Imaging lens system

An imaging lens system comprising:

• a first lens having positive refractive power;
• a second lens having negative refractive power;
• a third lens having a refractive power;
• a fourth lens having a convex object-side surface in a paraxial region thereof;
• a fifth lens having a refractive power;
• a sixth lens having a refractive power;
• and
• a seventh lens having negative refractive power,
• wherein the first to seventh lenses are sequentially disposed in order from an object side,
• wherein an absolute value of a radius of curvature of an object-side surface of the seventh lens is greater than an absolute value of a radius of curvature of an object-side surface of the second lens,
• wherein a distance from an image-side surface of the second lens to an object-side surface of the third lens is greater than a distance from an image-side surface of the fourth lens to an object-side surface of the fifth lens, and
• wherein 1.2<D23/D34, where D23 is a distance from an image-side surface of the second lens to an object-side surface of the third lens and D34 is a distance from an image-side surface of the third lens to an object-side surface of the fourth lens.