Ocular lens and imaging apparatus

1. An ocular lens consisting of, in order from an observation object side to an eye-point side:

a first lens group having a positive refractive power;

a second lens group having a positive or negative refractive power; and

a third lens group having a positive refractive power,

wherein the first lens group consists of one meniscus lens having a positive refractive power with a convex surface toward the eye-point side,

the second lens group includes at least one negative lens and at least one positive lens, and the number of lenses constituting the second lens group is three or less,

the third lens group consists of one meniscus lens having a positive refractive power with a convex surface toward the eye-point side, and

the following Conditional Expression (1) is satisfied,

0.8< f/TL< 1.1  (1)

where f is a focal length of the whole system, and

TL is a distance on an optical axis from a surface on the observation object side of the meniscus lens of the first lens group to a surface on the eye-point side of the meniscus lens of the third lens group.

2. The ocular lens according to claim 1 , wherein the following Conditional Expression (2) is satisfied,

0.78< TGL/TL< 0.97  (2)

where TGL is a total sum of central thicknesses of lenses of the whole system.

3. The ocular lens according to claim 1 , wherein the following Conditional Expression (3) is satisfied,

0.65<( R 1 f−R 1 r )/( R 1 f+R 1 r )<1  (3)

where R 1 f is a paraxial radius of curvature of a surface on the observation object side of the meniscus lens of the first lens group, and

R 1 r is a paraxial radius of curvature of a surface on the eye-point side of the meniscus lens of the first lens group.

4. The ocular lens according to claim 1 , wherein the following Conditional Expression (4) is satisfied,

0.01<( R 3 f−R 3 r )/( R 3 f+R 3 r )<0.3  (4)

where R 3 f is a paraxial radius of curvature of a surface on the observation object side of the meniscus lens of the third lens group, and

R 3 r is a paraxial radius of curvature of a surface on the eye-point side of the meniscus lens of the third lens group.

5. The ocular lens according to claim 1 , wherein the following Conditional Expression (5) is satisfied,

1.75<Npave<2  (5)

where Npave is an average value of refractive indices in a d line of positive lenses of the whole system.

6. The ocular lens according to claim 1 , wherein the following Conditional Expression (6) is satisfied,

0.01< N max− N min<0.35  (6)

where Nmax is a maximum value of refractive indices in the d line of lenses of the whole system, and

Nmin is a minimum value of refractive indices in the d line of the lenses of the whole system.

7. The ocular lens according to claim 1 , wherein the second lens group consists of three lenses.

8. The ocular lens according to claim 1 , wherein the second lens group consists of two lenses.

9. The ocular lens according to claim 1 , wherein the following Conditional Expression (1-1) is satisfied

0.9< f/TL< 1  (1-1).

10. The ocular lens according to claim 2 , wherein the following Conditional Expression (2-1) is satisfied

0.8< TGL/TL< 0.95  (2-1).

11. The ocular lens according to claim 3 , wherein the following Conditional Expression (3-1) is satisfied

0.7<( R 1 f−R 1 r )/( R 1 f+R 1 r )<0.95  (3-1).

12. The ocular lens according to claim 4 , wherein the following Conditional Expression (4-1) is satisfied

0.05<( R 3 f−R 3 r )/( R 3 f+R 3 r )<0.25  (4-1).

13. The ocular lens according to claim 5 , wherein the following Conditional Expression (5-1) is satisfied

1.8<Npave<1.95  (5-1).

14. The ocular lens according to claim 6 , wherein the following Conditional Expression (6-1) is satisfied

0.05< N max− N min<0.3  (6-1).

15. An imaging apparatus comprising the ocular lens according to claim 1 .