Abstract: A compiler, which makes a computer carry out a process for generating a program used for a remote access to a virtual database comprising a first computer 11 including an application program and a second computer 12 being connected to the first computer 11 by way of a network and including one or more databases, replaces (1c) a description part relating to a DML execution process for the virtual database from a source code 7 of the application program with a description relating to an RPC process and generates a program for executing the DML execution process for the native databases based on the RPC process. The use of the program enables a high performance remote database access while applying a virtual database function aiming at facilitating a business logic buildup.

Abstract: A wide-angle optical system comprises, in order from its object side, a stop, a first lens (L1) having positive refracting power, a second lens (L2) having negative refracting power and a third lens (L3) that is an aspheric lens. The third lens is configured such that as viewed in a lens section including an optical axis, a portion thereof near the optical axis is in a meniscus shape convex on an object side thereof, and an object side surface and an image side surface thereof at a peripheral site are in a meniscus shape convex on an image side thereof. The optical system satisfies the following conditions (1-1) and (1-2). ?0.40<f/f3<0.15??(1-1) 0.30<hc7/hp7<2.0??(1-2) where f is the focal length of the whole wide-angle optical system, and f3 is the focal length of the third lens.

Abstract: The invention provides a viewing optical system positioned between a viewing plane as a virtual plane and an eye point. The viewing optical system comprises, in order from the viewing plane side, a cemented lens and a positive lens component, and satisfies the following condition (1). 0.2<Dm/L<0.8??(1) where Dm is the widest of lens-to-lens spaces in the viewing optical system, and L is a distance of said viewing plane to a lens surface positioned in the viewing optical system and nearest to the eye point side.

Abstract: The invention provides a viewing optical system positioned between a viewing plane as a virtual plane and an eye point. The viewing optical system comprises, in order from the viewing plane side, a cemented lens in which at least one negative lens and at least one positive lens are cemented together and one positive lens, and satisfies the following condition (1). ?8<r3/f<?0.2??(1) Here r3 is the radius of curvature of the lens surface positioned in the cemented lens and nearest to the viewing plane side, and f is the focal length of the whole viewing optical system.

Abstract: The invention provides a viewing optical system positioned between a viewing plane as a virtual plane and an eye point. The viewing optical system comprises, in order from the viewing plane side, a first lens group including a positive lens or a negative lens, a second lens group including a cemented lens in which at least one negative lens and at least one positive lens are cemented together, and a third lens group including a positive lens. Of lenses forming the first, second, and third lens groups, at least one lens surface is an aspheric surface.

Abstract: The present invention provides a viewfinder, characterized by comprising a reflection type display device on which an object image is displayed, an eyepiece optical system having a front group and a rear group, an illumination optical system for illuminating the reflection type display device and an optical device for putting an optical path taken by the illumination optical system over an optical path from said reflection type display device to the eyepiece optical system at a position of the widest of lens-to-lens spaces in the eyepiece optical system. The eyepiece optical system is located between the reflection type display device and an eye point, and satisfies the following condition (1): 0.1<Y/Dm<1??(1) where Dm is the widest lens-to-lens space, and Y is the length of the reflection type display device from the center to one side thereof.

Abstract: The invention provides a viewing optical system positioned between a viewing plane as a virtual plane and an eye point. The viewing optical system comprises, in order from the viewing plane side, a first lens and a filter.

Abstract: An optical system is presented that enables images of a wide range of natural subjects to be well reproduced with their colors, and provides an image pickup system including, at least, an image pickup optical system, an electronic image pickup device having three or more different spectral characteristics to obtain a color image, and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in determining the focal length in the image pickup system includes an optical element making use of a refraction phenomenon alone.

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: The present invention concerns an imaging apparatus which works for size reductions, power savings, the efficient attainment of the quantity of light sensed, and prevention of contrast decreases due to a diffraction phenomenon, is well fit for the taking and appreciation of common still pictures, and comprises a taking lens and electronic imaging device combination that takes full advantage of the characteristics of an imaging device. The imaging apparatus comprises a taking optical system, and an electronic imaging device which is located on an image side of said taking optical system, includes an imaging plane I with a plurality of two-dimensionally arranged light sensors, and is adapted to convert an image formed through said imaging optical system into electrical signals.

Abstract: An optical system is presented that enables images of a wide range of natural subjects to be well reproduced with their colors, and provides an image pickup system including, at least, an image pickup optical system, an electronic image pickup device having three or more different spectral characteristics to obtain a color image, and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in determining the focal length in the image pickup system includes an optical element making use of a refraction phenomenon alone.

Abstract: An image pickup apparatus that comprises: an optical path splitting element; an optical system including a variable-optical-power element which is substantially immobile in an optical axis direction and a reflective surface; and an image pickup surface, the variable-optical-power element, the optical system, and the image pickup surface being arranged so that a ray from an object side is divided into two rays by the optical path splitting element, at least one of the rays enters the optical system, and is reflected by the reflective surface to return to the optical path splitting element, and the ray strikes on the image pickup surface via the optical path splitting element.

Abstract: An optical system enables images to be well reproduced with their colors, and provides an image pickup system including an image pickup optical system, an electronic image pickup device to obtain a color image and a controller for implementing signal processing or image processing on the basis of an output from the electronic image pickup device. The optical element that takes part in the determination of a focal length includes an optical element making use of a refraction phenomenon alone. The 400-nm wavelength input/output ratio is 10% or less with respect to an input-output ratio for a 400-nm to 800-nm wavelength at which an output signal strength ratio with respect to an input quantity of light is highest when the input quantity of light is defined by the quantity of a light beam emanating from the same object point and entering the image pickup optical system and the output signal strength is defined by the strength of a signal produced from the controller in response to the light beam.

Abstract: A wide-angle optical system comprises, in order from its object side, a stop, a first lens (L1) having positive refracting power, a second lens (L2) having negative refracting power and a third lens (L3) that is an aspheric lens. The third lens is configured such that as viewed in a lens section including an optical axis, a portion thereof near the optical axis is in a meniscus shape convex on an object side thereof, and an object side surface and an image side surface thereof at a peripheral site are in a meniscus shape convex on an image side thereof. The optical system satisfies the following conditions (1-1) and (1-2). ?0.40<f/f3<0.15 ??(1-1) 0.30<hc7/hp7<2.0 ??(1-2) where f is the focal length of the whole wide-angle optical system, and f3 is the focal length of the third lens.

Abstract: A reflection type projecting screen includes a diffuse plate having a diffuse transmission surface for converting at least transmission light into diffused light and a corner cube array for reflecting the light passing through the diffuse plate to a position which is approximately similar to a passing position of the diffuse transmission surface. The diffuse plate and the corner cube array are positioned in an order of the diffuse plate and the corner cube array. The reflection screen is capable of improving utilization efficiency of light and simplifying the structure while reducing the effect of outside light. Furthermore, there are provided a front projector system and a multi-vision projector system each of which has a projector for projecting the projection light and a reflection screen for reflecting the projection light as diffused light having directivity in at least one predetermined direction, in accordance with the incident direction of the projection light.

Abstract: In a camera of the invention, during focus detection, luminous flux from an object is transmitted by a main mirror via an imaging lens, and then, is reflected by a reflection face of a sub-mirror. The reflected luminous flux is reflected by the main mirror, passes through a field stop, and is reflected by a guide mirror. The luminous flux reflected by this guide mirror is incident on a photoelectric converter element through a diaphragm and a refocusing lens. The luminous flux reflected by the main mirror reaches an eyepiece lens through a focusing glass and a pentaprism. During imaging, the main mirror and the sub-mirror are retracted from the imaging optical path. The luminous flux having passed through the imaging lens is guided to an image pickup device via an infrared filter and a low-pass filter.

Abstract: A compound lens on which a plastic lens is formed on a glass lens, having: an annular step part which is formed on the end part of the optical functional surface, on which the plastic lens is formed, on the outer circumference side on the outside of the outermost diameter of the optical functional surface and which is formed for directly mounting on a resin-made lens tube frame; and a caulk-fix part, being formed, in a form of a chamfer, in the outer form part of the glass lens on the optical functional surface on the opposite side of the optical functional surface on which the plastic lens is formed, wherein an influence of a heat on the plastic lens is eliminated when fixing the glass lens onto the resin-made lens tube frame by means of thermal caulking.

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: In a finder optical system, a primary image is formed by an objective lens on a primary image formation face and is passed via a relay optical system to form a secondary image on a secondary image formation face. This secondary image is observed via an ocular lens system. A diffuser is arranged at the position of the secondary image formation face.

Abstract: A zoom optical system includes, in order from the object side, a first lens unit with positive refracting power, a second lens unit with negative refracting power, a third lens unit with positive refracting power, and a fourth lens unit with positive refracting power. An aperture stop is interposed between the second lens unit and the fourth lens unit. Upon zooming, at least, the first lens unit, the second lens unit, and the third lens unit are moved so that spacings between these lens units are varied. The first lens unit is constructed with at most two lens elements. The second lens unit includes, in order from the object side, a first negative lens in which the image-side surface is greater in curvature than the object-side surface, an air spacing, a second negative lens in which the image-side surface is greater in curvature than the object-side surface, an air spacing, and a positive lens in which the object-side surface is greater in curvature than the image-side surface.