Photographing lens and camera

1. A shooting lens comprising

at least three lens groups disposed in order from an object side, wherein:

an adhesion multiple-layer diffractive optical element is formed on one of surfaces disposed between an object surface and an imaging plane; and

a thickness d 1 on an optical axis of one of two layers in mutual adhesion of the adhesion multiple-layer diffractive optical element, a thickness d 2 on the optical axis of the other of the two layers, and a minimum grating pitch p of a diffractive optical surface of the adhesion multiple-layer diffractive optical element satisfy conditional expression (4) below

0.001 <p /( d 1+ d 2)<1.0  (4).

2. A shooting lens according to claim 1 , wherein

a maximum image height Y and an entire length L of the shooting lens satisfy conditional expression (1) below

0.1 <Y/L< 3.0  (1).

3. A shooting lens according to claim 1 , wherein

the thickness d 1 , the thickness d 2 , and a total thickness d (including d 1 and d 2 ) on the optical axis of the lens group as a formation location of the adhesion multiple-layer diffractive optical element satisfy conditional expression (2) below

0.02<( d 1+ d 2)/ d< 1.0  (2).

4. A shooting lens comprising according to claim 1 , wherein

a distance Z on the optical axis from the diffractive optical surface of the adhesion multiple-layer diffractive optical element to an aperture stop and a paraxial curvature radius R of a base surface on which the adhesion multiple-layer diffractive optical element is formed satisfy conditional expression (3) below

−2.0 <Z/R<− 0.3  (3).

5. The shooting lens according to claim 1 , wherein:

one of the two layers in mutual adhesion of the adhesion multiple-layer diffractive optical element is made of a high refractive index and small dispersion material, and the other is made of a low refractive index and large dispersion material; and

an Abbe number difference Δυd between the two layers and a refractive index difference ΔNd between the two layers satisfy conditional expression (5) below

50 <Δυd/ΔNd< 2000  (5).

6. The shooting lens according to claim 1 , wherein

a diffraction efficiency Ed for a d-line, a diffraction efficiency Eg for a g-line, and a diffraction efficiency EC for a C-line of the adhesion multiple-layer diffractive optical element satisfy conditional expression (6) below

( Eg+EC )/2>0.9 ×Ed   (6).

7. The shooting lens according to claim 1 , wherein

an incident angle θ at which a principal ray of a light flux directed to a maximum image height passing through the shooting lens is incident on the adhesion multiple-layer diffractive optical element satisfies a conditional expression (7) below

θ<10°  (7).

8. The shooting lens according to claim 1 , wherein

an effective diameter C of the adhesion multiple-layer diffractive optical element and a focal length f of a whole system of the shooting lens satisfy conditional expression (8) below

0.1 <C/f< 3.0  (8).

9. The shooting lens according to claim 1 , wherein

each of the three lens groups has a positive refractive power.

10. The shooting lens according to claim 1 , wherein

a radius of curvature R of the base surface on which the adhesion multiple-layer diffractive optical element is formed and the entire length L of the shooting lens satisfy conditional expression (9) below

0.05 <|R/L|   (9).

11. A camera comprising:

a shooting lens according to claim 1 ; and

an imaging device disposed near the imaging plane of the shooting lens.