Abstract: In a thermoelectric device, a thermoelectric element has one surface on a low temperature side and the other surface on a high temperature side. A member is attached to at least one of the low- and high-temperature-side surfaces of the thermoelectric element. A temperature detection element is provided between the member and the surface of the thermoelectric element to which the member is attached. A mirror surface state detection device is also disclosed.

Abstract: Very small projections (10-2) are arranged on a mirror surface (10-1) of a mirror (10). The shape of a projection (10-2) is not limited to a circular cone, but it can be a hollow-cylindrical shape, semispherical shape, or square prism shape, and also, it can be a polyhedron with many faces. With a reduction in temperature of the mirror (10), water vapor contained in a gas to be measured condenses on the mirror surface (10-1) of the mirror (10). In this case, because of the very small projections (10-2) on the mirror surface (10-1), the condensation is promoted by the projections (10-2) serving as the cores. This facilitates condensation even at low dew points and improves response. Further, the size of condensation products does not easily vary relative to variation in flow speed of the gas to be measured, and this makes equilibrium of condensation less likely to break, increasing measurement accuracy.

Abstract: The long-side surface of a triangular prism is a detection surface. The distal end portions of coaxial light-emitting/light-receiving optical fiber cables are joined to one short-side surface of the prism. A thermoelectric cooling element is mounted on the other short-side surface of the prism. A mirror is provided between the cooling surface of the thermoelectric cooling element and the short-side surface. When dew condensation occurs on the detection surface, part of light applied from an optical fiber on the light-emitting side onto the lower surface of the detection surface exits from the prism through the condensed dew. The specular reflection returns to the lower detection surface by a mirror surface and is specularly reflected again. The specular reflection then enters an optical fiber on the light-emitting side. Dew condensation on the detection surface is detected by a change in the intensity of light received through the optical fiber.

Abstract: A plurality of minute projections (10-2) are provided on a mirror surface (10-1) of a mirror (10). The shape of a projection (10-2) is not limited to a conical shape, and may be a cylindrical shape, semispherical shape, quadratic prism shape, and the like. Furthermore, the shape may be a polyhedral shape with many surfaces. With a reduction in the temperature of the mirror (10), water vapor contained in a gas to be measured condenses on the mirror surface (10-1). In this case, because of the minute projections (10-2) on the mirror surface (10-1) of the mirror (10), the condensation is promoted by the projections (10-2) serving as nuclei. This facilitates condensation even at low dew points and improves responsiveness. Further, the sizes of condensed dew drops do not easily vary relative to variation in the flow rate of the gas to be measured, and this makes the equilibrium state of condensation unlikely to break, increasing measurement accuracy.

Abstract: In a mirror surface state detection device, a light-emitting element obliquely irradiates the mirror surface of a mirror with light. A light-receiving element is arranged adjacent to the light-emitting element to have an optical axis almost parallel to that of the light-emitting element and a tilt angle almost equal to that of the light-emitting element and receives scattered light of the light emitted from the light-emitting element. A condensation detection unit detects the state on the mirror surface on the basis of the scattered light received by the light-receiving element. A moisture detection device is also disclosed.

Abstract: In a thermoelectric device, a thermoelectric element has one surface on a low temperature side and the other surface on a high temperature side. A member is attached to at least one of the low- and high-temperature-side surfaces of the thermoelectric element. A temperature detection element is provided between the member and the surface of the thermoelectric element to which the member is attached. A mirror surface state detection device is also disclosed.

Abstract: In a mirror surface state detection device, a light-emitting element obliquely irradiates the mirror surface of a mirror with light. A light-receiving element is arranged adjacent to the light-emitting element to have an optical axis almost parallel to that of the light-emitting element and a tilt angle almost equal to that of the light-emitting element and receives scattered light of the light emitted from the light-emitting element. A condensation detection unit detects the state on the mirror surface on the basis of the scattered light received by the light-receiving element. A moisture detection device is also disclosed.