Imaging lens
AssigneeGenius Electronic Optical Co., Ltd.
InventorShihhan Chen
Life of this patent
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Abstract
A four element lens system for use with an imaging sensor includes first, second, third, and fourth lens elements and an optical filter that are arranged sequentially in order from an object side to an imaging side. The lens elements are coated with an anti-reflective film. The lens system further includes an optical filter that is disposed at a distance from the imaging sensor. The lens elements are relatively positioned to each other to satisfy specific conditions. The lens elements further include thickness to diameters ratios that satisfy specific conditions.
Claims23
An imaging lens comprising first, second, third, and fourth lens elements arranged in order from an object side to an imaging side, each of the first, second, third, and fourth lens elements having an object-side surface facing toward the object side, and an imaging-side surface facing toward the imaging side, wherein the imaging lens satisfies the conditions of:
- 30<vd1−vd2;
- 0.5<d1avg/d2avg<0.9;
- and
- 0.4<d3avg/d4avg<0.7,
- wherein vd1 and vd2 are Abbe numbers of the respective first and second lens elements, and d1avg, d2avg, d3avg, and d4avg are average diameters of the first, second, third, and fourth lens elements, respectively;
- and
- wherein the imaging-side surface of the third lens element satisfies the following condition:
- 5.0<sag75/sag25<7.0,
- wherein sag25 is a sag value at a 25 percent point of a clear aperture of the imaging-side surface of the third lens element and sag75 is a sag value at a 75 percent point of the clear aperture of the imaging-side surface of the third lens element.
Dependencies are inferred from the claim text.