34 and 36 are attached to shafts 20 and 28 respectively the motion of the rotation coupling arm 36 is coupled to that of rotation coupling arm 34 by cables 38 and 40 which translate the rotational motion of shaft 20 to shaft 28 by means of six pulleys 42 44 46 48 50 and 52 the preferred mirror angles as shown in fig2 in this example labeled 34 case 1 34 the angle 16 which is associated with the first mirror 12 is equal to 22 5 degrees this is the angle between the direction of the incident light 18 and a line normal to the first mirror 12 the other angle 30 which is associated with the second mirror 26 is equal to 67 5 degrees this angle is defined as the angle between the axis about which the second mirror 26 rotates and the line normal to the second mirror 26 two other examples of mirror angles are shown for comparison in fig3 and in fig4 these examples are labeled 34 case 2 34 and 34 case 3 34 respectively the results of an optical analysis conducted on the present invention is shown in fig5 8 the analysis assumes that the first mirror 12 rotates at the same rate as the second mirror 26 as will be appreciated a system could easily be employed in which.