Imaging lens

An imaging lens comprising:

• a first lens group;
• a second lens group;
• and
• a third lens group having negative refractive power, arranged in this order from an object side to an image plane side,
• wherein said first lens group includes a first lens, a second lens, and a third lens having negative refractive power,
• said second lens group includes a fourth lens and a fifth lens,
• said third lens group includes a sixth lens and a seventh lens,
• said first lens is formed in a meniscus shape at a paraxial region thereof,
• said fourth lens is formed in a meniscus shape at a paraxial region thereof,
• said seventh lens is formed in a meniscus shape at a paraxial region thereof, and
• said second lens is disposed away from the third lens by a distance D23 on an optical axis thereof so that the following conditional expression is satisfied:
• 0.03<D23/f<0.2,
• where f is a focal length of a whole lens system.

An imaging lens comprising:

• a first lens group;
• a second lens group;
• and
• a third lens group having negative refractive power, arranged in this order from an object side to an image plane side,
• wherein said first lens group includes a first lens, a second lens, and a third lens,
• said second lens group includes a fourth lens and a fifth lens,
• said third lens group includes a sixth lens having positive refractive power and a seventh lens having negative refractive power,
• said fourth lens is formed in a meniscus shape at a paraxial region thereof,
• said seventh lens is formed in a meniscus shape at a paraxial region thereof,
• said seventh lens has a focal length f7, and
• said third lens is disposed away from the fourth lens by a distance D34 on an optical axis thereof so that the following conditional expressions are satisfied:
• −2.38≤f7/f<−0.8,
• 0.03<D34/f<0.2,
• where f is a focal length of a whole lens system.