Abstract: A method of controlling an amount of exposure, in which, when a pattern on a reticle is illuminated by illuminating light from a light source so as to be projected onto a substrate, an amount of light at a position substantially conjugate with a projected area on the substrate is measured and an amount of exposure applied to the substrate is controlled based upon a result of this measurement. The position at which the amount of light is measured is a position substantially conjugate with an off-optical-axis position in the projected area on the substrate.

Abstract: When a pattern on a reticle (8) is illuminated by illuminating light from a light source (1) so as to be projected onto a substrate (11) to expose the same, the illuminating light is diverted by a half-mirror (13), the amount of exposure is measured on the optical path of the diverted illuminating light and the amount of exposure of the substrate is controlled based upon the result of such measurement. The position of the half-mirror (13) is set in such a manner that the optical path of the diverted illuminating light passes through part of an optical element (5) situated on a side of the half-mirror (13) that faces the light source (1), and the amount of exposure is measured on the optical path of the diverted illuminating light following its passage through the optical element. This makes it possible to reduce the space for exposure measurement that is necessary to control the amount of exposure.

Abstract: Disclosed is an illumination optical system for illuminating a surface, to be illuminated, with use of light from a light source, which includes a diffractive optical element for forming a desired light intensity distribution upon a predetermined plane, and an angular distribution transforming unit for transforming an angular distribution of light incident or to be incident on the diffractive optical element into a desired distribution.

Abstract: Disclosed is an exposure amount control method wherein an original is illuminated with exposure light, emitted from an exposure light source, through one or more light intensity uniforming optical systems, so that a pattern of the original is illuminated is projected onto and printed on a substrate, wherein a first illuminance sensor is used to measure an illuminance of exposure light a branched at a light source side of the or one of the light intensity uniforming optical system which is closest to the original, wherein an exposure amount of the substrate is controlled on the basis of a measurement output of the first illuminance sensor, wherein a second illuminance sensor is used to measure an illuminance at a position substantially conjugate with the substrate, and wherein an output of the first illuminance sensor is calibrated on the basis of a measurement output of the second illuminance sensor.

Abstract: Paints of different color brightness not deposited on the work to be coated in a powder coating process are recovered as a mixture, and a fresh paint of high or low color brightness is added to the mixture to adjust its color brightness and thereby prepare a fresh mixture of medium color brightness which can be used as a paint of medium color brightness.

Abstract: A workpiece surface is measured to detect a defective portion with a projection and a depression on the workpiece surface by using an optical inspecting apparatus having a projector for radiating a detecting light towards the workpiece surface and a picturing device for receiving a reflected light from the workpiece surface. A reflected light from the workpiece surface is pictured in a condition in which a focal surface of the picturing device is positioned away from the workpiece surface to the side of the picturing device relative to an entire region of that effective inspecting range of the workpiece surface from which the picturing device can receive the reflected light. The defective portion on the workpiece surface is detected from a dark portion which appears on the image of the picturing device.

Abstract: A method of inspecting a curved surface of a workpiece by a surface inspecting apparatus provided with a projecting device for illuminating the workpiece surface to be inspected with detection light, a detecting device for receiving and detecting the light reflected from the workpiece surface, and a condensing optical system for causing the reflected light to converge on a light-receiving surface of the detecting device. According to the method, the surface inspecting apparatus is successively displaced along the workpiece surface and the reflected light is detected by the detecting device. Further, image data obtained from the detecting device is held and binary digitized. It is determined whether or not the workpiece surface to be inspected is planar. If it is not planar, then the digitized image data is processed for dilation and erosion. Thus, when the workpiece surface is curved, faulty or defective spots can be reliably detected.