The invention discloses an object space
telecentric lens with a long working distance and a large
numerical aperture. The object space
telecentric lens comprises a front lens group, an aperture diaphragm and a rear lens group which are sequentially arranged from an object space to an image space along an
optical axis of the lens. The front lens group comprises a first lens with positive focal power, a second lens with positive focal power, a fourth lens with positive focal power, a sixth lens with positive focal power, an eighth lens with negative focal power, a third lens with negative focal power, a fifth lens with negative focal power, a seventh lens with negative focal power and a ninth lens with negative focal power, the eighth lens and the ninth lens form a second group of doublet lenses, and the fifth lens, the sixth lens and the seventh lens form a first group of triplet lenses. The rear lens group includes a tenth lens and a twelfth lens having positive refractive power, and an eleventh lens and a thirteenth lens having negative refractive power. According to the invention, the thirteen spherical glass lenses are adopted, and the focal power of each lens is reasonably distributed, so that the lens has the advantages of long working distance, large
numerical aperture,
ultrahigh resolution, high relative illumination, wide spectral range, high telecentricity and the like, and the problem of
low resolution of a long-working-distance object space
telecentric lens is solved. The
measurement precision of the detection lens is improved, and the requirements of some application scenes for higher-performance lenses are met.