Abstract: A method reduces drift induced by environment changes when imaging radiation from a scene in two wavelength bands. Scene radiation is focused by two wedge-shaped components through a lens onto a detector that includes three separate regions. The wedge-shaped components are positioned at a fixed distance from the lens. The radiation from the scene is imaged separately onto two of the detector regions through an f-number of less than approximately 1.5 to produce a first pixel signal. Imaged radiation on each of the two regions includes radiation in one respective wavelength band. Radiation from a radiation source is projected by at least one of the wedge-shaped components through the lens onto a third detector region to produce a second pixel signal. The first pixel signal is modified based on a predetermined function that defines a relationship between second pixel signal changes and first pixel signal changes induced by environment changes.

Abstract: Devices image radiation from a scene that includes two materials with spectral characteristics in two different wavelength regions. A lens forms an image of the scene on a detector that includes an array of elements. A filtering arrangement integrated with the detector allows half of the detector elements to detect radiation in one of the wavelength regions and the other half of the detector elements to detect radiation in the other wavelength region. Each detector element can be constructed from two different sub-elements that are sensitive to radiation in one of the respective wavelength regions. A blackbody source positioned within the devices reduces drift induced by changes to the environment surrounding the devices. The blackbody source projects radiation onto a region of the detector that does not receive radiation from the scene. Pixel signals produced from the scene radiation are modified based on pixel signals produced from the blackbody.

Abstract: A method reduces drift induced by environment changes when imaging radiation from a scene in two wavelength bands. Scene radiation is focused by two wedge-shaped components through a lens onto a detector that includes three separate regions. The wedge-shaped components are positioned at a fixed distance from the lens. The radiation from the scene is imaged separately onto two of the detector regions through an f-number of less than approximately 1.5 to produce a first pixel signal. Imaged radiation on each of the two regions includes radiation in one respective wavelength band. Radiation from a radiation source is projected by at least one of the wedge-shaped components through the lens onto a third detector region to produce a second pixel signal. The first pixel signal is modified based on a predetermined function that defines a relationship between second pixel signal changes and first pixel signal changes induced by environment changes.

Abstract: Devices image radiation from a scene that includes two materials with spectral characteristics in two different wavelength regions. A lens forms an image of the scene on a detector that includes an array of elements. A filtering arrangement integrated with the detector allows half of the detector elements to detect radiation in one of the wavelength regions and the other half of the detector elements to detect radiation in the other wavelength region. Each detector element can be constructed from two different sub-elements that are sensitive to radiation in one of the respective wavelength regions. A blackbody source positioned within the devices reduces drift induced by changes to the environment surrounding the devices. The blackbody source projects radiation onto a region of the detector that does not receive radiation from the scene. Pixel signals produced from the scene radiation are modified based on pixel signals produced from the blackbody.

Abstract: A method reduces drift induced by environment changes when imaging radiation from a scene in two wavelength bands. Scene radiation is focused by two wedge-shaped components through a lens onto a detector that includes three separate regions. The wedge-shaped components are positioned at a fixed distance from the lens. The radiation from the scene is imaged separately onto two of the detector regions through an f-number of less than approximately 1.5 to produce a first pixel signal. Imaged radiation on each of the two regions includes radiation in one respective wavelength band. Radiation from a radiation source is projected by at least one of the wedge-shaped components through the lens onto a third detector region to produce a second pixel signal. The first pixel signal is modified based on a predetermined function that defines a relationship between second pixel signal changes and first pixel signal changes induced by environment changes.

Abstract: A method reduces drift induced by environment changes when imaging radiation from a scene in two wavelength bands. Scene radiation is focused by two wedge-shaped components through a lens onto a detector that includes three separate regions. The wedge-shaped components are positioned at a fixed distance from the lens. The radiation from the scene is imaged separately onto two of the detector regions through an f-number of less than approximately 1.5 to produce a first pixel signal. Imaged radiation on each of the two regions includes radiation in one respective wavelength band. Radiation from a radiation source is projected by at least one of the wedge-shaped components through the lens onto a third detector region to produce a second pixel signal. The first pixel signal is modified based on a predetermined function that defines a relationship between second pixel signal changes and first pixel signal changes induced by environment changes.

Abstract: An optical inspection apparatus operates at high speed at very high resolution for detecting defects in transparent disks in a production environment. These transparent disks are of the type commonly used as disk platters in hard disk drives. This apparatus uses a laser beam directed to a polygon scanner, which provides a linear scan of the beam along a radius of the disk. The disk to be inspected is rotated such that its entire surface passes the scan path of the laser beam. The laser beam, after passing through the unit to be inspected, is directed to a parallel detector array, which detects changes in the nominal Gaussian distribution of the laser beam that correspond to defects in the surface of the transparent disk above a programmable threshold level. This parallel detection method allows the inspection apparatus to identify defects much smaller than the diffraction limits of the optics used, and will accurately identify changes of the laser beam caused by defects in the disk.

Abstract: An optical inspection apparatus operates at high speed at very high resolution for detecting defects in reflective disks in a production environment. These reflective disks are of the type commonly used as disk platters in hard disk drives. This apparatus uses a laser which provides a light beam directed to a polygon scanner, which provides a linear scan of the beam along a radius on both sides of the disk by using two mirrors to direct the light beam. The disk to be inspected is rotated such that its entire surface passes the scan path of the light beam. The light beam is reflected off the reflective disk, and returns to the scanning optics and the polygon scanner in a path coincident with the transmitted light beam.

Abstract: An optical inspection apparatus operates at high speed at very high resolution for detecting defects in transparent flat panels in a production environment. This apparatus uses a laser which provides a light beam directed to a polygon scanner, which provides a linear scan of the beam along the width of the flat panel. The flat panel to be inspected is moved such that its entire surface passes the scan path of the light beam. The light beam passes through the transparent flat panel, and is reflected off a spherical mirror, back through the transparent flat panel, and returns to the scanning optics and the polygon scanner in a path coincident with the transmitted light beam.

Abstract: An optical inspection apparatus operates at high speed at very high resolution for detecting defects in flat, polished media in a production environment. The configuration of the first embodiment is used to inspect transparent disks such as those used as disk platters in hard disk drives. The configuration of the second embodiment is used to inspect reflective disks. The configuration of the third embodiment is used to inspect transparent flat panels such as those commonly used in Liquid Crystal Display (LCD) panels. All embodiments use a laser providing a light beam directed to a polygon scanner, which provides a linear scan of the beam. The unit to be inspected is moved such that its entire surface passes the scan path of the light beam. The light beam, after contacting the unit to be inspected, is directed to a parallel detector array, which detects changes in the nominal Gaussian distribution of the light beam that correspond to defects above a programmable threshold level.