Abstract: The present invention provides a sensor that exhibits a small effect on a detection target during detection, a high detection sensitivity, a wide dynamic range for detection, and a small change after repeated detection, as well as a composition suitable for use in the sensor. The composition is a polyrotaxane composition containing two polyrotaxane cyclic molecules crosslinked with a crosslinking agent present between the molecules, wherein the polyrotaxane composition exhibits a hysteresis loss of 10% or less, an elongation at break of 200% or more, an initial Young's modulus of 5 MPa or less, and a relative dielectric constant of 8.0 or more. The sensor includes a film formed of the aforementioned polyrotaxane composition, and elastomer-made electrode layers disposed on both surfaces of the film.

Abstract: A transducer device includes a first dielectric layer, a first electrode layer and a second electrode layer that hold the first dielectric layer in a thickness direction, a second dielectric layer provided continuously from the first dielectric layer, a third electrode layer and a fourth electrode layer that hold the second dielectric layer in the thickness direction, and a controller. The controller calculates a command value of voltage to be applied to the first electrode layer and the second electrode layer and applies a voltage corresponding to the command value to the first electrode layer and the second electrode layer so that the first dielectric layer is deformed in the thickness direction. The controller measures a capacitance Cs of the second dielectric layer via the third electrode layer and the fourth electrode layer and calculates the command value in reference to the measured capacitance Cs.

Abstract: The light-emitting device has a semiconductor layer including a p-layer, a light-emitting layer, and an n-layer, which are formed of a Group III nitride semiconductor, and an n-electrode on the n-layer. The device also has a device isolation trench which runs along the outer periphery of the semiconductor layer and which provides the semiconductor layer with a mesa shape; and an insulation film continuously provided on first to third regions, the first region being an outer peripheral region of the n-layer, the second region being the side surface of the trench, and the third region being the bottom surface of the device isolation trench. The n-electrode consists of two pad portions and a wire trace portion. The outer peripheral wire trace portion is formed as a frame completely contouring the periphery of the device.