Astigmatic aberration of grating pair and its use of astigmatic compensation

Astigmatic aberration of a grating pair has been noticed since Matinez (1986) built the first-order theoretical model for treatment of the pulsed beam through the grating pair. However, this aberration is always neglected, since the grating pair used in pulse stretching and compression is usually arranged near the Littrow angle (/spl theta//sub L/). Furthermore, Matinez´s model derived by the first order approximation of the grating diffraction cannot perfectly describe the astigmatic aberration of the grating pair. Recently, we built a new theoretical model without the first-order approximation of the grating diffraction. Our theoretical model allows us to study the characteristic of the grating pair more comprehensively. In this paper, we study the astigmatic aberration of the grating pair both theoretically and experimentally.