telescope is used between the aom and the grating c the grating based phase control optical delay line using an acousto optic modulator and a diffraction grating to scan an input beam shown in fig3 of the 39 645 patent d the grating based phase control optical delay line using a scanning mirror to change the grating input angle shown fig4 of the 39 645 patent as described in the 39 645 patent a telescope is disposed between the scanning mirror and the grating to prevent beam walk off at the grating e the grating based phase control optical delay line using a steerable grating shown in fig5 of the 39 645 patent f the grating based phase control optical delay line using a radially scanned circular holographic optical element shown in fig6 of the 39 645 patent g the mirror configuration for pulse shaping shown in fig1 of the 39 645 patent h the grating based phase control optical delay line in a double pass configuration shown in fig1 of the 39 645 patent i the grating based phase control optical delay line with elements that can be modified to change the scanning group delay shown in fig1 of the 39 645 patent j the grating based phase control optical delay line using a scanning grating shown in fig1 of the 39 645 patent k the scanning optical delay line apparatus using a rotating circular holographic optical element to produce a scanning group delay shown in fig1 of the 39 645 patent l the scanning optical delay line apparatus using an acousto.