Abstract: A system (50) and method for converting an incoming image of a scene (12) into electronic form adapted for use with focal plane arrays of detectors (24, 28). The inventive system (50) includes a surface (30) having an electromagnetic energy transmissive region (34), a reflective region (32), and a transition region (36) that has varying reflectance. A first focal plane array (24) detects a first portion (18, 39, 43) of the incoming image (12) that is transmitted through the transmissive region and the transition region (36). A second focal plane array (28) detects a second portion of the incoming image (20, 41, 45) reflected by the reflective region (32) and the transition region (36). An image combining system (40) combines the first (43) and second portions (45) of the incoming image via an image combining algorithm and provides a combined image without a dead pixel region. In the illustrative embodiment, the incoming image (12) is focused onto the surface (30) via a first lens (22).

Abstract: Optical metrology method and apparatus for simultaneously measuring changes in figure of a primary mirror and spacing between the primary mirror (58) and a secondary mirror (54). One or more optical heads (62A, 62B, 62C) are attached to structure (66) supporting the secondary mirror (54) and adjacent thereto. Each optical head (62A, 62B, 62C) provides a laser generated output beam. By interferometry and electronics, output signals are generated which indicate the changes in figure of the primary mirror (58) and the spacing between the primary mirror (58) and the secondary mirror (54).

Abstract: Optical metrology apparatus includes one or more first sample point interferometers (SPIs) (16) having a wide dynamic range for measuring a rigid body position of a surface of a structure, such as a segmented mirror (11). At least one second SPI (18), having a lower dynamic range, is employed for measuring a figure of the segmented mirror. Either the first or the second SPIs may also be employed to measure a lateral displacement between the mirror segments (11a, 11b). The use of multiple SPIs, having differing dynamic ranges, within a closed-loop mirror control system is also described.

Abstract: A beam-slicer (6) for generating a plurality of radiation beams, or pencil beams (7), from incident radiation (3). Each of the beams is directed to a different region of space. The beam-slicer includes a substrate (17) that, for a transmission grating embodiment, is comprised of a material that is substantially transparent to incident radiation having wavelengths of interest. The substrate includes a plurality of regions, or sub-apertures (8), formed within a surface thereof, each of the regions defining a blazed transmission or reflection grating for deviating incident radiation into a radiation beam. The blazed diffraction grating is formed such that the wavelengths of interest within each radiation beam are simultaneously deviated at a same, predetermined angle. Also disclosed is a Sample Point Interferometer that includes the beam-slicer. The beam-slicer generates pencil beams, each of which is directed to a retroreflector (9) positioned upon a surface of a structure (10) under measurement.

Abstract: In a multi-color printing process, measurements of the optical density of two different three-color halftone control areas are used to calculate dot gain and solid density of the cyan, magenta and yellow images. Since no single-color solid control targets are used, control targets may be hidden or camouflaged in a border or logo in the final printed product. The two control targets can consist of light and dark near-neutral gray balance targets. Alternatively, two different three-color halftone regions of the printed image can be used as control areas, eliminating the need for separate control targets. Densitometers having blue, green and red filters use the two three-color halftone control areas to provide density measurements which are used by a computer to calculate the densities of cyan, magenta, and yellow halftone images. The computer then calculates the dot gain and solid density of the process inks, which are displayed to a pressman who can make appropriate adjustments to the printing process.

Abstract: In a lithographic printing system, a light source and a plurality of photodetectors are used to monitor the amount of fountain solution interacting with the ink. The light source irradiates an ink form roller and the photodetectors are disposed at a specular angle and at one or more non-specular angles to monitor the reflected light. An electronic circuit is responsive to the output of the photodetectors and is used for providing an indication of the amount of fountain solution emulsified in the ink, and lying on the surface of the ink.

Abstract: In the manufacture of a multilayer polymer film, the thickness and degree of orientation are simultaneously measured. A beam of infrared radiation having predetermined wavelengths is either transmitted through or reflected by the polymer film to be measured and received by a photodetector. The photodetector provides an electrical output signal which can be analyzed to determine the thickness and degree of orientation.

Abstract: A method and apparatus for automatically sensing and maintaining registration of each of the color cylinders utilized in a multi-color printing press is disclosed.Predetermined register marks are printed in the non-image areas on the sheet to be printed. Typically, in a four-color printing process, the black image is used as a reference, and registration of the other three image colors is achieved relative to the black image. Accordingly, a register mark for each process color is printed in the same location as a corresponding black reference register mark.The reference register marks are configured such that the average reflectance of the printed overlay will change as the registration of the color image changes with respect to the black image. In general, the configuration of the register marks for the black and color images differs.The reflectance of each printed overlay is measured on the printing press, while the sheet is moving.

Abstract: An electro-optical device which measures the transmittance of a sample at any desired visible wavelength and simultaneously displays the visual transmittance spectrum of the sample.

Abstract: A reflection spectrophotometer which illuminates a sample with flux derived from a light source, such as a pulsed xenon flashtube, divides the light diffusely reflected by the sample into its component wavelengths and simultaneously senses the energy present at each of the component wavelengths.

Abstract: A reflectometer optical system having an optical axis for illuminating a sample with flux derived from an extended source such as a pulsed xenon flashtube. A wedge-shaped diffuser, symmetric with respect to the optical axis, is used to diffuse the flux emanating from the source and refract it radially outward from the optical axis. The polished inner surface of a cylinder is used to reflect these radially expanding rays such that they converge upon the sample area from all azimuth angles. A series of baffles are located between the diffuser and the sample to limit the flux incident upon the sample to a small angular spread about 45.degree.. A lens located along the optical axis focuses the flux diffusely reflected from the sample onto one end of a fiber optical bundle. An aperture stop disposed between the lens and the sample limits the reflected flux to a small angular spread about 0.degree.