JP2005321437A - Optical system and electronic equipment using it - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a small-sized, thin and inexpensive optical system, and also to provide electronic equipment using it. <P>SOLUTION: The optical system includes: a diaphragm 2; at least one face object side reflection face 12 arranged at an object side therefrom and inclined from an optical axis; at least one-face image side reflection faces 22 and 23; and at least an imaging element 3. When a plane regulated by a main light beam on an incident side axis to each reflection face and a main light beam on a reflection side axis on the reflection faces inclined from all optical axes in the optical system is made a reference face of each reflection face, the optical system has an aspheric shape in which the reference face of at least the one face object side reflection face 12 and the reference face of at least the one-face image side reflection faces 22 and 23 are intersected at an arbitrary angle and at least the one face object side reflection face 12 and at least one-face image side reflection faces 22 and 23 are rotationally asymmetrical. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an optical system and an electronic apparatus using the same, and more particularly to a compact optical system and an electronic apparatus using such an optical system. Examples of the electronic apparatus include a digital camera, a video camera, a digital video unit, a personal computer, a mobile computer, a mobile phone, and an information portable terminal.

Patent Document 1, Patent Document 2, Patent Document 3, Patent Document 4, Patent Document 5, and the like are known as components in which an imaging optical system is configured by a free-form curved prism.
JP-A-11-64734 JP 2002-196243 A JP-A-8-292371 JP 2001-42220 A JP 2001-330795 A

  An axial ray is a ray that passes from the center of the object, passes through the center of the aperture, and reaches the center of the image. In addition, a reference plane is set for a reflective surface that is arranged to be inclined with respect to the optical axis. This reference plane is a plane defined by the axial principal ray incident on the reflecting surface and the reflected axial principal ray. This reference surface exists for each reflecting surface.

  Here, in Patent Documents 1 and 2, all the reference surfaces are within one surface. For this reason, the optical system cannot be said to be thin. On the other hand, in Patent Document 3 and Patent Document 4, thinning is realized by reflecting light three-dimensionally. However, it is the same that all reference planes are in one plane. In addition, since the optical system relays an image, the number of reflections is large. Therefore, the volume cannot be reduced so much. In addition, since the number of reflections is large, surface accuracy errors, eccentricity accuracy errors, and the like are accumulated. As a result, the accuracy required for each reflecting surface becomes strict, leading to an increase in cost.

  Patent Document 5 also reflects light three-dimensionally. However, since the optical system relays an image, the number of reflections is large. Therefore, it cannot be said that it is small and thin. In addition, since the number of reflections is large, surface accuracy errors, eccentricity accuracy errors, and the like are accumulated. As a result, the accuracy required for each reflecting surface becomes strict, leading to an increase in cost.

  The present invention has been made in view of such problems of the prior art, and an object of the present invention is to provide a small, thin and low-cost optical system and an electronic apparatus using the same.

A first optical system of the present invention that achieves the above object includes a stop, at least one object-side reflecting surface that is disposed on the object side of the stop and is inclined from the optical axis, and light disposed on the image side of the stop. In a positive power optical system having at least one image-side reflecting surface inclined from an axis and an image sensor,
Rays from the center of the object through the center of the aperture to the center of the image are axial principal rays, and for the reflective surfaces tilted from all the optical axes in the optical system, the incident side axial principal rays and the reflective side axes for each reflective surface When the plane defined by the upper principal ray is the reference surface of each reflecting surface,
At least one reference surface of the object side reflection surface and at least one reference surface of the image side reflection surface intersect at an arbitrary angle,
At least one object-side reflecting surface and at least one image-side reflecting surface have a rotationally asymmetric aspherical shape.

  Hereinafter, the reason and effect | action which take the said structure in a 1st optical system are demonstrated.

  The first optical system is a positive power imaging optical system that forms an image of a predetermined object on the imaging device by the optical system. In the first optical system, at least one reflecting surface is disposed before and after the aperture stop, respectively. The reflecting surface has a rotationally asymmetric aspherical shape.

  At that time, the reference surface of at least one object-side reflecting surface and the reference surface of at least one image-side reflecting surface do not exist in the same plane, and are reflected so as to intersect each other at an arbitrary angle. The surface is arranged. Such an arrangement will be referred to herein as three-dimensional eccentricity. The plane defined by the axial principal ray from the object center to the image center through the stop center and the axial principal ray incident on the reflecting surface and the axial principal ray reflected by the reflecting surface is the reference plane. It is as described above.

  In addition, in a reflection optical system in which reflection surfaces are arranged before and after the stop, the optical system can be reduced in size by adopting such a three-dimensional eccentric arrangement. Furthermore, since the degree of freedom in the shape of the optical system is increased, for example, it is possible to flexibly meet demands such as to particularly suppress the thickness direction. Note that the reflecting surface has a rotationally asymmetric aspherical shape.

  This point will be described with reference to FIG. FIG. 1 is a perspective view schematically showing a reflecting surface R that is inclined with respect to one optical axis (axial principal ray) and is a rotationally asymmetric aspherical surface. Here, a plane including the central ray of the incident ray (axial principal ray) and the central ray of the reflected ray is taken as a reference plane. The direction in which the reference surface and the aspherical reflecting surface R intersect is the meridian direction. In addition, a direction perpendicular to the reference plane at the point where the axial principal ray is incident is defined as a spherical missing direction. Here, in FIG. 1, the aspherical reflecting surface R is inclined (eccentric) with respect to the axial principal ray. For this reason, the focal length in the sphere missing direction becomes longer (power becomes weaker) than when there is no eccentricity. Conversely, the focal length in the meridian direction becomes shorter (power becomes stronger) than when there is no eccentricity. For this reason, if the convergence or diverging action is to be made the same as the focal length when there is no eccentricity, the focal length must be shortened in the sphere missing direction. This is not preferable for aberration correction. In addition, it is not preferable because the manufacturing difficulty of the aspherical reflecting surface R is increased and the cost is increased.

  Therefore, in the first optical system, the reference surface of the object side reflecting surface (hereinafter referred to as the first reflecting surface) and the reference surface of the image side reflecting surface (hereinafter referred to as the second reflecting surface) intersect each other at an arbitrary angle. As shown, each surface is arranged. As this arrangement, for example, there is an arrangement in which both reference planes are orthogonal. By doing in this way, the spherical missing direction on the first reflecting surface becomes the meridian direction on the second reflecting surface. Therefore, even if the power in the sphere missing direction is insufficient on the first reflecting surface, the shortage can be compensated for by the second reflecting surface. That is, in order to obtain a predetermined focal length, it is not necessary to forcibly reduce the radius of curvature in the sphere missing direction on the first reflecting surface. On the other hand, in the meridional direction on the second reflecting surface, a stronger power can be obtained simply by tilting the surface. Therefore, since it is sufficient to adjust and correct a relatively large radius of curvature, the occurrence of aberrations can be reduced. As a result, good aberration correction can be realized at low cost.

  As described above, when the reference surface of the first reflecting surface and the reference surface of the second reflecting surface are arranged so as to intersect at an arbitrary angle, each reflecting surface is necessarily arranged three-dimensionally eccentric. In this case, rotationally asymmetrical aberrations (hereinafter simply referred to as rotationally asymmetrical aberrations) due to three-dimensional decentration occur, but this rotationally asymmetrical aberration cannot be corrected only with a rotationally symmetric optical system. It is. Here, the best surface shape for correcting rotationally asymmetrical aberration is a rotationally asymmetrical aspherical surface. Therefore, in the first optical system, it is desirable that at least one object-side reflecting surface and at least one image-side reflecting surface have such a rotationally asymmetric aspheric shape.

  Here, as a surface having a rotationally asymmetric aspherical shape, a free-form surface can be used as a representative surface. The free-form surface is defined by the following equation. The Z axis of this defining formula is the axis of the free-form surface.

₆₆
Z = cr ² / [1 + √ {1− (1 + k) c ² r ² }] + ΣC _j X ^m Y ^{n
j = 2}
... (a)
Here, the first term of the equation (a) is a spherical term, and the second term is a free-form surface term.

In the spherical term,
c: curvature of vertex k: conic constant (conical constant)
r = √ (X ² + Y ² )
It is.

The free-form surface term is
₆₆
ΣC _j X ^m Y ^{n
j = 2}
= C ₂ X + C ₃ Y
+ C ₄ X ² + C ₅ XY + C ₆ Y ²
+ C ₇ X ³ + C ₈ X ² Y + C ₉ XY ² + C ₁₀ Y ³
+ C ₁₁ X ⁴ + C ₁₂ X ³ Y + C ₁₃ X ² Y ² + C ₁₄ XY ³ + C ₁₅ Y ⁴
+ C ₁₆ X ⁵ + C ₁₇ X ⁴ Y + C ₁₈ X ³ Y ² + C ₁₉ X ² Y ³ + C ₂₀ XY ⁴
+ C ₂₁ Y ⁵
+ C ₂₂ X ⁶ + C ₂₃ X ⁵ Y + C ₂₄ X ⁴ Y ² + C ₂₅ X ³ Y ³ + C ₂₆ X ² Y ⁴
+ C ₂₇ XY ⁵ + C ₂₈ Y ⁶
+ C ₂₉ X ⁷ + C ₃₀ X ⁶ Y + C ₃₁ X ⁵ Y ² + C ₃₂ X ⁴ Y ³ + C ₃₃ X ³ Y ⁴
+ C ₃₄ X ² Y ⁵ + C ₃₅ XY ⁶ + C ₃₆ Y ⁷
・ ・ ・ ・ ・ ・
However, C _j (j is an integer of 2 or more) is a coefficient.

  In general, the free-form surface does not have a symmetric surface in both the XZ plane and the YZ plane, but by setting all odd-order terms of X to 0, the plane of symmetry is parallel to the YZ plane. Is a free-form surface with only one. Further, by setting all odd-numbered terms of Y to 0, a free-form surface having only one symmetry plane parallel to the XZ plane is obtained.

  Further, another defining formula of the free-form surface which is a surface of the rotationally asymmetric curved surface can be defined by a Zernike polynomial. The shape of this surface is defined by the following formula (b). The Z axis of the defining formula (b) is the axis of the Zernike polynomial. The definition of the rotationally asymmetric surface is defined by polar coordinates of the height of the Z axis with respect to the XY plane, R is the distance from the Z axis in the XY plane, A is the azimuth around the Z axis, and the X axis It is expressed by the rotation angle measured from.

x = R × cos (A)
y = R × sin (A)
Z = D ₂
+ D ₃ Rcos (A) + D ₄ Rsin (A)
+ D ₅ R ² cos (2A) + D ₆ (R ² −1) + D ₇ R ² sin (2A)
+ D ₈ R ³ cos (3A) + D ₉ (3R ³ −2R) cos (A)
+ D ₁₀ (3R ³ -2R) sin (A) + D ₁₁ R ³ sin (3A)
+ D ₁₂ Recos (4A) + D ₁₃ (4R ⁴ -3R ² ) cos (2A)
+ D ₁₄ (6R ⁴ -6R ² +1) + D ₁₅ (4R ⁴ -3R ² ) sin (2A)
^{_{+ D 16 R 4 sin (4A}} ) + D 17 R 5 cos (5A) + D 18 (5R 5 -4R 3) cos (3A)
+ D ₁₉ (10R ⁵ -12R ³ + 3R) cos (A)
+ D ₂₀ (10R ⁵ -12R ³ + 3R) sin (A)
+ D ₂₁ (5R ⁵ -4R ³ ) sin (3A) + D ₂₂ R ⁵ sin (5A)
+ D ₂₃ Rocos (6A) + D ₂₄ (6R ⁶ -5R ⁴ ) cos (4A)
+ D ₂₅ (15R ⁶ -20R ⁴ + 6R ² ) cos (2A)
+ D ₂₆ (20R ⁶ -30R ⁴ + 12R ² -1)
+ D ₂₇ (15R ⁶ -20R ⁴ + 6R ² ) sin (2A)
+ D ₂₈ (6R ⁶ -5R ⁴ ) sin (4A) + D ₂₉ Rosin (6A)
... (b)
However, _Dm (m is an integer greater than or equal to 2) is a coefficient. In order to design an optical system symmetrical in the X-axis direction, D ₄ , D ₅ , D ₆ , D ₁₀ , D ₁₁ , D ₁₂ , D ₁₃ , D ₁₄ , D ₂₀ , D ₂₁ , D ₂₂ . Use.

  The above definition formula is shown for illustration of a rotationally asymmetric curved surface, and it goes without saying that the same effect can be obtained for any other definition formula.

  In addition, the following definition formula (c) is mention | raise | lifted as an example of the other definition formula of a free-form surface.

Z = ΣΣC _nm XY
As an example, when k = 7 (seventh order term) is considered, when expanded, it can be expressed by the following expression.

Z = C ₂
+ C ₃ Y + C ₄ | X |
+ C ₅ Y ² + C ₆ Y | X | + C ₇ X ²
+ C ₈ Y ³ + C ₉ Y ² | X | + C ₁₀ YX ² + C ₁₁ | X ³ |
+ C ₁₂ Y ⁴ + C ₁₃ Y ³ | X | + C ₁₄ Y ² X ² + C ₁₅ Y | X ³ | + C ₁₆ X ⁴
+ C ₁₇ Y ⁵ + C ₁₈ Y ⁴ | X | + C ₁₉ Y ³ X ² + C ₂₀ Y ² | X ³ |
+ C ₂₁ YX ⁴ + C ₂₂ | X ⁵ |
+ C ₂₃ Y ⁶ + C ₂₄ Y ⁵ | X | + C ₂₅ Y ⁴ X ² + C ₂₆ Y ³ | X ³ |
+ C ₂₇ Y ² X ⁴ + C ₂₈ Y | X ⁵ | + C ₂₉ X ⁶
+ C ₃₀ Y ⁷ + C ₃₁ Y ⁶ | X | + C ₃₂ Y ⁵ X ² + C ₃₃ Y ⁴ | X ³ |
+ C ₃₄ Y ³ X ⁴ + C ₃₅ Y ² | X ⁵ | + C ₃₆ YX ⁶ + C ₃₇ | X ⁷ |
... (c)
An anamorphic surface or a toric surface can be used as the rotationally asymmetric surface.

  In the first optical system, reflecting surfaces are arranged before and after the aperture stop. For this reason, the first optical system has a diaphragm symmetrical configuration. A diaphragm symmetric configuration is preferable in terms of aberration correction. In particular, when a rotationally asymmetric aspherical surface is used for the reflecting surface and the reflecting surface is arranged as described above with the three-dimensional eccentricity, it is preferable to arrange these reflecting surfaces with a stop interposed therebetween. At this time, in order to prevent interference between the reflecting surface and the stop, it is necessary to dispose the first reflecting surface and the second reflecting surface away from the stop. Since the first reflecting surface is arranged away from the stop, the first reflecting surface is preferably used for coma aberration and distortion aberration. However, as described above, it is difficult to reduce the radius of curvature in the sphere missing direction on the first reflecting surface in terms of aberration fluctuation (deterioration). On the other hand, if the radius of curvature of the first reflecting surface is relatively large in order to avoid aberration fluctuation, desired aberration correction cannot be performed.

  However, since the second reflecting surface is also arranged away from the stop, by correcting aberrations in the meridional direction of the second reflecting surface, aberrations are corrected in the spherical direction of the first reflecting surface. The effect equivalent to is obtained. In this way, by using a rotationally asymmetric aspherical surface, a three-dimensional eccentric arrangement, and a diaphragm symmetric configuration, it is possible to realize good aberration correction at low cost. Similar effects can be obtained by using a relay optical system. However, this is not preferable because the total length of the optical system becomes long.

  In the first optical system, the second optical system has all rotationally asymmetric aspherical shapes of the reflecting surfaces when the intersecting line between the reflecting surface and the reference surface is the intersecting line of the reflecting surfaces. The reflecting surface satisfies the following conditional expression.

−5 <Rry / Rrx <5 (1)
Here, Rry is the radius of curvature of each reflecting surface in the direction of intersection, and Rrx is the radius of curvature of each reflecting surface in the direction perpendicular to the direction of intersection.

  Hereinafter, the reason and effect | action which take the said structure in a 2nd optical system are demonstrated.

  When the rotationally asymmetric aspherical reflecting surface is tilted with respect to the optical axis, the curvature radius in the sphere missing direction is larger than the meridian direction as described above when trying to obtain the same convergence / divergence effect as in the meridian direction. Must be reduced. This is not preferable in terms of aberration correction. In addition, it is not preferable from the viewpoint of increasing the manufacturing difficulty and increasing the cost. Therefore, by performing three-dimensional eccentricity and satisfying conditional expression (1), the radius of curvature of the first reflecting surface in the spherical missing direction can be increased. As a result, better aberration correction can be achieved. In addition, since the manufacturing difficulty level is lowered, the cost can be reduced.

  If the upper limit of 5 of conditional expression (1) is exceeded and Rrx becomes small, it is not preferable for aberration correction. In addition, it is not preferable because the manufacturing difficulty increases and the cost also increases. There is no point in satisfying conditional expression (1) without performing three-dimensional eccentricity. This is because it is necessary to obtain the power in the sphere missing direction on a surface other than the first reflecting surface. In this case, the curvature radius in the direction of the sphere must be reduced on other reflecting surfaces and refracting surfaces. In this case, the power in the sphere missing direction is further increased, which is not preferable for aberration correction. In addition, it is not preferable because the manufacturing difficulty increases and the cost also increases. If Rrx becomes smaller than −5, which is the lower limit of conditional expression (1), it is not preferable in terms of aberration correction. In addition, it is not preferable because the manufacturing difficulty level increases. In addition, since the reflecting surface has a bowl shape, the manufacturing difficulty level further increases. Therefore, the cost increases, which is not preferable.

  Furthermore, it is preferable that the following conditional expression (1-2) is satisfied. By satisfying this condition, it is possible to further reduce the manufacturing difficulty and reduce the cost.

-2 <Rry / Rrx <2 (1-2)
The upper and lower limits of conditional expression (1-2) have the same meaning as conditional expression (1).

  Furthermore, it is preferable that the following conditional expression (1-3) is satisfied. By satisfying this condition, it is possible to further reduce the manufacturing difficulty and reduce the cost.

-0.5 <Rry / Rrx <0.5 (1-3)
The upper and lower limits of conditional expression (1-3) have the same meaning as conditional expression (1).

  In the first and second optical systems, the third optical system rotates the reflecting surface arranged closest to the object side when the intersecting line between the reflecting surface and the reference surface is the intersecting line of each reflecting surface. A reflecting surface having an asymmetric aspherical shape and arranged closest to the object side satisfies the following conditional expression.

−0.5 <1 / (Rr1x · P1y) <0.5 (2)
Here, Rr1x is the radius of curvature in the direction perpendicular to the intersecting direction of the reflecting surface disposed on the most object side, and P1y is the power of the entire system in the intersecting direction of the reflecting surface disposed on the most object side.

  Hereinafter, the reason and effect | action which take the said structure in a 3rd optical system are demonstrated.

  As described above, in the state where the rotationally asymmetric aspherical reflecting surface is inclined with respect to the optical axis, when trying to obtain a convergence / divergence effect similar to the meridian direction, as described above, the sphere is smaller than the meridian direction. The radius of curvature in the missing direction becomes smaller. In this case, not only is it not preferable in terms of aberration correction, but it is not preferable because the manufacturing difficulty increases and the cost also increases. Therefore, by performing three-dimensional eccentricity and satisfying conditional expression (2), the radius of curvature of the reflecting surface arranged closest to the object side in the spherical missing direction can be increased. By doing in this way, favorable aberration correction becomes possible. There is no point in satisfying conditional expression (2) without performing three-dimensional eccentricity. This is because it is necessary to obtain power in the direction of the sphere on a surface other than the reflecting surface arranged on the most object side. In this case, the curvature radius in the direction of the sphere must be reduced on other reflecting surfaces and refracting surfaces. This is not preferable from the viewpoint of aberration correction, but is also not preferable from the viewpoint of increasing manufacturing difficulty and cost.

  If Rr1x is smaller than −0.5 which is the lower limit of conditional expression (2), it is not preferable in terms of aberration correction. In addition, it is not preferable because the manufacturing difficulty increases and the cost also increases. Further, in order to obtain a positive power as a whole, if Rr1y (the radius of curvature of the meridional direction of the reflecting surface arranged closest to the object side) is positive, the reflecting surface becomes bowl-shaped. Therefore, the manufacturing difficulty level is further increased. Therefore, the cost increases, which is not preferable. If the upper limit of 0.5 is exceeded and Rr1x becomes small, it is not preferable in terms of aberration correction. In addition, it is not preferable because the manufacturing difficulty increases and the cost also increases.

  Moreover, it is preferable that the following conditional expression (2-2) is satisfied. By satisfying this condition, it is possible to further reduce the manufacturing difficulty and reduce the cost.

0 <1 / (Rr1x · P1y) <0.3 (2-2)
The upper and lower limits of the conditional expression (2-2) have the same meaning as the conditional expression (2).

  Moreover, it is preferable that the following conditional expression (2-3) is satisfied. By satisfying this condition, it is possible to further reduce the manufacturing difficulty and reduce the cost.

0 <1 / (Rr1x · P1y) <0.1 (2-3)
The upper and lower limits of conditional expression (2-3) have the same meaning as conditional expression (2).

  In the first to third optical systems, the fourth optical system has at least one rotationally asymmetric aspherical refracting surface when the intersecting line between the reflecting surface and the reference surface is the intersecting line of each reflecting surface. The most object-side refracting surface among the rotationally asymmetric aspheric refracting surfaces is the object-side refracting surface, and the intersection of the object-side refracting surface and the reference surface of the most object-side reflecting surface is the object-side refracting surface. Assuming intersection lines, the object-side refracting surface satisfies the following conditional expression.

−3 <1 / (Rt1y · P2y) <0 (3)
Where Rt1y is the radius of curvature of the object side refracting surface in the direction of intersection of the object side refracting surfaces, and P2y is the power of the entire system in the direction of intersection of the object side refracting surfaces.

  Hereinafter, the reason and effect | action which take the said structure in a 4th optical system are demonstrated.

  As described above, (1) At least one reflecting surface having a rotationally asymmetric aspherical shape is arranged before and after the stop, (2) a three-dimensional eccentric arrangement, and (3) a sphere missing on the first reflecting surface. With respect to the direction convergence effect, if the second reflecting surface is used, good aberration correction can be realized at low cost. However, since the first reflecting surface and the second reflecting surface are separated from each other, the principal point position and the focal length of the optical system are different between the meridional direction and the spherical direction of the first reflecting surface. As a result, the image is distorted. Therefore, it is preferable to satisfy the conditional expression (3). By satisfying this condition, if the meridional direction of the first reflecting surface can be set to negative power, the rear principal point position of the entire system can be set to the image side in the meridional direction of the first reflecting surface. . As a result, the difference between the principal point position and the focal length of the entire system can be reduced between the meridional direction and the sphere-less direction of the first reflecting surface.

  Below the lower limit of −3 of conditional expression (3), the absolute value of 1 / Rt1y is too large compared to P2y, which is not preferable for aberration correction. In addition, it is not preferable because the manufacturing difficulty increases. If the upper limit of 0 is exceeded, the negative power of the object-side refracting surface in the sphericity direction of the first reflecting surface becomes too small. Therefore, the rear principal point position in that direction cannot be set to the image side. As a result, the difference between the principal point position and the focal length between the meridional direction and the spherical notch direction of the first reflecting surface cannot be reduced, and the influence of image distortion and the like becomes large. Moreover, it is preferable that the following conditional expression (3-2) is satisfied. By satisfying this condition, the difference between the principal point position and the focal length between the meridional direction and the spherical notch direction of the first reflecting surface can be reduced, and the influence of image distortion and the like can be reduced. As a result, good image quality can be obtained at low cost.

−1 <1 / (Rt1y · P2y) <0 (3-2)
The upper and lower limits of conditional expression (3-2) have the same meaning as conditional expression (3).

  Moreover, it is preferable that the following conditional expression (3-3) is satisfied. By satisfying this condition, the difference between the principal point position and the focal length between the meridional direction and the spherical notch direction of the first reflecting surface can be reduced, and the influence of image distortion and the like can be reduced. As a result, good image quality can be obtained at low cost. The meaning of the lower limit of conditional expression (3-3) is the same as that of conditional expression (3). If the upper limit of −0.1 is not exceeded, the influence of image distortion and the like can be further suppressed.

−0.5 / (Rt1y · P2y) <− 0.1 (3-3)
The fifth optical system is characterized in that, in the first to fourth optical systems, all the reflecting surfaces and refracting surfaces have a rotationally asymmetric aspheric shape.

  Hereinafter, the reason and effect | action which take the said structure in a 5th optical system are demonstrated. By making all the reflecting surfaces and refracting surfaces constituting the optical system have a rotationally asymmetric aspherical shape, rotationally asymmetric aberration can be corrected more favorably with a small number of surfaces. As a result, a smaller and thinner optical system can be realized.

  The sixth optical system is the first to fifth optical systems, wherein at least one optical element arranged on the object side from the stop has at least one reflecting surface and at least two refracting surfaces. It is characterized by being.

  In a seventh optical system, in the first to sixth optical systems, at least one optical element arranged on the image side from the stop has at least one reflecting surface and at least two refracting surfaces. It is characterized by being.

  Hereinafter, the reason and effect | action which take the said structure in a 6th, 7th optical system are demonstrated. Since the reflecting surface has higher decentration error sensitivity than the refracting surface, high accuracy is required for assembly adjustment. However, among the reflective optical elements, the relative positional relationship between the surfaces of the prisms is fixed. Therefore, the eccentricity may be controlled as a single prism. Therefore, when a prism is used, an unnecessary assembly accuracy and adjustment man-hours are unnecessary. Further, the prism has an entrance surface and an exit surface, which are refractive surfaces, and a reflection surface. Therefore, the degree of freedom of aberration correction is greater than that of a configuration using a mirror having only a reflecting surface. Particularly, in the prism, most of the desired power is shared by the reflecting surface, and the power of the entrance surface and the exit surface, which are refracting surfaces, can be reduced. By doing in this way, it is possible to make the occurrence of chromatic aberration very small while keeping the degree of freedom of aberration correction large compared to the mirror. Moreover, since the inside of the prism is filled with a transparent body having a refractive index higher than that of air, the optical path length can be made longer than that of air. Therefore, the optical system can be made thinner and smaller than the configuration in which the mirror is arranged in the air.

  The eighth optical system is characterized in that focusing is performed by moving at least one optical element in the sixth and seventh optical systems.

  The ninth optical system is characterized in that focusing is performed by moving at least the image sensor in the first to eighth optical systems.

  The tenth optical system is characterized in that, in the first to ninth optical systems, the stop is disposed substantially perpendicular to the imaging surface of the imaging device.

  The eleventh optical system is characterized in that, in the first to tenth optical systems, the normal vector of the imaging surface of the imaging device is substantially perpendicular to the incident light vector of the optical system.

  In the first to eleventh optical systems, the twelfth optical system is reflected on the intersection line between the object-side reflecting surface disposed closest to the object side and the reference surface of the object-side reflecting surface among the reflecting surfaces. A ray bundle that forms an image in the direction of the substantially short side of the image sensor, and is reflected on the intersection of the image-side reflecting surface disposed closest to the image side and the reference surface of the image-side reflecting surface among the reflecting surfaces. The bundle is arranged so as to form an image in a substantially long side direction of the image sensor.

  Hereinafter, the reason and effect | action which take the said structure in a 12th optical system are demonstrated. With respect to the object-side reflecting surface (hereinafter referred to as the most object-side reflecting surface) arranged closest to the object side, the most object side so that the light flux incident in the meridian direction forms an image in the substantially short side direction of the image sensor. Place a reflective surface. Thereby, the optical path length from the incident surface of an optical system to the most object side reflective surface can be shortened. As a result, the incident light direction of the optical system, that is, the so-called optical system thickness can be reduced. Further, with respect to the image side reflecting surface (hereinafter referred to as the most image side reflecting surface) arranged closest to the image side, the light flux reflected in the meridian direction forms an image in the substantially long side direction of the image sensor. An image side reflecting surface is disposed. In this way, the most object side reflection surface and the most image side reflection surface can be configured so that the reference surface of the most object side reflection surface and the reference surface of the most image side reflection surface intersect substantially perpendicularly. Therefore, the normal vector of the image plane and the incident direction of the light incident on the optical system, that is, the thickness direction of the optical system are substantially perpendicular. Accordingly, it is possible to prevent the optical system from becoming thick due to the influence of the thickness of the image pickup device itself, which is preferable because it is easy to reduce the thickness.

  The thirteenth optical system is characterized in that, in the first to twelfth optical systems, the total number of reflections satisfies the following conditional expression.

2 ≦ R _all ≦ 4 (4)
Here, R _all is the total number of reflections.

  Hereinafter, the reason and effect | action which take the said structure in a 13th optical system are demonstrated. In order to perform three-dimensional eccentricity, a plurality of reflection times are required. However, as the number of reflections increases, (1) the size of the optical system increases, and (2) surface accuracy errors and decentration accuracy errors on each reflecting surface are integrated and transferred. There are many disadvantages such as (3) a large loss of light amount, which is not preferable. (3) If total reflection is used as a countermeasure, the angle of incidence on the reflecting surface increases. For this reason, the problem (2) becomes larger, which is not preferable. By satisfying conditional expression (4), it is possible to achieve both miniaturization and cost reduction, as well as low light loss. If the lower limit of 2 is not reached, it is impossible to eccentrically three-dimensionally while maintaining a small size. Exceeding the upper limit of 4 is not preferable because the number of reflections is too large and the above problem becomes apparent.

  Moreover, it is preferable that the following conditional expression (4-2) is satisfied. By satisfying this condition, it is possible to achieve both cost reduction and low light loss, which is preferable.

2 ≦ R _all ≦ 3 (4-2)
If the upper limit of 3 to the conditional expression (4-2) is exceeded, the optical path length becomes long, which is not suitable for widening the angle of view.

  Moreover, it is preferable that the following conditional expression (4-3) is satisfied. By satisfying this condition, the optical path length can be shortened. Therefore, it is possible to widen the angle of view while maintaining high image quality.

R _all = 2 (4-3)
The fourteenth optical system is characterized in that in the first to thirteenth optical systems, a light shielding member is provided between the reflecting surfaces.

  A fifteenth optical system is characterized in that, in the fourteenth optical system, a light shielding member is formed integrally with the stop.

  Hereinafter, the reason and effect | action which take the said structure in a 14th, 15th optical system are demonstrated. In the decentered optical system having a plurality of reflecting surfaces as described above, there are light rays incident from an angle other than the normal incident angle. Some of these light beams are reflected by a reflecting surface or a refracting surface constituting the optical system and are incident on an imaging surface. The light reaching the imaging surface in this way becomes ghost light or noise light. Therefore, it is preferable to arrange a light shielding member between the reflecting surfaces. In this way, ghost light and noise light can be blocked. In particular, it is desirable to dispose the light shielding member at the opening position where the regular light beam diameter is minimized. In this case, the stop and its light shielding member can be formed integrally.

  The sixteenth optical system includes at least one lens in the first to fifteenth optical systems.

  The seventeenth optical system is characterized in that, in the sixteenth optical system, at least one lens is disposed closer to the image side than all the reflecting surfaces.

  The eighteenth optical system is characterized in that focusing is performed by moving at least one lens in the sixteenth and seventeenth optical systems.

  The nineteenth optical system is characterized in that in the sixteenth optical system, at least one lens is attached closer to the object side than all the reflecting surfaces at the time of photographing.

  The twentieth optical system is characterized in that in the nineteenth optical system, a zooming effect is obtained by attaching a lens.

  Hereinafter, the reason and effect | action which take the said structure in the 16th-20th optical system are demonstrated. In the three-dimensional decentered optical system as described above, it is not essential to use a lens. However, if one or more rotationally symmetric lenses are arranged at any position, this lens can be used for focusing, for wide converters, and for teleconverters. In particular, for focusing, a lens is arranged on the most image side of the optical system so that it can move along the optical axis. For wide converters and teleconverters, the lens is detachable on the most object side of the optical system.

  The twenty-first optical system is characterized in that, in the first to twentieth optical systems, an organic-inorganic composite material is used as an optical material of at least one optical element constituting the optical system.

  Hereinafter, the reason and effect | action which take the said structure in a 21st optical system are demonstrated.

  When an organic-inorganic composite material is used as the optical material of the optical element, various optical properties (refractive index, wavelength dispersion) are exhibited depending on the type and abundance ratio of the organic component and the inorganic component (obtained). ). Therefore, by blending the organic component and the inorganic component in an arbitrary ratio, various optical characteristics can be obtained, and various aberrations can be corrected with a smaller number of sheets, that is, at a low cost and a small size.

  The twenty-second optical system is characterized in that in the twenty-first optical system, the organic-inorganic composite includes zirconia nanoparticles.

  A twenty-third optical system is the twenty-first optical system, wherein the organic-inorganic composite includes nanoparticles of zirconia and alumina.

  A twenty-fourth optical system according to the twenty-first optical system is characterized in that the organic-inorganic composite includes niobium oxide nanoparticles.

  A twenty-fifth optical system is the twenty-first optical system, wherein the organic-inorganic composite includes a hydrolyzate of zirconium alkoxide and alumina nanoparticles.

  In the twenty-second to twenty-fifth optical systems, the reason why the above configuration is adopted and the operation thereof will be described. The nanoparticles of these materials are examples of inorganic components. Then, by dispersing such nanoparticles in an organic component plastic at a predetermined abundance ratio, various optical characteristics (refractive index, wavelength dispersibility) can be expressed.

  The twenty-sixth electronic device includes first to twenty-fifth optical systems and an electronic image pickup element arranged on the image side.

  Hereinafter, the reason and effect | action which take the said structure in the 26th electronic device are demonstrated. The above optical system is a small, thin and low cost optical system. Therefore, if such an optical system is mounted on an electronic device as an imaging optical system, the electronic device can be reduced in size, thickness, and cost. Electronic devices include digital cameras, video cameras, digital video units, personal computers, mobile computers, mobile phones, portable information terminals, electronic endoscopes, and the like.

The twenty-seventh electronic apparatus is characterized in that, in the twenty-sixth electronic apparatus, means for electrically correcting the shape of an image formed by the optical system is provided.
Hereinafter, the reason and effect | action which take the said structure in a 27th electronic device are demonstrated. If the distortion is to be corrected well by the optical system, the number of optical elements increases and the optical system becomes larger. Therefore, the distortion aberration that cannot be corrected by the optical system is electrically corrected. This is preferable because the optical system can be made more compact.

The twenty-eighth electronic device is characterized in that, in the twenty-seventh electronic device, correction uses different parameters for each wavelength region.
The reason and action of the above configuration in the twenty-eighth electronic device will be described below. If it is attempted to satisfactorily correct lateral chromatic aberration with an optical system, the number of optical elements increases and the size of the optical system increases. Therefore, the lateral chromatic aberration that cannot be completely corrected by the optical system is electrically corrected. This is preferable because the optical system can be made more compact.

  The twenty-ninth electronic device is an electronic device including the sixteenth to twentieth optical systems and an image sensor arranged on the image side thereof, and the lens is housed in the electronic device when not in use. It is characterized by.

  Hereinafter, the reason and action of the 29th electronic device having the above configuration will be described. When the lens is detachable, the lens can be stored in the electronic device when not in use. By doing so, the lens can be used at all times when carried, and loss of the lens can be prevented.

  Examples of the optical system (imaging optical system) of the present invention will be described below with reference to the drawings.

  In the configuration parameters of each embodiment, for example, as shown in FIG. 2A in the YZ sectional view and in FIG. 2B in the XY sectional view, the axial principal ray 1 is obtained by forward ray tracing. A light ray that enters perpendicularly to the first surface closest to the object side of the optical system (in FIG. 2, the first surface CG1a of the cover glass CG1), passes through the center of the stop 2 of the optical system, and reaches the center of the image plane 3. Define in. The position at which the first object-side first surface of the optical system (the first surface CG1a of the cover glass CG1 in FIG. 2) and the axial principal ray 1 intersect is the origin of the decentered optical surface of the decentered optical system. . The direction along the axial principal ray 1 is the Z-axis direction, and the direction from the object toward the first surface is the Z-axis positive direction. A plane on which the optical axis (axial principal ray) 1 is bent on the object side from the stop 2 is a YZ plane, and a direction passing through the origin and orthogonal to the YZ plane is an X-axis direction. The direction from the front side to the back side of FIG. 2A is taken as the positive X-axis direction. Furthermore, the X axis, the Z axis, and the axis constituting the right-handed orthogonal coordinate system are defined as the Y axis.

  Examples 1 to 10, which will be described later, include two optical elements having free-form surfaces, and the only symmetrical surface of each rotationally asymmetric free-form surface of the optical element on the object side in each example is a YZ plane. The only symmetrical plane of each rotationally asymmetric free-form surface of the optical element on the image side is a plane passing through the center of the stop 2 and parallel to the XY plane.

  For the decentered surface, the amount of decentering from the origin of the optical system to the top position of the surface (X, Y, and Z axis shift amounts X, Y, Z, respectively) and the center axis of the surface ( For free-form surfaces, inclination angles (α, β, γ (°), respectively) about the X-axis, Y-axis, and Z-axis of the above-described (a) Z-axis) are given. In this case, positive α and β mean counterclockwise rotation with respect to the positive direction of each axis, and positive γ means clockwise rotation with respect to the positive direction of the Z axis. Note that the α, β, and γ rotations of the central axis of the surface are performed by first rotating the central axis of the surface and its XYZ orthogonal coordinate system by α counterclockwise around the X axis, and then rotating the rotation. The center axis of the surface is rotated β counterclockwise around the Y axis of the new coordinate system, and the coordinate system rotated once is also rotated β counterclockwise around the Y axis, and then 2 degrees The center axis of the rotated surface is rotated γ clockwise around the Z axis of the new coordinate system.

  In addition, among the optical functional surfaces (reflecting surfaces, refracting surfaces) constituting the optical system of each embodiment, when a specific surface and a subsequent surface constitute a coaxial optical system, a surface interval is given. In addition, the refractive index and Abbe number of the medium are given in accordance with the conventional method.

  FIG. 2 is a cross-sectional view along the optical axis (axial principal ray) 1 showing the arrangement of the optical system and the optical path according to the first embodiment of the present invention. FIG. 2A is a YZ sectional view taken along the optical axis (axial principal ray) 1 from the center of the object to the center of the stop 2, and the surface after the reflecting surface 23 described later is not on this section. Not shown. FIG. 2B is a cross-sectional view taken along the optical axis (axial principal ray) 1 from the center of the diaphragm 2 to the center of the image plane 3, and is a cross-sectional view taken along line A-A ′ in FIG. In this cross-sectional view, the surface before the incident surface 11 described later is not shown because it is not on this cross-section.

  The lateral aberration diagrams of the optical system of this example are shown in FIGS. In FIG. 12, (a) is the lateral aberration in the Y direction of the chief ray passing through zero in the X direction and zero in the Y direction, and (b) is zero in the X direction and zero in the Y direction. The lateral aberration in the Z direction of the principal ray passing through, (c) is zero in the X direction, and the transverse aberration in the Y direction of the principal ray passing through the maximum Y negative direction, (d) is zero in the X direction, Y Z-direction lateral aberration of the principal ray passing through the maximum negative field angle, (e) X-direction maximum field angle, Y-direction lateral aberration of the principal ray passing through the Y negative maximum field angle, (f) X positive Z-direction lateral aberration of the principal ray passing through the maximum directional field of view, Y negative maximum direction of view, (g) X-direction maximum maximal angle of view, Y-direction lateral aberration of the principal ray passing through zero in the Y-direction, (H) X-direction maximum field angle, Y-direction angle of view of principal ray passing through zero in the Z direction, and (i) X-direction maximum field angle, Y-direction maximum field angle of principal ray passing through zero. Y-direction lateral aberration, ( ) Is the lateral maximum aberration in the Z direction of the principal ray that passes through the maximum field angle in the X positive direction and the maximum field angle in the Y positive direction. In FIG. 13, (k) is the principal that passes through the maximum field angle in the X direction and zero in the X direction. Transverse aberration in the Y direction of the light beam, (l) is zero in the X direction, and lateral aberration in the Z direction of the principal ray passing through the maximum positive field in the Y positive direction, (m) is the maximum negative field angle in the X negative direction, and the positive Y direction Y-direction lateral aberration of the principal ray passing through the maximum field angle, (n) X-direction maximum field angle, Z-direction lateral aberration of the Y-direction maximum field angle, and (o) X-direction field angle. Is zero, the lateral aberration in the Y direction of the principal ray passing through the maximum Y negative direction angle, (p) is the lateral aberration in the Z direction of the principal ray passing through the maximum X field angle in the X negative direction, (q ) Is the maximum negative field angle in the X negative direction and the transverse aberration in the Y direction of the principal ray passing through the maximum negative field angle in the Y negative direction, and (r) is the Z direction of the principal ray passing through the maximum field angle in the negative X direction and the maximum negative field angle in the Y direction. Shows the lateral aberration of There. The Y direction and Z direction here are based on the origin of the optical system.

  The optical system according to the first embodiment includes, in order from the object side, a cover glass CG1, a front group optical element 10, an aperture stop 2, a rear group optical element 20, and a cover glass CG2. Yes. In the figure, 3 is an image plane (imaging plane).

  The cover glasses CG1 and CG2 are formed in a parallel plate shape.

  The optical element 10 has an incident surface 11, a reflecting surface 12, and an exit surface 13 as optical function surfaces. This optical element 10 is an eccentric prism. The axial principal ray 1 incident through the incident surface 11 is internally reflected by the reflecting surface 12, refracted by the exit surface 14, and exits from the optical element 10.

  The optical element 20 includes an incident surface 21, a reflecting surface 22, a reflecting surface 23, and an exit surface 24 as optical function surfaces. This optical element 20 is also an eccentric prism. The axial principal ray 1 incident through the incident surface 21 is internally reflected by the reflecting surface 22 and then internally reflected by the reflecting surface 23. Subsequently, the axial principal ray 1 is refracted by the exit surface 24 and exits from the optical element 20. The axial principal ray 1 from the incident surface 21 toward the reflecting surface 22 and the axial principal ray 1 from the reflecting surface 23 toward the exit surface 24 intersect in the optical element 20. In other words, the incident surface 21, the reflecting surface 22, the reflecting surface 23, and the exit surface 24 are arranged so that the axial principal rays 1 intersect each other. Here, when viewed from the positive direction of the Z-axis, the axial principal ray 1 proceeds to rotate counterclockwise within the optical element 20.

  The incident surface 11, the reflecting surface 12, and the exit surface 13 of the optical element 10 and the incident surface 21, the reflecting surface 22, the reflecting surface 23, and the exit surface 24 of the optical element 20 are all formed into a free-form surface shape. These surfaces have rotationally asymmetric power. Further, the incident surface 11, the reflecting surface 12, and the exit surface 13 of the optical element 10 are decentered in the YZ plane, and the incident surface 21, the reflecting surface 22, the reflecting surface 23, and the exit surface 24 of the optical element 20 are X -Eccentric in the Y plane.

  In the optical system of this embodiment, the axial principal ray 1 emitted from the center of a distant object passes through the cover glass CG1, the optical element 10, the center of the aperture stop 2, the optical element 20 and the cover glass CG2, and the image plane 3 Reach the center and image the object.

  In this embodiment, measures are taken to prevent the generation of ghost light and noise light. Specifically, for example, a light shielding member such as black paint is applied to a surface portion other than the effective area of the emission surface 13 of the optical element 10. Further, a light absorbing member may be provided outside the aperture stop 2 so as to be integrated with the aperture stop 2. Even in this way, generation of ghost light and noise light can be prevented.

  Here, the shape of the surface of the free-form surface used for defining the optical function surfaces 11 to 13 and 21 to 24 of Example 1 is a free-form surface defined by the equation (a). The Z-axis is the axis of the free-form surface. The definition of the power and focal length of the decentered optical system is defined based on FIG. 15 of US Pat. No. 6,124,989 (Japanese Patent Laid-Open No. 2000-66105), for example. The definition of the surface of the free-form surface and the power and focal length of the decentered optical system are the same in the following embodiments.

  Numerical data of this embodiment will be described later. In the numerical data, “FFS” indicates a free-form surface and “RE” indicates a reflecting surface. The refractive index and Abbe number are those of the d line. These are common in the numerical data of the following embodiments.

  In addition, all the eccentric amounts in the numerical data described later are shown as eccentric amounts based on the first surface (the origin set on the first surface CG1a of the cover glass CG1 in FIG. 2). The same applies to the following embodiments.

  In this embodiment, the image shape is electrically corrected by using different correction parameters for each wavelength region. Thereby, asymmetric image distortion and color blur can be effectively corrected. As a result, a preferable image shape and image quality can be obtained.

  FIG. 3 is a view similar to FIG. 2 showing the arrangement and optical path of the optical system according to Example 2 of the present invention.

  FIGS. 14 and 15 show lateral aberration diagrams similar to FIGS. 12 and 13 of the optical system of Example 2, respectively.

  Since the configuration of the optical system is the same as that of the first embodiment, detailed description thereof is omitted. Numerical data of this embodiment will be described later.

  FIG. 4 is a view similar to FIG. 2 showing the arrangement and optical path of the optical system according to Example 3 of the present invention.

  FIGS. 16 and 17 show lateral aberration diagrams similar to FIGS. 12 and 13 of the optical system of Example 3, respectively.

  Since the configuration of the optical system is the same as that of the first embodiment, detailed description thereof is omitted. Numerical data of this embodiment will be described later.

  FIG. 5 is a view similar to FIG. 2 showing the arrangement and optical path of an optical system according to Embodiment 4 of the present invention.

  FIGS. 18 and 19 show lateral aberration diagrams of the optical system of Example 4 similar to FIGS. 12 and 13, respectively.

  The optical system of Example 4 includes, in order from the object side, a cover glass CG1, a front group optical element 10, an aperture stop 2, a rear group optical element 20, and a cover glass CG2. Yes. In the figure, 3 is an image plane (imaging plane).

  The cover glasses CG1 and CG2 are formed in a parallel plate shape.

  The optical element 10 has an incident surface 11, a reflecting surface 12, and an exit surface 13 as optical function surfaces. This optical element 10 is an eccentric prism. The axial principal ray 1 incident through the incident surface 11 is internally reflected by the reflecting surface 12, refracted by the exit surface 14, and exits from the optical element 10.

  The optical element 20 has an incident surface 21, a reflecting surface 22, and an exit surface 23 as optical function surfaces. This optical element 20 is also an eccentric prism. The axial principal ray 1 incident through the incident surface 21 is internally reflected by the reflecting surface 22, is refracted by the exit surface 23, and exits from the optical element 20.

  The incident surface 11, the reflecting surface 12, and the exit surface 13 of the optical element 10 and the incident surface 21, the reflecting surface 22, and the exit surface 23 of the optical element 20 are all formed in a free-form surface shape. These surfaces have rotationally asymmetric power. The incident surface 11, the reflecting surface 12 and the exit surface 13 of the optical element 10 are decentered in the YZ plane, and the incident surface 21, the reflecting surface 22 and the exit surface 23 of the optical element 20 are in the XY plane. Is eccentric.

  In the optical system of this embodiment, the axial principal ray 1 emitted from the center of a distant object passes through the cover glass CG1, the optical element 10, the center of the aperture stop 2, the optical element 20, and the cover glass CG2, and the image plane 3 Reach the center and image the object.

  In this embodiment, the image shape is electrically corrected by using different correction parameters for each wavelength region. Thereby, asymmetric image distortion and color blur can be effectively corrected. As a result, a preferable image shape and image quality can be obtained.

  Numerical data of this embodiment will be described later.

  FIG. 6 is a view similar to FIG. 2 showing the arrangement and optical path of the optical system according to Example 5 of the present invention.

  FIGS. 20 and 21 show lateral aberration diagrams similar to FIGS. 12 and 13 of the optical system of Example 5, respectively.

  Since the configuration of the optical system is the same as that of the fourth embodiment, detailed description thereof is omitted. Numerical data of this embodiment will be described later.

  FIG. 7 is a view similar to FIG. 2 showing the arrangement and optical path of the optical system according to Example 6 of the present invention.

  FIGS. 22 and 23 show lateral aberration diagrams similar to FIGS. 12 and 13 of the optical system of Example 6, respectively.

  The optical system of Example 6 includes, in order from the object side, a cover glass CG1, a front group optical element 10, an aperture stop 2, a rear group optical element 20, and a cover glass CG2. Yes. In the figure, 3 is an image plane (imaging plane).

  The cover glasses CG1 and CG2 are formed in a parallel plate shape.

  The optical element 10 includes an incident surface 11, a reflecting surface 12, a reflecting surface 13, and an exit surface 14 as optical function surfaces. This optical element 10 is an eccentric prism. The axial principal ray 1 incident through the incident surface 11 is internally reflected by the reflecting surface 12 and then internally reflected by the reflecting surface 13. Subsequently, the axial principal ray 1 is refracted by the exit surface 14 and exits from the optical element 10. The axial principal ray 1 from the incident surface 11 toward the reflecting surface 12 and the axial principal ray 1 from the reflecting surface 13 toward the exit surface 14 intersect within the optical element 10. That is, the incident surface 11, the reflecting surface 12, the reflecting surface 13, and the exit surface 14 are arranged so that the axial principal rays 1 intersect each other. Here, when viewed from the positive direction of the X axis, the axial principal ray 1 travels so as to rotate counterclockwise within the optical element 10.

  The optical element 20 includes an incident surface 21, a reflecting surface 22, a reflecting surface 23, and an exit surface 24 as optical function surfaces. This optical element 20 is also an eccentric prism. The axial principal ray 1 incident through the incident surface 21 is internally reflected by the reflecting surface 22, then internally reflected by the reflecting surface 23, refracted by the exit surface 24, and exits from the optical element 20. The axial principal ray 1 from the incident surface 21 toward the reflecting surface 22 and the axial principal ray 1 from the reflecting surface 23 toward the exit surface 24 intersect in the optical element 20. In other words, the incident surface 21, the reflecting surface 22, the reflecting surface 23, and the exit surface 24 are arranged so that the axial principal rays 1 intersect each other. Here, when viewed from the positive direction of the Z-axis, the axial principal ray 1 proceeds to rotate counterclockwise within the optical element 20.

  The incident surface 11, the reflecting surface 12, the reflecting surface 13, and the exit surface 14 of the optical element 10 and the incident surface 21, the reflecting surface 22, the reflecting surface 23, and the exit surface 24 of the optical element 20 are all formed in a free-form surface shape. ing. These surfaces have rotationally asymmetric power. Further, the incident surface 11, the reflecting surface 12, the reflecting surface 13, and the exit surface 14 of the optical element 10 are decentered in the YZ plane, and the incident surface 21, the reflecting surface 22, the reflecting surface 23, and the exit surface of the optical element 20. 24 is eccentric in the XY plane.

  In the optical system of this embodiment, the axial principal ray 1 emitted from the center of a distant object passes through the cover glass CG1, the optical element 10, the center of the aperture stop 2, the optical element 20, and the cover glass CG2, and the image plane 3 Reach the center and image the object.

  In this embodiment, the image shape is electrically corrected by using different correction parameters for each wavelength region. Thereby, asymmetric image distortion and color blur can be effectively corrected. As a result, a preferable image shape and image quality can be obtained.

  Numerical data of this embodiment will be described later.

  FIG. 8 is a view similar to FIG. 2 showing the arrangement and optical path of the optical system according to Example 7 of the present invention.

  FIGS. 24 and 25 show lateral aberration diagrams similar to FIGS. 12 and 13 of the optical system of Example 7, respectively.

  Since the configuration of the optical system is the same as that of the fourth embodiment, detailed description thereof is omitted. Numerical data of this embodiment will be described later. The curvature of the reflecting surface 12 of the optical element 10 of Example 7 in the X direction (spherical notch direction) is 0, and the coefficient indicating the surface has no term relating to X.

  FIG. 9 is a view similar to FIG. 2 showing the arrangement and optical path of the optical system according to Example 8 of the present invention.

  FIGS. 26 and 27 show lateral aberration diagrams similar to FIGS. 12 and 13, respectively, when the optical system of Example 8 is focused at infinity. Also, lateral aberration diagrams similar to those in FIGS. 12 and 13 at the time of close focus are shown in FIGS. 28 and 29, respectively.

  Since the configuration of the optical system is the same as that of the first embodiment, detailed description thereof is omitted. The optical system of the present embodiment performs focusing by moving the optical element 10 in the direction of the arrow in FIG. When close to the optical element 10, the optical element 10 moves downward in the direction of the arrow in FIG. Numerical data of this embodiment will be described later.

  FIG. 10 is a view similar to FIG. 2 showing the arrangement and optical path of the optical system according to Example 9 of the present invention.

  FIGS. 30 and 31 show lateral aberration diagrams similar to FIGS. 12 and 13, respectively, when the optical system of Example 9 is focused at infinity. In addition, FIGS. 32 and 33 show lateral aberration diagrams similar to those in FIGS.

  Since the configuration of the optical system is the same as that of the first embodiment, detailed description thereof is omitted. The optical system of the present embodiment performs focusing by moving the optical element 20 in the direction of the arrow in FIG. At the closest distance, the optical element 20 moves in the upper left direction of the arrow in FIG. Numerical data of this embodiment will be described later.

  FIG. 11 is a view similar to FIG. 2 showing the arrangement and optical path of the optical system according to Example 10 of the present invention.

  FIGS. 34 and 35 show lateral aberration diagrams similar to FIGS. 12 and 13, respectively, when the optical system of Example 10 is focused at infinity. In addition, lateral aberration diagrams similar to those in FIGS. 12 and 13 at the close focus are shown in FIGS. 36 and 37, respectively.

  Since the configuration of the optical system is the same as that of the fourth embodiment, detailed description thereof is omitted. The optical system of the present embodiment performs focusing by moving the optical element 10 in the direction of the arrow in FIG. At the closest distance, the optical element 10 moves downward in the direction of the arrow in FIG. Numerical data of this embodiment will be described later.

  Below, the numerical data of Examples 1-10 are shown.

Example 1
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 4.1mm
Focal length [Y]: 3.7mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.5842 30.5
4 FFS [2] (RE) Eccentricity (4) 1.5842 30.5
5 FFS [3] Eccentricity (5)
6 ∞ (diaphragm surface) Eccentricity (6)
7 FFS [4] Eccentricity (7) 1.5256 56.4
8 FFS [5] (RE) Eccentricity (8) 1.5256 56.4
9 FFS [6] (RE) Eccentricity (9) 1.5256 56.4
10 FFS [7] Eccentricity (10)
11 ∞ Eccentricity (11) 1.5163 64.1
12 ∞ Eccentricity (12)
Image plane ∞ Eccentricity (13)
FFS [1]
C ₄ 1.9752 × 10 ^-2 C ₆ 6.0861 × 10 ^-2 C ₈ -2.1810 × 10 ^-3
C ₁₀ -3.5006 × 10 ^-3 C ₁₁ 5.1509 × 10 ^-4 C ₁₃ 6.6310 × 10 ^-4
C ₁₅ 1.5687 × 10 ^-4
FFS [2]
C ₄ 1.7422 × 10 ^-4 C ₆ 2.7161 × 10 ^-2 C ₈ -7.9263 × 10 ^-4
C ₁₀ 1.0776 × 10 ^-3 C ₁₁ -4.0118 × 10 ^-5 C ₁₃ -2.0162 × 10 ^-4
C ₁₅ -2.7664 × 10 ^-5
FFS [3]
C ₄ 3.4298 × 10 ^-3 C ₆ 8.5707 × 10 ^-3 C ₈ -1.2238 × 10 ^-3
C ₁₀ 7.7644 × 10 ^-3 C ₁₁ 9.7427 × 10 ^-3 C ₁₃ -2.1673 × 10 ^-2
C ₁₅ -1.4252 × 10 ^-3
FFS [4]
C ₄ -3.7853 × 10 ^-2 C ₆ 2.4726 × 10 ^-1 C ₈ -2.8027 × 10 ^-3
C ₁₀ 3.6268 × 10 ^-3 C ₁₁ -7.9097 × 10 ^-4 C ₁₃ -2.3035 × 10 ^-2
C ₁₅ 1.8123 × 10 ^-2
FFS [5]
C ₄ 2.0890 × 10 ^-2 C ₆ 3.0672 × 10 ^-2 C ₈ -7.8752 × 10 ^-4
C ₁₀ 1.4443 × 10 ^-5 C ₁₁ -2.6216 × 10 ^-5 C ₁₃ 3.5995 × 10 ^-5
C ₁₅ 1.6708 × 10 ^-5
FFS [6]
C ₄ -1.7671 × 10 ^-2 C ₆ -1.2102 × 10 ^-2 C ₈ -1.6531 × 10 ^-3
C ₁₀ -8.4736 × 10 ^-4 C ₁₁ -1.6626 × 10 ^-5 C ₁₃ -8.7406 × 10 ^-5
C ₁₅ -4.4735 × 10 ^-5
FFS [7]
C ₄ 2.4963 × 10 ^-2 C ₆ -1.0095 × 10 ^-1 C ₈ -8.1546 × 10 ^-3
C ₁₀ -5.5282 × 10 ^-3 C ₁₁ -3.0733 × 10 ^-3 C ₁₃ -5.8691 × 10 ^-3
C ₁₅ 1.9688 × 10 ^-3
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentric (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y 0.00 Z 0.70
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y 0.00 Z 2.69
α -45.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y 3.80 Z 2.69
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 4.28 Z 2.69
α -90.00 β 0.00 γ 0.00
Eccentricity (7)
X 0.00 Y 4.50 Z 2.69
α -90.00 β 0.00 γ -90.00
Eccentricity (8)
X 0.00 Y 11.61 Z 2.69
α -90.00 β 18.33 γ -90.00
Eccentric (9)
X -2.78 Y 7.87 Z 2.69
α -90.00 β 63.77 γ -90.00
Eccentric (10)
X 3.09 Y 7.78 Z 2.69
α 90.00 β 88.00 γ 90.00
Eccentric (11)
X 3.61 Y 7.78 Z 2.69
α 0.00 β -90.00 γ 0.00
Eccentric (12)
X 3.91 Y 7.78 Z 2.69
α 0.00 β -90.00 γ 0.00
Eccentric (13)
X 4.53 Y 7.78 Z 2.69
α 0.00 β -90.00 γ 0.00.

Example 2
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 4.1mm
Focal length [Y]: 3.6mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.5842 30.5
4 FFS [2] (RE) Eccentricity (4) 1.5842 30.5
5 FFS [3] Eccentricity (5)
6 ∞ (diaphragm surface) Eccentricity (6)
7 FFS [4] Eccentricity (7) 1.5256 56.4
8 FFS [5] (RE) Eccentricity (8) 1.5256 56.4
9 FFS [6] (RE) Eccentricity (9) 1.5256 56.4
10 FFS [7] Eccentricity (10)
11 ∞ Eccentricity (11) 1.5163 64.1
12 ∞ Eccentricity (12)
Image plane ∞ Eccentricity (13)
FFS [1]
C ₄ 2.1366 × 10 ^-2 C ₆ 6.9035 × 10 ^-2 C ₈ 3.0084 × 10 ^-4
C ₁₀ -4.6241 × 10 ^-3 C ₁₁ 4.4574 × 10 ^-4 C ₁₃ 7.3373 × 10 ^-4
C ₁₅ 4.2539 × 10 ^-4
FFS [2]
C ₄ 9.2833 × 10 ^-4 C ₆ 2.8526 × 10 ^-2 C ₈ -1.0384 × 10 ^-3
C ₁₀ 8.2126 × 10 ^-4 C ₁₁ 2.7293 × 10 ^-5 C ₁₃ -1.6379 × 10 ^-4
C ₁₅ -8.3839 × 10 ^-5
FFS [3]
C ₄ -9.2434 × 10 ^-3 C ₆ -4.5319 × 10 ^-3 C ₈ -9.8337 × 10 ^-3
C ₁₀ 7.2874 × 10 ^-3 C ₁₁ 9.0652 × 10 ^-3 C ₁₃ -1.8192 × 10 ^-2
C ₁₅ -1.7790 × 10 ^-3
FFS [4]
C ₄ -4.5834 × 10 ^-2 C ₆ 2.2522 × 10 ^-1 C ₇ -9.8797 × 10 ^-4
C ₈ -2.3361 × 10 ^-3 C ₉ 9.2701 × 10 ^-4 C ₁₀ 2.4411 × 10 ^-3
C ₁₁ -5.9122 × 10 ^-4 C ₁₂ 1.7361 × 10 ^-4 C ₁₃ -1.8242 × 10 ^-2
C ₁₄ 1.2584 × 10 ^-5 C ₁₅ 1.6159 × 10 ^-2
FFS [5]
C ₄ 2.0528 × 10 ^-2 C ₆ 2.9875 × 10 ^-2 C ₇ -4.2166 × 10 ^-5
C ₈ -6.9711 × 10 ^-4 C ₉ -9.8063 × 10 ^-5 C ₁₀ -5.9507 × 10 ^-5
C ₁₁ -1.8875 × 10 ^-5 C ₁₂ 6.7699 × 10 ^-6 C ₁₃ 5.2455 × 10 ^-5
C ₁₄ -1.9258 × 10 ^-5 C ₁₅ 2.3219 × 10 ^-5
FFS [6]
C ₄ -1.7756 × 10 ^-2 C ₆ -1.2013 × 10 ^-2 C ₇ 4.8486 × 10 ^-6
C ₈ -1.5375 × 10 ^-3 C ₉ 9.5416 × 10 ^-5 C ₁₀ -9.3881 × 10 ^-4
C ₁₁ -8.9675 × 10 ^-6 C ₁₂ 1.2098 × 10 ^-5 C ₁₃ -7.3535 × 10 ^-5
C ₁₄ -1.2286 × 10 ^-5 C ₁₅ -4.8407 × 10 ^-5
FFS [7]
C ₄ 3.7412 × 10 ^-2 C ₆ -8.6455 × 10 ^-2 C ₇ 1.0895 × 10 ^-3
C ₈ -1.0188 × 10 ^-2 C ₉ 7.2058 × 10 ^-3 C ₁₀ -6.2964 × 10 ^-3
C ₁₁ -4.8071 × 10 ^-3 C ₁₂ 1.1183 × 10 ^-3 C ₁₃ -8.2850 × 10 ^-3
C ₁₄ 6.4640 × 10 ^-4 C ₁₅ -8.6390 × 10 ^-4
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentric (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y 0.00 Z 0.70
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y 0.00 Z 2.71
α -45.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y 4.15 Z 2.71
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 4.69 Z 2.71
α -90.00 β 0.00 γ 0.00
Eccentricity (7)
X 0.00 Y 4.91 Z 2.71
α -90.00 β 0.00 γ -90.00
Eccentricity (8)
X 0.00 Y 12.16 Z 2.71
α -90.00 β 18.52 γ -90.00
Eccentric (9)
X -2.86 Y 8.37 Z 2.71
α -90.00 β 63.96 γ -90.00
Eccentric (10)
X 3.17 Y 8.28 Z 2.71
α 90.00 β 87.96 γ 90.00
Eccentric (11)
X 3.67 Y 8.27 Z 2.71
α 0.00 β -90.00 γ 0.00
Eccentric (12)
X 3.97 Y 8.27 Z 2.71
α 0.00 β -90.00 γ 0.00
Eccentric (13)
X 4.59 Y 8.27 Z 2.71
α 0.00 β -90.00 γ 0.00.

Example 3
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 4.1mm
Focal length [Y]: 3.5mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.5842 30.5
4 FFS [2] (RE) Eccentricity (4) 1.5842 30.5
5 FFS [3] Eccentricity (5)
6 ∞ (diaphragm surface) Eccentricity (6)
7 FFS [4] Eccentricity (7) 1.5256 56.4
8 FFS [5] (RE) Eccentricity (8) 1.5256 56.4
9 FFS [6] (RE) Eccentricity (9) 1.5256 56.4
10 FFS [7] Eccentricity (10)
11 ∞ Eccentricity (11) 1.5163 64.1
12 ∞ Eccentricity (12)
Image plane ∞ Eccentricity (13)
FFS [1]
C ₄ 2.1931 × 10 ^-2 C ₆ 6.8717 × 10 ^-2 C ₇ 3.4411 × 10 ^-4
C ₈ 3.5676 × 10 ^-4 C ₉ -3.4811 × 10 ^-4 C ₁₀ -4.7333 × 10 ^-3
C ₁₁ 5.0764 × 10 ^-4 C ₁₂ 1.3485 × 10 ^-5 C ₁₃ 7.0733 × 10 ^-4
C ₁₄ -1.0676 × 10 ^-4 C ₁₅ 5.1878 × 10 ^-4
FFS [2]
C ₄ 8.6611 × 10 ^-4 C ₆ 2.8606 × 10 ^-2 C ₇ 9.2301 × 10 ^-5
C ₈ -1.1912 × 10 ^-3 C ₉ -1.4301 × 10 ^-4 C ₁₀ 7.7117 × 10 ^-4
C ₁₁ 1.7891 × 10 ^-5 C ₁₂ -4.5229 × 10 ^-5 C ₁₃ -1.5975 × 10 ^-4
C ₁₄ -1.1805 × 10 ^-5 C ₁₅ -9.8078 × 10 ^-5
FFS [3]
C ₄ -1.1310 × 10 ^-2 C ₆ -5.8669 × 10 ^-3 C ₇ -1.4710 × 10 ^-3
C ₈ -1.0938 × 10 ^-2 C ₉ 4.9805 × 10 ^-3 C ₁₀ 6.8942 × 10 ^-3
C ₁₁ 9.4849 × 10 ^-3 C ₁₂ -2.1540 × 10 ^-3 C ₁₃ -1.8442 × 10 ^-2
C ₁₄ 3.1132 × 10 ^-4 C ₁₅ -2.3800 × 10 ^-3
FFS [4]
C ₄ -4.5627 × 10 ^-2 C ₆ 2.2986 × 10 ^-1 C ₇ -9.9037 × 10 ^-4
C ₈ 3.3507 × 10 ^-3 C ₉ 8.7221 × 10 ^-4 C ₁₀ 1.2509 × 10 ^-3
C ₁₁ -9.1674 × 10 ^-4 C ₁₂ -2.4042 × 10 ^-4 C ₁₃ -1.8760 × 10 ^-2
C ₁₄ 2.4577 × 10 ^-3 C ₁₅ 1.7002 × 10 ^-2
FFS [5]
C ₄ 2.0922 × 10 ^-2 C ₆ 3.0345 × 10 ^-2 C ₇ -7.3195 × 10 ^-5
C ₈ -6.8327 × 10 ^-4 C ₉ -8.8903 × 10 ^-5 C ₁₀ -3.9062 × 10 ^-5
C ₁₁ -4.6768 × 10 ^-6 C ₁₂ 1.0935 × 10 ^-5 C ₁₃ 5.7807 × 10 ^-5
C ₁₄ -1.4105 × 10 ^-5 C ₁₅ 2.5929 × 10 ^-5
FFS [6]
C ₄ -1.7231 × 10 ^-2 C ₆ -1.1261 × 10 ^-2 C ₇ -2.8473 × 10 ^-5
C ₈ -1.6349 × 10 ^-3 C ₉ 1.3061 × 10 ^-4 C ₁₀ -8.8022 × 10 ^-4
C ₁₁ 1.4363 × 10 ^-5 C ₁₂ 1.9348 × 10 ^-5 C ₁₃ -8.2933 × 10 ^-5
C ₁₄ -1.0730 × 10 ^-5 C ₁₅ -4.3906 × 10 ^-5
FFS [7]
C ₄ 4.1312 × 10 ^-2 C ₆ -7.9781 × 10 ^-2 C ₇ 1.6090 × 10 ^-3
C ₈ -8.4367 × 10 ^-3 C ₉ 6.7578 × 10 ^-3 C ₁₀ -4.5789 × 10 ^-3
C ₁₁ -5.4262 × 10 ^-3 C ₁₂ -1.2258 × 10 ^-4 C ₁₃ -9.3727 × 10 ^-3
C ₁₄ 1.3003 × 10 ^-3 C ₁₅ -2.2055 × 10 ^-4
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentric (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y 0.00 Z 0.70
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y 0.00 Z 2.70
α -45.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y 4.16 Z 2.70
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 4.67 Z 2.70
α -90.00 β 0.00 γ 0.00
Eccentricity (7)
X 0.00 Y 4.89 Z 2.70
α -90.00 β 0.00 γ -90.00
Eccentricity (8)
X 0.00 Y 12.18 Z 2.70
α -90.00 β 18.30 γ -90.00
Eccentric (9)
X -2.85 Y 8.34 Z 2.70
α -90.00 β 63.70 γ -90.00
Eccentric (10)
X 3.24 Y 8.26 Z 2.70
α 90.00 β 88.34 γ 90.00
Eccentric (11)
X 3.72 Y 8.25 Z 2.70
α 0.00 β -90.00 γ 0.00
Eccentric (12)
X 4.02 Y 8.25 Z 2.70
α 0.00 β -90.00 γ 0.00
Eccentric (13)
X 4.65 Y 8.25 Z 2.70
α 0.00 β -90.00 γ 0.00.

Example 4
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 4.1mm
Focal length [Y]: 4.4mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.5256 56.4
4 FFS [2] (RE) Eccentricity (4) 1.5256 56.4
5 FFS [3] Eccentricity (5)
6 ∞ (diaphragm surface) Eccentricity (6)
7 FFS [4] Eccentricity (7) 1.5256 56.4
8 FFS [5] (RE) Eccentricity (8) 1.5256 56.4
9 FFS [6] Eccentricity (9)
10 ∞ Eccentricity (10) 1.5163 64.1
11 ∞ Eccentricity (11)
Image plane ∞ Eccentricity (12)
FFS [1]
C ₄ 3.9616 × 10 ^-2 C ₆ -4.2054 × 10 ^-2 C ₈ 1.3727 × 10 ^-3
C ₁₀ 6.4585 × 10 ^-3 C ₁₁ -9.5394 × 10 ^-4 C ₁₃ -5.3679 × 10 ^-3
C ₁₅ -4.4338 × 10 ^-3
FFS [2]
C ₄ -3.3462 × 10 ^-5 C ₆ -9.0793 × 10 ^-3 C ₈ 3.9190 × 10 ^-4
C ₁₀ 1.6208 × 10 ^-4 C ₁₁ -3.4593 × 10 ^-6 C ₁₃ -1.7121 × 10 ^-5
C ₁₅ -3.1413 × 10 ^-5
FFS [3]
C ₄ 3.3987 × 10 ^-2 C ₆ 1.1125 × 10 ^-1 C ₈ 9.4059 × 10 ^-4
C ₁₀ -3.4179 × 10 ^-3 C ₁₁ -3.3500 × 10 ^-3 C ₁₃ -7.0494 × 10 ^-4
C ₁₅ -2.1413 × 10 ^-3
FFS [4]
C ₄ -7.4417 × 10 ^-2 C ₆ -5.8730 × 10 ^-2 C ₈ 2.5042 × 10 ^-3
C ₁₀ -2.1917 × 10 ^-2 C ₁₁ -4.9969 × 10 ^-3 C ₁₃ -9.1821 × 10 ^-3
C ₁₅ 7.0674 × 10 ^-4
FFS [5]
C ₄ 3.6834 × 10 ^-3 C ₆ 2.5557 × 10 ^-2 C ₈ 1.0064 × 10 ^-3
C ₁₀ 1.3099 × 10 ^-4 C ₁₁ -4.2399 × 10 ^-4 C ₁₃ -9.6762 × 10 ^-4
C ₁₅ 4.3159 × 10 ^-4
FFS [6]
C ₄ 2.3016 × 10 ^-2 C ₆ 5.3844 × 10 ^-2 C ₈ 4.2404 × 10 ^-3
C ₁₀ 2.0380 × 10 ^-2 C ₁₁ -6.8972 × 10 ^-3 C ₁₃ -5.4397 × 10 ^-3
C ₁₅ 7.2070 × 10 ^-3
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentricity (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y 0.00 Z 0.96
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y 0.00 Z 3.82
α -45.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y 2.39 Z 3.82
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 3.40 Z 3.82
α -90.00 β 0.00 γ 0.00
Eccentricity (7)
X 0.00 Y 3.60 Z 3.82
α -90.00 β 0.00 γ -90.00
Eccentricity (8)
X 0.00 Y 5.35 Z 3.82
α -90.00 β -46.03 γ -90.00
Eccentric (9)
X 1.93 Y 5.41 Z 3.82
α 90.00 β -83.95 γ 90.00
Eccentricity (10)
X 2.32 Y 5.41 Z 3.82
α 0.00 β -90.00 γ 0.00
Eccentric (11)
X 2.62 Y 5.41 Z 3.82
α 0.00 β -90.00 γ 0.00
Eccentric (12)
X 3.24 Y 5.41 Z 3.82
α 0.00 β -90.00 γ 0.00.

Example 5
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 4.0mm
Focal length [Y]: 4.3mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.5256 56.4
4 FFS [2] (RE) Eccentricity (4) 1.5256 56.4
5 FFS [3] Eccentricity (5)
6 ∞ (diaphragm surface) Eccentricity (6)
7 FFS [4] Eccentricity (7) 1.5256 56.4
8 FFS [5] (RE) Eccentricity (8) 1.5256 56.4
9 FFS [6] Eccentricity (9)
10 ∞ Eccentricity (10) 1.5163 64.1
11 ∞ Eccentricity (11)
Image plane ∞ Eccentricity (12)
FFS [1]
C ₄ 4.2266 × 10 ^-2 C ₆ -4.4799 × 10 ^-2 C ₈ 8.7203 × 10 ^-4
C ₁₀ 7.0054 × 10 ^-3 C ₁₁ -1.3889 × 10 ^-3 C ₁₃ -7.2215 × 10 ^-3
C ₁₅ -5.8584 × 10 ^-3
FFS [2]
C ₄ 3.0582 × 10 ^-5 C ₆ -8.6401 × 10 ^-3 C ₈ 1.9951 × 10 ^-4
C ₁₀ 1.7849 × 10 ^-4 C ₁₁ -1.1989 × 10 ^-5 C ₁₃ -5.6367 × 10 ^-5
C ₁₅ -6.8646 × 10 ^-5
FFS [3]
C ₄ 3.7482 × 10 ^-2 C ₆ 1.1994 × 10 ^-1 C ₈ 4.4719 × 10 ^-4
C ₁₀ -3.9973 × 10 ^-3 C ₁₁ -3.2342 × 10 ^-3 C ₁₃ 2.8310 × 10 ^-4
C ₁₅ -2.0528 × 10 ^-3
FFS [4]
C ₄ -7.6534 × 10 ^-2 C ₆ -5.2456 × 10 ^-2 C ₈ 2.7445 × 10 ^-3
C ₁₀ -2.2625 × 10 ^-2 C ₁₁ -5.4339 × 10 ^-3 C ₁₃ -8.8405 × 10 ^-3
C ₁₅ 5.1742 × 10 ^-4
FFS [5]
C ₄ 4.0645 × 10 ^-3 C ₆ 2.6032 × 10 ^-2 C ₈ 1.2188 × 10 ^-3
C ₁₀ 1.8484 × 10 ^-4 C ₁₁ -5.6907 × 10 ^-4 C ₁₃ -9.9903 × 10 ^-4
C ₁₅ 4.3353 × 10 ^-4
FFS [6]
C ₄ 2.1603 × 10 ^-2 C ₆ 5.8156 × 10 ^-2 C ₈ 6.0968 × 10 ^-3
C ₁₀ 2.2412 × 10 ^-2 C ₁₁ -3.7661 × 10 ^-3 C ₁₃ -3.0283 × 10 ^-3
C ₁₅ 8.1590 × 10 ^-3
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentricity (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y 0.00 Z 0.94
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y 0.00 Z 3.01
α -45.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y 2.33 Z 3.01
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 3.28 Z 3.01
α -90.00 β 0.00 γ 0.00
Eccentricity (7)
X 0.00 Y 3.48 Z 3.01
α -90.00 β 0.00 γ -90.00
Eccentricity (8)
X 0.00 Y 5.19 Z 3.01
α -90.00 β -46.10 γ -90.00
Eccentric (9)
X 1.89 Y 5.26 Z 3.01
α 90.00 β -83.63 γ 90.00
Eccentricity (10)
X 2.29 Y 5.29 Z 3.01
α 0.00 β -90.00 γ 0.00
Eccentric (11)
X 2.59 Y 5.29 Z 3.01
α 0.00 β -90.00 γ 0.00
Eccentric (12)
X 3.21 Y 5.29 Z 3.01
α 0.00 β -90.00 γ 0.00.

Example 6
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 4.0mm
Focal length [Y]: 4.0mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.6069 27.0
4 FFS [2] (RE) Eccentricity (4) 1.6069 27.0
5 FFS [3] (RE) Eccentricity (5) 1.6069 27.0
6 FFS [4] Eccentricity (6)
7 ∞ (diaphragm surface) Eccentricity (7)
8 FFS [5] Eccentricity (8) 1.5256 56.4
9 FFS [6] (RE) Eccentricity (9) 1.5256 56.4
10 FFS [7] (RE) Eccentricity (10) 1.5256 56.4
11 FFS [8] Eccentricity (11)
12 ∞ Eccentricity (12) 1.5163 64.1
13 ∞ Eccentricity (13)
Image plane ∞ Eccentricity (14)
FFS [1]
C ₄ 1.6091 × 10 ^-2 C ₆ 1.7007 × 10 ^-2 C ₈ 8.5578 × 10 ^-5
C ₁₀ 5.6459 × 10 ^-5 C ₁₁ 2.1816 × 10 ^-5 C ₁₃ 2.9986 × 10 ^-4
C ₁₅ -2.5255 × 10 ^-4
FFS [2]
C ₄ 1.2306 × 10 ^-2 C ₆ 4.4210 × 10 ^-2 C ₈ -3.3468 × 10 ^-4
C ₁₀ -2.3918 × 10 ^-3 C ₁₁ 3.2048 × 10 ^-5 C ₁₃ -2.0511 × 10 ^-5
C ₁₅ 1.3173 × 10 ^-4
FFS [3]
C ₄ -1.8468 × 10 ^-2 C ₆ 1.7145 × 10 ^-2 C ₈ -1.9670 × 10 ^-4
C ₁₀ -1.2147 × 10 ^-3 C ₁₁ -1.0462 × 10 ^-4 C ₁₃ -5.6839 × 10 ^-4
C ₁₅ 2.3997 × 10 ^-5
FFS [4]
C ₄ -4.6313 × 10 ^-4 C ₆ 4.7743 × 10 ^-3 C ₈ -8.6361 × 10 ^-4
C ₁₀ -2.6606 × 10 ^-4
FFS [5]
C ₄ 1.7539 × 10 ^-2 C ₆ 2.4793 × 10 ^-2 C ₈ 1.8102 × 10 ^-4
C ₁₀ 3.3830 × 10 ^-3 C ₁₁ -4.7712 × 10 ^-5 C ₁₃ 7.9555 × 10 ^-4
C ₁₅ -7.5888 × 10 ^-4
FFS [6]
C ₄ -1.4471 × 10 ^-2 C ₆ -1.7526 × 10 ^-2 C ₈ -1.3089 × 10 ^-4
C ₁₀ 4.3751 × 10 ^-4 C ₁₁ -9.2316 × 10 ^-6 C ₁₃ 3.4973 × 10 ^-5
C ₁₅ -4.9484 × 10 ^-5
FFS [7]
C ₄ 1.5531 × 10 ^-2 C ₆ 1.1525 × 10 ^-2 C ₈ -5.9797 × 10 ^-4
C ₁₀ -1.4998 × 10 ^-6 C ₁₁ 1.3856 × 10 ^-6 C ₁₃ 3.5283 × 10 ^-5
C ₁₅ -5.4624 × 10 ^-5
FFS [8]
C ₄ 4.9833 × 10 ^-2 C ₆ 3.3573 × 10 ^-2 C ₈ -2.2342 × 10 ^-3
C ₁₀ 1.1149 × 10 ^-4 C ₁₁ 3.6664 × 10 ^-4 C ₁₃ 2.0997 × 10 ^-3
C ₁₅ -6.9195 × 10 ^-4
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentric (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y 0.00 Z 0.71
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y 0.00 Z 6.31
α 28.01 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y -3.71 Z 3.81
α 73.01 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 2.90 Z 3.81
α 90.00 β 0.00 γ 0.00
Eccentricity (7)
X 0.00 Y 3.11 Z 3.81
α -90.00 β 0.00 γ 0.00
Eccentricity (8)
X 0.00 Y 3.21 Z 3.81
α 90.00 β 0.00 γ 90.00
Eccentric (9)
X -0.00 Y 9.03 Z 3.81
α 90.00 β -21.10 γ 90.00
Eccentric (10)
X -2.93 Y 5.80 Z 3.81
α 90.00 β -66.19 γ 90.00
Eccentric (11)
X 2.31 Y 5.78 Z 3.81
α -90.00 β -89.56 γ -90.00
Eccentric (12)
X 5.01 Y 5.79 Z 3.81
α 0.00 β -90.00 γ 0.00
Eccentric (13)
X 5.31 Y 5.79 Z 3.81
α 0.00 β -90.00 γ 0.00
Eccentric (14)
X 5.94 Y 5.79 Z 3.81
α 0.00 β -90.00 γ 0.00.

Example 7
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 4.3mm
Focal length [Y]: 4.0mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.5256 56.4
4 FFS [2] (RE) Eccentricity (4) 1.5256 56.4
5 FFS [3] Eccentricity (5)
6 ∞ (diaphragm surface) Eccentricity (6)
7 FFS [4] Eccentricity (7) 1.5256 56.4
8 FFS [5] (RE) Eccentricity (8) 1.5256 56.4
9 FFS [6] Eccentricity (9)
10 ∞ Eccentricity (10) 1.5163 64.1
11 ∞ Eccentricity (11)
Image plane ∞ Eccentricity (12)
FFS [1]
C ₄ 4.3629 × 10 ^-2 C ₆ -3.5958 × 10 ^-2 C ₈ 1.2045 × 10 ^-4
C ₁₀ 5.4092 × 10 ^-3 C ₁₁ -1.5101 × 10 ^-3 C ₁₃ -7.0489 × 10 ^-3
C ₁₅ -5.3215 × 10 ^-3
FFS [2]
C ₆ -8.1441 × 10 ^-3 C ₁₀ 2.2177 × 10 ^-5 C ₁₅ -3.9365 × 10 ^-5
FFS [3]
C ₄ 3.9640 × 10 ^-2 C ₆ 1.1831 × 10 ^-1 C ₈ -1.9797 × 10 ^-4
C ₁₀ -4.5637 × 10 ^-3 C ₁₁ -3.7810 × 10 ^-3 C ₁₃ 2.4290 × 10 ^-4
C ₁₅ -2.2506 × 10 ^-3
FFS [4]
C ₄ -7.4882 × 10 ^-2 C ₆ -4.4540 × 10 ^-2 C ₈ 2.5029 × 10 ^-3
C ₁₀ -2.3411 × 10 ^-2 C ₁₁ -5.7378 × 10 ^-3 C ₁₃ -8.7523 × 10 ^-3
C ₁₅ -1.4576 × 10 ^-4
FFS [5]
C ₄ 4.2957 × 10 ^-3 C ₆ 2.6698 × 10 ^-2 C ₈ 1.1585 × 10 ^-3
C ₁₀ 1.9793 × 10 ^-4 C ₁₁ -6.6443 × 10 ^-4 C ₁₃ -9.6415 × 10 ^-4
C ₁₅ 4.2278 × 10 ^-4
FFS [6]
C ₄ 1.1685 × 10 ^-2 C ₆ 6.1242 × 10 ^-2 C ₈ 6.5990 × 10 ^-3
C ₁₀ 2.3694 × 10 ^-2 C ₁₁ -1.0188 × 10 ^-3 C ₁₃ -2.2547 × 10 ^-3
C ₁₅ 7.7475 × 10 ^-3
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentric (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y 0.00 Z 0.89
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y 0.00 Z 3.01
α -45.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y 2.18 Z 3.01
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 3.01 Z 3.01
α -90.00 β 0.00 γ 0.00
Eccentricity (7)
X 0.00 Y 3.21 Z 3.01
α -90.00 β 0.00 γ -90.00
Eccentricity (8)
X 0.00 Y 4.93 Z 3.01
α -90.00 β -46.16 γ -90.00
Eccentric (9)
X 1.90 Y 5.00 Z 3.01
α 90.00 β -83.35 γ 90.00
Eccentric (10)
X 2.30 Y 5.02 Z 3.01
α 0.00 β -90.00 γ 0.00
Eccentric (11)
X 2.60 Y 5.02 Z 3.01
α 0.00 β -90.00 γ 0.00
Eccentric (12)
X 3.22 Y 5.02 Z 3.01
α 0.00 β -90.00 γ 0.00.

Example 8
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 4.0mm
Focal length [Y]: 3.6mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.5842 30.5
4 FFS [2] (RE) Eccentricity (4) 1.5842 30.5
5 FFS [3] Eccentricity (5)
6 ∞ (diaphragm surface) Eccentricity (6)
7 FFS [4] Eccentricity (7) 1.5256 56.4
8 FFS [5] (RE) Eccentricity (8) 1.5256 56.4
9 FFS [6] (RE) Eccentricity (9) 1.5256 56.4
10 FFS [7] Eccentricity (10)
11 ∞ Eccentricity (11) 1.5163 64.1
12 ∞ Eccentricity (12)
Image plane ∞ Eccentricity (13)
FFS [1]
C ₄ 2.0546 × 10 ^-2 C ₆ 6.0876 × 10 ^-2 C ₈ -1.6941 × 10 ^-3
C ₁₀ -3.7164 × 10 ^-3 C ₁₁ 5.8505 × 10 ^-4 C ₁₃ 5.1260 × 10 ^-4
C ₁₅ 2.7272 × 10 ^-4
FFS [2]
C ₄ 2.3414 × 10 ^-4 C ₆ 2.7979 × 10 ^-2 C ₈ -6.0094 × 10 ^-4
C ₁₀ 9.5370 × 10 ^-4 C ₁₁ -3.8800 × 10 ^-5 C ₁₃ -1.6408 × 10 ^-4
C ₁₅ -4.0821 × 10 ^-5
FFS [3]
C ₄ -1.0188 × 10 ^-2 C ₆ 4.8395 × 10 ^-3 C ₈ -8.2611 × 10 ^-4
C ₁₀ 6.8637 × 10 ^-3 C ₁₁ 6.3207 × 10 ^-3 C ₁₃ -1.9246 × 10 ^-2
C ₁₅ -2.0395 × 10 ^-3
FFS [4]
C ₄ -4.0932 × 10 ^-2 C ₆ 2.3444 × 10 ^-1 C ₈ -2.7353 × 10 ^-3
C ₁₀ 3.3573 × 10 ^-3 C ₁₁ -1.2551 × 10 ^-3 C ₁₃ -1.9912 × 10 ^-2
C ₁₅ 1.3156 × 10 ^-2
FFS [5]
C ₄ 2.0899 × 10 ^-2 C ₆ 3.0111 × 10 ^-2 C ₈ -8.0779 × 10 ^-4
C ₁₀ 2.2131 × 10 ^-5 C ₁₁ -3.9723 × 10 ^-5 C ₁₃ 4.6809 × 10 ^-5
C ₁₅ 1.8799 × 10 ^-5
FFS [6]
C ₄ -1.7704 × 10 ^-2 C ₆ -1.2732 × 10 ^-2 C ₈ -1.6848 × 10 ^-3
C ₁₀ -8.4758 × 10 ^-4 C ₁₁ -2.0887 × 10 ^-5 C ₁₃ -8.1105 × 10 ^-5
C ₁₅ -4.0256 × 10 ^-5
FFS [7]
C ₄ 2.5400 × 10 ^-2 C ₆ -9.4522 × 10 ^-2 C ₈ -1.1009 × 10 ^-2
C ₁₀ -7.0438 × 10 ^-3 C ₁₁ -3.1848 × 10 ^-3 C ₁₃ -7.4213 × 10 ^-3
C ₁₅ 1.1954 × 10 ^-3
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentric (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y (variable) Z 0.70
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y (variable) Z 2.69
α -45.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y (variable) Z 2.69
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 4.53 Z 2.69
α -90.00 β 0.00 γ 0.00
Eccentricity (7)
X 0.00 Y 4.74 Z 2.69
α -90.00 β 0.00 γ -90.00
Eccentricity (8)
X 0.00 Y 11.92 Z 2.69
α -90.00 β 18.46 γ -90.00
Eccentric (9)
X -2.82 Y 8.17 Z 2.69
α -90.00 β 63.92 γ -90.00
Eccentric (10)
X 3.15 Y 8.07 Z 2.69
α 90.00 β 87.84 γ 90.00
Eccentric (11)
X 3.65 Y 8.07 Z 2.69
α 0.00 β -90.00 γ 0.00
Eccentric (12)
X 3.95 Y 8.07 Z 2.69
α 0.00 β -90.00 γ 0.00
Eccentric (13)
X 4.58 Y 8.07 Z 2.69
α 0.00 β -90.00 γ 0.00
(Variable eccentricity)
Object distance infinity 300mm
Eccentricity (3) Y 0.00 -0.11
Eccentricity (4) Y 0.00 -0.11
Eccentricity (5) Y 4.06 3.96.

Example 9
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 3.8mm
Focal length [Y]: 3.8mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.5842 30.5
4 FFS [2] (RE) Eccentricity (4) 1.5842 30.5
5 FFS [3] Eccentricity (5)
6 ∞ (diaphragm surface) Eccentricity (6)
7 FFS [4] Eccentricity (7) 1.5256 56.4
8 FFS [5] (RE) Eccentricity (8) 1.5256 56.4
9 FFS [6] (RE) Eccentricity (9) 1.5256 56.4
10 FFS [7] Eccentricity (10)
11 ∞ Eccentricity (11) 1.5163 64.1
12 ∞ Eccentricity (12)
Image plane ∞ Eccentricity (13)
FFS [1]
C ₄ 2.7963 × 10 ^-2 C ₆ 3.3427 × 10 ^-2 C ₈ -5.1888 × 10 ^-4
C ₁₀ -3.8534 × 10 ^-3 C ₁₁ 8.9830 × 10 ^-4 C ₁₃ 2.2239 × 10 ^-4
C ₁₅ -3.3038 × 10 ^-4
FFS [2]
C ₄ 3.4437 × 10 ^-4 C ₆ 2.4673 × 10 ^-2 C ₈ -2.5128 × 10 ^-4
C ₁₀ 7.5584 × 10 ^-4 C ₁₁ -2.9278 × 10 ^-5 C ₁₃ -8.4864 × 10 ^-5
C ₁₅ -1.6528 × 10 ^-5
FFS [3]
C ₄ -6.8275 × 10 ^-2 C ₆ 5.8499 × 10 ^-2 C ₈ -9.3924 × 10 ^-4
C ₁₀ 7.6517 × 10 ^-3 C ₁₁ -5.0871 × 10 ^-3 C ₁₃ -4.5720 × 10 ^-3
C ₁₅ -2.0754 × 10 ^-4
FFS [4]
C ₄ -4.5663 × 10 ^-3 C ₆ 1.8783 × 10 ^-1 C ₈ -2.2943 × 10 ^-3
C ₁₀ 6.8410 × 10 ^-3 C ₁₁ -3.8661 × 10 ^-4 C ₁₃ -1.6654 × 10 ^-3
C ₁₅ 3.5034 × 10 ^-3
FFS [5]
C ₄ 2.0397 × 10 ^-2 C ₆ 3.1101 × 10 ^-2 C ₈ -7.8656 × 10 ^-4
C ₁₀ 2.0294 × 10 ^-4 C ₁₁ 4.2526 × 10 ^-6 C ₁₃ 2.1295 × 10 ^-5
C ₁₅ 3.1019 × 10 ^-5
FFS [6]
C ₄ -1.7760 × 10 ^-2 C ₆ -1.2882 × 10 ^-2 C ₈ -1.6580 × 10 ^-3
C ₁₀ -6.1565 × 10 ^-4 C ₁₁ -1.4850 × 10 ^-6 C ₁₃ -1.0825 × 10 ^-4
C ₁₅ -1.7420 × 10 ^-5
FFS [7]
C ₄ -1.1625 × 10 ^-2 C ₆ -8.6638 × 10 ^-2 C ₈ -1.0966 × 10 ^-2
C ₁₀ -2.7272 × 10 ^-3 C ₁₁ -2.0328 × 10 ^-3 C ₁₃ -3.4369 × 10 ^-3
C ₁₅ -1.3695 × 10 ^-3
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentric (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y 0.00 Z 0.70
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y 0.00 Z 2.80
α -45.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y 3.41 Z 2.80
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 4.75 Z 2.80
α -90.00 β 0.00 γ 0.00
Eccentricity (7)
X (variable) Y (variable) Z 2.80
α -90.00 β 0.00 γ -90.00
Eccentricity (8)
X (variable) Y (variable) Z 2.80
α -90.00 β 18.37 γ -90.00
Eccentric (9)
X (variable) Y (variable) Z 2.80
α -90.00 β 63.91 γ -90.00
Eccentric (10)
X (variable) Y (variable) Z 2.80
α 90.00 β 87.14 γ 90.00
Eccentric (11)
X 3.56 Y 8.12 Z 2.80
α 0.00 β -90.00 γ 0.00
Eccentric (12)
X 3.86 Y 8.12 Z 2.80
α 0.00 β -90.00 γ 0.00
Eccentric (13)
X 4.48 Y 8.12 Z 2.80
α 0.00 β -90.00 γ 0.00
(Variable eccentricity)
Object distance infinity 100mm
Eccentricity (7) X 0.00 -0.11
Eccentricity (7) Y 4.97 5.26
Eccentric (8) X 0.00 -0.11
Eccentricity (8) Y 11.87 12.16
Eccentric (9) X -2.71 2.82
Eccentric (9) Y 8.24 8.53
Eccentric (10) X 2.98 2.87
Eccentric (10) Y 8.13 8.42.

Example 10
Entrance pupil diameter: 1.27mm
Incident half angle of view [X]: 26.6 °
Incident half angle of view [Y]: 20.6 °
Focal length [X]: 3.9mm
Focal length [Y]: 4.3mm
Surface number Curvature radius Surface spacing Eccentric refractive index Abbe number Object surface ∞ ∞
1 ∞ Eccentricity (1) 1.4950 65.0
2 ∞ Eccentricity (2)
3 FFS [1] Eccentricity (3) 1.5256 56.4
4 FFS [2] (RE) Eccentricity (4) 1.5256 56.4
5 FFS [3] Eccentricity (5)
6 ∞ (diaphragm surface) Eccentricity (6)
7 FFS [4] Eccentricity (7) 1.5256 56.4
8 FFS [5] (RE) Eccentricity (8) 1.5256 56.4
9 FFS [6] Eccentricity (9)
10 ∞ Eccentricity (10) 1.5163 64.1
11 ∞ Eccentricity (11)
Image plane ∞ Eccentricity (12)
FFS [1]
C ₄ 4.4756 × 10 ^-2 C ₆ -3.9937 × 10 ^-2 C ₈ 1.9063 × 10 ^-3
C ₁₀ 9.4431 × 10 ^-3 C ₁₁ -2.3508 × 10 ^-3 C ₁₃ -9.4210 × 10 ^-3
C ₁₅ -7.1779 × 10 ^-3
FFS [2]
C ₄ 3.9507 × 10 ^-5 C ₆ -1.0580 × 10 ^-2 C ₈ 5.2588 × 10 ^-4
C ₁₀ 2.3911 × 10 ^-4 C ₁₁ -2.0456 × 10 ^-5 C ₁₃ -5.9896 × 10 ^-5
C ₁₅ -8.4142 × 10 ^-5
FFS [3]
C ₄ 7.5781 × 10 ^-2 C ₆ 1.2914 × 10 ^-1 C ₈ 1.2875 × 10 ^-3
C ₁₀ -5.0020 × 10 ^-3 C ₁₁ -3.5006 × 10 ^-3 C ₁₃ -4.4055 × 10 ^-3
C ₁₅ -3.5110 × 10 ^-3
FFS [4]
C ₄ -4.9123 × 10 ^-2 C ₆ -1.6509 × 10 ^-2 C ₈ 1.1555 × 10 ^-3
C ₁₀ -2.2120 × 10 ^-2 C ₁₁ -7.1237 × 10 ^-3 C ₁₃ -1.7782 × 10 ^-2
C ₁₅ -2.0575 × 10 ^-3
FFS [5]
C ₄ 4.0778 × 10 ^-3 C ₆ 2.3644 × 10 ^-2 C ₈ 6.0815 × 10 ^-4
C ₁₀ -1.8396 × 10 ^-4 C ₁₁ -5.7542 × 10 ^-4 C ₁₃ -1.1029 × 10 ^-3
C ₁₅ 3.6481 × 10 ^-4
FFS [6]
C ₄ 2.8735 × 10 ^-2 C ₆ 2.1049 × 10 ^-2 C ₈ 2.8137 × 10 ^-3
C ₁₀ 1.9066 × 10 ^-2 C ₁₁ -4.4282 × 10 ^-3 C ₁₃ -7.5164 × 10 ^-3
C ₁₅ 8.9010 × 10 ^-4
Eccentricity (1)
X 0.00 Y 0.00 Z 0.00
α 0.00 β 0.00 γ 0.00
Eccentricity (2)
X 0.00 Y 0.00 Z 0.50
α 0.00 β 0.00 γ 0.00
Eccentricity (3)
X 0.00 Y (variable) Z 0.90
α 0.00 β 0.00 γ 0.00
Eccentricity (4)
X 0.00 Y (variable) Z 3.02
α -45.00 β 0.00 γ 0.00
Eccentricity (5)
X 0.00 Y (variable) Z 3.02
α -90.00 β 0.00 γ 0.00
Eccentricity (6)
X 0.00 Y 2.66 Z 3.02
α -90.00 β 0.00 γ 0.00
Eccentricity (7)
X 0.00 Y 2.86 Z 3.02
α -90.00 β 0.00 γ -90.00
Eccentricity (8)
X 0.00 Y 4.54 Z 3.02
α -90.00 β -46.11 γ -90.00
Eccentric (9)
X 1.98 Y 4.62 Z 3.02
α 90.00 β -84.31 γ 90.00
Eccentricity (10)
X 2.30 Y 4.63 Z 3.02
α 0.00 β -90.00 γ 0.00
Eccentric (11)
X 2.60 Y 4.63 Z 3.02
α 0.00 β -90.00 γ 0.00
Eccentric (12)
X 3.22 Y 4.63 Z 3.02
α 0.00 β -90.00 γ 0.00
(Variable eccentricity)
Object distance infinity 300mm
Eccentricity (3) Y 0.00 -0.07
Eccentricity (4) Y 0.00 -0.07
Eccentric (5) Y 2.06 2.00.

Next, the values of conditional expressions (1) to (4) in the above-described embodiments will be shown.
Conditional Example Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7
(1) 0.01 0.03 0.03 0.00 0.00 0.28 0.00
0.68 0.69 0.69 0.14 0.16 -1.08 0.16
1.46 1.48 1.53 0.83
1.35
(2) 0.00 0.01 0.01 0.00 0.00 0.10 0.00
(3)----0.37 -0.39--0.31
(4) 3 3 3 2 2 4 2

Conditional Example Example 8 Example 9 Example 10
(1) 0.01 0.01 0.00
0.69 0.66 0.17
1.39 1.38
(2) 0.00 0.00 0.00
(3)---0.34
(4) 3 3 2
.

  In the above embodiments, one optical element (eccentric prism) is arranged before and after the stop, but a plurality of optical elements (eccentric prisms) may be arranged on either one or both. When the optical element is a decentered prism, the decentered prism is not limited to a decentered prism having one or two internal reflections as shown in FIGS. For example, various decentered prisms having one or more internal reflections can be used.

  Examples of decentered prisms that can be used as optical elements are shown below. In any case, description will be made assuming that forward ray tracing is performed. That is, the decentering prism P is described as a prism that forms an image of an object located far away on the image plane 136 through the pupil 131. However, these decentered prisms P can also be used as decentered prisms P in which light enters from the image plane 136 side and forms an image on the pupil 131 side.

  In the case of FIG. 38, the decentered prism P includes a first surface 132, a second surface 133, a third surface 134, and a fourth surface 135. The light incident through the entrance pupil 131 is refracted by the first surface 132 and enters the eccentric prism P. The light incident on the decentered prism P is internally reflected by the second surface 133 and internally reflected by the third surface 134 so as to form a Z-shaped optical path. Further, this light enters the fourth surface 135 and is refracted to form an image on the image surface 136.

  In the case of FIG. 39, the decentered prism P includes a first surface 132, a second surface 133, a third surface 134, and a fourth surface 135. The light incident through the entrance pupil 131 is refracted by the first surface 132 and enters the eccentric prism P. The light incident on the decentered prism P is internally reflected by the second surface 133, is incident on the third surface 134, is totally reflected, is incident on the fourth surface 135, and is internally reflected. Further, the light again enters the third surface 134 and is refracted, and forms an image on the image surface 136.

  In the case of FIG. 40, the decentered prism P includes a first surface 132, a second surface 133, a third surface 134, and a fourth surface 135. The light incident through the entrance pupil 131 is refracted by the first surface 132 and enters the eccentric prism P. The light that has entered the eccentric prism P is internally reflected by the second surface 133, is incident on the third surface 134, is internally reflected, and is incident again on the second surface 133 and is internally reflected. Further, this light enters the fourth surface 135 and is refracted to form an image on the image surface 136.

  In the case of FIG. 41, the decentered prism P includes a first surface 132, a second surface 133, a third surface 134, and a fourth surface 135. The light incident through the entrance pupil 131 is refracted by the first surface 132 and enters the eccentric prism P. The light incident on the decentered prism P is internally reflected by the second surface 133 and incident on the third surface 134 and internally reflected. Subsequently, this light is incident again on the second surface 133 and internally reflected, and is incident on the fourth surface 135 and internally reflected. Further, the light is incident again on the second surface 133 and is refracted, and forms an image on the image surface 136.

  In the case of FIG. 42, the decentered prism P includes a first surface 132, a second surface 133, and a third surface 134. The light incident through the entrance pupil 131 is refracted by the first surface 132 and enters the eccentric prism P. The light that has entered the decentered prism P is internally reflected by the second surface 133, is incident again on the first surface 132, and is then totally reflected. Subsequently, this light is internally reflected by the third surface 134, enters the first surface 132 three times, and is totally reflected. Further, this light is incident again on the third surface 134 and is refracted, and forms an image on the image surface 136.

  In the case of FIG. 43, the decentered prism P includes a first surface 132, a second surface 133, and a third surface 134. The light incident through the entrance pupil 131 is refracted by the first surface 132 and enters the eccentric prism P. The light that has entered the decentered prism P is internally reflected by the second surface 133, is incident again on the first surface 132, and is then totally reflected. Subsequently, this light is internally reflected by the third surface 134, enters the first surface 132 three times, and is totally reflected. Further, this light again enters the third surface 134 and is internally reflected, and then enters the first surface 132 four times and is refracted, and forms an image on the image surface 136.

  Furthermore, like the decentered prism 20 in FIG. 44 described later, it may be composed of the first surface 21 to the fourth surface 24 and reflect three times within the prism. Alternatively, like the decentered prism 20 of FIG. 45 described later, the second surface 22 includes the first surface 21 to the third surface 23, and the second surface 22 reflects twice in the prism that serves as both the total reflection surface and the exit surface. It may be a thing. Alternatively, like the decentered prism 20 in FIG. 46 described later, the first surface 21 is composed of the first surface 21 to the third surface 23. The first surface 21 serves as both the incident surface and the total reflection surface, and reflects twice in the prism. You may do. These may be used as an optical element (eccentric prism) in the front group or an optical element (eccentric prism) in the rear group.

  44 to 47 below show examples of the optical system of the present invention in which optical elements (eccentric prisms) are combined differently from those in the first to tenth embodiments. However, numerical data is omitted. Further, the eccentric prism is simply referred to as a prism. 44 to 47, the prism on the image side with respect to the aperture 2 with respect to the prism on the object side with respect to the aperture 2 is originally arranged by rotating approximately 90 ° around the axial principal ray 1. However, for the sake of easy understanding, it is shown in a state where the rotation is not performed.

  In the case of FIG. 44, the prism 10 is the same as that of FIG. The prism 20 includes a first surface 21 to a fourth surface 24 as optical function surfaces. The first surface 21 is a combined surface that serves both as an incident surface and a second reflecting surface, the second surface 22 is a first reflecting surface, the third surface 23 is a third reflecting surface, and the fourth surface 24 is an exit surface. The light that has passed through the prism 10 and the diaphragm 2 passes through the incident surface 21, is reflected by the first reflecting surface 22, and is then totally reflected by the first surface 21. Subsequently, this light is internally reflected by the third reflecting surface 23, passes through the exit surface 24, and forms an image on the image surface 3. In the prism 20, light rays are internally reflected so as to form an M-shaped optical path in the prism.

  In the case of FIG. 45, the prism 10 is the same as in FIG. The prism 20 has a first surface 21 to a third surface 23 as optical function surfaces. The first surface 21 is an incident surface, the second surface 22 is a combined surface that serves as both the first reflecting surface and the exit surface, and the third surface 23 is a second reflecting surface. The light beam that has passed through the prism 10 and the diaphragm 2 passes through the incident surface 21, is totally reflected by the first reflecting surface 22, is internally reflected by the second reflecting surface 23, and is then transmitted through the second surface 22 and then the image surface 3. Image on top.

  In the case of FIG. 46, the prism 10 is the same as that of FIG. The prism 20 has a first surface 21 to a third surface 23 as optical function surfaces. The first surface 21 is a combined surface that serves both as an incident surface and a second reflecting surface, the second surface 22 is a first reflecting surface, and the third surface 23 is an exit surface. The light beam that has passed through the front group prism 10 and the diaphragm 2 is transmitted through the incident surface 21, reflected by the first reflecting surface 22, then totally reflected by the first surface 21, and then transmitted through the exit surface 23 to pass through the image surface 3. Image on top.

  FIG. 47 is a diagram showing a case where the optical system of the present invention is configured. In FIG. 47, one prism 10 is disposed on the front side of the diaphragm 2 and two prisms 20 and 20 ′ are disposed on the rear side of the diaphragm 2. Each of the prisms 10, 20, and 20 'is a prism that performs one reflection within the prism.

  Moreover, in Examples 1-10, although the resin material is used as a material of an optical element, you may use an organic inorganic composite material instead. The organic-inorganic composite usable in the present invention will be described.

  The organic-inorganic composite is a composite in which an organic component and an inorganic component are mixed and combined at a molecular level or nanoscale. Its form is (1) a structure in which a polymer matrix composed of an organic skeleton and a matrix composed of an inorganic skeleton are entangled with each other and penetrated into each other's matrix. There are those in which inorganic fine particles (so-called nanoparticles) sufficiently smaller than the wavelength of light of the scale are uniformly dispersed, and (3) those having a composite structure of these. Some interaction acts between the organic component and the inorganic component, such as intermolecular forces such as hydrogen bonds, dispersion forces, and Coulomb forces, and attractive forces due to covalent bonds, ionic bonds, and π electron cloud interactions. In the organic-inorganic composite, as described above, the organic component and the inorganic component are mixed at a molecular level or a scale region smaller than the wavelength of light. For this reason, there is almost no influence on light scattering, and a transparent body can be obtained. Further, as derived from the Maxwell equation, the material reflects the optical characteristics of the organic component and the inorganic component. Therefore, various optical characteristics (refractive index, wavelength dispersion) are developed according to the types and abundance ratios of the organic component and the inorganic component. Therefore, various optical characteristics can be obtained by blending organic and inorganic components in any ratio.

Table 1 below shows a composition example of an organic-inorganic composite of acrylate resin (ultraviolet curable) and zirconia (ZrO ₂ ) nanoparticles. Table 2 shows a composition example of an organic-inorganic composite of an acrylate resin and zirconia (ZrO ₂ ) / alumina (Al ₂ O ₃ ) nanoparticles. Table 3 shows a composition example of an organic-inorganic composite of acrylate resin and niobium oxide (Nb ₂ O ₅ ) nanoparticles. Table 4 shows a composition example of an organic-inorganic composite of acrylate resin, zirconium alkoxide, and alumina (Al ₂ O ₃ ) nanoparticles.

Table 1
┌────┬────┬────┬┬────┬────┬────┬─────┐
│ zirconia _{│n d │ν d │n C │n F} │n g │ Notes │
│A content│ │ │ │ │ │ │
├────┼────┼────┼┼────┼────┼────┼─────┤
│ 0 │1.49236 │57.85664 │1.48981 │1.49832 │1.50309 │Acrylic │
│ │ │ │ │ │ │ 100% │
├────┼────┼────┼┼────┼────┼────┼─────┤
│ 0.1 │1.579526 │54.85037 │1.57579 │1.586355 │1.59311 │ │
├────┼────┼────┼┼────┼────┼────┼─────┤
│ 0.2 │1.662128 │53.223 │1.657315 │1.669756 │1.678308│ │
├────┼────┼────┼┼────┼────┼────┼─────┤
│ 0.3 │1.740814│52.27971│1.735014│1.749184│1.759385│ │
├────┼────┼────┼┼────┼────┼────┼─────┤
│ 0.4 │1.816094│51.71726│1.809379│1.825159│1.836887│ │
├────┼────┼────┼┼────┼────┼────┼─────┤
│ 0.5 │1.888376 │51.3837 │1.880807 │1.898096 │1.911249│ │
└────┴────┴────┴┴────┴────┴────┴─────┘
.

Table 2
┌───┬───┬────┬────┬────┬────┬┬────┬────┐
_{│AlsO 3 │ZrOs │n d │ν d │n} C │n F │n g │ Notes │
│ presence rate │ presence rate │ │ │ │ │ │
├───┼───┼────┼────┼────┼────┼┼────┼────┤
│0.1 │0.4 │1.831515│53.56672│1.824851│1.840374│1.851956│Acryl│
│ │ │ │ │ │ │ │50% │
├───┼───┼────┼────┼────┼────┼┼────┼────┤
│0.2 │0.3 │1.772832│56.58516│1.767125│1.780783│1.790701│ │
├───┼───┼────┼────┼────┼────┼┼────┼────┤
│0.3 │0.2 │1.712138│60.97687│1.707449│1.719127│1.727275│ │
├───┼───┼────┼────┼────┼────┼┼────┼────┤
│0.4 │0.1 │1.649213│67.85669│1.645609│1.655177│1.661429│ │
├───┼───┼────┼────┼────┼────┼┼────┼────┤
│0.2 │0.2 │1.695632│58.32581│1.690903│1.702829│1.774891│ │
└───┴───┴────┴────┴────┴────┴┴────┴────┘
.

Table 3
┌───┬───┬────┬────┬────┬┬────┬────┐
_{│NbsO 5 │AlsO 3 │n d │ν d} │n C │n F │n g │
│Content│Content│ │ │ │ │ │
├───┼───┼────┼────┼────┼┼────┼────┤
│0.1 │ 0 │1.589861│29.55772│1.584508│1.604464│1.617565│
├───┼───┼────┼────┼────┼┼────┼────┤
│0.2 │ 0 │1.681719 │22.6091 │1.673857 │1.70401 │1.724457│
├───┼───┼────┼────┼────┼┼────┼────┤
│0.3 │ 0 │1.768813 │19.52321 │1.758673 │1.798053 │1.8251 │
├───┼───┼────┼────┼────┼┼────┼────┤
│0.4 │ 0 │1.851815 │17.80818 │1.839583 │1.887415 │1.920475│
├───┼───┼────┼────┼────┼┼────┼────┤
│0.5 │ 0 │1.931253 │16.73291 │1.91708 │1.972734 │2.011334│
└───┴───┴────┴────┴────┴┴────┴────┘
.

Table 4
┌─────┬──────┬────┬────┬┬────┬────┐
￨AlsOc (film) │ zirconia A _{│n d │ν d │n C │n F} │
│Content │Lucoxide │ │ │ │ │
├─────┼──────┼────┼────┼┼────┼────┤
│ 0 │ 0.3 │1.533113│58.39837│1.530205│1.539334│
├─────┼──────┼────┼────┼┼────┼────┤
│ 0.1 │ 0.27 │1.54737 │62.10192│1.544525│1.553339│
├─────┼──────┼────┼────┼┼────┼────┤
│ 0.2 │ 0.24 │1.561498│66.01481│1.558713│1.567219│
├─────┼──────┼────┼────┼┼────┼────┤
│ 0.3 │ 0.21 │1.575498│70.15415│1.572774│1.580977│
├─────┼──────┼────┼────┼┼────┼────┤
│ 0.4 │ 0.18 │1.589376│74.53905│1.586709│1.594616│
└─────┴──────┴────┴────┴┴────┴────┘
.

  Now, an electronic apparatus provided with the optical system of the present invention as described above will be described. A photographing unit is used for this electronic device. In this photographing unit, an object image is formed by the optical system, and photographing is performed by receiving the image on an image sensor such as a CCD or a silver salt film. This imaging unit can also be used as an optical device using a small imaging device, for example, an imaging optical system of an endoscope. Further, this imaging unit can be used as an observation device for observing an object image through an eyepiece, particularly as an imaging optical system of a camera.

  Electronic devices include digital cameras, video cameras, digital video units, personal computers that are examples of information processing devices, mobile computers, telephones, especially mobile phones that are convenient to carry, portable information terminals, and electronic endoscopes. is there. The embodiment is illustrated below.

  48 to 50 are conceptual diagrams of configurations in which the optical system of the present invention is incorporated in the photographing objective optical system of the electronic camera. 48 is a front perspective view showing the appearance of the electronic camera 40, FIG. 49 is a rear perspective view thereof, and FIG. 50 is a cross-sectional view showing the configuration of the electronic camera 40.

  In this example, the electronic camera 40 includes a photographing optical system 41 having a photographing optical path 42, a finder optical system 43 having a finder optical path 44, a shutter 45, a flash 46, a liquid crystal display monitor 47, and the like. In such a configuration, when the user presses the shutter 45 disposed on the upper part of the camera 40, photographing is performed through the photographing objective optical system 48 in conjunction therewith.

  A photographing objective optical system 48 is disposed on the photographing optical path 42. The photographing objective optical system 48 includes a cover glass CG 1, a front group prism 10, an aperture stop 2, and a rear group prism 20. Here, the optical system according to the present invention is used for the optical system from the cover glass CG 1 or the first prism 10 to the second prism 20. The object image formed by the photographic objective optical system 48 is formed on the imaging surface of the CCD 49 through a filter such as a low-pass filter and an infrared cut filter (not shown). The object image received by the CCD 49 is displayed as an electronic image on the liquid crystal display monitor 47 provided on the back of the camera via the processing means 52. In addition, the processing means 52 is provided with a memory or the like, and can record a captured electronic image. This memory may be provided separately from the processing means 52, or may be configured to perform recording and writing electronically using a floppy (registered trademark) disk or the like. Further, it may be configured as a silver salt camera in which a silver salt film is arranged in place of the CCD 49.

  Further, a finder objective optical system 53 is disposed on the finder optical path 44 via a cover member 54. The object image formed on the imaging surface 67 by the finder objective optical system 53 is formed on the field frame 57 of the Porro prism 55 that is an image erecting member. The field frame 57 separates the first reflecting surface 56 and the second reflecting surface 58 of the Porro prism 55 and is disposed therebetween. Behind this polyprism 55 is an eyepiece optical system 59 that guides the erect image to the observer eyeball E.

  In the camera 40 configured in this way, the photographing objective optical system 48 can be made small and thin with a small number of optical members. Therefore, the camera itself can be reduced in size and thickness, and the degree of freedom of arrangement inside the camera is increased, which is advantageous in design.

  Next, FIG. 51 shows a conceptual diagram of another configuration in which the optical system of the present invention is incorporated in the objective optical system 48 of the photographing unit of the electronic camera 40. In this case, an optical system according to the present invention comprising the cover glass CG 1, the front group prism 10, the aperture stop 2, and the rear group prism 20 is used for the photographing objective optical system 48 disposed on the photographing optical path 42. Yes.

  The object image formed by the photographing objective optical system 48 is formed on the imaging surface of the CCD 49 through a filter such as a low-pass filter and an infrared cut filter (not shown). The object image received by the CCD 49 is displayed as an electronic image on a liquid crystal display element (LCD) 60 via the processing means 52. The processing unit 52 also controls the recording unit 61. The recording means 61 is for recording the object image photographed by the CCD 49 as electronic information. The image displayed on the LCD 60 is guided to the observer eyeball E through the eyepiece optical system 59.

  The eyepiece optical system 59 is composed of a decentered prism. In this example, the eyepiece optical system 59 is composed of three surfaces: an incident surface 62, a reflecting surface 63, and a combined reflecting / refracting surface 64. In addition, at least one of the two reflecting surfaces 63 and 64, preferably both surfaces, provides power to the light beam and has a single symmetry plane that corrects decentration aberrations. It consists of a curved surface. In addition, the photographing objective optical system 48 may include other lenses (positive lens, negative lens) as components of the prisms 10 and 20 on the object side, between the prisms, or on the image side.

  In the camera 40 configured in this way, the photographing objective optical system 48 can be made small and thin with a small number of optical members. Therefore, the camera itself can be reduced in size and thickness, and the degree of freedom of arrangement inside the camera is increased, which is advantageous in design.

  Next, FIGS. 52 to 54 are conceptual diagrams showing a configuration in which the optical system of the present invention is built in a personal computer which is an example of an information processing apparatus.

  52 is a front perspective view with the cover of the personal computer 300 opened, FIG. 53 is a side view of the photographing optical system 303 of the personal computer 300, and FIG. 54 is a side view of the state of FIG. As shown in FIGS. 52 to 54, the personal computer 300 includes a keyboard 301, information processing means and recording means, a monitor 302, and a photographing optical system 303.

  Here, the keyboard 301 is used for a writer to input information from the outside. Further, the information processing means and recording means are not shown. The monitor 302 is for displaying information to the operator. The monitor 302 may be a transmissive liquid crystal display element that is illuminated from the back by a backlight (not shown), a reflective liquid crystal display element that reflects and displays light from the front, a CRT display, or the like. The photographing optical system 303 is for photographing an image of the operator himself or a surrounding area. Note that the photographic optical system 303 is built in the upper right of the monitor 302 in the figure, but is not limited to that location. The photographing optical system 303 may be anywhere around the monitor 302 or the keyboard 301, for example.

  The photographing optical system 303 has an objective optical system 100 including the optical system of the present invention and an image sensor chip 162 that receives an image on a photographing optical path 304. These are built in the personal computer 300. The object image received by the image sensor chip 162 is input to the processing means of the personal computer 300 through the terminal and is displayed on the monitor 302 as an electronic image. In FIG. An image 305 is shown. Further, this image 305 can be transmitted to the outside through the processing means. Therefore, it can be transmitted to a communication partner at a remote place via the Internet or a telephone. As a result, the image 305 can be displayed on the personal computer of the communication partner.

  Next, as another example of the information processing apparatus, FIG. 29 shows an example in which the optical system of the present invention is incorporated in a telephone, in particular, a mobile phone that is convenient to carry.

  55A is a front view of the mobile phone 400, FIG. 55B is a side view, and FIG. 55C is a cross-sectional view of the photographing optical system 405. As shown in FIGS. 55A to 55C, the mobile phone 400 includes a microphone unit 401, a speaker unit 402, an input dial 403, a monitor 404, a photographing optical system 405, an antenna 406, and processing. Means (not shown).

  Here, the microphone unit 401 is for inputting an operator's voice as information. The speaker unit 402 is for outputting the voice of the other party. An input dial 403 is used by an operator to input information. The monitor 404 is for displaying information such as a photographed image of the operator himself or the other party, a telephone number, and the like. The monitor 404 is a liquid crystal display element. The antenna 406 is for transmitting and receiving communication radio waves. The processing means is for processing image information, communication information, input signals, and the like. In the drawing, the arrangement positions of the respective components are not particularly limited to these.

  The photographing optical system 405 includes an objective optical system 100 including the optical system of the present invention and an image sensor chip 162 that receives an image. Here, the objective optical system 100 uses the optical system of the present invention and is disposed on the photographing optical path 407. These are built in the mobile phone 400. The object image received by the image sensor chip 162 is input to a processing unit (not shown) via a terminal, and is displayed as an electronic image on the monitor 404, the monitor of the communication partner, or both. Further, when transmitting an image to a communication partner, the processing means includes a signal processing function for converting information of an object image received by the image sensor chip 162 into a signal that can be transmitted.

  Next, FIG. 56 shows a conceptual diagram of a configuration in which the optical system according to the present invention is incorporated in the objective optical system 82 of the observation system of the electronic endoscope.

  As shown in FIG. 56A, the electronic endoscope includes an electronic endoscope 71, a light source device 72 that supplies illumination light, a video processor 73, a monitor 74, a VTR deck 75, and a video. The disk 76, a video printer 77, and a head-mounted image display device (HMD) 78 are configured. Here, the video processor 73 is for performing signal processing corresponding to the electronic endoscope 71. The monitor 74 is for displaying a video signal output from the video processor 73. The VTR deck 75 and the video disc 76 are connected to the video processor 73 and are used for recording video signals and the like. The video printer 77 is for printing out a video signal as a video.

  The distal end portion 80 of the insertion portion 79 of the electronic endoscope 71 and the eyepiece portion 81 thereof are configured as shown in FIG. The light beam illuminated from the light source device 72 passes through the light guide fiber bundle 88 and illuminates the observation site by the illumination objective optical system 89. And the light from this observation site | part is formed as an object image by the objective optical system 82 for observation which consists of an optical system of this invention through cover glass CG1. This object image is formed on the imaging surface of the CCD 84 through a filter such as a low-pass filter or an infrared cut filter (not shown). Further, the object image is converted into a video signal by the CCD 84, and the video signal is directly displayed on the monitor 74 by the video processor 73 shown in FIG.

  The video signal is recorded in the VTR deck 75 and the video disc 76. Alternatively, the image is printed out from the video printer 77 as an image. The video signal is displayed on the image display element of the HMD 78 and displayed to the wearer of the HMD 78. At the same time, the video signal converted by the CCD 84 is displayed on the liquid crystal display element (LCD) 86 of the eyepiece 81 as an electronic image. The display image is guided to the observer eyeball E through the eyepiece optical system 87.

  The endoscope configured as described above can be configured with a small number of optical members, and can realize high performance and low cost.

  The optical system of the present invention can also be used as a projection optical system. FIG. 57 shows a conceptual diagram of a presentation system in which a personal computer 90 and a liquid crystal projector 91 are combined. In FIG. 57, the optical system according to the present invention is used for the projection optical system 96 of the liquid crystal projector 91. In this example, the optical system according to the present invention including the first prism 10, the aperture stop 2, and the second prism 20 is used for the projection optical system 96. In FIG. 57, the prism 20 on the projection side with respect to the aperture 2 is essentially rotated about 90 ° around the axial principal ray 1 with respect to the prism 10 on the liquid crystal panel (LCP) 93 side with respect to the aperture 2. However, for the sake of clarity, the rotation is not shown. Therefore, originally, the screen 97 is disposed substantially in front of or behind the plane of the drawing.

  In FIG. 57, the image / original data created on the personal computer 90 is branched from the monitor output and output to the processing control unit 98 of the liquid crystal projector 91. In the processing control unit 98 of the liquid crystal projector 91, the input data is processed and output to the liquid crystal panel (LCP) 93. On the liquid crystal panel 93, an image corresponding to the input image data is displayed. The light from the light source 92 is transmitted through the field lens 95 disposed immediately before the liquid crystal panel 93 after the transmission amount is determined by the gradation of the image displayed on the liquid crystal panel 93, and constitutes the optical system of the present invention. The light is projected onto a screen 97 via a projection optical system 96 including a first prism 10, an aperture stop 2, a second prism 20, and a positive lens cover lens 94.

  The projector configured as described above can be configured with a small number of optical members, can achieve high performance and low cost, and can be downsized.

  The above optical system of the present invention and electronic equipment using the same can be configured as follows, for example.

[1] A stop, at least one object-side reflecting surface disposed on the object side from the stop and inclined from the optical axis, and at least one image-side reflecting surface disposed on the image side from the stop and inclined from the optical axis In an optical system having at least an image sensor,
Rays from the center of the object through the center of the aperture to the center of the image are axial principal rays, and for the reflective surfaces tilted from all the optical axes in the optical system, the incident side axial principal rays and the reflective side axes for each reflective surface When the plane defined by the upper principal ray is the reference surface of each reflecting surface,
At least one reference surface of the object side reflection surface and at least one reference surface of the image side reflection surface intersect at an arbitrary angle,
An optical system, wherein at least one object-side reflecting surface and at least one image-side reflecting surface have a rotationally asymmetric aspherical shape.

    [2] When the intersecting line between the reflecting surface and its reference surface is the intersecting line of each reflecting surface, all the reflecting surfaces having a rotationally asymmetric aspheric shape in the reflecting surface have the following conditional expression: 2. The optical system as described in 1 above, wherein

−5 <Rry / Rrx <5 (1)
Where Rry: the radius of curvature of each reflecting surface in the direction of intersection,
Rrx: radius of curvature of each reflecting surface in the direction perpendicular to the intersecting direction,
It is.

    [3] When an intersection line between the reflection surface and its reference surface is an intersection line of each reflection surface, the reflection surface arranged closest to the object side has a rotationally asymmetric aspherical shape, and the most object side 3. The optical system as described in 1 or 2 above, wherein the reflecting surface arranged in (1) satisfies the following conditional expression.

−0.5 <1 / (Rr1x · P1y) <0.5 (2)
Where Rr1x: a radius of curvature in a direction perpendicular to the intersecting direction of the reflecting surface disposed on the most object side,
P1y: the power of the entire system in the direction of the intersection of the reflecting surfaces arranged on the most object side,
It is.

    [4] When the line of intersection between the reflecting surface and its reference surface is the line of intersection of each reflecting surface, it has at least one rotationally asymmetric aspherical refractive surface, and the rotationally asymmetrical aspherical refractive surface If the object side refractive surface is the object side refractive surface and the intersection line between the object side refractive surface and the reference surface of the most object side reflective surface is the object side refractive surface intersection line, the object side refractive surface is The optical system according to any one of 1 to 3, wherein the following conditional expression is satisfied.

-3 <1 / (Rt1y · Py) <0 (3)
Where Rt1y: radius of curvature of the object-side refracting surface in the direction of intersection with the object-side refracting surface,
P2y: the power of the entire system in the direction of the object-side refracting plane intersecting line,
It is.

    [5] The optical system as set forth in any one of [1] to [4], wherein all the reflecting surfaces and refracting surfaces have a rotationally asymmetric aspherical shape.

    [6] Any one of 1 to 5 above, wherein the at least one optical element arranged on the object side of the stop has at least one reflecting surface and at least two refracting surfaces. The optical system according to 1.

    [7] Any one of 1 to 6 above, wherein the at least one optical element disposed on the image side from the stop has at least one reflecting surface and at least two refracting surfaces. The optical system according to 1.

    [8] The optical system as described in 6 or 7 above, wherein focusing is performed by moving at least one of the optical elements.

    [9] The optical system according to any one of 1 to 8, wherein focusing is performed by moving at least the image sensor.

    [10] The optical system according to any one of [1] to [9], wherein the diaphragm is disposed substantially perpendicular to an imaging surface of the imaging device.

    [11] The optical system as set forth in any one of [1] to [10], wherein a normal vector of an image pickup surface of the image pickup device is substantially perpendicular to an incident light vector of the optical system.

    [12] Among the reflecting surfaces, the light beam reflected on the intersection line between the object-side reflecting surface arranged closest to the object side and the reference surface of the object-side reflecting surface is in the direction of the substantially short side of the image sensor. The light bundle that forms an image and is reflected on the intersection line between the image-side reflection surface arranged closest to the image side and the reference surface of the image-side reflection surface in the reflection surface is substantially in the direction of the long side of the image sensor. 12. The optical system according to any one of 1 to 11, wherein the optical system is arranged so as to form an image.

    [13] The optical system as described in any one of 1 to 12 above, wherein the total number of reflections satisfies the following conditional expression.

2 ≦ R _all ≦ 4 (4)
Where R _{all is the} total number of reflections,
It is.

    [14] The optical system as set forth in any one of [1] to [13], wherein a light shielding member is provided between the reflecting surfaces.

[15] The optical system as described in 14 above, wherein the light shielding member is formed integrally with the stop. [16] The optical system as set forth in any one of 1 to 15, wherein the optical system has at least one lens. The optical system according to item.

    [17] The optical system as described in 16 above, wherein at least one of the lenses is disposed on the image side with respect to all the reflecting surfaces.

    [18] The optical system as described in 16 or 17 above, wherein focusing is performed by moving at least one of the lenses.

    [19] The optical system as described in 16 above, wherein at least one lens is attached closer to the object side than all the reflecting surfaces during photographing.

    [20] The optical system as described in 19 above, wherein a zooming effect is obtained by attaching the lens.

    [21] The optical system as described in any one of 1 to 20 above, wherein an organic-inorganic composite material is used as an optical material of at least one optical element constituting the optical system.

    [22] The optical system as described in 21 above, wherein the organic-inorganic composite contains zirconia nanoparticles.

    [23] The optical system as described in 21 above, wherein the organic-inorganic composite includes zirconia and alumina nanoparticles.

    [24] The optical system as described in 21 above, wherein the organic-inorganic composite includes niobium oxide nanoparticles.

    [25] The optical system as described in 21 above, wherein the organic-inorganic composite contains a hydrolyzate of zirconium alkoxide and nanoparticles of alumina.

    [26] An electronic apparatus comprising: the optical system according to any one of 1 to 25 above; and an imaging device arranged on the image side thereof.

    [27] The electronic apparatus as set forth in [26], further comprising means for electrically correcting the shape of an image formed by the optical system.

    [28] The electronic device as described in 27 above, wherein the correction uses different parameters for each wavelength region.

    [29] In an electronic device comprising the optical system according to any one of 16 to 20 above and an image sensor disposed on the image side, the lens is housed in the electronic device when not in use. An electronic device characterized by

It is a figure for demonstrating the light beam which enters into the aspherical reflective surface of eccentric arrangement | positioning, a meridian direction, and a sphere direction. It is sectional drawing in alignment with the optical axis which shows arrangement | positioning and an optical path of the optical system based on Example 1 of this invention, (a) is YZ sectional drawing along an optical axis, (b) is AA in (a). 'Cross section. It is the same figure as FIG. 2 which shows arrangement | positioning and optical path of the optical system which concerns on Example 2 of this invention. It is a figure similar to FIG. 2 which shows arrangement | positioning and an optical path of the optical system based on Example 3 of this invention. FIG. 7 is a view similar to FIG. 2 showing the arrangement and optical path of an optical system according to Example 4 of the present invention. FIG. 10 is a view similar to FIG. 2 showing the arrangement and optical path of an optical system according to Example 5 of the present invention. It is a figure similar to FIG. 2 which shows arrangement | positioning and an optical path of the optical system based on Example 6 of this invention. It is a figure similar to FIG. 2 which shows arrangement | positioning and an optical path of the optical system based on Example 7 of this invention. It is a figure similar to FIG. 2 which shows arrangement | positioning and an optical path of the optical system based on Example 8 of this invention. It is a figure similar to FIG. 2 which shows arrangement | positioning and an optical path of the optical system based on Example 9 of this invention. It is a figure similar to FIG. 2 which shows arrangement | positioning and an optical path of the optical system based on Example 10 of this invention. 2 is a part of a lateral aberration diagram of the optical system of Example 1. FIG. FIG. 4 is the remaining part of the lateral aberration diagram of the optical system of Example 1. FIG. 4 is a part of a lateral aberration diagram of the optical system of Example 2. FIG. FIG. 6 is the remaining part of the lateral aberration diagram of the optical system of Example 2. FIG. FIG. 4 is a part of a lateral aberration diagram of the optical system according to Example 3. FIG. 6B is a remaining portion of a lateral aberration diagram of the optical system of Example 3. FIG. FIG. 6 is a part of a lateral aberration diagram of the optical system according to Example 4. FIG. 10B is a remaining portion of a lateral aberration diagram of the optical system of Example 4. FIG. FIG. 10 is a part of a lateral aberration diagram of the optical system according to Example 5. FIG. 10B is a remaining portion of a lateral aberration diagram of the optical system of Example 5. FIG. 10 is a part of a lateral aberration diagram of the optical system according to Example 6. FIG. FIG. 10B is a remaining portion of a lateral aberration diagram of the optical system according to Example 6. 10 is a part of a lateral aberration diagram of the optical system according to Example 7. FIG. FIG. 10B is a remaining portion of a lateral aberration diagram of the optical system according to Example 7. 10 is a part of a lateral aberration diagram when the optical system of Example 8 is focused at infinity. FIG. FIG. 10B is a remaining portion of a lateral aberration diagram when the optical system of Example 8 is focused at infinity. FIG. 10 is a part of a lateral aberration diagram when the optical system of Example 8 is in close focus. FIG. 10B is a remaining portion of a lateral aberration diagram when the optical system according to Example 8 is in close focus. 10 is a part of a lateral aberration diagram when the optical system of Example 9 is focused at infinity. FIG. FIG. 10B is a remaining portion of a lateral aberration diagram when the optical system of Example 9 is focused on infinity. 10 is a part of a lateral aberration diagram when the optical system according to Example 9 is in close focus. FIG. 10B is a remaining portion of a lateral aberration diagram when the optical system according to Example 9 is in close focus. FIG. 14 is a part of a lateral aberration diagram of the optical system of Example 10 when focusing on infinity. FIG. 10B is a remaining portion of a lateral aberration diagram when the optical system of Example 10 is focused on infinity. FIG. 12 is a part of a lateral aberration diagram when the optical system according to Example 10 is in close focus. FIG. 11B is a remaining portion of a lateral aberration diagram when the optical system according to Example 10 is in close focus. It is a figure which shows another modification of an eccentric prism. It is a figure which shows another modification of an eccentric prism. It is a figure which shows another modification of an eccentric prism. It is a figure which shows another modification of an eccentric prism. It is a figure which shows another modification of an eccentric prism. It is a figure which shows another modification of an eccentric prism. It is a figure which shows another example of the optical system of this invention which consists of a combination of a prism different from Examples 1-10. It is a figure which shows another example of the optical system of this invention which consists of a combination of a prism different from Examples 1-10. It is a figure which shows another example of the optical system of this invention which consists of a combination of a prism different from Examples 1-10. It is a figure which shows another example of the optical system of this invention which consists of a combination of a prism different from Examples 1-10. It is a front perspective view which shows the external appearance of the electronic camera to which the optical system of this invention is applied. FIG. 49 is a rear perspective view of the electronic camera of FIG. 48. It is sectional drawing which shows the structure of the electronic camera of FIG. It is a conceptual diagram of another electronic camera to which the optical system of the present invention is applied. It is the front perspective view which opened the cover of the personal computer in which the optical system of this invention was integrated as an objective optical system. It is sectional drawing of the imaging optical system of a personal computer. It is a side view of the state of FIG. FIG. 2 is a front view (a), a side view (b), and a sectional view (c) of the photographing optical system of a mobile phone in which the optical system of the present invention is incorporated as an objective optical system. FIG. 2 is a system configuration diagram (a) of an electronic endoscope to which the optical system of the present invention is applied and a conceptual diagram (b) of the optical system. It is a conceptual diagram of the presentation system to which the optical system of the present invention is applied.

Explanation of symbols

CG1 ... cover glass CG1a ... first surface CG1b of cover glass ... second surface CG2 of cover glass ... cover glass CG2a ... first surface CG2b of cover glass ... second surface E of cover glass ... observer eyeball P ... eccentric prism 1 ... Axial principal ray 2 ... Aperture stop 3 ... Image plane 10 ... Optical element (eccentric prism, front group prism)
11: Optical function surface (first surface)
12: Optical function surface (second surface)
13. Optical function surface (third surface)
14: Optical function surface (fourth surface)
20. Optical element (eccentric prism, rear group prism)
20 '... optical element (eccentric prism)
21: Optical functional surface (first surface)
22: Optical functional surface (second surface)
23: Optical function surface (third surface)
24: Optical function surface (fourth surface)
40 ... electronic camera 41 ... imaging optical system 42 ... imaging optical path 43 ... finder optical system 44 ... finder optical path 45 ... shutter 46 ... flash 47 ... liquid crystal display monitor 48 ... imaging objective optical system 49 ... CCD
52 ... Processing means 53 ... Finder objective optical system 54 ... Cover member 55 ... Porro prism 56 ... First reflecting surface 57 ... Field frame 58 ... Second reflecting surface 59 ... Eyepiece optical system 67 ... Imaging surface 60 ... Liquid crystal display element (LCD)
61 ... Recording means 62 ... incident surface 63 ... reflective surface 64 ... reflective and refracting surface 71 ... electronic endoscope 72 ... light source device 73 ... video processor 74 ... monitor 75 ... VTR deck 76 ... video disc 77 ... video printer 78 ... Head-mounted image display device (HMD)
79 ... Insertion part 80 ... Tip part 81 ... Eyepiece part 82 ... Observation objective optical system 84 ... CCD
86 ... Liquid crystal display (LCD)
87 ... Eyepiece optical system 88 ... Light guide fiber bundle 89 ... Illumination objective optical system 90 ... Personal computer 91 ... Liquid crystal projector 92 ... Light source 93 ... LCP (liquid crystal panel)
94 ... Cover lens 95 ... Field lens 96 ... Projection optical system 97 ... Screen 98 ... Processing control unit 100 ... Objective optical system 131 ... Entrance pupil 132 ... First surface 133 ... Second surface 134 ... Third surface 135 ... Fourth surface 136 ... Image plane 162 ... Image sensor chip 300 ... Personal computer 301 ... Keyboard 302 ... Monitor 303 ... Shooting optical system 304 ... Shooting optical path 305 ... Image 400 ... Mobile phone 401 ... Microphone unit 402 ... Speaker unit 403 ... Input dial 404 ... Monitor 405 ... Optical system 406 ... Antenna 407 ... Optical optical path

Claims (2)

An aperture, at least one object-side reflecting surface disposed on the object side from the aperture and inclined from the optical axis, at least one image-side reflecting surface disposed on the image side from the aperture and inclined from the optical axis, and imaging In an optical system having at least an element,
Rays from the center of the object through the center of the aperture to the center of the image are axial principal rays, and for the reflective surfaces tilted from all the optical axes in the optical system, the incident side axial principal rays and the reflective side axes for each reflective surface When the plane defined by the upper principal ray is the reference surface of each reflecting surface,
At least one reference surface of the object side reflection surface and at least one reference surface of the image side reflection surface intersect at an arbitrary angle,
An optical system, wherein at least one object-side reflecting surface and at least one image-side reflecting surface have a rotationally asymmetric aspherical shape. An electronic apparatus comprising: the optical system according to claim 1; and an image pickup device disposed on an image side thereof.

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