Large-aperture optical system

The invention relates to a large-aperture optical system. The large-aperture optical system comprises a front lens group and a rear lens group which are sequentially arranged from an object side to animage side, wherein the front lens group comprises a first lens (1) with negative focal power, a second lens (2) with negative focal power and a third lens (3) with positive focal power; the rear lens group comprises a fourth lens (4) with positive focal power, a fifth lens (5) with negative focal power, a sixth lens (6) with positive focal power, a seventh lens (7) with negative focal power andan eighth lens (8) with positive focal power; and the fifth lens (5) and the sixth lens (6) are glued to form a doublet lens with positive focal power. According to the large-aperture optical system,the positive focal power and the negative focal power of each lens are optimally configured, so that the aberration is effectively corrected, and the imaging quality of the whole optical system is further improved. 本发明涉及一种大光圈光学