Abstract: A beam of light from a light source is irradiated toward a surface of a transparent plate at an angle of incidence ranging from 86 to 89 degrees or at an angle of incidence ranging from 60 to 89 degrees after being polarized as a P-polarized light beam or S-polarized light beam by a polarizing element disposed between the light source and the transparent plate. This enables a reflected image from a front surface of the transparent plate to be projected on a screen without being influenced by reflection from a rear surface of the transparent plate. By visually inspecting the reflected image on the screen, or by picking up the reflected image by a camera and visually inspecting a picture on a monitor display, or by picking up the reflected image by a camera to obtain density signals representative of the reflected image and calculating the irregularities of the surface of the transparent plate on the basis of the density signals by an image processor.

Abstract: In an inspection method for a transparent object, a transparent object is irradiated with light from a light source, and the surface or interior of the transparent object is inspected by observing transmitted light on the side of the transparent object that is opposite to the light source. An inspection apparatus for a transparent object includes a transparent-object-moving unit, an irradiation unit, and a detection unit. The transparent-object-moving unit moves a transparent object to an inspection position and fixes the transparent object in the inspection position. The irradiation unit emits light from a light source disposed on one side of the transparent object so as to irradiate light onto the transparent object fixed in the inspection position by the transparent-object-moving unit. The detection unit is located on the side of the transparent object opposite the light source and has a detector for detecting light that has been emitted from the light source and has passed through the transparent object.

Abstract: This invention relates to a loose draw detector for a paper machine wet press. Such structure of this type, generally, use laser triangulation displacement sensors mounted and positioned to measure the point of web release from the center roll and measure paper web wrinkles in the form of rapid fluctuations/decreases in the standoff distance between sensors and the web passing over the leadout roll to determine loose draw.

Abstract: The apparatus for inspecting a substrate of the present invention comprises substrate holding member for holding a substrate to be inspected, a driving mechanism for raising the substrate holding member to a predetermined angle or less, a position coordinate detecting section provided at side edge of the substrate in at least two directions, for detecting coordinates of a defect present in the substrate, an observation system supporting section provided for supporting a micro observation system and moving on the surface of the substrate, and a controlling section for controlling of the movement of the micro observation system of the observation system supporting section to correspond to a defect present in the substrate, on the basis of the position coordinates of the defect detected by the position coordinate detecting section.

Abstract: This light scattering technique for size measurement is based on the fact that an illuminated particle (inclusion) serves as a secondary radiation source in a manner which is related to its size. This technique allows for detection of inclusions in the interior of transparent solid media, such as bulk glass. When illuminated with a beam of monochromatic light such as a laser beam as the primary light source, the angular distribution of the scattered intensity originated from the inclusion in the micron to submicron range, is a function of intensity, wavelength and index of refraction. A lens and light trap block the primary light for reaching a detector. The light trap, however, allows the secondary scattered light to reach the detector.

Abstract: A beam of light from a light source is irradiated toward a surface of a transparent plate at an angle of incidence ranging from 86 to 89 degrees or at an angle of incidence ranging from 60 to 89 degrees after being polarized as a P-polarized light beam or S-polarized light beam by a polarizing element disposed between the light source and the transparent plate. This enables a reflected image from a front surface of the transparent plate to be projected on a screen without being influenced by reflection from a rear surface of the transparent plate. By visually inspecting the reflected image on the screen, or by picking up the reflected image by a camera and visually inspecting a picture on a monitor display, or by picking up the reflected image by a camera to obtain density signals representative of the reflected image and calculating the irregularities of the surface of the transparent plate on the basis of the density signals by an image processor.

Abstract: This light scattering technique for size measurement is based on the fact that an illuminated particle (inclusion) serves as a secondary radiation source in a manner which is related to its size. This technique allows for detection of inclusions in the interior of transparent solid media, such as bulk glass. When illuminated with a beam of monochromatic light such as a laser beam as the primary light source, the angular distribution of the scattered intensity originated from the inclusion in the micron to submicron range, is a function of intensity, wavelength and index of refraction. A lens and light trap block the primary light for reaching a detector. The light trap, however, allows the secondary scattered light to reach the detector.

Abstract: The invention relates to a method of determining the optical quality of and for detecting faults in flat glass, especially float glass, or other optically transparent materials, a video camera (1) being arranged to monitor an illuminating device (3) either through a glass (2) or by observing the reflection thereof on the glass or material, the focus being on the glass (2) and the material, respectively, and the video camera (1) generating signals in dependence on the quality of the glass (2), with these signals being evaluated, wherein an illuminating device (3) is used whose color and/or intensity is changed in a defined manner, the observation spot (6) of the video camera (1) in the faultless condition of the glass (2) is located substantially in the middle of the illuminating device (3), the illuminating device (3) has assigned thereto two video signals U1,U2, and a change of intensity of the video signals U1,U2 is used for evaluating the quality of the glass (2).

Abstract: Apparatus and method for measuring an aerial image whereby influences of various defects existing on patterns formed on a photomask as well as the surface of the photomask substrate can be inspected. The aerial image measuring apparatus includes an optical transmitting device, an optical reflecting device and an aerial image forming device. The optical reflecting device includes a beam splitter and a reflecting mirror. The reflecting mirror switches the path of light so that the light transmitted along the reflected light path is irradiated to the surface of the photomask on which the patterns are formed. According to an aerial image measuring method of the present invention, either transmitted light or reflected light is selected for analysis, the selected light is converted into an electrical signal to form an aerial image, and the aerial image is measured.