Abstract: A method and apparatus for automatically testing chemical and ionic sensing electronic circuits is provided. A fluid used in testing is placed in a hollow pipette with at least one open end. The open end of the pipette is applied directly against a sensing layer on the sensing electronic circuit forming a leakproof seal. Alternatively, a flow-through type fluid container is used and is advantageously applied with gas measurements. Test electronics are provided to compile and analyze the performance of various sensing layers. Aligning means automatically select a sensing electronic circuit and position the circuit such that the holding device can be urged against the sensing layer automatically.

Abstract: An improved electronic particle counter is described in which the electrodes and at least part of the signal processing circuitry are integrally formed on the pane in which the orifice is located. The pane is formed from a wafer of sapphire of the grade customarily used in the manufacture of silicon-on-sapphire integrated circuits. A silicon layer is first formed epitaxially on one side of the wafer and integrated circuits are then formed in the silicon layer using conventional photolithographic techniques. Illustratively, the integrated circuits provide the same particle counting and particle sizing functions that are available in separate packages with state-of-the-art particle counters. An electrode is formed on the same side of the wafer as the integrated circuit by converting some of the epitaxial silicon to a conductive polysilicon or by depositing a metallic layer; and the electrode is connected to the signal input lead of the integrated circuit.

Abstract: An ambient sensing device is described especially suited to the sensing of a variety of ambient parameters. Photolithographic techniques are used to pattern a multiplicity of sensitive layers on a single monolithic substrate taking into account the wide range of plastic, gelatinous and ceramic materials to be patterned and the problems of their cross-contamination when in contact.

Abstract: A device is disclosed for intraoral ambient sensing. In this embodiment, the device comprises a removable oral (Hawley) appliance containing a number of chemically sensitive electrodes and a common reference electrode at the chemical sensing sites and a telemetry unit plus power pack for signal transmission. This device may also be used to monitor non-chemical parameters, notably pressure, temperature, and flow. In this embodiment, the removable oral (Hawley) appliance contains a number of sensors to monitor the parameter of interest. For example, a pressure sensor configured as an artificial uvula and mounted to the oral (Hawley) appliance emulates actual uvula pressure events. To monitor chewing events, a pressure sensor is mounted to the oral (Hawley) appliance in such a manner that it is optimally located at an open bite location of the mouth. In either embodiment, a telemetry unit mounted to the oral (Hawley) appliance transmits the intraoral ambient information as radio frequency signal bursts.

Abstract: A device for the measurement of ionic and gas species at high temperatures. Platinum metal oxides are used for the electrical signal paths between electrical elements on the device to make the device particularly adaptable to high temperature measurement applications. Chemically sensitive composite structures may be hardened for high temperature applications by mixing polyimide with the materials normally used in the outer layer of such structure.

Abstract: A conductive metal oxide electrode can be calibrated by immersing the electrode and a reference electrode in a solution of known pH and applying to them a setting potential which is approximately equal to the steady state potential that would be observed for that electrode with respect to the reference electrode in a solution of that value of pH.