Abstract: This invention relates to an automatic focusing apparatus, in that a position of a substrate mounted on the base of the apparatus is detected as a pressure value by a first detecting means, such as an air micrometer, in that second detecting means, such as an air micrometer, are provided on a portion of the apparatus to determine a reference pressure, gas supplied into the second detecting means is derived from the same supply source as that of the first detecting means, and further, in that the base can be controlled and moved until the difference between the reference pressure and the detected pressure reaches a predetermined constant value, whereby the surface of the sample can be automatically positioned at a desired focusing position.

Abstract: A suction air muffler having a muffler case connected to the air cleaner, wherein a suction pipe connected at one end to the air inlet port formed in the muffler case extends through the muffler case. Air drawn by suction into the suction pipe passes through the muffler case before being delivered to the air cleaner, so that the noise produced by the air drawn by suction into the suction pipe of a motorcycle can be minimized.

Abstract: An improved optical exposure apparatus for use in exposing a workpiece to a desired light pattern with a high alignment accuracy and a high operational speed is disclosed. The apparatus comprises a moving table on which a workpiece to be exposed is disposed, a movable holder on which a mask having an original pattern is disposed, a light source for irradiating said mask, a reduction lens for projecting a reduced pattern of said original pattern onto said workpiece, means for positioning said moving table to a predetermined position, means for detecting the error of said table positioning, means for calculating a value of the error of positioning the workpiece divided by the reduction rate of the reduction lens, and means for automatically shifting said movable holder by the calculated value so as to cancel said error.

Abstract: Description is made of improvements in a photoelectric microscope which is employed for the measurement of a very small distance. According to this invention, an optical system for making point-symmetric images is disposed in an optical path of an objective of a photoelectric microscope so as to form on an identical focal plane a pair of (two) images of a reference line (or mark) on a test piece which are in the relation of point symmetry to each other, and the distance between the pair of (two) images is measured, whereby the deviating distance of the reference line (or mark) on the test piece from the optic axis of the objective is evaluated. The distance between the pair of images is evaluated by gauging the time difference between two detection signals which are obtained by scanning the pair of images at equal speeds with photoelectric detectors.

Abstract: A combustion means in which, when the combustion is effected, a flame is stably formed at a small distance from a fuel discharge nozzle is disclosed, which combustion means comprises an outer cylinder, an inner cylinder and an air feed cylinder and is characterized by the fact that a fuel discharge nozzle is disposed at the bottom of said outer cylinder, a path for gas circulation is constituted by the space intervening between said inner cylinder and outer cylinder, and air discharge opening from said air feed cylinder and a combustion gas suction inlet serving to establish communication between said inner cylinder and gas circulation path are disposed at one end of said gas circulation path, and a reflux opening serving to admit the gas from said gas circulation path into the inner cylinder is disposed at the other end of the gas circulation path.