Small wide-angle full-glass lens

The invention discloses a small wide-angle all-glass lens which comprises a first lens group, a second lens group, a third lens group, a diaphragm and a fourth lens group which are sequentially arranged from an object side to an image side. According to the small wide-angle all-glass lens, the focal length is 2.4 mm, the aperture value is 1.8, the number of apertures is large, larger luminous flux can be obtained, the brightness of a whole picture is improved, the total length is within 30 mm, the total length is short, the maximum aperture of the whole lens is small, the requirement for the small size is met, meanwhile, the large view field angle is achieved, more view fields and information can be obtained, the resolving power is high, and the image quality is improved. The lens can be used for different object distances by fine tuning the focal power between the lens groups, and meanwhile, all the lenses of the small wide-angle all-glass lens are glass spherical surfaces, so that when the required number i