Abstract: An imaging element unit includes an imaging element configured to include an imaging surface having a plurality of R pixels, G pixels and B pixels, and an infrared cut filter configured to be placed in a position immediately in front of the imaging surface, wherein the transmittance characteristics of the infrared cut filter is determined so that an RGB combined relative sensitivity which is a combined value of unique sensitivities of the R pixels, the G pixels and the B pixels and a relative sensitivity of the imaging surface determined by the transmittance characteristics of the infrared cut filter show each of the following sensitivities with the respect to each of the following wavelengths longer than 600 nm.

Abstract: A lens unit includes at least three lenses that are laminated and received in a lens barrel. The lenses include a first lens, a second lens, and a third lens that are laminated from the side of an object in this order. The first lens includes a first contact face that is formed at an outer peripheral portion thereof and comes in contact with the second lens, and a first opposite surface that is formed at an inner peripheral portion of the first contact face, is spaced from the second lens, and faces the second lens. The second lens includes a second contact face that is formed at a position closer to the center of the second lens than the first contact face and comes in contact with the third lens, and a second opposite surface that is formed at an outer peripheral portion of the second contact face, is spaced from the third lens, and faces the third lens.

Abstract: A lens unit includes at least three lenses that are laminated and received in a lens barrel. The lenses include a first lens, a second lens, and a third lens that are laminated from the side of an object in this order. The first lens includes a first contact face that is formed at an outer peripheral portion thereof and comes in contact with the second lens, and a first opposite surface that is formed at an inner peripheral portion of the first contact face, is spaced from the second lens, and faces the second lens. The second lens includes a second contact face that is formed at a position closer to the center of the second lens than the first contact face and comes in contact with the third lens, and a second opposite surface that is formed at an outer peripheral portion of the second contact face, is spaced from the third lens, and faces the third lens.

Abstract: A lens is fitted into a metal ring that covers the outer peripheral surface of the lens and can be soldered to a fixture member. The side cylindrical part of the metal ring is expanded toward the outer peripheral direction thereof by the pressure of the optical material put inside it, and, thus expanded, it defines the final dimension of the metal ring. One of the two openings formed on both sides of the side cylindrical part of the metal ring is so designed as to have a curving cylindrical part that extends from the side cylindrical part, and this curving cylindrical part is folded toward the optical functional face of the optical device to construct a metal ring-fitted optical device.

Abstract: A metal ring for an optical element that is served to cover a peripheral side surface of a lens and served to fix the lens to a mounting member by means of soldering is provided with a thin-wall sleeve a diameter of which is expanded toward a peripheral direction by means of pressure received from an optical material disposed inside the metal ring to thereby obtain a final peripheral side surface size, a thin-wall portion having an inside periphery near an extension of an inside peripheral surface of the thin-wall sleeve on one of apertures of the thin-wall sleeve, and a holding portion comprising a flange that projects from an edge of the aperture toward the aperture. A metal ring for an optical element, a method for fabrication of the optical element having the metal ring, and an optical element having a metal ring of the invention employ the abovementioned metal ring.

Abstract: A surface structure of a metallic body capable of properly maintaining the surface state of a gold layer by preventing diffusion of nickel under conditions of high temperature is provided. In the surface structure of a metallic body of a metal substrate plated with gold, the surface structure includes a nickel layer formed on the surface of the substrate, a barrier layer formed from one or more elements selected from Group 8A of the periodic table formed on the surface of the nickel layer, and a gold layer formed on the surface of the barrier layer.

Abstract: A lens is fitted into a metal ring that covers the outer peripheral surface of the lens and can be soldered to a fixture member. The side cylindrical part of the metal ring is expanded toward the outer peripheral direction thereof by the pressure of the optical material put inside it, and, thus expanded, it defines the final dimension of the metal ring. One of the two openings formed on both sides of the side cylindrical part of the metal ring is so designed as to have a curving cylindrical part that extends from the side cylindrical part, and this curving cylindrical part is folded toward the optical functional face of the optical device to construct a metal ring-fitted optical device.

Abstract: A beam-splitting/coupling apparatus comprises first and second frame member which each have a contact surface and a beam guide path. An optical filter is provided between the contact surfaces with the front and rear surfaces of the optical filter held by the first and second frame members respectively. The first and second frame members are held in a case by external flexible forces. A beam propagates from the beam guide path of the first frame member to the beam guide path of the second frame member by way of the optical filter. As a result, the optical filter can be installed firmly with ease. In addition, the effect of the installed optical filter on optical performance can be reduced.

Abstract: A metal ring for an optical element that is served to cover a peripheral side surface of a lens and served to fix the lens to a mounting member by means of soldering is provided with a thin-wall sleeve a diameter of which is expanded toward a peripheral direction by means of pressure received from an optical material disposed inside the metal ring to thereby obtain a final peripheral side surface size, a thin-wall portion having an inside periphery near an extension of an inside peripheral surface of the thin-wall sleeve on one of apertures of the thin-wall sleeve, and a holding portion comprising a flange that projects from an edge of the aperture toward the aperture. A metal ring for an optical element, a method for fabrication of the optical element having the metal ring, and an optical element having a metal ring of the invention employ the abovementioned metal ring.

Abstract: A diaphragm structure is provided at an outer edge portion on an incident side of a lens which converges a collimated incident light and outputs the converged light, the diaphragm structure being constructed so that a portion of the collimated incident light is reflected away from or toward an optical axis of the collimated light.

Abstract: A beam-splitting/coupling apparatus comprises first and second frame members which each have a contact surface and a beam guide path. An optical filter is provided between the contact surfaces with the front and rear surfaces of the optical filter held by the first and second frame members respectively. The first and second frame members are held in a case by external flexible forces. A beam propagates from the beam guide path of the first frame member to the beam guide path of the second frame member by way of the optical filter.

Abstract: An insertion hole for inserting an optical fiber is formed at a case, and then a resilient leaf spring and an operating button are stored in the case. The leaf spring is comprised of a through-pass hole formed at the central part of the leaf spring in correspondence with the insertion hole, a plurality of resilient lock claws extended from the circumferential edge of the through-pass hole toward the center thereof, and a groove recessed from a part of the circumferential edge in an outward direction. The operating button is provided with a stem of which part can be fed into or out of the case, the stem abutted against both edges of the groove is pushed under an operation of the stem, thereby a held state of the lock claws against the optical fiber can be released indirectly.