Abstract: An on-vehicle fiber-optic cylinder pressure sensor capable of detecting the pressure within a combustion chamber with precision has an optical fiber capable of converting a change in the pressure within a combustion chamber received on its outer surface on an engine gasket into a change in the light quantity passing therethrough. A light emitting device for emitting the passed-through light; a photosenses or senses the passed-through light of which the light quantity has been changed. A converter converts the light quantity of the passed-through light into an electric signal. A reference pressure setting apparatus sets a reference electric signal. A signal processor includes an apparatus for watching a corresponding reference electric signal to the reference electric signal included in the detected electric signal.

Abstract: A combustion pressure sensor suitable for a highly precise combustion control system of an automobile engine and a sensing system using the sensor. The combustion pressure sensor includes a SOI substrate having a three-layered structure of a first silicon plate, a thermal oxide film, and a second silicon plate, wherein a combustion pressure is sensed on the basis of a pressure or a force applied to the first silicon plate.

Abstract: An in-cylinder pressure sensing apparatus for a multi-cylinder engine has a plurality of sensing parts packaged between a cylinder head and a cylinder block of an engine having a plurality of cylinders and being operative to detect a signal indicative of an internal pressure of each of the plurality of cylinders. A detection circuit is provided for connecting the sensing parts in series and for overlapping detection signals obtained from the individual sensing parts to take out a resulting overlapped signal. A reference signal generator operates to supply a reference signal for separating detection signals corresponding to the individual cylinders from the overlapped signal. A unit is also provided for separating the detection signals, detected in accordance with pressures of the individual cylinders, from the overlapped signal on the basis of the reference signal.

Abstract: An optical fiber pressure sensor for measuring a pressure on the basis of an optical power loss depending on a configuration change of an optical fiber comprising a luminescence device optically connected with at least an optical fiber which is constructed with a main part for propagating a light protective coating member for protecting the main part. A light intercepting device detects a light passing through the optical reflected light from the optical fiber. A bending device bends at least a part of the optical fiber according to a measured pressure. The optical fiber pressure sensor is characterized by being used when a normalization frequency V value of the optical fiber is smaller than 90% of a normalization cut-off frequency defining a single transmission mode condition of the optical fiber.

Abstract: The distance to a target object is measured by capturing the image in front of the driving vehicle using an image sensor, identifying a target object such as a vehicle ahead to which the distance is to be measured, and projecting a laser beam onto the target object. The distance to the target object is measured by angular surveying, using an image sensor for capturing an image as a laser light detection unit.

Abstract: A physical quantity detecting apparatus comprises at least one optical fiber, at least one light emitting means for emitting an incident light beam on the optical fiber, at least one light receiving means for detecting an outgoing light beam from the optical fiber, physical quantity applied position information generating means for providing information indicative of a position of a portion at which a physical quantity is applied to the optical fiber, and operation means for receiving signals from the light receiving means and physical quantities applied position information generating means and calculating a change with time in physical quantity at respective positions on the optical fiber.