Abstract: According to this invention the argon gas laser for emitting monochromatic light at 4880 .ANG. is provided comprising an elongated envelope with a capillary filled mainly with argon gas, an optical resonator comprising a high reflectance multilayer mirror and an output coupling multilayer mirror facing each other and disposed along the optical axis of the envelope. A cathode electrode and an anode electrode are disposed within the envelope for discharging the gas. Each mirror comprising alternate stacked layers of relatively high refractive index materials and relatively low refractive index materials. The high reflective mirror having a high reflectance band with a center wavelength .lambda..sub.0 containing a laser wavelength .lambda..sub.L within said band which satisfies the following expression:.lambda..sub.0 +3/16.2.DELTA.g<.lambda..sub.L <.lambda..sub.0 +3/8.2.DELTA.gwhere 2.DELTA.g is a band width of the high reflectance band and .lambda..sub.L is selected to 4880 .ANG..

Abstract: A solar cell and a method of manufacturing the same are disclosed. The solar cell has a semiconductor substrate having a major surface for receiving light, a p-n junction for photovoltatic generation therein and a thin alumina coating layer on the major surface of the semiconductor substrate. The alumina coating layer includes H radicals and OH radicals.

Abstract: A patterned layer article for semiconductor devices or stripe filters of color television cameras characterized by using, as a base, a protective layer of an etching rate smaller than that of a thin layer for controlling the etching depth of the thin layer, and this protective layer, particularly consists of oxides of rare earth elements such as yttrium oxide, and scandium oxide.