Abstract: An electronic pen indicates a position to a position detection module by transmitting and receiving signals with the position detection module. A cylindrical casing, a core member, a writing-pressure detector, and a writing-pressure transmission member are accommodated in a interior portion of a cylindrical casing. A pressing member applies, based on a user operation, a displacement force to the core member from a first end, which is opposite to a second end serving a pen tip, to the second end serving as the pen tip. The writing-pressure transmission member includes a protrusion which, in operation, transmits a writing pressure, which has been exerted on the core member fitted in a fit-in portion included in the writing-pressure transmission member, to the writing-pressure detector. The pressing member is configured to apply a displacement force to the core member via the writing-pressure transmission member without applying an axial force to the writing-pressure detector.

Abstract: A position indicator includes a first electrode receiving an alternating current (AC) signal from a position detecting sensor and a second electrode transmitting an AC signal to the position detecting sensor. The position indicator includes: a tubular pen-shaped chassis; a central electrode provided such that one end protrudes outside of the chassis from an opening of the chassis, and formed of an electrically-conductive member forming a first one of the first and second electrodes; a peripheral electrode surrounding the central electrode and formed of an electrically-conductive member forming a second one of the first and second electrodes; and a shield member having a hollow part housing at least a part of the central electrode surrounded by the peripheral electrode. The shield member includes a tubular part electrically connected to ground and an insulating layer formed on an inner wall surface and an outer wall surface of the tubular part.

Abstract: An electronic pen indicates a position to a position detection module by transmitting and receiving signals with the position detection module. A cylindrical casing, a core member, a writing-pressure detector, and a writing-pressure transmission member are accommodated in a hollow section of a cylindrical casing. Provided is a pressing member that applies, based on an operation by a user, a displacement force to the core member from a first end, which is opposite to a second end serving a pen tip, to the second end serving as the pen tip. The writing-pressure transmission member includes a protrusion which, in operation, transmits a writing pressure, which has been exerted on the core member fitted in a fit-in portion included in the writing-pressure transmission member, to the writing-pressure detector. The pressing member is configured to apply a displacement force to the core member via the writing-pressure transmission member without applying an axial force to the writing-pressure detector.

Abstract: A position indicator includes a first electrode receiving an alternating current (AC) signal from a position detecting sensor and a second electrode transmitting an AC signal to the position detecting sensor. The position indicator includes: a tubular pen-shaped chassis; a central electrode provided such that one end protrudes outside of the chassis from an opening of the chassis, and formed of an electrically-conductive member forming a first one of the first and second electrodes; a peripheral electrode surrounding the central electrode and formed of an electrically-conductive member forming a second one of the first and second electrodes; and a shield member having a hollow part housing at least a part of the central electrode surrounded by the peripheral electrode. The shield member includes a tubular part electrically connected to ground and an insulating layer formed on an inner wall surface and an outer wall surface of the tubular part.

Abstract: A position indicator includes a first electrode receiving an alternating current (AC) signal from a position detecting sensor and a second electrode transmitting an AC signal to the position detecting sensor. The position indicator includes: a tubular pen-shaped chassis; a central electrode provided such that one end protrudes outside of the chassis from an opening of the chassis, and formed of an electrically-conductive member forming a first one of the first and second electrodes; a peripheral electrode surrounding the central electrode and formed of an electrically-conductive member forming a second one of the first and second electrodes; and a shield member having a hollow part housing at least a part of the central electrode surrounded by the peripheral electrode. The shield member includes a tubular part electrically connected to ground and an insulating layer formed on an inner wall surface and an outer wall surface of the tubular part.

Abstract: A position indicator includes a first electrode receiving an alternating current (AC) signal from a position detecting sensor and a second electrode transmitting an AC signal to the position detecting sensor. The position indicator includes: a tubular pen-shaped chassis; a central electrode provided such that one end protrudes outside of the chassis from an opening of the chassis, and formed of an electrically-conductive member forming a first one of the first and second electrodes; a peripheral electrode surrounding the central electrode and formed of an electrically-conductive member forming a second one of the first and second electrodes; and a shield member having a hollow part housing at least a part of the central electrode surrounded by the peripheral electrode. The shield member includes a tubular part electrically connected to ground and an insulating layer formed on an inner wall surface and an outer wall surface of the tubular part.

Abstract: A projection optical system includes first and second optical systems. The first optical system includes a transmissive-refractive element and the second optical system includes a reflective-refractive element. An image formed by a spatial light modulator is projected by the projection optical system on a projection surface. A light beam that travels along an optical path that leads from the second optical system to the projection surface in an optical path between a center of the image formed by the spatial light modulator and the projection surface is projected at an angle with respect to a normal to the projection surface. An optical axis of the first optical system is folded to a folded position by an optical path deflecting unit in an area of the first optical system where the light beam entering the optical path deflecting unit is a converging light beam or a substantially parallel light beam.

Abstract: Disclosed are a projection display apparatus and a projection optics provided in the projection display apparatus. The projection optics has a refractive optics and a reflective optics. In the refractive optics, a lens (non-circular lens) provided on a reflective optics side has a non-circular shape forming part of an imaginary circular region whose center is an optical axis center of the refractive optics. In other words, the non-circular lens has a shape of a cut-out portion of an imaginary circular lens having an optical axis center coinciding with the optical axis center of the refractive optics.

Abstract: A projection optical system includes first and second optical systems. The first optical system includes a transmissive-refractive element and the second optical system includes a reflective-refractive element. An image formed by a spatial light modulator is projected by the projection optical system on a projection surface. A light beam that travels along an optical path that leads from the second optical system to the projection surface in an optical path between a center of the image formed by the spatial light modulator and the projection surface is projected at an angle with respect to a normal to the projection surface. An optical axis of the first optical system is folded to a folded position by an optical path deflecting unit in an area of the first optical system where the light beam entering the optical path deflecting unit is a converging light beam or a substantially parallel light beam.

Abstract: A projection optical apparatus capable of providing high image quality and having a reduced size is disclosed. The projection optical apparatus includes a light valve and a projection optical system including a first optical system having a transmissive-refractive element and a second optical system having a reflective-refractive element. An image formed on the light valve is projected by the projection optical system on a projection surface. The optical axis in the first optical system is folded both vertically and horizontally. The first group of the first optical system is contained in a space (dead space) whose lower limit is defined by a lower edge of the second optical system, thereby reducing the depth of the apparatus.

Abstract: An optical system with short total length to project a high quality large image. The system projects an image onto a projection surface, and includes a lens system having a plurality of lenses, and one or more curved mirrors. Light flux of an enlarged image shooting out from the lens system to the projection surface is incident onto a mirror surface of the one of the curved mirrors first of all. Distances OAL and Y satisfy a requirement 20 <OAL/Y <30. OAL is between the image surface and the surface of the curved mirror nearest the projection surface and along an optical path shared by the most lenses of the lens system, and on the image surface. Y is between the optical axis shared by the most lenses and an edge of the image surface which is farthest from the optical axis shared by the most lenses.

Abstract: A projection optical system includes a first refracting optical system having a plurality of lenses, a first reflecting optical system, and a second reflecting optical system. The first reflecting optical system is disposed on a side of a projection port with respect to an optical axis of the first refracting optical system, and has a positive optical power to reflect light incident through the first refracting optical system in a direction opposite to the side of the projection port. The second reflecting optical system is operable to reflect the light reflected on the first reflecting optical system toward the projection port.

Abstract: Disclosed are a projection display apparatus and a projection optics provided in the projection display apparatus. The projection optics has a refractive optics and a reflective optics. In the refractive optics, a lens (non-circular lens) provided on a reflective optics side has a non-circular shape forming part of an imaginary circular region whose center is an optical axis center of the refractive optics. In other words, the non-circular lens has a shape of a cut-out portion of an imaginary circular lens having an optical axis center coinciding with the optical axis center of the refractive optics.

Abstract: A projection optical apparatus capable of providing high image quality and having a reduced size. The projection optical apparatus comprises a light valve and a projection optical system including a first optical system (5) having a transmissive-refractive element and a second optical system (3?) having a reflective-refractive element. An image formed on the light valve is projected by the projection optical system on a projection surface (4). The optical axis in the first optical system (5) is folded both vertically and horizontally. The first group (5A) of the first optical system is contained in a space (dead space) whose lower limit is defined by a lower edge of the second optical system (3?)/thereby reducing the depth of the apparatus.

Abstract: A projection optical system which has a short total length but can project a high quality and large image. The projection optical system projects the displayed image on an image displaying surface onto a projection surface, and includes a lens system having a plurality of lenses, and one or more curved mirrors. Light flux of an enlarged image shooting out from the lens system to the projection surface is incident onto a mirror surface of the one of the curved mirrors first of all. A distance OAL and a distance Y satisfy a requirement (1) 20<OAL/Y<30, OAL being the distance between the image surface and the surface of the curved mirror nearest the projection surface and along an optical path shared by the most lenses of the lens system, and on the image surface, and the distance Y being the distance between the optical axis shared by the most lenses and an edge of the image surface which is farthest from the optical axis shared by the most lenses.

Abstract: A projection optical system includes a first refracting optical system having a plurality of lenses, a first reflecting optical system, and a second reflecting optical system. The first reflecting optical system is disposed on a side of a projection port with respect to an optical axis of the first refracting optical system, and has a positive optical power to reflect light incident through the first refracting optical system in a direction opposite to the side of the projection port. The second reflecting optical system is operable to reflect the light reflected on the first reflecting optical system toward the projection port.

Abstract: An illumination apparatus includes a reflector including a parabolic or ellipsoidal mirror, a light source arranged near a (first) focal point of the reflector, and a front mirror having a transparent window and a mirror surface symmetrical about the light axis. Luminous flux emitted from the light source is reflected from the reflector. In the case of the parabolic mirror, the front mirror has the same size as an entrance of an output light utilizing optical system, and the luminous flux exits toward the optical system as collimated light. In the case of the ellipsoidal mirror, the front mirror is arranged between two focal points of the ellipsoidal mirror, and the luminous flux is directed toward the second focal point. However, at least one part of the luminous flux is reflected from the front mirror and returned toward the first focal point.

Abstract: An illumination apparatus includes a reflector including a parabolic or ellipsoidal mirror, a light source arranged near a (first) focal point of the reflector, and a front mirror having a transparent window and a mirror surface symmetrical about the light axis. Luminous flux emitted from the light source is reflected from the reflector. In the case of the parabolic mirror, the front mirror has the same size as an entrance of an output light utilizing optical system, and the luminous flux exits toward the optical system as collimated light. In the case of the ellipsoidal mirror, the front mirror is arranged between two focal points of the ellipsoidal mirror, and the luminous flux is directed toward the second focal point. However, at least one part of the luminous flux is reflected from the front mirror and returned toward the first focal point.

Abstract: An illumination apparatus includes a reflector including a parabolic or ellipsoidal mirror, a light source arranged near a (first) focal point of the reflector, and a front mirror having a transparent window and a mirror surface symmetrical about the light axis. Luminous flux emitted from the light source is reflected from the reflector. In the case of the parabolic mirror, the front mirror has the same size as an entrance of an output light utilizing optical system, and the luminous flux exits toward the optical system as collimated light. In the case of the ellipsoidal mirror, the front mirror is arranged between two focal points of the ellipsoidal mirror, and the luminous flux is directed toward the second focal point. However, at least one part of the luminous flux is reflected from the front mirror and returned toward the first focal point.

Abstract: An illumination apparatus includes a reflector including a parabolic or ellipsoidal mirror, a light source arranged near a (first) focal point of the reflector, and a front mirror having a transparent window and a mirror surface symmetrical about the light axis. Luminous flux emitted from the light source is reflected from the reflector. In the case of the parabolic mirror, the front mirror has the same size as an entrance of an output light utilizing optical system, and the luminous flux exits toward the optical system as collimated light. In the case of the ellipsoidal mirror, the front mirror is arranged between two focal points of the ellipsoidal mirror, and the luminous flux is directed toward the second focal point. However, at least one part of the luminous flux is reflected from the front mirror and returned toward the first focal point.