Abstract: A photolithographic etching process for accurately and uniformly fabricating wire screen disks of varying complex geometries for cryogenic cooler regenerators. The photolithographic etching process includes the steps of applying a photoresist to a sheet of wire screen, developing the photoresist in the form of one or more desired disk shapes, and then etching the developed sheet of wire screen to form the wire screen disks. The etching process of the present invention produces wire screen disks with solid edges, thus ensuring that the wire screen disks fit properly in the regenerator. Also, these edges have no loose or bent wires which can break off and potentially damage the compressor and other moving parts of the cryogenic cooler. The etching process of the present invention can be used to fabricate wire screen disks with varying complex geometries, thus allowing for the construction of cryogenic coolers having complex, but more efficient, configurations.

Abstract: A high-power semiconductor laser diode that employs a lateral antiresonant reflecting optical waveguide for generating a single-mode laser beam having an aperture spot size on the order of 4 to 8 microns. The lateral antiresonant reflecting optical waveguide is a negative-index waveguide or antiguide that operates in an antiresonance condition for the fundamental lateral mode, but not for the higher-order lateral modes. Consequently, the fundamental lateral mode is reflected by the lateral waveguide while the higher-order lateral modes are allowed to leak out. This provides strong discrimination between the fundamental lateral mode and the higher-order lateral modes in order to generate a single-mode laser beam having a large aperture spot size. The lateral waveguide also provides good lateral mode stability due to the large negative step in the waveguide index of refraction.