Abstract: A miniature laser cavity in which a solid-state lasing gain element and a Q-switch have respective end surfaces at substantially the Brewster angle, parallel to and facing each other, and separated by a narrow gap occupied by a transparent low-index-of-refraction material.

Abstract: An interface module for coupling a VMEbus channel to a Universal Common Data Point channel and exchanging data signals in either direction. The module responds to protocol handshake signals from the originating channel, accepts a multi-word message-block, and provides handshake signals to notify the destination channel of message to be delivered. The module then transfers the message-block to the destination channel.

Abstract: A polarographic oxygen detection cell of the type having concentric coplanar electrodes. The cell achieves more consistent and predictable operation by using electrode insulators to prevent electrochemical reaction between the areas of high charge density on the cathode and anode conduction disk and those portions of the electrolyte in which increased ion concentration has been attracted by this high charge density, and using the OH.sup.- based electrolyte and a carbon anode so that the reaction at the anode produces gas which can be bled off to avoid altering the composition of the anode or electrolyte.