Low-power flat-field apochromatic microscope objective

A low-magnification flat-field apochromatic microobjective includes a first lens group having a positive refractive power, a second lens group having a negative refractive power, and a third lens group having a positive refractive power arranged in order from an object side, and satisfies the following conditions: f1/flt; 1.5 parts; f2/flt; 1.0); f3/flt; 1.5 parts; 1.0 lt; f3/f1 + f2; wherein f is the focal distance of the low-power flat-field apochromatic microscope objective, f1 is the focal distance of the first lens group 10, f2 is the focal distance of the second lens group, and f3 is the focal distance of the third lens group. According to the invention, the focal distances of the first lens group, the second lens group and the third lens group are limited, so that the optical system can realize a longer working distance and a larger numerical aperture under the condition of low magnification, and meanwhile, spherical aberration, field curvature and distortion are preliminarily corrected. 一种低倍平场复消色差显微物镜