Abstract: In an endoscope objective lens which includes a reflective member that bends an optical path substantially at a right angle inserted between the last lens surface and an image sensor disposed on the image plane, the effective diameter of the last lens surface is made smaller than the size of the image sensor in a direction corresponding to the optical path bending direction and the endoscope objective lens is made so as to satisfy a conditional expression given below. h1<V+0.

Abstract: In an endoscope objective lens which includes a reflective member that bends an optical path substantially at a right angle inserted between the last lens surface and an image sensor disposed on the image plane, the effective diameter of the last lens surface is made smaller than the size of the image sensor in a direction corresponding to the optical path bending direction and the endoscope objective lens is made so as to satisfy a conditional expression given below. h1<V+0.

Abstract: In an endoscope objective lens which includes a reflective member that bends an optical path substantially at a right angle inserted between the last lens surface and an image sensor disposed on the image plane, the effective diameter of the last lens surface is made smaller than the size of the image sensor in a direction corresponding to the optical path bending direction and the endoscope objective lens is made so as to satisfy a conditional expression given below. h1<V+0.

Abstract: An imaging optical system comprises a first lens group composed of a negative single lens, a second lens group composed of a positive lens element and a negative lens element attached together, an aperture stop, a third lens group composed of a positive lens element and a negative lens element attached together, and a fourth lens group composed of a negative single lens, in this order from an object side. Expressions 0.37<hF/IH<0.5 and 0.37<hR/IH<0.5 are satisfied where “IH” denotes a maximum image height on an image plane, “hF” denotes an incident height of a principal ray, directed to a position of the maximum image height on the image plane, at its entrance into the first lens group, and “hR” denotes an exit height of the principal ray at its exit from the fourth lens group.

Abstract: An imaging lens has a negative first-lens, a first-cemented-lens of a second-lens and a third-lens, a stop, a positive fourth-lens, and a second-cemented-lens of a fifth-lens and a sixth-lens in this order from an object-side. The first-lens has a plano-concave or meniscus shape with a concave image-side surface. One of the second-lens and the third-lens is a positive lens and the other one is a negative lens. An object-side surface of the fourth-lens is a flat surface or a surface with a curvature radius having an absolute value greater than that of its image-side surface. One of the fifth-lens and the sixth-lens is a positive lens and the other one is a negative lens.

Abstract: In an endoscope objective lens which includes a reflective member that bends an optical path substantially at a right angle inserted between the last lens surface and an image sensor disposed on the image plane, the effective diameter of the last lens surface is made smaller than the size of the image sensor in a direction corresponding to the optical path bending direction and the endoscope objective lens is made so as to satisfy a conditional expression given below. h1<V+0.

Abstract: The view finder includes an observation optical system for enlarged observation of information displayed on a display section. The observation optical system includes an optical path bending member for bending the optical path. The view finder is configured such that an angle formed between a principal ray of a maximum angle of view and the display section is in the range of 90±5 degrees.

Abstract: An imaging lens consists of a negative first-lens, a first-cemented-lens of a second-lens and a third-lens, a stop, a positive fourth-lens, and a second-cemented-lens of a fifth-lens and a sixth-lens in this order from an object-side. The first-lens has a plano-concave or meniscus shape with a concave image-side surface. One of the second-lens and the third-lens is a positive lens and the other one is a negative lens. An object-side surface of the fourth-lens is a flat surface or a surface with a curvature radius the absolute value of which is greater than that of its image-side surface. One of the fifth-lens and the sixth-lens is a positive lens and the other one is a negative lens. Formulas about the ratio of a back focus to a focal length in the entire system, and refractive indices and Abbe numbers of the positive and negative lenses in the first-cemented-lens are satisfied.

Abstract: The view finder includes an observation optical system for enlarged observation of information displayed on a display section. The observation optical system includes an optical path bending member for bending the optical path. The view finder is configured such that an angle formed between a principal ray of a maximum angle of view and the display section is in the range of 90±5 degrees.

Abstract: A capsule endoscope includes an image pickup optical system for imaging an object. The image pickup optical system satisfies a condition expressed by ?5??Zr/?Zp?5. Assuming ?max is a maximum half angle of view, ?Zr is a difference between a position of a real image surface with respect to light flux of 2?max and that with respect to light flux of ?max, and ?Zp is a difference between a paraxial image forming position of a first virtual object plane surface and that of a second virtual object plane surface. The first virtual object plane surface passes through an intersection point P1 of the object and principal rays of 2?max. The second virtual object plane surface passes through an intersection point of the object and principal rays of ?max. The first and second virtual object planes are vertical to the optical axis.

Abstract: An imaging optical system comprises a first lens group composed of a negative single lens, a second lens group composed of a positive lens element and a negative lens element attached together, an aperture stop, a third lens group composed of a positive lens element and a negative lens element attached together, and a fourth lens group composed of a negative single lens, in this order from an object side. Expressions 0.37<hF/IH<0.5 and 0.37<hR/IH<0.5 are satisfied where “IH” denotes a maximum image height on an image plane, “hF” denotes an incident height of a principal ray, directed to a position of the maximum image height on the image plane, at its entrance into the first lens group, and “hR” denotes an exit height of the principal ray at its exit from the fourth lens group.

Abstract: A finder apparatus superimposes, on an image formed by an observation optical system of a reverse-Galilean finder including an objective lens group and an eyepiece lens group, display on a display member arranged outside an optical path of the observation optical system by using an optical path combination member arranged between the objective lens group and the eyepiece lens group, thereby making a user observe the image on which the display is superimposed. The finder apparatus includes a target lens group that guides light from the display member, and which is provided in an optical path from the display member to the eyepiece lens group. Further, the focal length of the eyepiece lens group, and a combined focal length from the target lens group through the eyepiece lens group satisfy predetermined formulas.

Abstract: In an objective lens for an endoscope, the full angle of view exceeds 120 degrees, and a most-object-side surface of the objective lens is spherical. Further, the following condition formulas (1) and (2) are satisfied: 0.7<?8/?10<0.8??(1); and 5<R1/f<15??(2), where ?10: half angle of view corresponding to a maximum image height; ?8: half angle of view corresponding to an image height that is 80% of the maximum image height; R1: curvature radius of the most-object-side surface; and f: focal length of the entire system of the objective lens.

Abstract: A finder apparatus superimposes, on an image formed by an observation optical system of a reverse-Galilean finder including an objective lens group and an eyepiece lens group, display on a display member arranged outside an optical path of the observation optical system by using an optical path combination member arranged between the objective lens group and the eyepiece lens group, thereby making a user observe the image on which the display is superimposed. The finder apparatus includes a target lens group that guides light from the display member, and which is provided in an optical path from the display member to the eyepiece lens group. Further, the focal length of the eyepiece lens group, and a combined focal length from the target lens group through the eyepiece lens group satisfy predetermined formulas.

Abstract: To widen an angle of view and make an image surface coincide with the neighborhood of an image pickup surface over the whole angle of view. A capsule endoscope 10 includes an image pickup optical system 20 for capturing an image of an object surface 12 in the shape of concave hemisphere surface. The image pickup optical system 20 satisfies a condition expressed by ?5??Zr/?Zp?5. Here, when a maximum half angle of view is ?max, ?Zr denotes a difference between a position of a real image surface with respect to light flux of 2?max and that with respect to light flux of ?max, and ?Zp denotes a difference between a paraxial image forming position of a virtual object plane surface 24 and that of a virtual object plane surface 25. The virtual object plane surface 24 passes through an intersection point P1 of the object surface 12 and principal rays of 2?max, and is vertical to an optical axis XP.

Abstract: A first lens group having positive refractive power, a second lens group having negative refractive power, a third lens group having the negative refractive power, and a fourth lens group having the positive refractive power are included in order from an object side, and variation of magnification from a wide-angle end to a telephoto end is performed by monotonically moving the second lens group toward an image side and compensation of a fluctuation of an image surface resulting from the variation of magnification is performed by moving the third lens group. At least one positive lens having an optical material satisfying a conditional expressions is included in at least one of the first lens group G1 and the fourth lens group.

Abstract: An endoscope objective lens includes, in order from an object side, a negative first lens, a first cemented lens, an aperture diaphragm, a positive fourth lens and a second cemented lens. The negative first lens has a concave surface directed to an image side. The first cemented lens is formed by cementing a second lens and a third lens. One of the second and third lenses is positive and. The other is negative. The positive fourth lens includes a flat surface or a surface having a larger absolute value in radius of curvature, directed to the object side. The second cemented lens is formed by cementing a positive fifth lens and a negative sixth lens in order from the object side. The second cemented lens has a positive refractive power as a whole. The endoscope objective lens satisfies the following conditional expressions (1) and (2). f 2 × ? v 5 - v 6 ? ? R A ? × ( Bf + d 6 / n 6 ) > 10 ( 1 ) Bf / f > 2.

Abstract: In a surveillance camera 2, an optical system unit for use in imaging is provided with a first lens 7, a second lens 8, a third lens 9, and a fourth lens 10, and a subject image is formed on a photoelectric surface 12 of an imaging element through a cover glass 11. The third lens 9 is an optical lens made of a nanocomposite material of the invention in which inorganic fine particles are dispersed. A thin film layer 15 that blocks UV rays is formed on a light incident surface of the third lens 9. After passing through the first lens 7 and the second lens 8, UV rays contained in subject light are blocked by the thin film layer 15 and therefore cannot enter the third lens 9.

Abstract: In an objective lens for an endoscope, the full angle of view exceeds 120 degrees, and a most-object-side surface of the objective lens is spherical. Further, the following condition formulas (1) and (2) are satisfied: 0.7<?8/?10<0.8??(1); and 5<R1/f<15??(2), where ?10: half angle of view corresponding to a maximum image height; ?8: half angle of view corresponding to an image height that is 80% of the maximum image height; R1: curvature radius of the most-object-side surface; and f: focal length of the entire system of the objective lens.

Abstract: An electronic rubbed copy imaging system is provided and includes: a flat substrate; an imaging sheet; and a controlling portion that receives image data of the object read from the imaging sheet and applies a signal processing to the image data. The imaging sheet has: a plurality of light emitting elements that come close to an object and emit an illumination light to the object, and a plurality of light receiving elements that receives a reflected light of the illumination light from the object, and the light emitting elements and the light receiving elements are alternately aligned.