Abstract: A pavement anti-skid performance evaluation method based on envelope feature is provided. A surface profile image of a to-be-tested piece is acquired as a blank background image. A motion trajectory image of a sliding piece on the to-be-tested piece is acquired. The blank background image is treated to obtain a surface texture profile curve of the to-be-tested piece. The motion trajectory image is differenced with the blank background image to obtain a difference image, which is treated to obtain a trajectory envelope curve of motion of the sliding piece on the to-be-tested piece. An arithmetic mean of the trajectory envelope curve and an arithmetic mean of the surface texture profile curve are calculated, and the anti-skid performance is evaluated based on a height difference ?h between above two arithmetic means. A pavement anti-skid performance evaluation device based on envelope feature is also provided.

Abstract: Provided a lithography projection objective includes: first lens group, second lens group, third lens group, fourth lens group, and fifth lens group, wherein first lens group, second lens group, third lens group, fourth lens group, and fifth lens group are sequentially arranged along an optical axis; first lens group and third lens group each has negative optical power, second lens group and fourth lens group each has positive optical power, fifth lens group has optical power of 0, sum optical power of first lens group, second lens group, third lens group, fourth lens group, and fifth lens group is 0; lithography projection objective further includes diaphragm; and first lens group, third lens group, and fourth lens group each comprises aspheric lenses, one aspheric lens thereof includes an aspherical surface; and a number of aspheric lenses is greater than or equal to 4 and less than or equal to 8.

Abstract: Provided a lithography projection objective includes: first lens group, second lens group, third lens group, fourth lens group, and fifth lens group, wherein first lens group, second lens group, third lens group, fourth lens group, and fifth lens group are sequentially arranged along an optical axis; first lens group and third lens group each has negative optical power, second lens group and fourth lens group each has positive optical power, fifth lens group has optical power of 0, sum optical power of first lens group, second lens group, third lens group, fourth lens group, and fifth lens group is 0; lithography projection objective further includes diaphragm; and first lens group, third lens group, and fourth lens group each comprises aspheric lenses, one aspheric lens thereof includes an aspherical surface; and a number of aspheric lenses is greater than or equal to 4 and less than or equal to 8.

Abstract: A projection objective, used for projecting an object space to an image space. The objective includes, from the object space along an optical axis in sequence: a first lens set (G1) having positive focal power, a second lens set (G2) having negative focal power, a third lens set (G3) having positive focal power, a fourth lens set (G4) having negative focal power, and a fifth lens set (G5) having positive focal power. Aspheric lenses are provided in the first lens set (G1), the second lens set (G2), the third lens set (G3), the fourth lens set (G4), and the fifth lens set (G5).

Abstract: A projection objective, used for projecting an object space to an image space. The objective includes, from the object space along an optical axis in sequence: a first lens set (G1) having positive focal power, a second lens set (G2) having negative focal power, a third lens set (G3) having positive focal power, a fourth lens set (G4) having negative focal power, and a fifth lens set (G5) having positive focal power. Aspheric lenses are provided in the first lens set (G1), the second lens set (G2), the third lens set (G3), the fourth lens set (G4), and the fifth lens set (G5).