An F-θ lens for laser engraving includes a first lens (L1), a second lens (L2), a third lens (L3), and a fourth lens (L4), which are coaxially arranged along a transmission direction of incident light; wherein the first lens (L1) is a meniscus lens, the second lens (L2) is a meniscus lens, the third lens (L3) is a plano-convex lens, and the fourth lens (L4) is a flat lens; wherein the first lens (L1) has a first surface (S1) and a second surface (S2), the second lens (L2) has a third surface (S3) and a fourth surface (S4), the third lens (L3) has a fifth surface (S5) and a sixth surface (S6), and the fourth lens (L4) has a seventh surface (S7) and an eighth surface (S8); the first surface (S1) to the eighth surface (S8) are sequentially arranged along the transmission direction of the incident light; wherein radii of curvature of the first surface (S1) to the eighth surface (S8) are −29 mm, −88 mm, −56 mm, −36 mm, ∞, −116 mm, ∞, and ∞, respectively; and center thicknesses (d1, d2, d3, d4) of the first lens (L1) to the fourth lens (L4) are 3 mm, 6 mm, 6 mm, and 3 mm, respectively.
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