| 摘要 |
An apparatus and method for a large-format scanner. In a preferred embodiment, a device for scanning an image on a medium having a width and providing signals representing the image includes a frame, a transport, a lamp and a plurality of sensors. The transport is mounted to the frame and is used for moving the medium along a first axis transverse to the medium's width. The lamp illuminates the medium. The lamp has a first end and a second end wherein the first end and the second end are folded back approximately 180 degrees, so that the lamp produces uniform brightness across the width of the medium. The plurality of sensors are proximate to the transport, span the medium's width, and the sensors provide a signal representative of a portion of the image within the illuminated portion of the medium. The device may also include a focal length adjustor, mounted to the frame between the sensors and the transport, for adjusting the distance between the medium and the sensors. In another embodiment, a method for focusing a device for scanning an image on a medium having a plurality of sensors each sensor having a length is presented. A scan pattern is placed into the device for scanning which creates an output of the scan pattern. The scan pattern has black dots and white spaces, where the black dots are approximately the length of a sensor, and the white spaces are positioned between the black dots. The white dots are of such a size that the black dots are spaced apart at a distance which is greater than the length of a sensor. The output of the scan pattern is displayed and the focal length between the sensor and the medium is changed based on the output of the scan pattern so that at least one sensor produces a signal which is displayed as a peak black reading.
|
