Abstract: A digital preservation system (10) for accepting a digital data record as input, for writing the data record in human-readable form onto a preservation-quality medium (210), for storage of the medium (210), and for retrieval of the data record from the medium (210). The system (10) is modular, allowing scaling of the system (10), allowing preferential selection of specific image handling components, and allowing replacement of complete subsystems while minimizing the likelihood of data loss. The digital preservation system (10) preserves a data record in human-readable form, along with an associated metadata record, allowing the human-readable preserved data record to be readable in the distant future, independent of specific reading hardware.

Abstract: An improvement for non-uniformity correction in a printing apparatus (10) wherein an image forming assembly (22) forms an image using a plurality of exposure elements, and the amount of exposure energy at each individual exposure element is capable of being varied. A test print (50) is generated, having a series of test patches or zones with predetermined density levels. A scanner (40) scans the test print (50) to obtain density value readings within each test density zone (52) for each pixel that corresponds to each exposure element. Density value readings are averaged. Then, difference in measurement from this average is used to compute a correction factor for each individual exposure element. An image data manager (12) conditions the input data by this correction factor, then sends the conditioned image data to the image forming assembly (22) for printing.

Abstract: A method and apparatus for monochromatic printing which records an image from digital image data onto a photosensitive medium (160) is disclosed. The apparatus includes the following: A light source (29) provides the monochromatic illumination. A uniformizer uniformizes a wavefront of light emitted from the light source (29). A polarizer (134) for filtering the uniformized light provides a polarized beam having a predetermined polarization state. A spatial light modulator (52) has a plurality of individual elements capable of altering the polarization state of the polarized beam to provide an exposure beam for printing. A state of each of the elements is controlled according to the digital image data. An optics assembly (11) is used for directing the polarized beam to the modulator and the exposure beam from the spatial light modulator (52). A lens assembly (132) is used for directing the exposure beam onto the photosensitive medium (160).

Abstract: An improvement for non-uniformity correction in a printing apparatus (10) wherein an image forming assembly (22) forms an image using a plurality of exposure elements, and the amount of exposure energy at each individual exposure element is capable of being varied. A test print (50) is generated, having a series of test patches or zones with predetermined density levels. A scanner (40) scans the test print (50) to obtain density value readings within each test density zone (52) for each pixel that corresponds to each exposure element. Density value readings are averaged. Then, difference in measurement from this average is used to compute a correction factor for each individual exposure element. An image data manager (12) conditions the input data by this correction factor, then sends the conditioned image data to the image forming assembly (22) for printing.

Abstract: A printhead having a plurality of exposure elements (18) with improved non-uniformity correction. Spatial variance of the energy emitted by the exposure elements (18) is measured and used to establish spot size characteristics for each exposure element. A sensor (26) scans multiple points along the pixel area written by each exposure element (18)and measures a corresponding output power value at each point. The output power values are evaluated to determine a maximum output power value for the exposure element (18) and to obtain a spot size for the exposure element (18) based on full-width at half-power values. Both spot size data, which can thus be obtained and stored only once, and output power values are then used to correct for non-uniformity's between the exposure elements (18).

Abstract: A monochrome printer (100) and a method for printer optics design utilizing a spatial light modulator (52), able to deploy a number of possible monochromatic light sources for use with a number of different types of photosensitive media (160), are disclosed. The printer provides high resolution and grayscale imaging capability for monochromatic applications such as micrographics and for diagnostic imaging. In the apparatus and method, illumination optics (11) receive a source light beam, from one or more LEDs or from a number of other possible monochromatic light sources available on the printer (100), uniformize and polarize the beam, and direct the beam through a polarization beamsplitter element (50). The polarization beamsplitter element (50) directs one polarization state of light to an LCD spatial light modulator (52).