BLAZED HOLOGRAPHIC GRATING EFFICIENCY-NUMERICAL COMPARISON WITH DIFFERENT PROFILES

Numerical study of a blazed holographic grating efficiency is made for blazing in low (first) and high (fourth) orders. Comparison with a ru led grating with similar blaze angle is done in order to explain the s hift in the observed blazing position for the holographic grating. Con secutively approximating the curved holographic grating profile by inc reasing the number of segments of the ruled grating, it appears that t he largest difference between the holographic grating and the grating with an ideal triangular profile is mainly due to the flatness of the groove top. The deviation from the ideal profile affects much stronger the blazing in higher orders.