JP2023083485A5

JP2023083485A5 - Eyepiece optical system and imaging device

Info

Publication number: JP2023083485A5
Application number: JP2023069697A
Authority: JP
Filing date: 2023-04-21
Publication date: 2023-10-24

Description

本発明は、接眼光学系及び撮像装置に関する。 The present invention relates to an eyepiece optical system and an imaging device.

本発明の第一の態様に係る接眼光学系は、観察物体側から順に、正の屈折力を有する第１レンズと、負の屈折力を有する第２レンズと、正の屈折力を有する第３レンズと、正の屈折力を有する第４レンズと、を有し、次式の条件を満足する。
１．７００＜ｎｄ１＜１．８００
但し、
ｎｄ１：第１レンズの媒質のｄ線に対する屈折率 The eyepiece optical system according to the first aspect of the present invention includes, in order from the observation object side, a first lens having a positive refractive power, a second lens having a negative refractive power, and a third lens having a positive refractive power. and a fourth lens having positive refractive power, and satisfies the following condition.
1.700 < nd1 < 1.800
however,
nd1: refractive index of the medium of the first lens for the d-line

Claims

Starting from the observed object side,
a first lens having positive refractive power;
a second lens having negative refractive power;
a third lens having positive refractive power;
a fourth lens having positive refractive power;
An eyepiece optical system that satisfies the conditions of the following formula.
1.700 < nd1 < 1.800
however,
nd1: refractive index for the d-line of the medium of the first lens

The eyepiece optical system according to claim 1, which satisfies the following condition.
1.38 < fe/f1 < 3.00
however,
fe: Focal length of the entire eyepiece optical system f1: Focal length of the first lens

The eyepiece optical system according to claim 1 or 2, which satisfies the following condition.
0.48 < fe/f12 < 3.00
however,
fe: Focal length of the entire system of the eyepiece optical system f12: Combined focal length of the first lens and the second lens

4. The eyepiece optical system according to claim 1, wherein the eyepoint side lens surface of the lens closest to the eyepoint is convex toward the eyepoint.

The eyepiece optical system according to claim 1, wherein the second lens satisfies the following condition.
15.0 < νd2 < 35.0
however,
νd2: Abbe number for the d-line of the medium of the second lens

The eyepiece optical system according to any one of claims 1 to 5, which satisfies the following condition.
0.01 < fe/f4 < 0.33
however,
fe: Focal length of the entire eyepiece optical system f4: Focal length of the fourth lens

The eyepiece optical system according to any one of claims 1 to 6, which satisfies the following condition.
-0.30 < (G2R2-G3R1)/(G2R2+G3R1) < 0.50
however,
G2R2: Radius of curvature of the lens surface of the second lens closest to the eye point G3R1: Radius of curvature of the lens surface of the third lens closest to the observation object

The eyepiece optical system according to any one of claims 1 to 7, which satisfies the following condition.
-0.75 < (G1R2+G1R1)/(G1R2-G1R1) < 0.00
however,
G1R1: Radius of curvature of the lens surface of the first lens closest to the observation object G1R2: Radius of curvature of the lens surface of the first lens closest to the eye point

The eyepiece optical system according to any one of claims 1 to 8, which satisfies the following condition.
-1.00 < fe/EnP < -0.48
however,
fe: Focal length of the entire system of the eyepiece optical system EnP: Entrance pupil position of the eyepiece optical system at the standard diopter (signs are positive on the eyepoint side with the observation object plane as the reference)

The eyepiece optical system according to any one of claims 1 to 9, which satisfies the following condition.
-0.40 < fe/f23 < -0.15
however,
fe: Focal length of the entire system of the eyepiece optical system f23: Combined focal length of the second lens and the third lens

The eyepiece optical system according to any one of claims 1 to 10, which satisfies the following condition.
0.58 < D1/f1 < 0.90
however,
D1: Air equivalent distance from the observation object to the lens surface of the first lens closest to the observation object at the standard diopter f1: Focal length of the first lens

The eyepiece optical system according to any one of claims 1 to 11, which satisfies the following condition.
1.50 < TL/fe < 1.80
however,
TL: Total length of the eyepiece optical system fe: Focal length of the entire eyepiece optical system

The eyepiece optical system according to any one of claims 1 to 12, which satisfies the following condition.
1.640 < nd2 < 1.800
however,
nd2: refractive index for the d-line of the medium of the second lens

The eyepiece optical system according to any one of claims 1 to 13, wherein diopter adjustment is performed by moving the entire eyepiece optical system in the optical axis direction.

An imaging device comprising the eyepiece optical system according to any one of claims 1 to 14.