Abstract: An imaging lens is provided and includes: a stop; and a lens group disposed between the stop and an imaging plane of the imaging lens and having a positive power as a whole. The lens group has an air lens formed by an air gap between lenses adjacent to each other, and the imaging lens satisfies conditional expression (1): ?8<L×(1/Ra2?1/Ra1)<?3 ??(1) Ra1 represents a radius of curvature of an object-side surface of the air lens which has a convex shape and is closest to an image side of the imaging lens in the lens group, Ra2 represents a radius of curvature of an image-side surface of the air lens, and L represents a distance on an optical axis of the imaging tens from an object-side surface of a lens closest to an object side in the imaging lens to an imaging plane.

Abstract: A zoom lens includes, in order from a magnification side, a negative first lens group for focus adjustment adapted to be fixed during power-varying, a positive second lens group adapted to move during power-varying, a negative third lens group, a positive fourth lens group, and a positive fifth lens group, and a positive sixth lens group adapted to be fixed during power-varying, the sixth lens group having a stop arranged nearest to the magnification side. Each lens is a single lens. A ratio of a back focal length of the entire system to a focal length at a wide-angle end of the entire system is larger than 2.5, and Fno. is set constant over the whole region of power-varying.

Abstract: A balloon control apparatus includes a balloon, a flow rate adjustment section, a setting section and a control section. The balloon is attached to an insertion section of an endoscope and/or an insertion aid instrument for guiding insertion of the insertion section of the endoscope. The flow rate adjustment section adjusts an air supply flow rate to the balloon and/or an exhaust flow rate from the balloon. The setting section sets the air supply flow rate and/or the exhaust flow rate. The control section controls the flow rate adjustment section so that the air supply flow rate to the balloon and/or the exhaust flow rate from the balloon become the air supply flow rate and/or the exhaust flow rate set by the setting section.

Abstract: A reflecting mirror with a reflective multi-layer coating capable reflecting light beams of discrete wavelengths, e.g., laser beams in the wave ranges of CD, DVD and mass storage optical discs, free of the problem of light absorption.

Abstract: A small projection lens includes a first lens, which is a biconvex lens, an aperture, an aperture diaphragm (or an aperture), a second lens, which is a negative meniscus lens having a concave surface facing a magnification side, a third lens, which is a positive meniscus lens having a convex surface facing a reduction side, and a fourth lens, which is a biconvex lens having aspheric surfaces at both sides on an optical axis, arranged in this order from the magnification side. A minimum portion of the length of all lens elements of the small projection lens in a diametric direction vertical to the optical axis is equal to or less than 15 mm, and the small projection lens satisfies the following conditional expression: 2.5<?/S<10.0 (where S indicates the maximum length of a magnification-side image (inch) and ? indicates a magnifying power).

Abstract: The light wave interferometer apparatus is provided and includes: a luminous flux, which is sent from the light source and divided into two portions by the luminous flux separation and composition unit, are combined with each other again under the condition that the divided luminous fluxes hold wavefront information corresponding to the surface shapes of the aspherical lens to be inspected and the reference aspherical lens by the respectively corresponding basis spherical lenses. Therefore, a wavefront difference of the aspherical lens to be inspected with respect to the reference aspherical lens is made to be interference fringe information and formed on an image pickup plane of the interferometer CCD camera. The basis spherical lenses have the basis spherical surfaces, the curvatures of which are equal to each other.

Abstract: Disclosed are a projection lens that is faster than F1.95 and has a simple inner focus structure, a high optical performance, and a small size, and a projection display device. A projection lens includes a first lens group having a negative refractive power, a second lens group having a positive refractive power, and a third lens group having a positive refractive power arranged in this order from a magnification side. A fifth lens arranged closest to a reduction side in the first lens group is moved along an optical axis to adjust focus. The projection lens satisfies the following conditional expression: 0.2<DG12/f<0.8 where DG12 indicates a distance between the first lens group and the second lens group and f indicates the focal length of the entire lens system.

Abstract: An electronic endoscope apparatus includes an imaging element and a signal processing unit. The imaging element obtains an image of an observation object, and outputs an image signal of the observation object. The signal processing unit alternately repeats obtainment of a partial image signal using a part of a light receiving area of the imaging element and obtainment of a partial image signal using the remaining part of the light receiving area. The signal processing unit also obtains a whole image signal corresponding to an image of the observation object using a partial image signal obtained in the n-th (n is a natural number) obtainment and a partial image signal obtained in the (n+1)th obtainment. Further, a partial component of the n-th partial image signal is extracted by an extraction unit, and the extracted partial component is added to the (n+1)th partial image signal.

Abstract: A focus information display system is provided in which focus state detection that is performed during automatic focusing (AF) and the like is also performed during manual focusing (MF) and the like to display focus information indicating a focus state. By arranging a focus position range at which a correct focus state is determined when a correct focus display is being performed to be wider than a focus position range at which a correct focus state is determined when an out-of-focus display is being performed, stabilization of a state of correct focus display is achieved without jeopardizing correct focusing accuracy when performing focusing according to a focus information display.

Abstract: The evaluating apparatus evaluates a restoration-premised lens which is employed in an image forming system that converts an optical image into an electronic image and then enforces a restoration processing on the electronic image in order to obtain a sharp image, is actually manufactured based on such design as premised on the restoration processing. The evaluating apparatus includes an evaluating corrective optical system, measuring section and evaluating section. The evaluating corrective optical system, when it is combined with a lens manufactured just as designed, forms a sharp optical image. The measuring section measures the optical characteristics of a composite optical system provided by combining together the evaluating corrective optical system and the manufactured lens. The evaluating section evaluates the manufactured lens according to measured results provided by measuring section.

Abstract: When it is detected that a tracking target disappears in an image range in the course of tracking the tracking target, which is a registration pattern selected as a target to be tracked from among registration patterns, an autofocus is disabled. Thereafter, the autofocus is kept being disabled even if it is detected that the tracking target having the selected registration pattern appears in the image range. Alternatively, when the tracking target disappears in the image range in the course of tracking the tracking target, the autofocus is disabled, and thereafter when the tracking target having the registration pattern appears in the image range, it is started to track the tracking target having the registration pattern.

Abstract: According to an aspect of the present invention, at least parts or all of the windows for tarry lamps are located in the outside of the front cover by constructing the front cover portion between the top face and left-hand side face of the front cover, and the front cover portion between the top face and right-hand side face of the front cover as the inclined planes respectively. That is, since the windows for tarry lamps are not covered by the front cover as conventional ones, visibility from the external improves.

Abstract: The present invention relates to an optical part holding member made of ceramic and a production method thereof, and provides an optical part holding member made of ceramic such that a sintered body after processes of degreasing and sintering has small dimensional changes over dimensions of a mold, and a production method thereof. An example includes a lens holder to hold an optical part, made of a silicon nitride ceramic base composite material produced through a process in which silicon and nitrogen are reacted to be nitrided and contains silicon carbide and an iron compound.

Abstract: The present invention relates to an optical part holding member made of ceramic and a production method thereof, and provides an effective permeability to prevent dew condensation. The optical part holding member is made of a silicon nitride ceramic base composite material to hold an optical part, which is produced through a process of nitriding in which silicon is caused to react with nitrogen. By using the silicon nitride ceramic base composite material containing silicon carbide and an iron compound, an airflow volume of 50 ml or more per minute is achieved in an effective airflow area of 1.5 cm2 when an air pressure is added with a pressure difference of 0.4 MPa between both surfaces of a sample of the silicon nitride ceramic base composite material having 1 mm thickness, and the optical part holding member having effective permeability to prevent dew condensation is obtained.

Abstract: An endoscope apparatus comprises: an endoscope comprising an imaging device that forms a color image signal of a body to be observed; a storage portion that stores matrix data regarding a wavelength range in which a spectral image is constituted; a spectral image forming circuit that conducts matrix calculation based on the color image signals by using the matrix data of the storage portion and forms a spectral image of a selected wavelength range; and a wavelength selecting section that selects the wavelength range of the spectral image formed by the spectral image forming circuit through a continuous changeover or a step-wise changeover.

Abstract: An autofocus adapter is provided and includes an imaging adapter optical system placed on an optical axis of an imaging lens when the autofocus adapter is attached, and a focus state detection adapter optical system placed on an optical axis different from the optical axis of the imaging lens when the autofocus adapter is attached. The imaging adapter optical system has a light split prism for splitting subject light passing through the imaging lens into imaging subject light and the focus state detection subject light, a first lens group having a negative power as a whole and placed on the object side with respect to the light split prism, and a second lens group having a positive power as a whole and placed on the image side with respect to the light split prism. The focus state detection adapter optical system has a positive lens group having the same lens configuration as the second lens group in the imaging adapter optical system.

Abstract: A wide-angle imaging lens is provided and includes: a first lens, a second lens, and a third lens in this order from the object side. The first lens is a negative meniscus and has a convex surface on the object side; the second lens, at least one surface of which is an aspherical surface; and the third lens is a positive lens and has a convex surface on the image side and at least one surface of the third lens is an aspherical surface. The first len is made of a material having an Abbe number of 40 or more and the third lens is made of a material having an Abbe number of 50 or more. An aperture stop is disposed between the second lens and the third lens.

Abstract: A curve representing a characteristic of a blue-light reflecting dichroic film DB and a curve representing a characteristic of a red-light reflecting dichroic film DR are configured to have shapes that track an ideal spectral characteristic of green. Accordingly, it is possible to obtain a characteristic approximated to the ideal spectral characteristic without using a trimming filter having a dichroic film in an exiting surface of a prism. Since it is not necessary to use the trimming filter having the dichroic film, it is possible to prevent ghost and flare from occurring due to the dichroic film of the trimming filter. Accordingly, it is possible to embody an imaging apparatus having the ideal spectral characteristic with ghost and flare being reduced.

Abstract: An imaging device makes camera shake compensation by relatively moving an imaging optical system and an imaging element in directions perpendicular to an optical axis direction. The imaging device includes a first actuator that relatively moves the imaging optical system and the imaging element in a first direction perpendicular to the optical axis direction; a second actuator that relatively moves the imaging optical system and the imaging element in a second direction which is perpendicular to the optical axis direction and which intersects the first direction; and a first moving member to which the second actuator is attached, the first moving member that is moved together with the second actuator in the first direction by an action of the first actuator. The first actuator and the second actuator 6 are disposed to form a T shape.

Abstract: An endoscopic flow-passage confluent structure that connects a gas-feed tube and a liquid-feed tube provided in an endoscope to a confluent tube communicating with an ejection nozzle arranged at a tip of an insertion portion of the endoscope and for ejecting a cleaning fluid toward a viewing window of the endoscope, the structure comprising: (i) a passage connection member having one end opened with two upstream-passage receiving bores in which the gas-feed and liquid-feed tubes are respectively inserted and fixed, other end opened with one downstream-passage receiving bore, and an intermediate region that communicates the upstream-passage receiving bores with downstream-passage receiving bore and comprises a passage confluent space having a diameter increasing in a taper-form in a direction of from the downstream-passage receiving bore toward the upstream-passage receiving bores; and (ii) a coupler pipe having one end connected to the downstream-passage receiving bore and other end connected with a base of t