JP2013218239A - Stereoscopic imaging optical system and endoscope equipped with the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a stereoscopic imaging optical system capable of being reduced in dimension in the direction of an optical axis while improving performance, and an endoscope equipped with the same.SOLUTION: A stereoscopic imaging optical system comprises: a front lens group Gf having a single optical axis; a rear lens group Gr having a single optical axis, arranged on the same axis as the front lens group Gf; a pupil division part 2 disposed between the front lens group Gf and the rear lens group Gr and able to divide a luminous flux; and a deflecting part 3 disposed between the front lens group Gr and the rear lens group Gr and configured to deflect a luminous flux. The pupil division part 2 can be switched between the state of a stereoscopic view close point at which a luminous flux is divided by at least two apertures and the state of a stereoscopic view distant point at which a luminous flux is divided by at least two apertures separated more widely than the state of the stereoscopic view close point.

Description

  The present invention relates to a stereoscopic imaging optical system capable of stereoscopic observation and an endoscope including the same.

  Conventionally, an optical system that forms two images with different parallax on a substantially identical plane for stereoscopic viewing has been disclosed (see Patent Documents 1 and 2).

  The technique described in Patent Document 1 performs pupil division on a reflecting surface, and changes the angle of convergence by changing the interval between the centers of gravity of light fluxes by widening or narrowing a single aperture. .

Japanese Patent No. 3283084

  However, with the technique described in Patent Document 1, the convergence angle cannot be changed greatly, and the stereoscopic effect changes depending on whether the distance to the object is far or near. In addition, since the opening is widened or narrowed, the brightness also changes. In order to obtain a bright optical system with this technique, the total length becomes long and the optical system becomes large.

  An object of the present invention is to provide a stereoscopic imaging optical system capable of forming a size in the optical axis direction in a small size while improving performance and an endoscope including the same.

  A stereoscopic imaging optical system according to an embodiment of the present invention includes a front lens group having a single optical axis, a rear lens group having a single optical axis arranged coaxially with the front lens group, and the front lens group. A pupil division unit arranged between a lens group and the rear lens group and capable of dividing a light beam; and a deflection unit arranged between the front lens group and the rear lens group to deflect the light beam, The pupil dividing unit can be switched between a stereoscopic near-point state in which the light beam is divided by at least two openings and a stereoscopic far-point state in which the light is divided by at least two openings that are wider than the stereoscopic near-point state. It is characterized by being.

  In one embodiment of the present invention, the deflection unit is disposed adjacent to the rear lens group side of the pupil division unit.

  In one embodiment of the present invention, the deflection unit deflects the light beams divided by the pupil division unit so as to intersect each other in the rear lens group.

  In one embodiment of the present invention, the pupil division unit can be switched to a monocular viewing state in which a light beam passes through one opening.

  Furthermore, an endoscope according to an embodiment of the present invention includes the stereoscopic imaging optical system and an imaging element having an imaging surface disposed on the image side of the stereoscopic imaging optical system. .

  According to the stereoscopic imaging optical system and the endoscope including the same according to an embodiment of the present invention, it is possible to reduce the size in the optical axis direction while improving the performance.

It is sectional drawing of the three-dimensional imaging optical system of 1st Embodiment. It is a figure which shows the pupil division part of the three-dimensional imaging optical system of 1st Embodiment. It is a figure which shows the pupil division part in the monocular viewing state of the three-dimensional imaging optical system of 1st Embodiment. It is a figure which shows the pupil division part in the stereoscopic vision near point state of the stereoscopic imaging optical system of 1st Embodiment. It is a figure which shows the pupil division part in the stereoscopic vision far point state of the stereoscopic imaging optical system of 1st Embodiment. It is a figure which shows an example of the deflection | deviation part of the three-dimensional imaging optical system of 1st Embodiment. It is a figure which shows the monocular vision state of the stereoscopic imaging optical system of 1st Embodiment, a stereoscopic vision near point state, and a stereoscopic vision far point state. It is an aberration diagram of the monocular viewing state of the stereoscopic imaging optical system of the first embodiment. It is an aberration diagram of the monocular viewing state of the stereoscopic imaging optical system of the first embodiment. It is an aberration diagram of the stereoscopic vision near point state of the stereoscopic imaging optical system of the first embodiment. It is an aberration diagram of the stereoscopic vision near point state of the stereoscopic imaging optical system of the first embodiment. It is an aberration diagram of the stereoscopic vision far point state of the stereoscopic imaging optical system of the first embodiment. It is an aberration diagram of the stereoscopic vision far point state of the stereoscopic imaging optical system of the first embodiment. It is sectional drawing of the three-dimensional imaging optical system of 2nd Embodiment. It is a figure which shows the pupil division part of the three-dimensional imaging optical system of 2nd Embodiment. It is a figure which shows the pupil division part of the three-dimensional imaging optical system of 2nd Embodiment. It is a figure which shows the pupil division part in the monocular viewing state of the three-dimensional imaging optical system of 2nd Embodiment. It is a figure which shows the pupil division part in the stereoscopic vision near point state of the stereoscopic imaging optical system of 2nd Embodiment. It is a figure which shows the pupil division part in the stereoscopic vision far point state of the stereoscopic imaging optical system of 2nd Embodiment. It is a figure which shows an example of the deflection | deviation part of the three-dimensional imaging optical system of 2nd Embodiment. It is a figure which shows the monocular viewing state and stereoscopic viewing state of the stereoscopic imaging optical system of 2nd Embodiment. It is an aberration diagram of the monocular viewing state of the stereoscopic imaging optical system of the second embodiment. It is an aberration diagram of the monocular viewing state of the stereoscopic imaging optical system of the second embodiment. It is an aberration diagram of the stereoscopic vision state of the stereoscopic imaging optical system of the second embodiment. It is an aberration diagram of the stereoscopic vision state of the stereoscopic imaging optical system of the second embodiment. It is sectional drawing of the three-dimensional imaging optical system of 3rd Embodiment. It is a figure which shows an example of the opening member of the pupil division part of the three-dimensional imaging optical system of 3rd Embodiment. It is a figure which shows the slit member of the pupil division part of the three-dimensional imaging optical system of 3rd Embodiment. It is a figure which shows the pupil division part in the stereoscopic vision near point state of the stereoscopic imaging optical system of 3rd Embodiment. It is a figure which shows the pupil division part in the stereoscopic vision far point state of the stereoscopic imaging optical system of 3rd Embodiment. It is a figure which shows an example of the deflection | deviation part of the three-dimensional imaging optical system of 3rd Embodiment. It is a figure which shows the other example of the aperture member of the pupil division part of the three-dimensional imaging optical system of 3rd Embodiment. It is a figure which shows the pupil division part of the other example of the stereoscopic vision near point state of the stereoscopic imaging optical system of 3rd Embodiment. It is a figure which shows the pupil division part of the other example of the stereoscopic vision far point state of the stereoscopic imaging optical system of 3rd Embodiment. It is a figure which shows the other example of the deflection | deviation part of the three-dimensional imaging optical system of 3rd Embodiment. It is a figure which shows the stereoscopic vision near point state and stereoscopic vision far point state of the stereoscopic imaging optical system of 3rd Embodiment. It is an aberration diagram of the stereoscopic vision near point state of the stereoscopic imaging optical system of the third embodiment. It is an aberration diagram of the stereoscopic vision near point state of the stereoscopic imaging optical system of the third embodiment. It is an aberration diagram of the stereoscopic vision far point state of the stereoscopic imaging optical system of the third embodiment. It is an aberration diagram of the stereoscopic vision far point state of the stereoscopic imaging optical system of the third embodiment. It is sectional drawing of the three-dimensional imaging optical system of 4th Embodiment. It is a figure which shows an example of the deflection | deviation part of the three-dimensional imaging optical system of 4th Embodiment. It is a figure which shows the stereoscopic vision near point state and stereoscopic vision far point state of the stereoscopic imaging optical system of 4th Embodiment. It is an aberration diagram of the stereoscopic vision near point state of the stereoscopic imaging optical system of the fourth embodiment. It is an aberration diagram of the stereoscopic vision near point state of the stereoscopic imaging optical system of the fourth embodiment. It is an aberration diagram of the stereoscopic vision far point state of the stereoscopic imaging optical system of the fourth embodiment. It is an aberration diagram of the stereoscopic vision far point state of the stereoscopic imaging optical system of the fourth embodiment.

  A stereoscopic imaging optical system according to an embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a cross-sectional view of the stereoscopic imaging optical system according to the first embodiment.

  The stereoscopic imaging optical system 1 according to the first embodiment includes a front lens group Gf having a single optical axis Lc, a rear lens group Gr arranged coaxially with the front lens group Gf and having a single optical axis Lc, It is arranged between the front lens group Gf and the rear lens group Gr, and the monocular viewing state in which one opening is formed, the stereoscopic near point state in which at least two openings are formed, and the distance between the apertures are more than in the stereoscopic near point state. A pupil division unit 2 that can be switched to a wide stereoscopic vision far point state, and a prism deflection unit 3 that is arranged corresponding to the pupil division unit 2 and deflects a light beam.

The front lens group Gf includes, in order from the object side to the image side, a plano-concave negative lens L _f1 having a plane facing the object side, a negative meniscus lens L _f2 having a convex surface facing the image side, and a biconvex positive lens L _f3 And a positive meniscus lens L _f4 having a convex surface facing the object side.

  The front lens group Gf is effective in increasing the angle of view by disposing at least two lenses having negative refractive power on the object side, thereby reducing the focal length of the front lens group Gf. Further, by making the object side surface of the lens having a negative refractive power on the object side flat, it is possible to reduce adhesion of dirt and the like.

The rear lens group Gr, in order from the object side to the image side, is a cemented lens SU _r1 of a biconcave negative lens L _r1 and a biconvex positive lens L _r2 , and a negative surface with a convex surface facing the biconvex positive lens L _r3 and the image surface side. It has a cemented lens SU _r2 of the meniscus lens L _r4 and a positive meniscus lens L _r5 with a convex surface facing the object side.

  In front of the image plane I, a filter F and a cover glass C are arranged.

  FIG. 2 is a diagram illustrating a pupil division unit of the stereoscopic imaging optical system according to the first embodiment. FIG. 3 is a diagram illustrating a pupil division unit in the monocular viewing state of the stereoscopic imaging optical system according to the first embodiment. Furthermore, FIG. 4 is a diagram illustrating the pupil division unit in the stereoscopic near-point state of the stereoscopic imaging optical system according to the first embodiment. FIG. 5 is a diagram illustrating the pupil division unit in the stereoscopic far-end state of the stereoscopic imaging optical system according to the first embodiment.

  The pupil division unit 2 forms an opening by a patterned electrochromic element or an electronic element such as a liquid crystal shutter. As shown in FIG. 2, for example, the pupil division unit 2 includes a monocular viewing state in which one opening 2 a is formed, a stereoscopic near-point state and an opening in which at least two openings 2 b having an interval in the first direction A are formed. The openings are respectively patterned in advance so as to form openings corresponding to the stereoscopic far point state in which the interval in the first direction X of 2c is wider than that in the second state in accordance with predetermined electrodes. Portions other than the aperture are used to block unnecessary light flux.

  For example, in the first state, as shown in FIG. 3, the pupil division unit 2 forms one opening 2a corresponding to the normal monocular viewing state. Further, in the stereoscopic near-point state, the pupil dividing unit 2 forms two openings 2b corresponding to the stereoscopic near-point state as shown in FIG. Further, in the stereoscopic far point state, as shown in FIG. 5, the pupil dividing unit 2 has two openings 2c corresponding to the stereoscopic far point state having a wider interval than the two openings 2b in the stereoscopic near point state. Form.

  As described above, since the normal monocular viewing state, the stereoscopic viewing near point state, and the stereoscopic viewing far point state can be switched, the state of the optical system can be selected according to the situation. It becomes possible to make the stereoscopic imaging optical system of a form excellent in functionality. Moreover, since the opening is formed by an electronic element such as a patterned electrochromic element or a liquid crystal shutter, it is not necessary to provide a mechanical movement mechanism, and the endoscope or the like can be applied to an endoscope or the like. It becomes possible to reduce the size.

  FIG. 6 is a diagram illustrating an example of a deflection unit of the stereoscopic imaging optical system according to the first embodiment.

  As shown in FIG. 6, the prism deflection unit 3 has a first surface 3 a formed of a plane, and a second surface 3 b opposite to the first surface 3 a, and the second surface 3 b is The thickness in the optical axis direction with respect to the first surface 3a is the smallest on the optical axis Lc, and is inclined so as to increase in thickness in the first direction A perpendicular to the optical axis from the optical axis Lc. .

  By adopting such a configuration of the prism deflection unit 3, the two optical paths divided by the pupil division unit 2 can be shifted so that the images do not overlap when the rear group forms an image. It becomes possible to form an image with the light beams in parallel. Furthermore, since the telecentricity on the image plane side is improved by separating the light beams from each other by the prism deflecting unit 3, it is preferable when using an imaging device having a sensitive incident angle characteristic.

  Further, by arranging the prism deflecting unit 3 adjacent to the pupil dividing unit 2 on the optical path, the light flux is narrowed down, and the stereoscopic imaging optical system can be downsized. The prism deflecting unit 3 may be arranged on either the object side or the image plane side of the pupil dividing unit 2 on the optical path.

  FIG. 7 is a diagram illustrating a monocular viewing state, a stereoscopic viewing near point state, and a stereoscopic viewing far point state of the stereoscopic imaging optical system according to the first embodiment. FIG. 7A is a diagram illustrating a monocular viewing state of the stereoscopic imaging optical system according to the first embodiment, and FIG. 7B is a stereoscopic viewing near point state of the stereoscopic imaging optical system according to the first embodiment. FIG. 7C is a diagram illustrating a stereoscopic far point state of the stereoscopic imaging optical system according to the first embodiment.

  As shown in FIG. 7A, in the monocular viewing state of the stereoscopic imaging optical system of the first embodiment, the prism deflection unit 3 is replaced with a flat plate 3 '. The structure for exchanging the prism deflection unit 3 and the flat plate 3 ′ is, for example, arranged such that the prism deflection unit 3 and the flat plate 3 ′ are arranged in the first direction A orthogonal to the optical axis shown in FIG. The structure etc. which switch by moving in the state which carried out are preferable.

  In the state where the prism deflection unit 3 shown in FIG. 6 is installed as it is, a convex prism or the like is installed on the object side that matches the concave shape of the second surface 3b of the prism deflection unit 3 to form a flat plate. It is good also as composition to do.

  8 and 9 are aberration diagrams of the stereoscopic imaging optical system according to the first embodiment in the monocular viewing state. FIGS. 10 and 11 are aberration diagrams of the stereoscopic near-point state of the stereoscopic imaging optical system according to the first embodiment. Further, FIGS. 12 and 13 are aberration diagrams of the stereoscopic imaging optical system according to the first embodiment in a stereoscopic viewing point state.

  These aberration diagrams show 656.3 nm (C line: broken line), 587.6 nm (d line: solid line), and 486.1 nm (F) in the X direction and Y direction, respectively, at the angle of view shown in the parentheses at the center. Lines: dashed lines) for each wavelength. The same applies to the aberration diagrams.

  FIG. 14 is a cross-sectional view of the stereoscopic imaging optical system of the second embodiment.

  The stereoscopic imaging optical system 1 according to the second embodiment includes a front lens group Gf having a single optical axis Lc, a rear lens group Gr arranged coaxially with the front lens group Gf and having a single optical axis Lc, A pupil division unit 12 disposed between the front lens group Gf and the rear lens group Gr and capable of switching between a monocular state in which one aperture is formed and a stereoscopic state in which at least two apertures are formed; And a prism deflector 13 that deflects the light beam.

The front lens group Gf includes, in order from the object side to the image side, a plano-concave negative lens L _f1 having a plane facing the object side, a negative meniscus lens L _f2 having a convex surface facing the image side, and a biconvex positive lens L _f3 And a positive meniscus lens L _f4 having a convex surface facing the object side.

  The front lens group Gf is effective in increasing the angle of view by disposing at least two lenses having negative refractive power on the object side, thereby reducing the focal length of the front lens group Gf. Further, by making the object side surface of the lens having a negative refractive power on the object side flat, it is possible to reduce adhesion of dirt and the like.

The rear lens group Gr, in order from the object side to the image side, is a cemented lens SU _r1 of a biconcave negative lens L _r1 and a biconvex positive lens L _r2 , and a negative surface with a convex surface facing the biconvex positive lens L _r3 and the image surface side. It has a cemented lens SU _r2 of the meniscus lens L _r4 and a positive meniscus lens L _r5 with a convex surface facing the object side.

  In front of the image plane I, a filter F and a cover glass C are arranged.

15 and 16 are diagrams illustrating a pupil division unit of the stereoscopic imaging optical system according to the second embodiment. FIG. 17 is a diagram illustrating a pupil division unit in the monocular viewing state of the stereoscopic imaging optical system according to the second embodiment. Further, FIG. 18 is a diagram illustrating a pupil division unit in the stereoscopic near-point state of the stereoscopic imaging optical system according to the second embodiment. FIG. 19 is a diagram illustrating a pupil division unit in the stereoscopic far point state of the stereoscopic imaging optical system according to the second embodiment.

The pupil division unit 12 includes a first diaphragm plate 12 ₁ having an opening 12 ₁ a as shown in FIG. 15 and a second diaphragm plate 12 ₂ having an opening 12 ₂ a as shown in FIG. . The first diaphragm plate 12 ₁ and the second diaphragm plate 12 _{2 each} have an opening 12 ₁ a and 12 ₂ a at the center of a circular plate-shaped member, and a notch 12 ₁ d, The shape has 12 ₂ d. The first diaphragm plate 12 ₁ and the second diaphragm plate 12 ₂ are preferably line-symmetrical. The first diaphragm plate 12 ₁ and the second diaphragm plate 12 ₂ have rotation holes 12 ₁ e and 12 ₂ e in the vicinity of the notches 12 ₁ d and 12 ₂ d, respectively.

In the monocular viewing state in which one opening 12a is formed, as shown in FIG. 17, the pupil dividing unit 12 connects the first diaphragm plate 12 ₁ and the second diaphragm plate 12 ₂ to the rotation holes 12 ₁ e, 12. ₂ e are arranged so that they overlap, and the first diaphragm plate 12 ₁ and the second diaphragm plate 12 ₂ are arranged so that the respective openings 12 ₁ a and 12 ₂ a overlap on the optical axis.

Then, as shown in FIG. 18, from the monocular state, the first diaphragm plate 12 ₁ is rotated in the direction of the arrow B1a around the rotation hole 12 ₁ e, and the first aperture plate 12 ₂ e is centered around the rotation hole 12 ₂ e. By rotating the _two diaphragm plates 12 ₂ in the direction of the arrow B2a, a stereoscopic near-point state is formed in which at least two openings 12b having an interval in the first direction A are formed. In the stereoscopic near-point state, the first diaphragm plate 12 ₁ and the second diaphragm plate 12 ₂ are arranged so that the openings 12 ₁ a and 12 ₂ a do not overlap each other.

Thereafter, as shown in FIG. 19, from the stereoscopic near point state, the first diaphragm plate 12 ₁ is further rotated in the direction of the arrow B1b around the rotation hole 12 ₁ e, and the rotation hole 12 ₂ e is moved. center by rotating movement the second aperture plate 12 ₂ in the direction of arrow B2b, stereoscopic far point to form at least two openings 12c have a wider interval than the stereoscopic near point state in the first direction a Configure state.

In the second embodiment, the first stop plate 12 ₁ and in accordance with the rotation angle of the second stop plate 12 _2, the first stop plate 12 ₁ of the opening 12 ₁ a and the second diaphragm plate 12 _second opening It is possible to make the distance from 12 ₂ a variable.

  Therefore, in the monocular viewing state, the pupil division unit 12 forms one opening 12a corresponding to the normal monocular viewing state, as shown in FIG. In the stereoscopic near point state, the pupil division unit 12 forms two openings 12b corresponding to the stereoscopic near point state as shown in FIG. Further, in the stereoscopic far point state, the pupil dividing unit 12 forms two openings 12c corresponding to the stereoscopic far point state, as shown in FIG.

As described above, since the normal monocular viewing state, the stereoscopic near point state, and the stereoscopic far point state can be switched, the state of the optical system can be selected according to the situation, and the second embodiment It becomes possible to make the stereoscopic imaging optical system of a form excellent in functionality.
Further, since the opening is formed by the first diaphragm plate 12 ₁ and the second diaphragm plate 12 _2, it can be easily manufactured with a simple structure, and the cost can be reduced. Additionally, first diaphragm plate 12 ₁ and in accordance with the rotation angle of the second stop plate 12 _2, the first stop plate 12 ₁ and the opening 12 ₁ a and the second diaphragm plate 12 _{and second} opening 12 ₂ a Since the interval can be made variable, the functionality can be further improved.

  FIG. 20 is a diagram illustrating an example of a deflection unit of the stereoscopic imaging optical system according to the second embodiment.

As shown in FIG. 20, the prism deflection unit 13 has a first surface 13a formed of a flat surface and a second surface 13b opposite to the first surface 13a. The second surface 13b has a plane 13b ₁ near the optical axis Lc corresponding to one opening 12a in the first state shown in FIG. 17, and both sides thereof in the first direction A are in contact with the first surface 13a. It is formed as an inclined surface 13b ₂ that is inclined so that its thickness in the optical axis direction is the thinnest on the side close to the optical axis Lc, and becomes thicker as it moves away from the optical axis Lc in the first direction A.

That is, in the monocular viewing state, the light beam passes through the plane 13b ₁ of the second surface 13b of the prism deflecting unit 13, and in the stereoscopic near point state and the stereoscopic far point state, the second surface 13b of the prism deflecting unit 13 is used. light beam inclined surface 13b ₂ of the passes.

  By configuring the prism deflection unit 3 in such a configuration, in the monocular viewing state, the pupil dividing unit 12 forms an image on the optical axis of the image plane without dividing the optical path, and the stereoscopic near point state and the stereoscopic far point state. When the rear group images the two optical paths divided by the pupil dividing unit 12, the images can be shifted so that the images do not overlap, and two light beams can be imaged in parallel on the image plane. .

  Further, by arranging the prism deflecting unit 13 adjacent to the pupil dividing unit 12 on the optical path, the light flux is narrowed down, and the stereoscopic imaging optical system can be downsized. The prism deflecting unit 3 may be arranged on either the object side or the image plane side of the pupil dividing unit 2 on the optical path.

  FIG. 21 is a diagram illustrating a monocular viewing state and a stereoscopic viewing state of the stereoscopic imaging optical system according to the second embodiment. FIG. 21A is a diagram illustrating a monocular viewing state of the stereoscopic imaging optical system of the second embodiment, and FIG. 21B is a diagram illustrating a stereoscopic viewing state of the stereoscopic imaging optical system of the first embodiment. is there.

As shown in FIG. 21A, in the monocular viewing state of the stereoscopic imaging optical system of the second embodiment, the light beam passes through the flat surface 13b ₁ of the second surface 13b of the prism deflection unit 13. This is achieved by setting the pupil division unit 12 to a monocular viewing state, which is a monocular state, as shown in FIG.

In addition, as shown in FIG. 21B, in the stereoscopic viewing state of the stereoscopic imaging optical system of the second embodiment, the light beams pass through the inclined surface 13b ₂ of the second surface 13b of the prism deflector 13 respectively. . This is achieved by setting the pupil division unit 12 to the stereoscopic state as shown in FIG.

  22 and 23 are aberration diagrams in the monocular viewing state of the stereoscopic imaging optical system according to the second embodiment. 24 and 25 are aberration diagrams of the stereoscopic imaging optical system according to the second embodiment in the stereoscopic viewing state.

  FIG. 26 is a cross-sectional view of the stereoscopic imaging optical system of the third embodiment.

  The stereoscopic imaging optical system 1 according to the third embodiment includes a front lens group Gf having a single optical axis Lc, a rear lens group Gr arranged coaxially with the front lens group Gf and having a single optical axis Lc, It is arranged between the front lens group Gf and the rear lens group Gr, and can switch to a stereoscopic near point state that forms at least two apertures and a stereoscopic far point state in which the distance between the apertures is wider than the stereoscopic near point state. A pupil dividing unit 22 and a prism deflecting unit 23 arranged corresponding to the pupil dividing unit 22 to deflect a light beam are provided.

The front lens group Gf includes, in order from the object side to the image side, a plano-concave negative lens L _f1 having a flat surface facing the object side, a positive meniscus lens L _f2 having a convex surface facing the image surface side, and a convex surface facing the image surface side. A negative meniscus lens L _f3 that is directed, a positive meniscus lens L _f4 that has a convex surface facing the object side, and a positive meniscus lens L _f5 that has a convex surface facing the object side.

  The front lens group Gf is effective in increasing the angle of view by disposing at least two lenses having negative refractive power on the object side, thereby reducing the focal length of the front lens group Gf. Further, by making the object side surface of the lens having a negative refractive power on the object side flat, it is possible to reduce adhesion of dirt and the like.

The rear lens group Gr includes, in order from the object side to the image side, a cemented lens SU _{r1 of} a positive meniscus lens L _r1 having a convex surface facing the image surface side and a negative meniscus lens L _r2 having a convex surface facing the image surface side, and the object side A positive meniscus lens L _r3 having a convex surface facing the surface, a positive meniscus lens L _r4 having a convex surface facing the object side, and a negative meniscus lens L _r5 having a convex surface facing the object side.

  In front of the image plane I, a filter F and a cover glass C are arranged.

  FIG. 27 is a diagram illustrating an example of the aperture member of the pupil division unit of the stereoscopic imaging optical system according to the third embodiment. FIG. 28 is a diagram illustrating a slit member of the pupil division unit of the stereoscopic imaging optical system according to the third embodiment.

The pupil division unit 22 includes an opening member 22 ₁ and a slit member 22 ₂ .

The opening member 22 ₁ has at least two first openings 22 ₁ a spaced in the first direction A 1 and a second direction A 2 different from the first direction A ₁ than the first opening 22 ₁ a. And at least two second openings 22 ₁ b having a wide interval. In the third embodiment, the direction in which the _first openings 22 ₁ a are arranged and the direction in which the second openings 22 ₁ b are arranged are orthogonal to each other. The opening member 22 ₁ is configured to be rotatable about the optical axis Lc.

As shown in FIG. 28, the slit member 22 ₂ has a slit portion 22 ₂ a extending in the first direction A1. The slit portion 22 ₂ a has a width corresponding to the first opening 22 ₁ a and the second opening 22 ₁ b of the opening member 22 ₁ . In particular, the width of the slit portion 22 ₂ a is preferably greater than or equal to the diameters of the first opening 22 ₁ a and the second opening 22 ₁ b.

  FIG. 29 is a diagram illustrating a pupil dividing unit in a stereoscopic near-point state of the stereoscopic imaging optical system according to the third embodiment. FIG. 30 is a diagram illustrating a pupil division unit in the stereoscopic far point state of the stereoscopic imaging optical system according to the third embodiment.

As shown in FIGS. 29 and 30, the opening member 22 ₁ and the slit member 22 ₂ are arranged so as to overlap with the center of the optical axis Lc. As shown in FIG. 29, when the first opening 22 ₁ a overlaps the slit portion 22 ₂ a of the slit member 22 ₂ , the light beam passes through the first opening 22 ₁ a and is in a stereoscopic near-point state. Form. In addition, as shown in FIG. 30, when the opening member 22 ₁ rotates and the second opening 22 ₁ b overlaps with the slit portion 22 ₂ a of the slit member 22 ₂ , the light beam passes through the second opening 22. ₁ b passes through and forms a stereoscopic far point state.

  Thus, since the stereoscopic vision near point state and the stereoscopic vision far point state can be switched, the state of the optical system can be selected according to the situation, and the stereoscopic imaging optical system of the third embodiment can be selected. It becomes possible to make it excellent in functionality.

  FIG. 31 is a diagram illustrating an example of a deflection unit of the stereoscopic imaging optical system according to the third embodiment.

As shown in FIG. 31, the prism deflection unit 23 has a first surface 23a formed of a flat surface and a second surface 23b opposite to the first surface 23a. The second surface 23b has a first convex portion 23b ₁ at a position corresponding to the first opening 22 ₁ a of the opening member 22 ₁ shown in FIG. 27, and corresponds to the second opening 22 ₁ b. a position having a second convex portion 23b _2. The first convex portion 23b ₁ and the second convex portion 23b ₂ have the smallest thickness in the optical axis direction from the second surface 23b on the side close to the optical axis Lc, and become thicker as they are separated from the optical axis Lc. It is formed so as to be inclined.

The prism deflection unit 23 is configured to be rotatable integrally with the opening member 22 ₁ . That is, the second convex opening member 22 ₁ of the first opening 22 ₁ a and the first protrusion 23b ₁ and the opening member 22 ₁ of the second opening 22 ₁ b and the prism deflection unit 23 of the prism deflection unit 23 The portions 23b ₂ can be rotated in a corresponding state.

  By adopting such a configuration of the prism deflection unit 3, the two optical paths divided by the pupil division unit 2 can be shifted so that the images do not overlap when the rear group forms an image. It becomes possible to form an image with the light beams in parallel. Furthermore, since the telecentricity on the image plane side is improved by separating the light beams from each other by the prism deflecting unit 3, it is preferable when using an imaging device having a sensitive incident angle characteristic.

Further, by arranging the prism deflecting unit 3 adjacent to the pupil dividing unit 2 on the optical path, the light flux is narrowed down, and the stereoscopic imaging optical system can be downsized. In the third embodiment, from the object side on the optical axis, the slit member 22 _{2 of} the pupil division unit 2, the opening member 22 ₁ of the pupil division unit 2, the first surface 23 a of the prism deflection unit 3, and the first of the prism deflection unit 3. The two surfaces 23b are arranged in this order. Then, the aperture member 22 ₁ of the pupil division unit 2 and the prism deflection unit 3 are configured to be able to rotate integrally. The prism deflecting unit 3 may be arranged on either the object side or the image plane side of the pupil dividing unit 2 on the optical path.

  FIG. 32 is a diagram illustrating another example of the aperture member of the pupil division unit of the stereoscopic imaging optical system according to the third embodiment.

Pupil division unit 22 of another embodiment is comprised of the slit member 22 ₂ which shows the opening member 22 ₁₁ and 28 shown in FIG. 32.

The opening member 22 ₁₁ has an interval in the first direction A1, and at least two openings 22 ₁₁ having an interval narrower than the interval in the first direction A1 in the second direction A2 different from the first direction A1. c. In the third embodiment, the first direction A1 and the second direction A2 are orthogonal to each other. The opening member 22 ₁₁ is configured to be rotatable about the optical axis Lc.

As the slit member 22 ₂ , the one shown in FIG. 28 is used.

  FIG. 33 is a diagram illustrating a pupil division unit of another example of the stereoscopic near-point state of the stereoscopic imaging optical system according to the third embodiment. FIG. 34 is a diagram illustrating another example of the pupil division unit of the stereoscopic vision far point state of the stereoscopic imaging optical system according to the third embodiment.

The opening member 22 ₁₁ and the slit member _222, as shown in FIGS. 33 and 34, together centered on the optical axis Lc, is arranged to overlap. As shown in FIG. 33, when the opening member 22 ₁₁ rotates and the narrow portion of the opening 22 ₁₁ c overlaps with the slit portion 22 ₂ a of the slit member 22 ₂ , the light beam passes through the opening 22 ₁₁ c. A stereoscopic near-point state is formed by passing through a narrow interval. As shown in FIG. 34, when the opening member 22 ₁₁ rotates and the wide portion of the opening 22 ₁₁ c overlaps with the slit portion 22 ₂ a of the slit member 22 ₂ , the light beam passes through the opening 22 ₁₁ c. A stereoscopic far point state is formed by passing through a wide interval portion.

Further, between the narrow portion and the wide portion of the interval of the opening 22 ₁₁ c is formed so that the distance with the rotation of the opening member 22 ₁₁ is gradually changed continuously. Therefore, it is possible to continuously change the state of the stereoscopic between with the rotation of the opening member 22 ₁₁ from the stereoscopic near point state of the far point state stereoscopic.

  As described above, the pupil division unit according to another example of the third embodiment can continuously change the stereoscopic state between the stereoscopic near point state and the stereoscopic far point state. Accordingly, the state of the optical system can be selected, and the stereoscopic imaging optical system of the third embodiment can be made excellent in functionality.

  FIG. 35 is a diagram illustrating another example of the deflection unit of the stereoscopic imaging optical system according to the third embodiment.

As shown in FIG. 35, a prism deflection unit 23 suitable for use in the pupil division unit 22 of another example of the third embodiment shown in FIG. It has the 2nd surface 23b on the opposite side to the surface 23a. The second surface 23b has an inclined surface 23b ₁₁ at a position corresponding to the opening 22 ₁₁ c of the opening member 22 ₁₁ shown in FIG. 32.

The inclined surface 23b ₁₁ is thickened at a position corresponding to a portion where the interval between the openings 22 ₁₁ c of the opening member 22 ₁₁ is narrow, and reaches the position corresponding to a portion where the interval between the openings 22 ₁₁ c of the opening member 22 ₁₁ is wide. Are formed so as to be continuously thinner. A step portion 23b ₁₁ is formed at the boundary between the two inclined surfaces 23b ₁₁ .

The prism deflection unit 23 is configured to be rotatable integrally with the opening member 22 ₁ . That is, the opening member 22 ₁₁ opening 22 ₁₁ c interval, narrow portion and a prism deflecting portion 23 of the inclined surface 23b ₁₁ thicker portion and a gap wide portion of the opening 22 ₁₁ c of the opening member 22 ₁₁ of the prism deflection unit 23 of the The thin portions of the inclined surface 23b ₁₁ can rotate in a corresponding state.

  By adopting such a configuration of the prism deflecting unit 23, the two optical paths divided by the pupil dividing unit 22 can be shifted so that the images do not overlap when the rear group forms an image. It becomes possible to form an image with the light beams in parallel. Furthermore, since the telecentricity on the image plane side is improved by separating the light beams from each other by the prism deflecting unit 3, it is preferable when using an imaging device having a sensitive incident angle characteristic.

Further, by arranging the prism deflecting unit 23 adjacent to the pupil dividing unit 22 on the optical path, the light beam is narrowed down, and the stereoscopic imaging optical system can be downsized. In another example of the third embodiment, from the object side on the optical axis, the slit member 22 _{2 of} the pupil division unit 22, the opening member 22 ₁₁ of the pupil division unit 22, the first surface 23a of the prism deflection unit 23, and the prism deflection. It arrange | positions so that it may rank with the 2nd surface 23b of the part 23 in order. Then, constituting an opening member 22 ₁₁ and the prism deflection unit 23 of the pupil division unit 22 so that it can rotate integrally. The prism deflecting unit 3 may be arranged on either the object side or the image plane side of the pupil dividing unit 2 on the optical path.

  FIG. 36 is a diagram illustrating a stereoscopic near point state and a stereoscopic far point state of the stereoscopic imaging optical system according to the third embodiment. FIG. 36A is a diagram showing a stereoscopic near point state of the stereoscopic imaging optical system of the third embodiment, and FIG. 36B is a stereoscopic far point state of the stereoscopic imaging optical system of the third embodiment. FIG.

To a far point state stereoscopic shown in FIG. 36 (b) from stereoscopic near point state shown in FIG. 36 (a) is in the opening member 22 ₁₁ and the prism deflection unit 23 only rotates with respect to the optical axis Lc Good.

  37 and 38 are aberration diagrams of the stereoscopic imaging optical system according to the third embodiment in the stereoscopic vision near point state. Further, FIGS. 39 and 40 are aberration diagrams of the stereoscopic imaging optical system of the third embodiment in the stereoscopic vision far point state.

  FIG. 41 is a cross-sectional view of the stereoscopic imaging optical system of the fourth embodiment.

  The stereoscopic imaging optical system 1 according to the fourth embodiment includes a front lens group Gf having a single optical axis Lc, a rear lens group Gr arranged coaxially with the front lens group Gf and having a single optical axis Lc, It is arranged between the front lens group Gf and the rear lens group Gr, and can switch to a stereoscopic near point state that forms at least two apertures and a stereoscopic far point state in which the distance between the apertures is wider than the stereoscopic near point state. A pupil dividing unit 22 and a prism deflecting unit 33 arranged to correspond to the pupil dividing unit 22 to deflect a light beam are provided.

The front lens group Gf includes, in order from the object side to the image side, a plano-concave negative lens L _f1 having a flat surface facing the object side, a positive meniscus lens L _f2 having a convex surface facing the image surface side, and a convex surface facing the image surface side. A negative meniscus lens L _f3 that is directed, a positive meniscus lens L _f4 that has a convex surface facing the object side, and a positive meniscus lens L _f5 that has a convex surface facing the object side.

  The front lens group Gf is effective in increasing the angle of view by disposing at least two lenses having negative refractive power on the object side, thereby reducing the focal length of the front lens group Gf. Further, by making the object side surface of the lens having a negative refractive power on the object side flat, it is possible to reduce adhesion of dirt and the like.

The rear lens group Gr includes, in order from the object side to the image side, a cemented lens SU _{r1 of} a positive meniscus lens L _r1 having a convex surface facing the image surface side and a negative meniscus lens L _r2 having a convex surface facing the image surface side, and the object side A positive meniscus lens L _r3 having a convex surface facing the surface, a positive meniscus lens L _r4 having a convex surface facing the object side, and a negative meniscus lens L _r5 having a convex surface facing the object side.

  In front of the image plane I, a filter F and a cover glass C are arranged.

  The pupil division unit 22 may have the same configuration as that of the third embodiment shown in FIGS.

  FIG. 42 is a diagram illustrating an example of a deflection unit of the stereoscopic imaging optical system according to the fourth embodiment.

As shown in FIG. 42, the prism deflecting unit 33 has a first surface 33a having a flat surface and a second surface 33b opposite to the first surface 33a. The second surface 33b has a first convex portion 33b ₁ at a position corresponding to the first opening 22 ₁ a of the opening member 22 ₁ shown in FIG. 27, and corresponds to the second opening 22 ₁ b. The second convex portion 33b ₂ is provided at the position to be operated. The first convex portion 33b ₁ and the second convex portion 33b ₂ are thickest in the optical axis direction from the second surface 23b on the side close to the optical axis Lc, and become thinner as the distance from the optical axis Lc increases. It is formed so as to be inclined.

The prism deflection unit 33 is configured to be rotatable opening member 22 ₁ integral. That is, the second convex opening member 22 ₁ of the first opening 22 ₁ a and the first protrusion 33b ₁ and the opening member 22 ₁ of the second opening 22 ₁ b and the prism deflection unit 33 of the prism deflection unit 33 The portions 33b ₂ can be rotated in a corresponding state.

  By configuring the prism deflecting unit 33 in this way, the two optical paths divided by the pupil dividing unit 22 can be shifted so that the images do not overlap when the rear group forms an image. It becomes possible to form an image with the light beams in parallel. Furthermore, since the telecentricity on the image plane side is improved by separating the light beams from each other by the prism deflecting unit 3, it is preferable when using an imaging device having a sensitive incident angle characteristic.

Further, by arranging the prism deflecting unit 33 adjacent to the pupil dividing unit 22 on the optical path, the light flux is narrowed down, and the stereoscopic imaging optical system can be downsized. In the fourth embodiment, the slit member 22 _{2 of} the pupil dividing unit 22, the opening member 22 ₁ of the pupil dividing unit 22, the first surface 33 a of the prism deflecting unit 33, and the first of the prism deflecting unit 33 from the object side on the optical axis. The two surfaces 33b are arranged in order. Then, constituting an opening member 22 ₁ and the prism deflection unit 33 of the pupil division unit 22 so that it can rotate integrally. The prism deflecting unit 3 may be arranged on either the object side or the image plane side of the pupil dividing unit 2 on the optical path.

  FIG. 43 is a diagram illustrating a stereoscopic near point state and a stereoscopic far point state of the stereoscopic imaging optical system according to the fourth embodiment. FIG. 43A is a diagram showing a stereoscopic near point state of the stereoscopic imaging optical system of the fourth embodiment, and FIG. 43B is a stereoscopic far point state of the stereoscopic imaging optical system of the fourth embodiment. FIG.

To a far point state stereoscopic shown in FIG. 44 (b) from stereoscopic near point state shown in FIG. 43 (a), by the opening member 22 ₁ and the prism deflection unit 33 only rotates with respect to the optical axis Lc Good.

As shown in FIG. 43, the prism deflection unit 33 of the stereoscopic imaging optical system according to the fourth embodiment has the first convex portion 33b ₁ and the second convex portion 33b ₂ in the optical axis direction from the second surface 23b. Of the first opening 22 ₁ a and the first convex portion 33 b ₁ or the second convex portion 2 ₁ a and the second convex portion 33 b ₁ . the light beam which has passed through the opening 22 ₁ b and the second protrusions 33b ₂ is deflected so as to intersect with the rear lens group Gr.

  Therefore, the diameter of the light beam in the rear lens group Gr can be reduced, and the rear lens group Gr can be reduced in size. Note that when the optical paths cross each other, the left and right images are interchanged, so it is preferable to electronically interchange the left and right images.

  44 and 45 are aberration diagrams of the stereoscopic imaging optical system according to the fourth embodiment in the state of a stereoscopic near point. FIGS. 46 and 47 are aberration diagrams of the stereoscopic imaging optical system according to the fourth embodiment in the stereoscopic viewing point state.

  The configuration parameters of Embodiments 1 to 4 are shown below. Eccentricity is given with the optical axis Lc as the Z-axis, and each surface is given in the X-axis direction corresponding to the left-right direction, and the inclination β is the direction of rotation around the Y-axis. After the eccentricity, it returns to the origin before the eccentricity and proceeds in the Z-axis direction given by the surface interval to be the origin of the next surface. The refractive index and the Abbe number are shown for the d-line (wavelength 587.56 nm). Since the lens data is symmetrical, only one side is shown. The unit of length is mm.

Embodiment 1
Specification object point Far point Near point Normal observation object distance 30.00 15.00 30.00
NA 0.017 0.025 0.084
Focal length 10.04 9.85 10.04
Magnification 0.246 0.381 0.246
Angle of convergence (one side deg) 3.468 3.442 0.000
Image height 7.2 × 6.4 7.2 × 12.8 (vertical × horizontal)

Surface data surface number Curvature radius Surface spacing Eccentricity Refractive index Abbe number Object surface ∞ 30.00
1 ∞ 2.00 1.8830 40.7
2 14.37 10.46
3 -11.40 5.00 1.8830 40.7
4 -14.55 1.00
5 44.01 8.00 1.8830 40.7
6 -53.98 0.20
7 55.87 17.23 1.8830 40.7
8 ∞ 2.00
9 Diaphragm surface 2.00 Eccentricity (1) 1.8830 40.7
10 ∞ 2.00 Eccentricity (2)
11 -16.93 2.00 1.6727 32.1
12 13.91 10.00 1.7440 44.8
13 -25.38 0.20
14 41.85 10.00 1.6031 60.6
15 -13.71 2.00 1.9229 18.9
16 -57.29 0.10
17 17.90 10.05 1.9229 18.9
18 41.88 5.01
19 ∞ 0.20 1.5229 59.9
20 ∞ 0.10
21 ∞ 0.45 1.5163 64.1
Image plane ∞ Eccentricity (3)

Eccentric [1]
Far point X 4.13 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Near point X 2.66 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Normal observation X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

Eccentric [2]
Far point X 4.13 Y 0.00 Z 0.00
α 0.00 β 12.12 γ 0.00
Near point X 2.67 Y 0.00 Z 0.00
α 0.00 β 11.44 γ 0.00
Normal observation X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

Eccentric [3]
Stereoscopic observation X 3.20 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Normal observation X 3.20 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

Embodiment 2
Specification point Stereoscopic observation Normal observation object distance 30.00
NA 0.029 0.029
Focal length 10.916 10.916
Magnification 0.246 0.246
Angle of convergence (one side deg) 3.468 0.000
Image height 7.2 × 6.4 7.2 × 12.8 (vertical × horizontal)

Surface data surface number Curvature radius Surface spacing Eccentricity Refractive index Abbe number Object surface ∞ 30.00
1 ∞ 2.00 1.8830 40.7
2 14.37 10.46
3 -11.40 5.00 1.8830 40.7
4 -14.55 1.00
5 44.01 8.00 1.8830 40.7
6 -53.98 0.20
7 55.87 17.23 1.8830 40.7
8 ∞ 2.00
9 Diaphragm surface 2.00 Eccentricity (1) 1.8830 40.7
10 ∞ 2.00 Eccentricity (2)
11 -16.93 2.00 1.6727 32.1
12 13.91 10.00 1.7440 44.8
13 -25.38 0.20
14 41.85 10.00 1.6031 60.6
15 -13.71 2.00 1.9229 18.9
16 -57.29 0.10
17 17.90 10.05 1.9229 18.9
18 41.88 5.01
19 ∞ 0.20 1.5229 59.9
20 ∞ 0.10
21 ∞ 0.45 1.5163 64.1
Image plane ∞ Eccentricity (3)

Eccentric [1]
Stereoscopic observation X 4.13 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Normal observation X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

Eccentric [2]
Stereoscopic observation X 4.13 Y 0.00 Z 0.00
α 0.00 β 12.12 γ 0.00
Normal observation X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

Eccentric [3]
Stereoscopic observation X 3.20 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Normal observation X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

Embodiment 3
Specification point Far point Near point Object distance 16.00 8.00
NA 0.022 0.037
Focal length 4.109 4.409
Magnification 0.210 0.355
Angle of convergence (one side deg) 3.458 3.451
Image height 3.60 x 3.20 (vertical x horizontal)

Surface data Surface number Curvature radius Surface spacing Eccentric Refractive index Abbe number Object surface ∞ 16.00
1 ∞ 1.00 1.8830 40.7
2 5.39 2.75
3 -6.93 2.00 1.8830 40.7
4 -5.68 0.62
5 -4.46 2.00 1.8830 40.7
6 -5.55 0.90
7 9.75 2.00 1.5688 56.3
8 22.47 1.00
9 8.71 4.00 1.8830 40.7
10 9.17 0.80
11 Diaphragm surface 2.00 Eccentricity (1) 1.8830 40.7
12 ∞ 1.00 Eccentricity (2)
13 -32.29 4.00 1.5688 56.3
14 -3.76 2.00 1.9229 18.9
15 -6.63 0.40
16 11.41 2.00 1.5688 56.3
17 95.49 0.40
18 6.49 3.00 1.5688 56.3
19 6.79 0.87
20 11.14 1.00 1.8830 40.7
21 7.92 0.97
22 ∞ 0.20 1.5229 59.9
23 ∞ 0.10
24 ∞ 0.45 1.5163 64.1
Image plane ∞ 0.00 Eccentricity (3)

Eccentric [1]
Far point X 2.13 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Near point X 1.29 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

Eccentric [2]
Far point X 2.13 Y 0.00 Z 0.00
α 0.00 β 13.54 γ 0.00
Near point X 1.29 Y 0.00 Z 0.00
α 0.00 β 13.54 γ 0.00

Eccentric [3]
X 1.60 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

Embodiment 4
Specification point Far point Near point Object distance 16.00 8.00
NA 0.020 0.034
Focal length 4.355 4.355
Magnification 0.219 0.367
Angle of convergence (one side deg) 3.453 3.440
Image height 3.60 x 3.20 (vertical x horizontal)

Surface data Surface number Curvature radius Surface spacing Eccentric Refractive index Abbe number Object surface ∞ 16.00
1 ∞ 1.00 1.8830 40.7
2 4.24 1.32
3 -9.67 1.50 1.8830 40.7
4 -6.30 0.52
5 -4.18 1.50 1.8830 40.7
6 -5.83 1.33
7 30.11 3.00 1.5688 56.3
8 -8.29 1.00
9 21.06 4.00 1.8830 40.7
10 18.23 0.80
11 Diaphragm surface 2.00 Eccentricity (1) 1.8830 40.7
12 ∞ 1.00 Eccentricity (2)
13 59.66 1.50 1.9229 18.9
14 5.40 3.00 1.5688 56.3
15 -22.20 0.40
16 7.92 1.50 1.5688 56.3
17 394.99 0.40
18 5.71 2.97 1.5688 56.3
19 4.10 2.45
20 7.73 2.84 1.8830 40.7
21 52.78 1.80
22 ∞ 0.20 1.5229 59.9
23 ∞ 0.10
24 ∞ 0.45 1.5163 64.1
Image plane ∞ 0.00 Eccentricity (3)

Eccentric [1]
Far point X 2.40 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Near point X 1.42 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

Eccentric [2]
Far point X 2.40 Y 0.00 Z 0.00
α 0.00 β -11.62 γ 0.00
Near point X 1.42 Y 0.00 Z 0.00
α 0.00 β -11.77 γ 0.00

Eccentric [3]
X -1.60 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00

  In the present embodiment, it is preferable to electronically correct chromatic aberration generated in the prism deflection unit. In the wedge-shaped prism, chromatic aberration in which RGB is simply shifted laterally occurs, so that correction can be made by electronically shifting the RGB signal laterally.

  Although various embodiments of the present invention have been described above, the present invention is not limited to these embodiments, and embodiments configured by appropriately combining the configurations of the respective embodiments also fall within the scope of the present invention. Is.

DESCRIPTION OF SYMBOLS 1 ... Stereo imaging optical system Gf ... Front lens group Gr ... Rear lens group 2, 12, 22 ... Pupil division part 3, 13, 23, 33 ... Prism deflection part (deflection part)
I ... Image plane

Claims (5)

A front lens group having a single optical axis;
A rear lens group having a single optical axis arranged coaxially with the front lens group;
A pupil division unit arranged between the front lens group and the rear lens group and capable of dividing a light beam;
A deflecting unit that is disposed between the front lens group and the rear lens group to deflect a light beam;
With
The pupil division unit can be switched between a stereoscopic near-point state in which the light beam is divided by at least two openings and a stereoscopic far-point state in which the light is divided by at least two openings that are wider than the stereoscopic near-point state. A stereoscopic imaging optical system characterized by the above. The stereoscopic imaging optical system according to claim 1, wherein the deflecting unit is disposed adjacent to the rear lens group side of the pupil dividing unit. The stereoscopic imaging optical system according to claim 2, wherein the deflecting unit deflects the light beams divided by the pupil dividing unit so as to intersect in the rear lens group. The stereoscopic imaging optical system according to any one of claims 1 to 3, wherein the pupil division unit can be switched to a monocular viewing state in which a light beam passes through one opening. The stereoscopic imaging optical system according to any one of claims 1 to 4,
An imaging device having an imaging surface disposed on the image side of the stereoscopic imaging optical system;
An endoscope characterized by comprising:

Images