ANTIBOW DEVICE FOR LASERS

摘要

A device for use in a hologon deflection system rotating at an angle OmegaR (15) to produce a scan line from a laser beam having wavelength Lambda. The device comprises a prism (21) having a grating (23) on at least one surface. The prism is positioned to deflect the scan line after hologon deflection of the laser beam (19). The prism has an apex angle between scan line intersecting surfaces of Omega alpha . The grating has a grating spacing D. Deflection of the scan line due to the angle Omega alpha is designed so that it is equal to the deflection of the scan line due to the grating. This produces a scan line having bow of less than 1/600 of the bow of the scan line without the prism and effectively eliminates wobble. The range for the apex angle Omega alpha may be from about 1 DEG to about 30 DEG , and preferably from about 2 DEG to about 6 DEG . The grating spacing ranges from about 0.0001 to about 0.001 millimeters.