Samples per inch

Abstract: A method and disc drive in which tracks and data rates are designated is provided. Under the invention, the write width of a transducer head is determined. A tracks per inch value is adjusted based on the write width, and a data transfer rate is adjusted based on the adjusted tracks per inch value. In particular, the data transfer rate is adjusted such that the adjusted tracks per inch value and the adjusted data transfer rate provide a capacity for the head that is equal to a nominal capacity.

Abstract: In a printer having P+X printing elements for printing pixels with a vertical center-to-center spacing R1 during a plurality of line scans, and a stepper motor for moving a record medium in increments R2 where R2 is greater than R1, all points addressable printing is obtained by a combination of movement of the record medium orthogonal to the line scan direction and shifting address signals applied to the print elements. The stepper motor moves the record medium a distance k2R2 between successive line scans and address signals are applied to (n+ki)th... (n+k1+P-1)th print elements to cause a shift k1R1, such that the sum of the distance the record medium is moved before a line scan and the shift caused by the address signals during a scan is equal to PR1 where P is the number of print elements active during the preceding line scan, or equal to any desired integral multiple of R1 in other print modes. With a print head capable of printing pixels on 1/300 inch centers, and a stepper motor capable of moving the record medium in minimum increments of 1/150 inch, all points addressable printing with a pixel resolution of 1/300 inch is achieved with increased accuracy. This same arrangement also permits printing in the character mode with a line-to-line spacing of exactly 1/6 inch. In a second embodiment the line-to-line spacing differs from 1/8 inch by a distance that has minimal impact on print quality.

Abstract: The digital radiology department demands an accurate means to both digitize x-ray film and to represent digital data on film. This paper gives preliminary test results of the performance of a prototype laser scanner and printer system manufactured by the Konishiroku Photo Ind. Co., Ltd., for use in radiological imaging. The laser scanner digitizes x-ray film at a resolution of 2000x2400x10 bits for a 14x17 inch film. A variety of film sizes and optical density ranges can be scanned. The laser printer writes a digital image onto either 8x10 or 14x17 inch film with a pixel size of 80x80 microns. A 14x17 inch film can be written at up to 4288x5275x8 bit pixel resolution. A maximum of 16 images can be placed onto a single film. Software controlled look-up tables are used to correct for nonlinearities in the production of film density from digital data. Image magnification and minification are available under software control. Tests of uniformity, linearity, contrast and spatial resolution, signal to noise ratio, and laser field intensity distribution experiments for the laser scanner and printer have been conducted. This paper presents the results of these tests and some early clinical results.

Abstract: A raster output scanner which can be instantly varied between the most common spot densities, such as 240, 300, 400 and 600 spots per inch in the slow scan direction. The scanner produces a plurality of scans per inch, either by scanning with one beam or several simultaneous beams, the number of scans per inch being a common denominator of all of the spot densities. For example, for the above spot densities, 1200 scans per inch would be required. Then each scan is independently modulated so that the correct number of spots per inch are generated. Thus, for example, if 4 consecutive scans are used to create one spot, then the spot density will be 300 spots per inch.