Abstract: An endoscope system includes: a generating means generating a compositing mask that serves as compositing ratios of the corresponding pixels between a pair of images acquired by simultaneously imaging two optical images having different focus positions, into which a subject image is divided on the basis of the ratios of contrasts; a correcting means subjecting compositing masks generated for pairs of images acquired in time series, to weighted averaging for respective pixels, thus generating a corrected mask; and an compositing means compositing the two images according to the corrected mask. The correcting means subjects the compositing masks to weighted averaging by performing weighting such that the percentage of the past compositing masks is higher at pixels constituting a static area and an area having contrast lower than a threshold than at pixels constituting a moving-object area or an area having contrast equal to or higher than the threshold.

Abstract: This endoscope device can simplify the determination of the moving direction of a focusing lens, and can improve the accuracy of auto focusing. The endoscope has the following elements: an optical system having a focusing lens; a lens moving unit which moves the focusing lens along an optical axis thereof; an image capturing unit which obtains an optical image of an object from the optical system as a plurality of images each of which has a different focal position from each other; a moving direction determining section which determines whether to change the observation depth on the basis of the plurality of images, and determines a moving direction toward which the focusing lens is to be moved on the bases of the images; and a drive control unit which controls the lens moving unit to move the focusing lens toward a determined moving direction.

Abstract: Provided is a three-dimensional-endoscope optical system that is provided with two objective optical systems having optical axes, which are arranged with a spacing therebetween, and that satisfies the following conditions: 0.5 mm<OP<1.5 mm??(1); 3 mm<D<200 mm??(2); ?<10°??(3); and 110°<?<180°??(4), where OP is a spacing between the optical axes of optical members at the most distal ends of the objective optical systems, D is a depth of field, ? is an angle of convergence (inward angle) of the depth of field D when performing near-point observation, and ? is an angle of view of the objective optical systems.

Abstract: An endoscope system includes: a generating means generating a compositing mask that serves as compositing ratios of the corresponding pixels between a pair of images acquired by simultaneously imaging two optical images having different focus positions, into which a subject image is divided on the basis of the ratios of contrasts; a correcting means subjecting compositing masks generated for pairs of images acquired in time series, to weighted averaging for respective pixels, thus generating a corrected mask; and an compositing means compositing the two images according to the corrected mask. The correcting means subjects the compositing masks to weighted averaging by performing weighting such that the percentage of the past compositing masks is higher at pixels constituting a static area and an area having contrast lower than a threshold than at pixels constituting a moving-object area or an area having contrast equal to or higher than the threshold.

Abstract: This endoscope device can simplify the determination of the moving direction of a focusing lens, and can improve the accuracy of auto focusing. The endoscope has the following elements: an optical system having a focusing lens; a lens moving unit which moves the focusing lens along an optical axis thereof; an image capturing unit which obtains an optical image of an object from the optical system as a plurality of images each of which has a different focal position from each other; a moving direction determining section which determines whether to change the observation depth on the basis of the plurality of images, and determines a moving direction toward which the focusing lens is to be moved on the bases of the images; and a drive control unit which controls the lens moving unit to move the focusing lens toward a determined moving direction.

Abstract: An endoscope includes an objective optical system at a distal end of an inserted portion to acquire a subject image; a part that splits the subject image into two optical images focused differently; an imaging device that acquires two images by simultaneously capturing the optical images arranged on an imaging surface; and a part for cutting out at least abutting portions of the optical images on the imaging device, wherein A+B>C+D, where A is half the maximum length of light-receiving regions for the optical images at the imaging surface; where TW is an entry angle at the imaging surface when A is at the maximum image height and d is an optical-path-length difference between the optical images, B=d×tan TW; C is half the length of the light-receiving regions in a direction of the optical images arranged on the imaging surface; and D is a distance between the two light-receiving regions.

Abstract: Provided is an image-acquisition device including an image acquisition element; a prism that is secured to the image-acquisition element and that has an entrance surface through which light enters from a direction that intersects an optical axis of the image-acquisition element, an exit surface that is substantially parallel to an image-acquisition surface of the image-acquisition element, and a reflection surface that deflects the light that has entered through the entrance surface toward a direction that is parallel to the optical axis of the image-acquisition element; and a cover member that is secured at a position that covers the reflection surface of the prism and that has an outer surface that is substantially parallel to the image-acquisition surface, wherein an end surface of the cover member closer to the entrance surface is disposed at a position protruding beyond the entrance surface.

Abstract: There is provided an endoscope apparatus capable of stably and precisely measuring a distance to an object by suppressing variations in measured values of the distance to the object depending on the presence or absence of pigment dispersion or the like and capable of enabling observations based on clear and high quality images. The endoscope apparatus includes an optical system that condenses light from an object and simultaneously forms two optical images having the same characteristics with difference only in focal point; an imaging element that captures the two optical images formed by the optical system and acquires two images; and a calculation unit that obtains distance information corresponding to a distance to the object based on a contrast ratio of the two images in a range in which the two images acquired by the imaging element have a common contrast.

Abstract: An endoscope includes an objective optical system at a distal end of an inserted portion to acquire a subject image; a part that splits the subject image into two optical images focused differently; an imaging device that acquires two images by simultaneously capturing the optical images arranged on an imaging surface; and a part for cutting out at least abutting portions of the optical images on the imaging device, wherein A+B>C+D, where A is half the maximum length of light-receiving regions for the optical images at the imaging surface; where TW is an entry angle at the imaging surface when A is at the maximum image height and d is an optical-path-length difference between the optical images, B=d×tanTW; C is half the length of the light-receiving regions in a direction of the optical images arranged on the imaging surface; and D is a distance between the two light-receiving regions.

Abstract: Provided is a three-dimensional-endoscope optical system that is provided with two objective optical systems having optical axes, which are arranged with a spacing therebetween, and that satisfies the following conditions: 0.5 mm<OP<1.5 mm??(1); 3 mm<D<200 mm??(2); ?<10°??(3); and 110°<?<180°??(4), where OP is a spacing between the optical axes of optical members at the most distal ends of the objective optical systems, D is a depth of field, ? is an angle of convergence (inward angle) of the depth of field D when performing near-point observation, and ? is an angle of view of the objective optical systems.

Abstract: A capsule endoscope is disclosed that includes first and second objective optical systems for forming images of objects viewed in the capsule insertion direction and in the opposite direction on separate areas of one plane where an image pickup surface of an image pickup device is located. The capsule endoscope also includes illuminators for illuminating the objects, and a deflector or deflectors, such as reflecting prisms, for folding light from the objective optical systems to the image pickup surface so that the image pickup surface is parallel to the capsule insertion direction. The objective optical systems are retrofocus optical systems. The illuminators may have emission surfaces centered on the centers of spheres defined by dome-shaped transparent covers aligned along a central axis of the capsule endoscope. The objective optical systems, the deflector or deflectors, and the image pickup device are arranged completely off the central axis of the capsule endoscope.

Abstract: There is provided an endoscope apparatus capable of stably and precisely measuring a distance to an object by suppressing variations in measured values of the distance to the object depending on the presence or absence of pigment dispersion or the like and capable of enabling observations based on clear and high quality images. The endoscope apparatus includes an optical system that condenses light from an object and simultaneously forms two optical images having the same characteristics with difference only in focal point; an imaging element that captures the two optical images formed by the optical system and acquires two images; and a calculation unit that obtains distance information corresponding to a distance to the object based on a contrast ratio of the two images in a range in which the two images acquired by the imaging element have a common contrast.

Abstract: An image forming lens includes a lens element having a flange part that is integral with the lens element. When assembled with an image pickup element to form an image pickup module, an outside perimeter portion of the lens element having a flange part, at a region nearest an image pickup element, is inclined so that outer diameters thereof increase when successively measured at positions nearer to the image pickup element. A frame of the image forming lens according to the invention has an inclined portion on the object side with an outer diameter that becomes smaller when successively measured nearer the object side. Satisfying one or more conditions insures accuracy in assembly and that there will be sufficient room near the object side outside the inclined portion to mount a light source, such as an LED, without having to increase the maximum outer diameter of the image pickup module.

Abstract: An image pickup module comprises a lens assembly including a lens having a flange part, and a frame component for shading a circumferential surface excluding a neighborhood of a top portion of the flange part in the lens; an image pickup element which the top portion of the flange part touches; and an illumination element arranged around the lens assembly and the image pickup element. The image pickup module is constituted so that exit light from a luminescent surface of the illumination element does not reach directly to an exposed portion that is not shaded by the frame component of the flange part.

Abstract: An imaging optical system includes a spherical or nearly spherical viewing port, an objective lens that includes an aspheric surface and is formed as a single lens element, and a solid-state image sensor that receives an image formed by the imaging optical system. Specified conditions are satisfied by the imaging optical system and the objective lens so that an in-focus image having low distortion, sufficient contrast, and formed by light rays of restricted angles of incidence is formed even for an object in contact with the viewing port. The specified conditions relate to features of the imaging optical system such as focal length and f-number of the imaging optical system, astigmatism and distortion of the imaging optical system, and pixel pitch of the solid-state image sensor. An endoscope that includes the imaging optical system is also disclosed.

Abstract: An illumination optical system for endoscopes, which is used by combining the llumination optical system with an objective optical system, where the objective optical system can observe a predetermined area at least ranging from the lateral direction to the backward direction with respect to the longitudinal direction of an endoscope and across the range of 180 degrees or more in the circumferential direction of the endoscope, and which is provided with an illumination optical system capable of radiating light to the predetermined area which can be observed by the objective optical system, is formed in such a way that illumination light becomes central darkening along the longitudinal direction of the endoscope and across the range of 180 degrees in the circumferential direction of the endoscope which can be observed by the objective optical system and that the illumination optical system has a luminous intensity distribution characteristic in which the central-darkening illumination light is radiated to the

Abstract: An imaging optical system includes a spherical or nearly spherical viewing port, an objective lens that includes an aspheric surface and is formed as a single lens element, and a solid-state image sensor that receives an image formed by the imaging optical system. Specified conditions are satisfied by the imaging optical system and the objective lens so that an in-focus image having low distortion, sufficient contrast, and formed by light rays of restricted angles of incidence is formed even for an object in contact with the viewing port. The specified conditions relate to features of the imaging optical system such as focal length and f-number of the imaging optical system, astigmatism and distortion of the imaging optical system, and pixel pitch of the solid-state image sensor. An endoscope that includes the imaging optical system is also disclosed.

Abstract: An imaging optical system includes a spherical or nearly spherical viewing port, an objective lens that includes an aspheric surface and is formed as a single lens element, and a solid-state image sensor that receives an image formed by the imaging optical system. Specified conditions are satisfied by the imaging optical system and the objective lens so that an in-focus image having low distortion, sufficient contrast, and formed by light rays of restricted angles of incidence is formed even for an object in contact with the viewing port. The specified conditions relate to features of the imaging optical system such as focal length and f-number of the imaging optical system, astigmatism and distortion of the imaging optical system, and pixel pitch of the solid-state image sensor. An endoscope that includes the imaging optical system is also disclosed.

Abstract: An imaging module for endoscopes includes a convex lens and an image sensor in which mutual positions are fixed and a plurality of optical modules that are selectively mountable with respect to the fundamental module so that the observation condition is switched in accordance with an optical module selectively mounted. The imaging module for endoscopes is constructed so that when each of the optical modules is mounted to the fundamental module, an image position and an angle of oblique incidence of light of an observation image on the image sensor are practically unchanged.

Abstract: A TV observation system for an endoscope including an endoscope and a small-sized light source unit. The endoscope can be structurally separated into an insertion part and a proximal holding part continuously extending from the insertion part. The endoscope can include a light guide arranged from a distal end of the insertion part through the proximal holding part. The proximal holding part can be provided with a light guide joint section where an entrance end face of the light guide is fixed. The small-sized light source unit can be constructed and arranged to be removably connected with the light guide joint section. The small-sized light source unit can include a plurality of small-sized LEDs, a batter configured to power the plurality of LEDs, and a compounding optical system configured to compound light emitted by the plurality of small-sized LEDs.