Large-view-field projection exposure objective lens system applied to projection photoetching machine

The invention relates to a large-view-field projection exposure objective lens system applied to a projection photoetching machine. The large-view-field projection exposure objective lens system is used for transferring a pattern on a mask plate of the projection photoetching machine to a silicon wafer after imaging copying. The large-view-field projection exposure objective lens system is composed of 20 lenses, the resolution of the objective lens system is 700 nm, the amplification factor is -0.25 times, and the exposure view field is 44 mm * 44 mm. The conjugate distance L (from the object space to the image space) of the projection exposure objective lens system is 740mm, and the system is compact in structure; and meanwhile, a glass material with relatively high transmittance to an i line (365nm) is selected, the optical transmittance of the system is improved, and the field curvature, distortion and wave aberration of the system are corrected by adopting a spherical surface, so that the requirements of