Optical scanning apparatus

DETAILED DESCRIPTION It is therefore an object of the present invention to provide a relatively inexpensive optical scanning apparatus which can substitute for the conventional optical scanning apparatus.
It is a more specific object of the present invention to provide a optical scanning apparatus which does not use the expensive acoustooptic device of the prior art.
Briefly, in the present invention, a hologram array is utilized which includes a plurality of adjacent holograms which are illuminated at an acute angle by laser diodes.
Each laser diode output is modulated by an information source such as a computer output or the like.
The outputs of the hologram array leave the hologram at acute angle such that the focal points of the beams leaving the hologram array are focused on the object surface (a photo receptor or the like).
Closely controlled spacing of the outputs of the holograms is achieved by appropriate spacing of the holograms.
In order to provide two dimensional scanning, an appropriate combination of spherical and cylindrical lenses may be utilized together with a moving polygonal mirror to move the output beams from the hologram across the surface of the photoreceptor.
A fairly extensive theoretical description of the use of holograms in optical scanning apparatus can be found in the U.
S.
Pat.
No.
4,348,080 issued in Sept.
7, 1982 and assigned to a common assignee of this invention.
This patent is incorporated herein by reference, as is an article on holographic linear gratings found in the Journal of the Optical Society of America, volume 73, No.
9 pages 11131118.
Further objectives and advantages of the present invention will become apparent to a person of skill in the art who reviews the subject invention disclosure in conjunction with the following figures: