Fused SiO2 has been used as a new noncrystalline host for the fabrication of two types of neodymium‐doped room‐temperature lasers, one of which operates at 1.06‐μm and the other at 1.08‐μm wavelength. The lasers have the geometry of clad optical fibers, with active cores as small as 15‐μm diameter by 1‐cm length. They are end pumped at 0.590 and 0.5145 μm with a pulsed dye laser and an argon ion laser, respectively. Thresholds as low as 1–2 mW of absorbed pump power in a 40‐μm‐diam core have been obtained, and eventual pumping with high‐radiance semiconductor optical sources appears feasible.

Neodymium‐doped silica lasers in end‐pumped fiber geometry

A glass composition for chemical tempering includes oxides in wt % ranges of: SiO 2 60 to 75; Al 2 O 3 18 to 28; Li 2 O 3 to 9; Na 2 O 0 to 3; K 2 O 0 to 0.5; CaO 0 to 3; MgO 0 to 3; ZrO 2 0 to 3; where MgO+CaO is 0 to 6 wt %; Al 2 O 3 +ZrO 2 is 18 to 28 wt %, and Na 2 O+K 2 O is 0.05 to 3.00 wt %. The glass has a log 10 viscosity temperature in the temperature range of 1328° F. (720° C.) to 1499° F. (815° C.); a liquidus temperature in the temperature range of 2437° F. (1336° C.) to 2575° F. (1413° C.), and a log 7.6 softening point temperature in the temperature range of 1544° F. (840° C.) to 1724° F. (940° C.). The chemically tempered glass has, among other properties, an abraded modulus of rupture of 72 to 78 KPSI, and a modulus of rupture of 76 to 112 KPSI.

Lithia-alumina-silica containing glass compositions and glasses suitable for chemical tempering and articles made using the chemically tempered glass

Keywords: flat panel displays ; compound eye ; microlenses ; micro-optics ; multi-aperture imaging ; optical images ; photolithography ; photoresists Reference EPFL-ARTICLE-183166 Record created on 2013-01-17, modified on 2017-05-10

https://doc.rero.ch/record/8481/files/V_lkel_Reinhard_-_Microlens_array_imaging_system_for_photolithography_20071211.pdf

Microlens array imaging system for photolithography

Disclosed herein is an apparatus of the type for forming a nonwoven web from a fiber forming thermoplastic polymer resin which includes a reservoir for supplying a quantity of melted fiber forming thermoplastic resin, a pump for pumping the molten resin to a fiber forming die, and a die for forming a discrete resin stream to flow therefrom. The die includes a first fluid passageway for forming a stream of fluid, such as air, in contact with and substantially surrounding the formed flow of resin for a predetermined distance within the die and a fluid interrupt system for selectively cycling the flow of resin on and off and clearing the resin from the fiber forming die. A receiving belt collects the fibers formed from the resin flow beyond the first fluid passageway spaced at a predetermined distance from the die.

Apparatus for forming a nonwoven web

Neodymium-Doped Fiber Lasers: Room Temperature cw Operation with an Injection Laser Pump

Optical device for transmitting an image wherein a number of optical fibers are disposed in such a manner that they are arranged neatly in the same relative position among them, at least, both ends thereof, each of said fibers having such a refractive index distribution as to substantially satisfy the equation n = N (1 - ar2) IN A CROSS SECTION THEREOF, WHERE N is a refractive index at a center, n is a refractive index at a distance r from the center, and a is a positive constant, whereby light due to an object placed at one end of said fibers forms an image of the object at the other end thereof.

Image transmitter formed of a plurality of graded index fibers in bundled configuration

By heat treating a glass member containing at least one kind of cation to constitute a modifying oxide in contact with a source of another kind of cation to cause ion substitution, a light-conducting glass structure can be produced to have a refractive index distribution wherein the index varies progressively transversely to the intended light path, which is thereby bent toward the direction of increase of the index, such a light-conducting glass structure is not accompanied by differences or lagging of phase velocities of conducted light rays, spreading of the light flux width, and reflection losses.

Light-conducting glass structures

In a method for producing optical glass fibers which comprises co-spinning glass melts of different kinds through coaxially disposed discharge nozzles of a multimember crucible composed of two or more crucible members having a discharge nozzle at their bottom, the improvement wherein the outermost nozzle has a length of at least 30 mm and is heated so that at least a part of it is maintained at a temperature equal to, or higher than, the temperature of the crucible thereby to increase the speed of spinning; and a high-speed spinning furnace used therefor.

Production of optical glass fibers

A transparent glass body having a light-focusing effect and a refractive index decreasing progressively from its centerline outward and containing readily reducible metal oxides in at least the outer peripheral part thereof is caused to contact a gas having a reducing effect thereby to reduce the metal oxides and form a light-absorbent layer of metal colloid in the outer peripheral part.

Ken Koizumi

Papers

Image transmitter formed of a plurality of graded index fibers in bundled configuration

Light-conducting glass structures

Production of optical glass fibers

Light-conducting glass structure having a peripheral light-absorbent layer

Method of producing light-conducting glass structure