; and a dichroic prism combining the first measuring light and the second measuring light, and dividing the return light, in which the large area image acquisition unit includes an optical member having a positive optical power, which is arranged at a position opposite to the eye to be inspected with respect to the dichroic prism.

Ophthalmic apparatus

An optical unit includes a plurality of paraboloid mirrors configured to reflect light fluxes from a plurality of LDs and to guide them to a concave lens. The light fluxes from the paraboloid mirrors are a plurality of convergent light fluxes, and the paraboloid mirrors reflect the light fluxes from the LDs such that as the convergent light fluxes travel farther away from the paraboloid mirrors, distances therebetween become shorter.

Optical unit, optical apparatus using the same, light source apparatus, and projection display apparatus

An illumination optical system includes a first compression system configured to compress a light flux on each of first and second sections, a second compression system configured to compress the light flux on the first section, a polarization converter arranged so that a section that contains a normal of the second polarization splitting surface and the optical axis becomes the second section, and configured to convert non-polarized light into linearly polarized light, a first lens array arranged in front of the polarization converter along an optical path, and a second lens array arranged between the first lens array and the polarization converter along the optical path. Both of the first lens array and the second lens array have no optical power on the second section.

Illumination optical system with light-compressing lens arrays having no optical power on one section and image projection apparatus having the same

An illumination optical system includes first and second lamp units, a light combining portion that combines a light beam from the first lamp unit and a light beam from the second lamp unit, at least one light returning portion disposed between the first lamp unit and the light combining portion, or between the second lamp unit and the light combining portion, or both, the or each of the at least one light returning portion dividing a part of light emitted from the corresponding lamp unit into a light beam to be returned to the lamp and a light beam to be led to the light combining portion, and a condenser lens that condenses light from the light combining portion.

Illumination optical system having a light combining portion that combines light beams from a plurality of lamp units and projection display apparatus

An illumination optical system and a projection display apparatus include a beam combining portion and a condensing lens condensing a beam from the beam combining portion. The beam combining portion combines beams from first and second lamp units each including a lamp and a concave mirror, the lamp having a cathode and an anode arranged along an optical axis of the concave mirror. The beam combining portion includes a first reflective section disposed on an optical axis of the first lamp unit and off the optical axis of the second lamp unit and a second reflective section disposed off the optical axis of the first lamp unit. The first and second reflective sections reflect a beam that is emitted from the second lamp unit and that is off an optical axis thereof to combine the beams from the first and second lamp units.

Illumination optical system and projection display apparatus

A color separation optical system is disclosed which is effective in improving black color and black unevenness. Linearly polarized light impinging on a dichroic surface at an incident angle smaller than 45 degrees and then impinging on a polarization beam splitting surface at an incident angle larger than 45 degrees is referred to as first incident-angle light. A wavelength which is longer than a wavelength at the maximum transmittance of the dichroic surface for the first incident-angle light and at which the transmittance of the dichroic surface for the first incident-angle light is 10% is referred to as Wa, and a wavelength range shorter than Wa is referred to as W. The polarization beam splitting surface has a characteristic in which its transmittance for the first incident-angle light in the wavelength range W is 5% or lower.

Color separation optical system and image projection apparatus

An illumination optical system has a condenser, a first lens array, a second lens array, and a polarized beam splitting surface. The condenser and the first and second lens arrays compress light incident on the condenser. The distance between a lens cell in the first lens array and a lens cell in the second lens array is appropriately set, whereby an illuminated surface is illuminated brightly and efficiently without significant loss of light amount.

Illumination optical system and image projector using same

An optical system for image projection is disclosed which is capable of improving contrast while suppressing reduction of light amount. The optical system includes a converging optical system, and a polarization beam splitting surface transmitting an incoming light flux having a first polarization direction from the converging optical system, to introduce it to the image-forming element and causing light having a second polarization direction, of an outgoing light flux from the image-forming element, to proceed to a projection optical system. In a first cross-section parallel to a normal to the polarization beam splitting surface, the converging optical system has a configuration causing an incident angle on the splitting surface of a light ray passing through a barycenter of intensity distribution of the outgoing light flux to be larger than an incident angle thereon of a light ray passing through a barycenter of intensity distribution of the incoming light flux.

Optical system for image projection and image projection apparatus including a polarization beam splitting surface

An optical system for image projection is disclosed which is easy to be manufactured and designed and capable of projecting a bright image with high contrast. The optical system includes an illumination optical system introducing a luminous flux emitted from a light source to an image-forming element through an optical surface having a light-splitting function, and a projection optical system projecting the luminous flux from the image-forming element through the optical surface onto a projection surface. The illumination optical system includes a conversion system which respectively converts the widths of the luminous flux in first and second cross-sections into widths different from those before entering thereinto. Conversion rates in the first and second cross-sections are different from each other.

Illumination optical system including luminous flux conversion system

An illumination optical system is disclosed which capable of uniformly illuminating a surface to be illuminated. The illumination optical system comprises a polarization conversion element which converts a luminous flux from a light source into a luminous flux having a certain polarization direction, a polarization beam splitter which splits the luminous flux from the polarization conversion element, and a phase plate which gives a phase difference to the luminous flux from the polarization beam splitter. The system illuminates the surface with the luminous flux from the phase plate and satisfies the conditions &#x3b8;x&#x3c;&#x3b8;y and 0&#xb0;&#x3c;&#x3c6;y&#x3c;&#x3b8;y. &#x3b8;x and &#x3b8;y represent the maximum incident angles onto the surface in the x and y directions, and &#x3c6;y represents an incident angle onto the phase plate at which the phase difference at a principal wavelength of the luminous flux that passes through the phase plate is 90 degrees.

Illumination optical system and image projection apparatus

Provided is a projection lens, including: a plurality of moving lens units that move on an optical axis for zooming; and a plurality of plastic lenses containing plastic, in which when a focal distance of an i-th positive lens from a predetermined plane side of N positive lenses of the plurality of plastic lenses is given by fpi, a focal distance of a j-th negative lens from the predetermined plane side of M negative lenses of the plurality of plastic lenses is given by fnj, and fp and fn are defined by (N and M each are a natural number, that is, an integer equal to or larger than 1), &#x2212;0.56&#x3c;fn/fp&#x3c;&#x2212;0.05 is satisfied.

Zoom lens and image display apparatus including the zoom lens

An image display apparatus includes a light source for supplying illumination light, a reflection type display device which reflects the illumination light and modulates the illumination light into image light, and an illumination optical system for guiding the illumination light to the reflection type display device. The illumination optical system includes a first optical member for directing the illumination light toward the reflection type display device, and a second optical member. The second optical member includes a part generating a secondary light source with the illumination light emitted from the light source, in which the light from the part emerges toward the first optical member, and a reflecting surface which guides illumination light which is not incident directly on the part to the part. In addition, a projection optical system guides the image light to an observer.

Growing community of inventors

Utsunomiya, Japan

Takashi Sudo