Abstract: An optical fiber collimator including a microlens array and single mode optical fibers. Microlens elements are formed in two surfaces of the transparent substrate. Two opposing microlens elements each function as a collimator lens. The single mode optical fiber is optically coupled to the collimator lens.

Abstract: An optical fiber collimator including a microlens array and single mode optical fibers. Microlens elements are formed in two surfaces of the transparent substrate. Two opposing microlens elements each function as a collimator lens. The single mode optical fiber is optically coupled to the collimator lens.

Abstract: A light source-optical fiber coupler constituted by: a light source (such as a semiconductor laser chip 10); and a gradient index rod lens 14 for coupling diffuse luminous flux emitted from the light source to an end surface of an optical fiber (such as a single mode optical fiber 16). The gradient index rod lens has a light source side end surface shaped like a convex spherical surface, and an optical fiber side end surface shaped like a flat surface. The gradient index rod lens is retained by the housing in the condition that the light source (laser chip) and the gradient index rod lens are disposed close to each other. The distance between a surface of the laser chip and an end surface of the gradient index rod lens is preferably selected to be not larger than 0.3 mm and more preferably in a range of from about 0.2 mm to about 0.25 mm.

Abstract: A method that accurately cuts mother rod lenses and increases production yield. The method includes arranging the mother rod lenses such that the optical axes of the mother rod lenses are parallel to one another, forming a lens block having perpendicular first and second side surfaces to integrally hold the predetermined mother rod lenses, arranging the lens block at a predetermined position, emitting laser beams respectively toward the first and second side surfaces, receiving reflection lights of the laser beams with first and second screens, respectively, adjusting the perpendicularity of the side surfaces relative to a cutting surface of the cutter such that the reflection lights of the side surfaces hit base positions on the first and second screen, and cutting the lens block and the mother rod lenses with the cutter to produce a plurality of rod lenses.

Abstract: A compact gradient index rod lens that can be manufactured without decreasing the amount of incident light. The gradient index rod lens includes a lens body radially distributing refractive indexes. The lens body has a cross sectional outline formed by removing at least part of a peripheral portion of an original lens body.

Abstract: A rod lens manufacturing method having satisfactory machining accuracy and enabling mass production. In the method, lens assembly sheets, each holding at least a row of rod lenses, are prepared. The lens assembly sheets are then arranged on holding surfaces defined on a jig. The holding surfaces are inclined relative to a reference surface of the jig by a predetermined angle. Each of the lens assembly sheet is clamped so that optical axes of the rod lenses are inclined relative to a direction perpendicular to the reference surface by that predetermined angle. The lens assembly sheets are then ground and polished.

Abstract: A light source-optical fiber coupler constituted by: a light source (such as a semiconductor laser chip 10); and a gradient index rod lens 14 for coupling diffuse luminous flux emitted from the light source to an end surface of an optical fiber (such as a single mode optical fiber 16). The gradient index rod lens has a light source side end surface shaped like a convex spherical surface, and an optical fiber side end surface shaped like a flat surface. The gradient index rod lens is retained by the housing in the condition that the light source (laser chip) and the gradient index rod lens are disposed close to each other. The distance between a surface of the laser chip and an end surface of the gradient index rod lens is preferably selected to be not larger than 0.3 mm and more preferably in a range of from about 0.2 mm to about 0.25 mm.

Abstract: A rod lens manufacturing method having satisfactory machining accuracy and enabling mass production. In the method, lens assembly sheets, each holding at least a row of rod lenses, are prepared. The lens assembly sheets are then arranged on holding surfaces defined on a jig. The holding surfaces are inclined relative to a reference surface of the jig by a predetermined angle. Each of the lens assembly sheet is clamped so that optical axes of the rod lenses are inclined relative to a direction perpendicular to the reference surface by that predetermined angle. The lens assembly sheets are then ground and polished.

Abstract: A compact refractive index distribution lens that can be manufactured without decreasing the amount of incident light. The refractive index distribution lens includes a lens body radially distributing refractive indexes. The lens body has a cross sectional outline formed by removing at least part of a peripheral portion of an original lens body.

Abstract: A method that accurately cuts mother rod lenses and increases production yield. The method includes arranging the mother rod lenses such that the optical axes of the mother rod lenses are parallel to one another, forming a lens block having perpendicular first and second side surfaces to integrally hold the predetermined mother rod lenses, arranging the lens block at a predetermined position, emitting laser beams respectively toward the first and second side surfaces, receiving reflection lights of the laser beams with first and second screens, respectively, adjusting the perpendicularity of the side surfaces relative to a cutting surface of the cutter such that the reflection lights of the side surfaces hit base positions on the first and second screen, and cutting the lens block and the mother rod lenses with the cutter to produce a plurality of rod lenses.

Abstract: A rod lens made of a transparent cylindrical medium having a refractive index distribution in the radial direction is used as a graded index lens. An object surface and an image surface are arranged on both sides of the rod lens. A first surface of the lens is a convex spherical surface, and a second surface of the lens is a planar surface, and the lens is arranged so that the convex spherical surface faces the object surface, and the planar surface faces an image surface. The equations1.0.ltoreq.R/r.sub.0 .ltoreq.1.6, andR/f.ltoreq.1.2are satisfied, wherein r.sub.0 is a radius of a portion of the rod lens that operates as a lens, measured from an optical axis of the lens, R is a curvature radius of the convex spherical surface, and f is a focal length of the rod lens. Thus, an object lens system with a large NA, that is smaller and lighter, while keeping the number of parts to a minimum, can be provided.

Abstract: This invention relates to a method of performing an ion exchange of optical glass to produce an axial gradient index material having a good linear distributiion by bringing a glass body containing a monovalent cation component into contact with a medium containing a monovalent cation component and exchanging these cation components under a predetermined condition.