Straight-Line, Two-Dimensional Holographic Scanner
Original Publication Date: 1987-Jan-01
Included in the Prior Art Database: 2005-Jan-31
Straight-line, two-dimensional scanning is achieved, as shown in Fig. 1, by using two holographic scanners, mounted on the same shaft and rotating together. (Alternately, the holograms are on opposite sides of the same substrate.) The lower hologram, Hl, is recorded with the proper reference beam angle (a=45.55 degrees) and an object beam angle, bi, that varies from facet to facet. The reconstructed beams resulting from illumination of each facet impinge on the upper hologram, Hu, at different radial locations. Each facet of the upper hologram is recorded with a reference beam corresponding to these different direc tions of illumination, but all with the same object beam direction, b=44.45 degrees.