Compensation methods for alignment errors of tiled grating-pair compressor

Base on the model of gratingpair compressor, the formula of angular dispersion caused by alignment errors was derived. The compensative relations between the tilt angular errors and groovewidth difference were obtained and the compensative methods were discussed. The results show that the relative rotation about the position normal to groove can compensate the error caused by the relative rotation about the position normal to the plan of gratings, the relative rotation about the position parallel to groove can compensate the error caused by groovewidth difference and the relative rotation about the position normal to groove or about the position normal to the plan of gratings can compensate the error caused by groove-width difference. The compensation effects of the first two metho