JP2002318351A - Image formation optical system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image formation optical system of a finder optical system or the like of a camera by which a clear image is formed in a wide viewing angle and also which is made very small in a size and is made very light in weight. SOLUTION: This image formation optical system DS possesses a diaphragm D and forms an object image, and possesses at least four surfaces in which at least two surfaces are a surface having a finite radius of curvature, and incorporates an eccentric optical device in which a space constituted of a first surface that is a refraction surface, a second surface that is an eccentric reflection surface having positive power, a third surface that is an eccentric reflection surface and a fourth surface that is a refraction surface is filled with a medium whose refractive index is >=1, and two reflection surfaces are disposed so that a main light beam reaching the object image from the diaphragm D is not crossed at the inside of the eccentric optical device, and also the object image is formed as a primary image without having an image surface at an inside thereof.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an imaging optical system, and more particularly to an imaging optical system such as a finder optical system of a camera.

[0002]

2. Description of the Related Art Conventionally, a well-known head or face-mounted image display device is disclosed in Japanese Patent Application Laid-Open No. 3-101709. This is because the entire optical system is shown in FIG.
As shown in FIG. 0 (b), the display image of the image display element is transmitted as an aerial image by a relay optical system including a positive lens, and the aerial image is transmitted by an ocular optical system including a concave reflecting mirror. Is enlarged and projected into the eyeball of the observer.

Another conventional type is disclosed in US Pat. No. 4,669,810. As shown in FIG. 31, this apparatus forms an intermediate image from a CRT image via a relay optical system, and projects the intermediate image on an observer's eye by a combiner having a reflective holographic element and a hologram surface.

Another conventional image display device is disclosed in Japanese Patent Application Laid-Open No. 62-214782. In this apparatus, as shown in FIG. 32, an image display element is magnified by an eyepiece so that it can be directly observed.

Further, another conventional image display device is disclosed in US Pat. No. 4,026,641. In this apparatus, as shown in FIG. 33, an image of an image display element is transmitted to a curved object surface by a transmission element, and the object surface is projected onto the air by a toric reflection surface.

Another conventional type of image display device is disclosed in Japanese Patent Application Laid-Open No. Hei 6-242393. In this apparatus, as shown in FIG. 34, a light beam from a display source is reflected by a first reflecting mirror and a second reflecting mirror, respectively, and follows an optical path in the shape of a letter “4” to reach an eyeball of an observer. It was done.

[0007]

However, FIG.
0, in the image display device of the type that relays the image of the image display element as shown in FIG. 31, regardless of the type of the eyepiece optical system, it is necessary to use several lenses as a relay optical system in addition to the eyepiece optical system, The optical path length is long, the optical system is large, and the weight is heavy.

In the case of FIG. 30 (b) using only the eyepiece optical system of FIG. 30 (a), only the reflecting surface with the concave surface facing the observer has positive power. As shown, the negative curvature of field greatly occurs.

Further, in the layout as shown in FIG. 32, the projection amount of the device from the face of the observer becomes large. Further, the image display element and the illumination optical system will be attached to the protruding portion, and the device will become larger and heavier.

[0010] The head mounted image display device is a human body,
In particular, because the device is mounted on the head, if the amount of the device protruding from the face is large, the distance from the point supported by the head to the center of gravity of the device is long, and the balance at the time of mounting is poor,
Fatigue increases. In addition, when the device is mounted, moved, rotated, or the like, the device may hit an object.
That is, it is important that the head-mounted image display device is small and lightweight. A major factor that determines the size and weight of this device is the configuration of the optical system.

However, if only a normal magnifying glass is used as the eyepiece optical system, the generated aberration is very large, and there is no means for correcting it. By making the concave surface of the magnifying mirror aspherical, even if spherical aberration is corrected to some extent, coma aberration and curvature of field remain, so if the observation angle of view is increased, it can be a practical device. Absent. Alternatively, when only a concave mirror is used as the eyepiece optical system, not only a normal optical element (a lens or a mirror) but also a transfer element (see FIG. 33) having a surface curved in accordance with the generated field curvature, as shown in FIG. A means of compensating for this with a fiber plate) must be used.

Further, when two reflecting mirrors are arranged as shown in FIG. 34, similarly, correction is made on another surface in order to project onto the eyeball of the observer only with the positive power of the second reflecting mirror. Large negative curvature of field, which is difficult to perform, occurs in the eyepiece optical system.

The present invention has been made in view of the above-mentioned problems of the prior art, and has as its object to provide a camera which is capable of clearly forming an image at a wide angle of view and which is very small and lightweight. An object of the present invention is to provide an imaging optical system such as a finder optical system.

[0014]

According to a first aspect of the present invention, there is provided an imaging optical system for forming an object image, wherein the imaging optical system has at least four surfaces. And a positive power that is decentered with respect to the optical axis in opposition to the first surface and the first surface in the order in which light rays pass according to ray tracing from the stop to the object image. A second surface which is a reflecting surface, a third surface which is opposed to the second surface and is decentered with respect to an optical axis after reflection by the second surface, and a refraction which is closest to the object image. When the fourth surface is a surface, among the at least four surfaces,
At least two surfaces are surfaces having a finite radius of curvature, and a space formed by the first surface to the fourth surface includes an eccentric optical element in which a medium having a refractive index greater than 1 is filled, and The above-mentioned 2 is used so that the principal ray up to the object image does not cross inside the decentered optical element.
And two reflecting surfaces are provided so that the object image is formed as a primary image without having an image plane inside the decentered optical element.

According to another aspect of the present invention, there is provided an image forming optical system having a stop and forming an object image, wherein the image forming optical system has at least four surfaces, and these surfaces are
A first surface, which is a refraction surface, and a second reflection surface, which has a positive power and is decentered with respect to an optical axis, is opposed to the first surface in the order in which light rays pass according to ray tracing from the stop to the object image. A third surface which is a reflecting surface facing the second surface and eccentric with respect to the optical axis after being reflected by the second surface, and a fourth surface which is a refracting surface closest to the object image. In this case, at least two of the at least four surfaces are surfaces having a finite radius of curvature, and a space formed by the first to fourth surfaces is filled with a medium having a refractive index greater than 1. And an at least one optical surface having a refracting action is disposed in an optical path from the stop to the object image.

[0016]

The operation of the image forming optical system according to the present invention will be described below based on an image display device. In the following description, for convenience in design of an optical system, the light ray tracing is performed by tracing light rays from the pupil position of the observer to the image display element.

In the present invention, the first surface of the eyepiece optical system,
The space formed by the second surface, the third surface and the fourth surface is filled with a medium having a refractive index larger than 1, and further, among the four surfaces,
By making the two surfaces have a finite radius of curvature, it becomes possible to correct spherical aberration and coma generated on the eccentric and inclined second surface, and curvature of field, and to achieve a wide exit pupil diameter and It has succeeded in providing a clear observation image having a wide observation angle of view to the observer.

In general, in a concave mirror, by giving a strong power to the concave surface, the Petzval sum becomes large and a positive curvature of field is generated. Also, strong inner coma aberration occurs. In the present invention, the space formed by the first surface, the second surface, the third surface, and the fourth surface is filled with a medium having a refractive index larger than 1, and two of the four surfaces have a finite curvature. By doing so, the aberration generated on the second surface has been successfully corrected.

When the first surface has a finite radius of curvature in addition to the second surface, the height of light rays incident on the second surface is reduced by utilizing the refraction of light rays on the first surface. Becomes possible. By this action, the occurrence of strong internal coma generated by the concave mirror on the second surface can be made relatively small.

In the case where the third surface has a finite radius of curvature in addition to the second surface, the third surface is an effective means for correcting coma aberration and curvature of field generated on the second surface.

In the case where the fourth surface has a finite radius of curvature in addition to the second surface, the fourth surface is given a negative power to correct particularly the curvature of field generated on the second surface. It becomes possible.

Further, the apparatus is provided with two reflecting surfaces, a second surface and a third surface, so that the principal ray from the observer's eyeball to the image display element does not cross inside the eyepiece optical system. The effect of reducing the overall size can be obtained. In particular, when aiming for a wide angle of view, the two reflecting surfaces of the second surface and the third surface are arranged almost in parallel, so that the element can be made thinner and lighter than when the principal ray intersects inside. Can be realized.

Further, the observation image of the image display device is formed as an intermediate image by the relay optical system, and a real image is formed in the air, and the image display device is enlarged and observed as it is, instead of being enlarged and projected on the eyeball by the eyepiece optical system. By projecting the image on the eyeball of the observer, the observer can observe the enlarged image of the image display device as a virtual image, so that the optical system can be configured with a small number of optical elements. In addition, since the constituent optical elements are arranged in such a manner that the second surface, which is the reflection surface of the eyepiece optical system, follows the curve of the face immediately before the face of the observer, the amount of projection from the face can be extremely small. Thus, a small and lightweight image display device can be realized.

It is effective for aberration correction that the third surface is a reflecting surface with the convex surface facing the second surface. Since the second surface is a reflective surface having the main positive power of the entire eyepiece optical system, in addition to the above-described coma aberration, a large curvature of field also occurs. By making the third surface a surface with negative power,
A coma aberration opposite to the inner coma aberration generated on the second surface can be generated on this surface to correct the coma aberration.
Further, the positive curvature of field generated on the second surface is
The negative curvature of field is generated on the surface, and the curvature of field can be corrected at the same time.

The first, second, and third surfaces of the eyepiece optical system
It is effective for aberration correction that any one of the surface and the fourth surface is an eccentric aspheric surface.

This is an important condition for correcting coma aberration, particularly higher-order coma aberration and coma flare, generated on the second surface which is arranged to be decentered in the Y direction or inclined from the visual axis in a coordinate system described later. It is.

As in the present invention, in an image display apparatus using an eyepiece optical system of a type having a reflecting surface decentered or inclined forward of the observer's eyeball, light rays incident on the reflecting surface even when viewed by the observer. Are inclined, so that coma aberration occurs. This coma aberration increases as the angle of inclination of the reflecting surface increases.

However, in order to realize a small-sized image display device having a wide angle of view, unless the amount of eccentricity or the inclination angle is increased to some extent, the image display element and the optical path interfere with each other.
It becomes difficult to secure an observation image with a wide angle of view. For this reason, as the size of the image display device becomes smaller with a wider angle of view, the angle of inclination of the reflecting surface becomes larger, and how to correct the occurrence of higher-order coma aberration becomes an important issue.

In order to correct such complicated coma, any one of the first, second, third, and fourth surfaces constituting the eyepiece optical system is made to be an aspherical surface decentered, so that the optical system can be corrected. Power can be asymmetrical with respect to the visual axis, and the effect of the aspherical surface can be used off-axis, making it possible to effectively correct coma including on-axis Becomes

In the present invention, the observer's visual axis is defined as the Z axis whose direction from the origin toward the eyepiece optical system is positive, one axis orthogonal to the observer's visual axis is defined as the Y axis, and the Z axis and the Y axis. Assuming that another axis orthogonal to the X axis is R _y2 , the radius of curvature of the second surface in the YZ plane is R _y2 , and the radius of curvature of the third surface in the YZ plane is R _y3 , 0 <R It is useful to satisfy _y3 / _Ry2 <4 (1).

The above equation (1) is an effective condition for correcting coma aberration, particularly higher-order coma aberration and coma flare, which occurs on the second surface arranged eccentrically or inclined in the Y direction.
When the inclination angle of the second surface, which is the reflecting surface, and the amount of eccentricity in the Y direction are large, it is important to satisfy this condition.

As described above, in an image display apparatus using an eyepiece optical system of the type having a reflection surface inclined forward of the observer's eyeball as in the present invention, if a small image display apparatus with a wide angle of view is used, The angle of inclination of the reflecting surface increases as much as possible, and how to correct the occurrence of high-order coma aberration is an important issue. Since the second surface is a reflective surface having the main positive power of the entire eyepiece optical system, correction of aberrations generated on this surface is performed on the third surface, which is a reflective surface whose power can be similarly larger than that of the refractive surface. Doing it works effectively. In this case, it is important that the power ratio between the second surface and the third surface satisfies the condition of Expression (1). When the value exceeds the upper limit of 4 in the expression (1), the power of the third surface becomes small, so that the above-mentioned correction effect cannot be sufficiently obtained.

It is important that any one of the first, second, third and fourth surfaces of the eyepiece optical system is an anamorphic surface. That is, the radius of curvature in the YZ plane,
This is a surface having a different radius of curvature in an XZ plane orthogonal to this surface.

This condition is a condition for correcting aberration caused by the eccentricity or inclination of the second surface with respect to the visual axis. In general, when the spherical surface is decentered, the light rays incident on the surface have different curvatures with respect to the light rays in the plane of incidence and in the plane perpendicular to the plane of incidence. For this reason, as in the present invention, in the eyepiece optical system in which the reflection surface is disposed eccentrically or inclined with respect to the visual axis in front of the observer's eyeball, the observation image on the visual axis corresponding to the center of the observation image also has the above-described reason. Astigmatism occurs. In order to correct this axial astigmatism, the radius of curvature of any one of the first, second, third, and fourth surfaces of the eyepiece optical system is perpendicular to the entrance plane. It is important to be different in the plane.

Further, the radius of curvature of the second surface in the YZ plane is R _y2 , and the radius of curvature of the second surface in the XZ plane is R _y2 .
_{When x2} , it is important that _Ry2 / _Rx2 > 1 (2) is satisfied.

Equation (2) is a condition for correcting aberrations caused by the second surface being inclined with respect to the visual axis, in particular, astigmatism including on-axis. In general, as the angle of view increases, higher-order astigmatism appears. In a convex lens system, the meridional image increases in the negative direction as the angle of view increases, and the spherical missing image increases in the positive direction. In order to correct these astigmatisms, it is necessary to configure the optical system such that the power in the meridional plane is reduced and the power in the spherical plane is increased. Therefore, it is necessary to increase the radius of curvature on one surface in the Y direction and decrease in the X direction.

In the eyepiece optical system of the present invention, since the surface having the main positive power is the second reflecting surface, the other surface has the Y surface.
By making the second surface satisfy the condition (2), the effect of astigmatism correction can be increased more than by providing a difference between the radius of curvature in the -Z plane and the radius of curvature in the XZ plane. Can be provided, which is more preferable for aberration correction.

It is desirable that either one of the first and fourth surfaces of the eyepiece optical system be tilted or decentered with respect to the visual axis. By tilting or decentering any one of the first surface and the fourth surface, it is possible to correct a coma aberration generated asymmetrically between the image on the image display element side and the image on the opposite side with respect to the visual axis. In addition, the surface on which the image display element is disposed can be disposed substantially perpendicular to the optical axis after reflection on the second surface. This is effective when using an image display element having poor viewing angle characteristics.

In the present invention, when the angle between the second surface of the eyepiece optical system and the visual axis is α, it is desirable that 30 ° <α <80 ° (3).

This is a condition for preventing the image display device of the present invention from interfering with the observer's head. If the lower limit of 30 ° in the expression (3) is exceeded, the reflected light beam is 90 ° with respect to the visual axis.
Due to having the above-mentioned reflection angle, the imaging positions of off-axis rays above and below the screen are very far apart, which is not realistic. Conversely, if the angle exceeds the upper limit of 80 °, the light reflected on the second surface returns to the face as it is, so that the image display device and the face interfere.

It is important that the display surface of the image display element is disposed so as to be inclined with respect to the visual axis. When the refraction surface or the reflection surface constituting the optical element is decentered or inclined, the ray from the pupil has a refraction angle or a reflection angle at the refraction surface or the reflection surface which differs depending on the image height, and the image surface is inclined with respect to the visual axis. Sometimes. In this case, by arranging the image display element surface so as to be inclined with respect to the visual axis, the inclination of the image plane can be corrected.

By the way, the smaller the size of the image display device is, the wider the angle of view is, the larger the inclination angle of the second surface, which is the first reflecting surface, is, and the more occurrence of high-order coma aberration is increased. In addition, since astigmatism caused by the inclination of the surface also increases, the surface has at least four surfaces, and the surfaces are refraction surfaces in the order in which light rays pass according to the reverse ray tracing from the observer's eyeball to the image display element. A first surface, a second reflecting surface having a positive power which is opposite to the first surface and eccentric to the observer's visual axis;
A third surface which is opposite to the second surface and is eccentric with respect to the observer's visual axis after reflection at the second surface, and a fourth surface which is a refraction surface closest to the image display element. In this case, at least two of the at least four surfaces are surfaces having a finite radius of curvature, and the eccentricity is such that a space formed by the first to fourth surfaces is filled with a medium having a refractive index greater than 1. Only with the optical element, it may be difficult to sufficiently correct these aberrations.

For this reason, by disposing at least one optical surface having a refracting action between the observer's eyeball and the image display element in addition to the above-described decentered optical element, the aberration generated in the eyepiece optical system can be corrected. Can be performed more effectively.

In the decentered optical element of the present invention, the second surface and the third
Since the surfaces are reflection surfaces, no chromatic aberration occurs on those surfaces. In addition, since the principal ray on the fourth surface near the image display element is substantially parallel to the optical axis, chromatic aberration is less generated. Therefore, the chromatic aberration of the eyepiece optical system is dominated by the occurrence of chromatic aberration on the first surface. In an optical system having a wide angle of view as in the present invention, lateral chromatic aberration appears more remarkably than axial chromatic aberration.

That is, it is important to correct the chromatic aberration of magnification occurring on the first surface, and a clearer and higher-resolution image can be displayed. For this purpose, as the configuration of the eyepiece optical system, two types of optical elements constituting the eyepiece optical system are provided by disposing an eccentric optical element and at least one optical surface having a refractive action between the observer's eyeball and the image display element. The above media can be used, and chromatic aberration of magnification can be corrected by the difference in Abbe number of those media.

As described above, in the eyepiece optical system of the present invention, it is important to correct chromatic aberration generated on the first surface of the decentered optical element. This is made possible by configuring the at least one optical surface with a surface that generates an inverse chromatic aberration substantially equal to the amount of chromatic aberration generated on the first surface.

Hereinafter, correction of chromatic aberration will be described in detail. By disposing the decentered optical element and at least one optical surface having a refracting action in the optical path from the image display element to the observer's eyeball, it is possible to configure the medium of the eyepiece optical system with two or more. In this case, the chromatic aberration of magnification can be corrected by changing the Abbe number of the medium.
For example, consider a case where a negative refractive lens different from the medium of the decentered optical element is bonded to the first surface of the decentered optical element. The overall focal length f, the focal length of the decentered optical system, the Abbe number is f ₁ , ν ₁ , the focal length of the refractive lens, the Abbe number is f ₂ ,
Assuming that ν ₂ , the achromatic condition of the entire optical system is given by the following equation.

F ₁ = (ν ₁ −ν ₂ ) · f / ν ₁ f ₂ = − (ν ₁ −ν ₂ ) · f / ν ₂ 1 / f = 1 / f ₁ + 1 / f ₂ Focal length f and focal length f of the decentered optical element
_{Since 1} is positive and the focal length f ₂ of the refractive lens is negative, the relationship between the decentered optical system and the Abbe number of the refractive lens is ν ₁ >
ν ₂ . In other words, by using a medium having a smaller Abbe number as the refractive lens in this case, it is possible to satisfactorily correct chromatic aberration.

When at least one optical surface exists in a place other than the above, the Abbe number of each medium can be set in the same manner according to the above-described example.

When at least one optical surface having a positive refractive power is provided between the decentered optical element and the observer's eyeball, the light beam diameter on the second surface of the decentered optical element becomes small, so that a higher order The occurrence of coma is reduced, and the image can be clearly observed up to the periphery of the image display screen. In addition, since the chief ray around the image is refracted by at least one optical surface having a positive refractive power, the height of a ray incident on the decentered optical element can be reduced. It is possible to set the observation angle of view even larger.

When the at least one optical surface is disposed between the second surface and the third surface of the decentered optical element, the light beam reflected by the second surface is refracted by the at least one optical surface. Since the ray height on the third surface is low, it is difficult for the off-axis light beam passing through the first surface and the off-axis light beam reflected on the third surface to interfere with each other.

When the at least one optical surface is disposed between the fourth surface of the decentered optical element and the image display element, when the optical element has a negative power, it is located closest to the image display element. Therefore, it is possible to correct the field curvature generated by the decentered optical element.

By disposing the at least one optical surface eccentrically with respect to the visual axis, coma aberration asymmetrically generated between the image on the image display element side and the image on the opposite side with respect to the visual axis. Is corrected, and the optical axis with respect to the surface on which the image display element is arranged can be made substantially perpendicular.

Further, by forming at least one optical surface with a cemented lens, it is possible to correct chromatic aberration of magnification occurring on at least one optical surface, and it is effective in securing a clear and wide angle of view. It is.

Further, an air lens is formed by forming at least one optical surface and each surface of the decentered optical element into a concave surface facing each other. In this case, since the negative power of the two surfaces can be effectively used, the Petzval sum of the entire optical system can be reduced, and the correction of the curvature of field generated on the second surface of the eccentric optical element is effectively performed. be able to.

Further, by having means for positioning the image display element and the eyepiece optical system with respect to the observer's head,
The observer can observe a stable observation image.

Further, the image display device and the eyepiece optical system are provided with support means for supporting the observer's head. It is possible to observe the image in the direction.

Further, the provision of the supporting means for supporting at least two sets of the image display devices at a constant interval enables the observer to easily observe the image with both the left and right eyes. Further, it is possible to enjoy a stereoscopic image by displaying images with parallax on the left and right image display surfaces and observing them with both eyes.

The image display device of the present invention can be used as an image forming optical system such as a finder optical system by forming an image at an object at infinity by using an image display element surface of an eyepiece optical system as an image surface. Becomes possible.

[0060]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments 1 to 17 of the image display apparatus of the present invention will be described below with reference to FIGS. 1 to 17, which are cross-sectional views of respective monocular optical systems.

The configuration parameters of each embodiment will be described later.
In the following description, the surface number is shown as a surface number for reverse tracking from the pupil position 1 of the observer to the image display element 7. Then, as shown in FIG. 1, the coordinates are taken as a Z-axis with the iris position 1 of the observer as the origin and a observer's visual axis 2 as a positive direction from the origin toward the eyepiece optical system. X axis perpendicular to 2 and positive from bottom to top in the vertical direction when viewed from the observer's eyeball; X axis perpendicular to the observer's visual axis 2 and positive from right to left in the horizontal direction as viewed from the observer's eyeball Is defined. That is, the inside of the paper is defined as the YZ plane, and the plane perpendicular to the paper is defined as X-
Let it be the Z plane. It is assumed that the optical axis is bent in the YZ plane of the drawing.

In the configuration parameters described later, the plane spacing, the eccentric amounts Y and Z, and the inclination angle θ differ in the way of setting a reference in each embodiment. Therefore, these will be described for each of the following embodiments. . Note that the tilt angle θ is positive in a counterclockwise direction.

In all the embodiments, the amount of eccentricity Y, Z of the image display element 7 is determined by the distance Y from the center of the pupil 1 of the observer.
Is the distance eccentric in the axis and Z-axis directions, and its inclination angle θ
Is the angle of inclination from the visual axis (Z axis).

In each surface, the non-rotationally symmetric aspherical shape is represented by R _y and R _x on the coordinates defining the surface, where R _y and R _x are the paraxial radius of curvature in the YZ plane (paper plane), X− paraxial curvature in the Z plane radius, K _x, K _y each X-Z plane, Y-
The conic coefficients AR and BR in the Z plane are the fourth-order and sixth-order aspherical coefficients rotationally symmetric with respect to the Z axis, respectively, and AP and BP are the fourth-order and sixth-order non-spherical coefficients rotationally asymmetrical with respect to the Z axis, respectively. Assuming a spherical coefficient, the aspherical expression is as shown below.

Z = [(X ² / R _x ) + (Y ² / R _y )] / [1+
｛1- (1 + K _x ) (X ² / R _x ² )-(1 + K _y ) (Y ² / R _y ² )｝
^{1/2] + AR [(1-} AP) X 2 + (1 + AP) Y 2] 2 + B
The R [(1-BP) X 2 + (1 + BP) Y 2] 3, rotationally symmetric aspherical shape, R is a paraxial curvature radius, K
Is a conical coefficient, A, respectively B 4, sixth order aspheric coefficient, h is When ^{h 2 = X 2 + Y 2} , aspheric expression are as follows.

Z = (h ² / R) / [1+ ｛1- (1 + K) (h ² /
R ² )｝ ^1/2 ] + Ah ² + Bh ⁶ The refractive index of the medium between the surfaces is represented by the d-line refractive index. The unit of the length is mm.

The following embodiments are all image display apparatuses for the right eye, and all the optical elements constituting the image display apparatus for the left eye are Y-color.
This can be realized by symmetrically disposing them on the Z plane.

In an actual apparatus, it is needless to say that the direction in which the optical axis is bent by the eyepiece optical system may be in any direction above, below, or beside the observer.

In each of the cross-sectional views, 1 is the observer pupil position, 2 is the observer's visual axis, and 3 is the first eyepiece optical system.
4 is a second surface of the eyepiece optical system, and 5 is a fourth surface of the eyepiece optical system.
Reference numeral 6 denotes a fourth surface of the eyepiece optical system, 7 denotes an image display element, 9 denotes an eccentric optical system, 10 denotes an optical surface, 11 denotes a negative lens, 12 denotes a positive lens, 13 denotes a cemented lens, and 14 denotes a back mirror. .

The actual ray path in each embodiment is as follows, taking the first embodiment as an example. That is, the light beam emitted from the image display element 7 is refracted by the fourth surface 6 of the eyepiece optical system (eccentric optical system) and enters the eyepiece optical system, and the third surface 5, the second surface 4, and the first surface The light is reflected, reflected, and refracted in the order of the surface 3 and is projected into the eyeball of the observer as the exit pupil 1 at the iris position of the observer's pupil or the center of rotation of the eyeball. Example 1 In this example, a cross section is shown in FIG. 1, but the horizontal angle of view is 30 °, the vertical angle of view is 22.7 °, and the pupil diameter is 4 mm.

In the configuration parameters to be described later, the two surfaces are given an interval, and are the distance from the center of one surface (pupil 1) to the top of the surface in the direction along the visual axis 2. The three sides
The interval and the tilt angle θ are given, the interval is a distance from the top of the two surfaces in the direction along the visual axis 2 to the top of the surface, and the tilt angle θ is the inclination from the visual axis 2. The four planes are given an interval, an eccentric amount Y in the Y direction, and an inclination angle θ. The interval is a distance from the top of the three surfaces in the direction along the visual axis 2 to the top of the surface. , The eccentric distance of the vertex in the Y-axis direction from the visual axis 2, and the tilt angle θ is the tilt from the visual axis 2. The five planes are the interval, the eccentric amount Y in the Y direction, and the inclination angle θ.
The distance is the distance from the top of the four surfaces in the direction along the visual axis 2 to the top of the surface, and the amount of eccentricity Y is
Is the eccentric distance of the top of the surface in the Y-axis direction from, and the tilt angle θ is the tilt from the visual axis 2.

In this embodiment, two, four, and five surfaces are spherical, and three are anamorphic aspheric surfaces. Example 2 In this example, a cross section is shown in FIG. 2, but the horizontal angle of view is 40 °, the vertical angle of view is 30.5 °, and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval, an eccentric amount Y in the Y direction, and an inclination angle θ are given to the two surfaces, and the interval is set in the direction along the visual axis from the center of one surface (pupil 1). Is the distance from the visual axis 2 to the eccentricity of the vertex in the Y-axis direction, and the inclination angle θ is the inclination from the visual axis 2. The third, fourth, and fifth planes respectively have an eccentricity Y in the Y-axis direction and an eccentricity Z in the Z-axis direction.
And the inclination angle θ, the eccentricity Y is the distance of the eccentricity of the surface top in the Y-axis direction from the visual axis 2, and the eccentricity Z is the distance from the two surface vertices in the Z-axis direction. Is the eccentric distance of the top of the plane, and the inclination angle θ is the inclination from the visual axis 2.

In this embodiment, the two surfaces are spherical,
Surfaces 3, 4, and 5 are anamorphic aspheric surfaces. Embodiment 3 A cross section of this embodiment is shown in FIG. 3, but has a horizontal angle of view of 30 °, a vertical angle of view of 22.7 °, and a pupil diameter of 4 mm.

The configuration parameters to be described later are the same as in the first embodiment.

In this embodiment, the two surfaces are flat,
Four and five surfaces are spherical, and three are anamorphic aspheric surfaces. Embodiment 4 In this embodiment, a cross section is shown in FIG. 4. The horizontal angle of view is 30 °, the vertical angle of view is 22.7 °, and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval is given between the two surfaces, and the distance is the distance from the center of one surface (pupil 1) to the top of the surface in the direction along the visual axis 2. The three sides
The interval, the amount of eccentricity Y, and the inclination angle θ are given.
The eccentricity Y is the distance from the vertex of two surfaces in the direction along the visual axis 2 to the vertex thereof, and the eccentricity Y is the distance of the eccentricity of the vertex from the visual axis 2 in the Y-axis direction, and the inclination angle θ Is the inclination from the visual axis 2. The four planes are given an interval, an eccentric amount Y in the Y direction, and an inclination angle θ. The interval is a distance from the top of the three surfaces in the direction along the visual axis 2 to the top of the surface. , The eccentric distance of the vertex in the Y-axis direction from the visual axis 2, and the tilt angle θ is the tilt from the visual axis 2. The five planes are given an interval, an eccentric amount Y in the Y direction, and an inclination angle θ, and the interval is a distance from the top of the four surfaces in the direction along the visual axis 2 to the top of the surface. Is the eccentric distance of the vertex in the Y-axis direction from the visual axis 2, and the inclination angle θ is
It is the inclination from.

In this embodiment, the second and fifth surfaces are spherical, and the third and fourth surfaces are anamorphic aspheric surfaces. Embodiment 5 In this embodiment, a cross section is shown in FIG. 5, and the horizontal angle of view is 30 °, the vertical angle of view is 22.7 °, and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval and an inclination angle θ are given to the two surfaces, and the interval is a distance from the center of one surface (pupil 1) to the top of the surface in the direction along the visual axis 2. The tilt angle θ is a tilt from the visual axis 2. 3
The planes are spaced, are distances along the central axis of the two planes, and are coaxial with the two planes. The four planes are given an interval, an eccentric amount Y in the Y direction, and an inclination angle θ.
The eccentricity Y is the distance to the top of the surface in the direction along the central axis of the surface, and the amount of eccentricity Y in the direction perpendicular to the central axes of the two surfaces (the coordinates are rotated by the inclination angle θ on the two surfaces). The eccentric distance of the surface top, and the inclination angle θ is the inclination from the central axis of the two surfaces. The five planes are the interval, the eccentric amount Y in the Y direction, and the inclination angle θ.
The distance is a distance from the top of the four surfaces in the direction along the central axis of the two surfaces to the top of the surface, and the amount of eccentricity Y is
The eccentric distance of the top of the surface in a direction perpendicular to the central axes of the two surfaces, and the inclination angle θ is the inclination from the central axes of the two surfaces. The six planes are given an eccentricity Y in the Y direction and a tilt angle θ, and the eccentricity Y is the distance of the eccentricity of the vertices from the top of the five faces in a direction perpendicular to the central axis of the two faces. And the tilt angle θ is a tilt from the central axis of the two surfaces.

In this embodiment, the second, third and sixth surfaces are spherical, and the fourth and fifth surfaces are anamorphic aspherical surfaces. A negative lens 11 composed of two spherical optical surfaces 10 is eccentrically joined to the first surface 3 of the decentered optical element 9 with respect to the visual axis 2. Embodiment 6 In this embodiment, a cross section is shown in FIG. 6, but the horizontal angle of view is 30 °, the vertical angle of view is 22.7 °, and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval, an eccentric amount Y in the Y direction, and an inclination angle θ are given to the two surfaces, and the interval is defined as the direction along the visual axis 2 from the center of one surface (pupil 1). The eccentricity Y is the distance from the visual axis 2 to the eccentricity of the vertex in the Y-axis direction, and the tilt angle θ is the tilt from the visual axis 2. The three planes are given a distance, are distances along the central axis of the two planes, and
It is coaxial with two surfaces. The four planes are given an interval, an eccentric amount Y in the Y direction and an inclination angle θ, the interval is a distance to the surface top in a direction along the central axis of the three surfaces, and the eccentric amount Y is two surfaces. Is the eccentric distance of the top of the surface in a direction perpendicular to the central axis of the surface (assuming that the coordinates are rotated by the inclination angle θ on the two surfaces), and the inclination angle θ is the inclination from the central axis of the two surfaces. is there. 5
The eccentric amount Y in the Y direction, the eccentric amount Z in the Z direction, and the tilt angle θ are given to the surfaces 6, 6, and 7, respectively.
The eccentricity of the top of the surface in a direction perpendicular to the central axis of the four surfaces (assuming that the coordinates are further rotated by the inclination angle θ on the four surfaces). The eccentric distance of the surface top from the surface top of the four surfaces along the direction, and the inclination angle θ is the inclination of the four surfaces from the central axis.

In this embodiment, two, three, four,
The seventh surface is a spherical surface, and the fifth and sixth surfaces are anamorphic aspheric surfaces. In addition, the negative lens 11 composed of two optical surfaces 10 which are spherical surfaces is used for the observer's pupil 1 and the first decentered optical element 9.
It is arranged eccentrically with respect to the visual axis 2 between itself and the surface 3. Embodiment 7 In this embodiment, a cross section is shown in FIG. 7, and the horizontal view angle is 30 °, the vertical view angle is 22.7 °, and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval, an eccentric amount Y in the Y direction, and an inclination angle θ are given to the two surfaces, and the interval is defined as the direction along the visual axis 2 from the center of one surface (pupil 1). The eccentricity Y is the distance from the visual axis 2 to the eccentricity of the vertex in the Y-axis direction, and the tilt angle θ is the tilt from the visual axis 2. The three surfaces and the four surfaces are provided with an interval, and each two surfaces along the central axis of the two surfaces.
Plane, distance from three planes, and all are coaxial with two planes. The fifth, sixth, seventh, and eighth surfaces are given an eccentric amount Y in the Y direction, an eccentric amount Z in the Z direction, and an inclination angle θ, respectively, and the eccentric amount Y is in the Y-axis direction from the visual axis 2. Is the eccentric distance of the top of the surface, and the amount of eccentricity Z is Z
The eccentric distance of the vertex in the axial direction, and the inclination angle θ is the inclination from the visual axis 2.

In this embodiment, two, three, four,
The fifth and eighth surfaces are spherical surfaces, and the sixth and seventh surfaces are anamorphic aspheric surfaces. Further, a cemented lens 13 having negative power and constituted by three optical surfaces 10 which are spherical surfaces is arranged eccentrically with respect to the visual axis 2 between the pupil 1 of the observer and the eccentric optical element 9. Example 8 This example shows a cross section in FIG. 8, but has a horizontal angle of view of 30 °, a vertical angle of view of 22.7 °, and a pupil diameter of 4 mm.

In the configuration parameters described later, the two planes are given an interval, and are the distance from the center of one plane (pupil 1) to the top of the plane in the direction along the visual axis 2. 3 sides, 4
The eccentric amount Y in the Y direction, the eccentric amount Z in the Z direction, and the inclination angle θ are given to the surfaces 5, 5, 6, and 7, respectively. Is the eccentric distance of the vertex of the surface, the amount of eccentricity Z is the distance of the vertex of the surface from the vertex of the two surfaces in the Z-axis direction, and the inclination angle θ is the inclination from the visual axis 2. is there.

In this embodiment, two, three, five,
Seven surfaces are spherical surfaces, and four and six surfaces are anamorphic aspheric surfaces. Further, one optical surface 10 having a spherical surface and a concave surface facing the pupil 1 is disposed between the first surface 3 and the second surface 4 of the decentered optical element 9 so as to be eccentric with respect to the visual axis 2. Embodiment 9 In this embodiment, a cross section is shown in FIG. 9. The horizontal angle of view is 30 °, the vertical angle of view is 22.7 °, and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval, an eccentric amount Y in the Y direction, and an inclination angle θ are given to the two surfaces, and the interval is defined as the direction along the visual axis 2 from the center of one surface (pupil 1). The eccentricity Y is the distance from the visual axis 2 to the eccentricity of the vertex in the Y-axis direction, and the tilt angle θ is the tilt from the visual axis 2. 3, 4, 5
The plane 6, the plane 7, the plane 7, the plane 8, the plane 9 and the plane 9 are given an eccentric amount Y in the Y direction, an eccentric amount Z in the Z direction and an inclination angle θ, respectively.
The amount of eccentricity Y is the eccentric distance of the vertex from the visual axis 2 in the Y-axis direction, and the amount of eccentricity Z is the eccentric distance of the vertex from the vertex of the two surfaces in the Z-axis direction. Yes, tilt angle θ
Is the inclination from the visual axis 2.

In this embodiment, three, four, six,
Surfaces 7 and 9 are spherical surfaces, surface 2 is a rotationally symmetric aspherical surface, and surfaces 5 and 8 are anamorphic aspherical surfaces. Also,
Two optical surfaces 10 each having a spherical surface with the convex surface facing the pupil 1 are:
The eccentric optical element 9 is disposed eccentrically with respect to the visual axis 2 between the first surface 3 and the second surface 4. Example 10 In this example, a cross section is shown in FIG.
The vertical angle of view is 22.7 ° and the pupil diameter is 4 mm.

The configuration parameters described later are the same as in the ninth embodiment.

In this embodiment, three, four, six,
Surfaces 7 and 9 are spherical surfaces, surface 2 is a rotationally symmetric aspherical surface, and surfaces 5 and 8 are anamorphic aspherical surfaces. Also,
An optical surface 10 having a spherical surface with a concave surface facing the pupil 1 and a back mirror 14 having an anamorphic aspheric surface with a concave surface facing the pupil 1 are formed, and the second surface of the decentered optical element 9 is opposite to the pupil 1. Are arranged eccentrically with respect to the visual axis 2. However, in this embodiment, the second surface 14 of the decentered optical element 9 is substantially constituted by the reflection surface of the back mirror 14. Embodiment 11 In this embodiment, a cross section is shown in FIG.
The vertical angle of view is 22.7 °, and the pupil diameter is 8 mm.

In the configuration parameters to be described later, an interval, an eccentric amount Y in the Y direction, and an inclination angle θ are given to the two surfaces, and the interval is defined as a direction along the visual axis 2 from the center of one surface (pupil 1). The eccentricity Y is the distance from the visual axis 2 to the eccentricity of the vertex in the Y-axis direction, and the tilt angle θ is the tilt from the visual axis 2. 3, 4, 5
The eccentric amount Y in the Y direction, the eccentric amount Z in the Z direction, and the tilt angle θ are given to the surfaces 6, 6, and 7, respectively.
The amount of eccentricity Y is the distance of the eccentricity of the top of the surface in a direction perpendicular to the central axis of the two surfaces (assuming that the coordinates are rotated by the inclination angle θ on the two surfaces). Is the eccentric distance of the top of the two surfaces from the top of the two surfaces in the direction along the central axis, and the inclination angle θ is the inclination of the two surfaces from the central axis.

In this embodiment, two, four, five,
Six and seven surfaces are spherical surfaces, and three surfaces are anamorphic aspheric surfaces. In addition, one optical surface 10 having a spherical surface with the convex surface facing the pupil 1 is arranged eccentrically with respect to the visual axis 2 between the second surface 4 and the third surface 5 of the eccentric optical element 9. Example 12 In this example, a cross section is shown in FIG.
The vertical angle of view is 22.7 °, and the pupil diameter is 8 mm.

The configuration parameters described later are the same as in the eleventh embodiment.

In this embodiment, two, four, five,
Six and seven surfaces are spherical surfaces, and three surfaces are anamorphic aspheric surfaces. In addition, one optical surface 10 having a spherical surface with the convex surface facing the pupil 1 is arranged eccentrically with respect to the visual axis 2 between the second surface 4 and the third surface 5 of the eccentric optical element 9. Further, although the three and five constituent parameters of the constituent parameters are the reflecting surfaces, each of them has a configuration in which total reflection can be used. Embodiment 13 In this embodiment, a cross section is shown in FIG.
The vertical angle of view is 22.7 ° and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval and a tilt angle θ are given to the two surfaces, and the interval is a distance from the center of one surface (pupil 1) to the top of the surface in the direction along the visual axis 2. The tilt angle θ is a tilt from the visual axis 2. 3
The surface is given an interval, an eccentric amount Y in the Y direction and an inclination angle θ, and the interval is a distance from the top of the two surfaces in the direction along the central axis of the two surfaces to the top of the surface. Is the eccentric distance of the top of the surface in the direction perpendicular to the central axes of the two surfaces (assuming that the coordinates are rotated by the inclination angle θ on the two surfaces), and the inclination angle θ is the central axis of the two surfaces It is the inclination from. The four planes are given an interval, an eccentric amount Y in the Y direction, and an inclination angle θ, and the interval is a distance from the top of the three surfaces in the direction along the central axis of the two surfaces to the top of the surface. Y is the eccentric distance of the top of the two planes in the direction perpendicular to the central axis, and the inclination angle θ is
This is the inclination from the central axis of the two surfaces. The five planes are given an interval, an eccentric amount Y in the Y direction, and a tilt angle θ, and the interval is a distance from the top of the four surfaces in the direction along the central axis of the two surfaces to the top of the four planes. Y is the eccentric distance of the top of the surface in the direction perpendicular to the central axes of the two surfaces, and the inclination angle θ is the inclination from the central axes of the two surfaces. The six surfaces are spaced, are along the central axis of the five surfaces, and are coaxial with the five surfaces.

In this embodiment, the second, fifth and sixth surfaces are spherical, and the third and fourth surfaces are anamorphic aspheric surfaces. In addition, a negative lens 11 composed of two spherical optical surfaces 10 is eccentrically joined to the fourth surface 6 of the decentered optical element 9 with respect to the visual axis 2. Embodiment 14 In this embodiment, a cross section is shown in FIG.
The vertical angle of view is 26.6 ° and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval and an inclination angle θ are given to the two surfaces, and the interval is a distance from the center of one surface (pupil 1) to the top of the surface in the direction along the visual axis 2. The tilt angle θ is a tilt from the visual axis 2. 3
, 4, 5, and 6 are eccentric amounts Y in the Y-axis direction, respectively.
, The eccentric amount Z in the Z-axis direction and the inclination angle θ, the eccentric amount Y is the distance of the eccentricity of the vertex from the visual axis 2 in the Y-axis direction, and the eccentric amount Z is Z The eccentric distance of the surface top from the two surface tops in the axial direction, and the inclination angle θ is
This is the inclination from the visual axis 2. The seven surfaces are spaced apart, are along the central axis of the six surfaces, and are coaxial with the six surfaces.

In this embodiment, two, five, six,
Seven surfaces are spherical surfaces, and three and four surfaces are anamorphic aspheric surfaces. Further, a negative lens 11 composed of two spherical optical surfaces 10 is arranged eccentrically with respect to the visual axis 2 between the fourth surface 6 of the eccentric optical element 9 and the image display element 7. Embodiment 15 In this embodiment, a cross section is shown in FIG.
The vertical angle of view is 22.7 ° and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval, an eccentric amount Y in the Y direction, and an inclination angle θ are given to the two surfaces, and the interval is defined as the direction along the visual axis 2 from the center of one surface (pupil 1). The eccentricity Y is the distance from the visual axis 2 to the eccentricity of the vertex in the Y-axis direction, and the tilt angle θ is the tilt from the visual axis 2. The three planes are given a distance, are distances along the central axis of the two planes, and
It is coaxial with two surfaces. The four planes are given an interval, an eccentric amount Y in the Y direction and an inclination angle θ, the interval is a distance to the surface top in a direction along the central axis of the three surfaces, and the eccentric amount Y is two surfaces. Is the eccentric distance of the top of the surface in a direction perpendicular to the central axis of the surface (assuming that the coordinates are rotated by the inclination angle θ on the two surfaces), and the inclination angle θ is the inclination from the central axis of the two surfaces. is there. The five planes are given an interval, an eccentric amount Y in the Y direction, and a tilt angle θ, and the interval is a distance from the top of the four surfaces in the direction along the central axis of the two surfaces to the top of the four planes. Y is the eccentric distance of the top of the surface in the direction perpendicular to the central axes of the two surfaces, and the inclination angle θ is the inclination from the central axes of the two surfaces. The six planes are given an eccentricity Y in the Y direction and an inclination angle θ.
Is the eccentric distance of the vertices of the five faces in the direction perpendicular to the central axes of the two faces, and the tilt angle θ is the tilt from the central axes of the two faces. The seven surfaces are spaced apart, are along the central axis of the six surfaces, and are coaxial with the six surfaces.

In this embodiment, two, three, six,
Seven surfaces are spherical surfaces, and four and five surfaces are anamorphic aspheric surfaces. The positive lens 12 composed of two spherical optical surfaces 10 is the first surface 3 of the decentered optical element 9, and the negative lens 11 composed of two spherical optical surfaces 10 is the decentered optical element 9. The fourth surface 6 is joined eccentrically to the visual axis 2. Example 16 In this example, a cross section is shown in FIG.
The vertical angle of view is 30.6 ° and the pupil diameter is 4 mm.

In the configuration parameters to be described later, an interval, an eccentric amount Y in the Y direction, and an inclination angle θ are given to the two surfaces, and the interval is defined as the direction along the visual axis 2 from the center of one surface (pupil 1). The eccentricity Y is the distance from the visual axis 2 to the eccentricity of the vertex in the Y-axis direction, and the tilt angle θ is the tilt from the visual axis 2. The three surfaces are given a distance, are distances from the two surfaces along the central axis of the two surfaces, and are coaxial with the two surfaces. The fourth, fifth, sixth, and seventh surfaces respectively have an eccentric amount Y in the Y direction, an eccentric amount Z in the Z direction, and an inclination angle θ.
Is given, and the amount of eccentricity Y is the distance of the eccentricity of the vertex from the visual axis 2 in the Y-axis direction, and the amount of eccentricity Z is
The eccentric distance of the top of the surface in the Z-axis direction from the center of one surface, and the inclination angle θ is the inclination from the visual axis 2.

In this embodiment, two, three, four,
The seventh surface is a spherical surface, and the fifth and sixth surfaces are anamorphic aspheric surfaces. Further, a positive lens 12 composed of two optical surfaces 10 that are an aspheric surface and a spherical surface is disposed eccentrically with respect to the visual axis 2 between the observer's pupil 1 and the first surface 3 of the eccentric optical element 9. I have. Example 17 In this example, a cross section is shown in FIG.
The vertical angle of view is 22.7 °, and the pupil diameter is 8 mm.

In the configuration parameters to be described later, the two surfaces are given an interval, and are the distance from the center of one surface (pupil 1) to the top of the surface in the direction along the visual axis 2. 3 sides, 4
The plane 5, the plane 6, and the plane 6 are given an eccentric amount Y in the Y-axis direction, an eccentric amount Z in the Z-axis direction, and an inclination angle θ, respectively.
Is the eccentric distance of the vertex from the visual axis 2 in the Y-axis direction, and the eccentricity Z is the eccentric distance of the vertex from the two vertex in the Z-axis direction. Angle θ is visual axis 2
It is the inclination from.

In this embodiment, two, three, four,
Six and seven surfaces are spherical, and five are anamorphic aspheric surfaces. Further, the optical surface 10 which is a spherical surface is
Are arranged eccentrically with respect to the visual axis 2 between the second surface 4 and the third surface 5.

Next, the configuration parameters of the first to seventeenth embodiments will be described.

Example 1 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 １ (pupil) 32.000 2 97.497 18.000 1.5163 64.15 3 _Ry- 136.507 -16.000 1.5163 64.15 R _x -110.230 θ 31.00 ° _{K y -8.368527 K x -4.172733 AR -1.59481} × 10 -7 BR 2.66293 × 10 -20 AP 0.21126 BP 2.19465 × 10 3 4 -207.825 13.000 1.5163 64.15 Y -12.000 θ 18.37 ° 5 47.941 Y -32.393 θ -43.79 ° 6 (Image display element) Y -35.719 θ 16.65 ° Z 60.318 (1) R _y3 / R _y2 = 1.522 (2) R _y2 / R _x2 = 1.238 (3) α = 59 °.

Example 2 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 32.522 2 76.063 1.4990 69.10 Y -0.946 θ 2.91 ° 3 _Ry -156.527 1.4990 69.10 _Rx -98.656 _{Y 2.234 θ 36.99 ° K y -7.073431} Z 17.139 K x -4.186291 AR 6.03173 × 10 -11 BR -3.111158 × 10 -21 AP -40.1178 BP 1.57973 × 10 3 4 R y -392.753 1.4990 69.10 R x -124.880 Y -9.745 _{θ 29.83 ° K y 26.603285 Z 0.739} K x -2.904214 AR -6.08108 × 10 -8 BR 8.10913 × 10 -11 AP 0.0130633 BP 0.280287 5 R y 133.797 Y -40.684 θ -19.13 ° R x 898.615 Z 19.597 K y -41.405219 K _x -22.762024 AR -8.61315 × 10 ^-6 BR -1.1141 × 10 ^-9 AP -0.610618 BP 1.40395 6 (image display element) Y -32.358 θ 2.87 ° Z 62.534 (1) R _y3 / R _y2 = 2.509 (2) R _{y2 / R x2 = 1.587 (3} ) α = 53.01 °.

Example 3 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 １ (pupil) 32.000 2 ∞ 18.000 1.5163 64.15 3 _Ry -115.406 -16.000 1.5163 64.15 R _x -88.703 θ 30.00 ° K _y -2.807444 K _x -0.873733 AR -3.66094 × 10 ^-8 BR 2.09121 × 10 ^-14 AP 1.20229 AR 24.6366 4 -430.703 13.000 1.5163 64.15 Y -11.315 θ 18.37 ° 5 30.780 Y -27.507 θ -39.28 ° 6 (Image display (Element) Y-31.522 θ 7.17 ° Z 61.469 (1) R _y3 / R _y2 = 3.732 (2) R _y2 / R _x2 = 1.301 (3) α = 60 °

Example 4 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 32.000 2 -2227.303 18.000 1.4870 70.40 3 _Ry -86.054 -16.000 1.4870 70.40 R _x -71.847 Y 3.478 θ 29.21 ° K _y -0.893441 K _x -0.204808 AR -3.32767 × 10 ^-8 BR -3.29557 × 10 ^-11 AP 0.262425 AR 0.671931 4 R _y -70.490 6.966 1.4870 70.40 R _x -52.620 Y -13.000 θ 18.37 ° K _y 0 K _x 0 AR -7.62513 × 10 ^-8 BR -2.27777 × 10 ^-10 AP -1.60098 AR -1.58374 5 85.106 Y -32.132 θ -34.75 ° 6 (Image display element) Y -30.195 θ -19.83 ° Z 53.755 (1) _{R y3 / R y2 = 0.819 (} 2) R y2 / R x2 = 1.198 (3) α = 60.79 °.

Example 5 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 32.000 2 -134.369 1.161 1.70354 30.03 θ -14.22 ° 3 111.981 19.000 1.70246 48.40 4 _Ry -97.955- _{17.000 1.70246 48.40 R x -77.443 Y 3.478} θ 35.00 ° K y -2.387132 K x -1.550973 AR -6.04843 × 10 -7 BR -5.9898 × 10 -11 AP -0.113321 BP -0.375991 5 R y -109.614 1.70246 48.40 R x - _{72.524 Y -13.000 θ 25.00 ° K y} 0 K x 0 AR -1.25361 × 10 -6 BR -2.36014 × 10 -10 AP -0.41305 BP -0.506152 6 -360.157 Y -41.654 θ -46.70 ° 7 ( image display device) Y -34.523 θ -27.39 ° Z 57.718 (1 ) R y3 / R y2 = 1.119 (2) R y2 / R x2 = 1.265 (3) α = 69.22 °.

Example 6 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 39.024 2 -480.180 1.627 1.7550 27.60 Y 5.087 θ -5.57 ° 3 94.723 1.990 4 77.191 1.6554 54.18 Y- _{2.109 θ 1.81 ° 5 R y -118.749} 1.6554 54.18 R x -86.271 Y 10.000 θ 39.42 ° K y -8.00636 Z 111.291 K x -3.682175 AR -5.67283 × 10 -7 BR 4.77872 × 10 -11 AP -0.0390653 BP -0.229718 6 _{R y -149.417 1.6554 54.18 R x -81.023} Y -16.389 θ 20.00 ° K y 0 Z 2.860 K x 0 AR -1.11451 × 10 -7 BR -4.01175 × 10 -10 AP -0.409334 BP -0.0471411 7 416.536 Y -44.775 θ -54.20 ° Z 7.818 8 (image display device) Y -39.406 θ -26.59 ° Z 71.676 (1) R y3 / R y2 = 1.258 (2) R y2 / R x2 = 1.376 (3) α = 54.34 °.

Example 7 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 32.888 2 -127.238 1.546 1.7538 27.65 Y 3.651 θ -15.13 ° 3 107.965 2.643 1.6983 48.83 4 274.646 5 229.721 1.7440 44.70 Y -13.881 θ -8.230 ° Z 37.813 6 R y -109.079 1.7440 44.70 R x -74.156 Y 5.398 θ 29.535 ° K y -2.240293 Z 55.846 K x -2.129352 AR -5.37721 × 10 -7 BR -2.03548 × 10 - _{^{13 AP -0.213473 BP -2.82206 7 R y}} -145.328 1.7440 44.70 R x -62.397 Y -4.849 θ 21.46 ° K y 0 Z 37.250 K x 0 AR -8.36498 × 10 -7 BR -4.75521 × 10 -10 AP -0.458634 BP -0.508777 8 -580.390 Y -40.489 θ -56.71 ° Z 43.912 9 (image display element) Y -36.433 θ -20.70 ° Z 71.503 (1) R _y3 / R _y2 = 1.332 (2) R _y2 / R _x2 = 1.471 ( 3) α = 60.46 °.

Example 8 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 32.000 2 -208.872 1.7441 28.06 3 -187.213 1.7440 44.70 Z 10.000 θ 37.24 ° 4 _Ry -88.905 1.7440 _{44.70 R x -65.176 Z 16.453 θ 32.00} ° K y -0.308154 K x 0.092333 AR -1.50518 × 10 -7 BR 1.88192 × 10 -11 AP -0.193524 BP -1.65049 5 -187.213 1.7441 28.06 Z 10.000 θ 37.24 ° 6 R y - _{95.287 1.5027 68.73 R x -51.176 Y -13.000} θ 20.00 ° K y 0 Z 4.170 K x 0 AR -1.20201 × 10 -6 BR -3.79522 × 10 -15 AP -0.409678 BP -43.1252 7 563.531 Y -32.291 θ -49.65 ° Z 9.76 8 (image display device) Y -31.909 θ -27.97 ° Z 62.573 (1) R y3 / R y2 = 1.072 (2) R y2 / R x2 = 1.364 (3) α = 58 °.

[0114] Example 9 Face Number of curvature radius interval refractive index Abbe number (eccentricity) (inclination angle) 1 ∞ (pupil) 32.000 2 R -187.585 1.6322 48.51 K -50.20556 Y -16.345 θ -3.40 ° A 4.59937 × 10 - ^{7 B 2.58439 × 10 -10 3 49.338} 1.6418 41.23 Y -6.593 θ 30.19 ° Z 11.624 4 166.366 1.5572 64.10 Y -12.392 θ 35.42 ° Z 21.710 5 R y -95.046 1.5572 64.10 R x -66.340 Y 10.000 θ 40.00 ° K y - 0.718117 Z 11.000 K _x -0.300704 AR -5.22263 × 10 ^-8 BR -7.85534 × 10 ^-12 AP 1.16601 BP -1.4734 6 166.366 1.5572 64.10 Y -12.392 θ 35.42 ° Z 21.710 7 49.338 1.6418 41.23 Y -6.593 θ 30.19 ° Z 11.624 _{8 R y -137.574 1.6322 48.51 R x} -47.520 Y -0.499 θ 18.89 ° K y 0 Z 0.086 K x 0 AR 1.21024 × 10 -9 BR 3.74455 × 10 -14 AP -10.0983 BP -17.3357 9 176.596 Y -40.419 θ - 55.47 ° Z 8.855 10 (image display element) Y -42.854 θ -43.38 ° Z 53.820 (1) R _y3 / R _y2 = 1.447 (2) R _{y 2 / R x2 = 1.433 (3} ) α = 50 °.

Example 10 Surface No. Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 32.000 2 R -175.289 1.5941 44.13 K -155.219792 Y -14.072 θ 10.00 ° A 8.04348 × 10 ^{-7 B 9.27703 × 10 -10 3 -426.084 Y} -9.117 θ 25.38 ° Z 9.581 4 -75.870 1.6287 58.59 Y 3.984 θ 35.90 ° Z 11.611 5 R y -80.178 1.6287 58.59 R x -63.594 Y 10.000 θ 40.00 ° K y -0.869793 Z 11.000 K _x -0.688484 AR -7.17251 × 10 ^-8 BR -6.38727 × 10 ^-14 AP -0.260622 BP 3.85581 6 -75.870 Y 3.984 θ 35.90 ° Z 11.611 7 -426.084 1.5941 44.13 Y -9.117 θ 25.38 ° Z 9.581 8 _{Ry -211.470 1.5941 44.13 R x -55.393 Y -1.313} θ 9.477 ° K y 0 Z 0.568 K x 0 AR 1.18093 × 10 -9 BR 2.01542 × 10 -15 AP -9.04087 BP -14.0853 9 -32.943 Y -43.758 θ -59.05 ° Z 8.855 10 (image display element) Y -44.400 θ -29.63 ° Z 50.724 (1) R _y3 / R _y2 = 2.638 (2) R _y2 / R _x2 = 1.26 1 (3) α = 50 °.

Example 11 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 30.322 2 103.550 1.6013 61.30 ° Y-9.898 θ -19.05 ° 3 _Ry -202.010 1.6013 61.30 _{Rx -144.280 Y 14.676 θ 40.61 ° K y} -5.9195 Z 21.879 K x -14.752645 AR -1.99548 × 10 -7 BR -9.54327 × 10 -22 AP -0.427534 BP 2.19465 × 10 -3 4 225.710 1.7550 27.60 Y -9.000 θ 33.00 ° Z 10.891 5 -379.519 1.7550 27.60 Y 4.142 θ 40.31 ° Z -4.425 6 225.710 1.6013 61.30 Y -9.000 θ 33.00 ° Z 10.891 7 139.834 Y -20.502 θ -18.00 ° Z 26.7458 (image display element) Y -34.594 θ 6.59 ° _{Z 65.977 (1) R y3 /} R y2 = 1.879 (2) R y2 / R x2 = 1.400 (3) α = 68.44 °.

[0117] Example 12 Face Number of curvature radius interval refractive index Abbe number (eccentricity) (inclination angle) 1 ∞ (pupil) 28.695 2 84.793 1.7440 44.70 Y -8.729 θ -13.34 ° 3 R y -862.801 1.7440 44.70 R x - _{257.918 Y 1.554 θ 51.16 ° K y} -316.231372 Z 39.013 K x -58.426803 AR -8.67744 × 10 -9 BR 5.1966 × 10 -22 AP -1.50396 BP 2.17709 × 10 3 4 147.700 1.7374 28.35 Y -20.728 θ 45.58 ° Z 31.663 5 663.675 1.7374 28.35 Y 9.039 θ 44.57 ° Z -3.498 6 147.700 1.7440 44.70 Y -20.728 θ 45.58 ° Z 31.63 7 126.331 Y -61.667 θ -1.28 ° Z 50.9688 (Image display element) Y -47.586 θ 15.22 ° Z 93.357 (1) _{) R y3 / R y2 = -0.769} (2) R y2 / R x2 = 3.345 (3) α = 52.18 °.

Example 13 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 32.000 2 -203.051 18.000 1.6620 53.23 θ -12.00 ° 3 _Ry -93.830 -19.000 1.6620 53.23 _{Rx -77.751 Y 3.478 θ 33.00 ° K y} 1.005172 K x -0.782108 AR -8.24396 × 10 -9 BR 1.36575 × 10 -11 AP 0.197482 BP -0.0934513 4 R y -85.607 7.000 1.6620 53.23 R x -56.920 Y -13.000 θ 20.00 ° K _y 0 K _x 0 AR 3.15046 × 10 ^-7 BR -3.70111 × 10 ^-11 AP -2.22485 BP 2.37352 5 -33.119 1.682 1.7550 27.60 Y -34.962 θ -50.28 ° 6 927.298 7 (Image display element) Y -37.016 θ- 41.30 ° Z 46.780 (1) R _y3 / R _y2 = 0.912 (2) R _y2 / R _x2 = 1.207 (3) α = 69.00 °.

[0119] Example 14 Face Number of curvature radius interval refractive index Abbe number (eccentricity) (inclination angle) 1 ∞ (pupil) 25.000 2 204.694 1.6200 60.30 Y -3.185 θ -15.00 ° 3 R y -159.563 1.6200 60.30 R x - _{100.471 Y 2.186 θ 26.98 ° K y} -2.036793 Z 14.331 K x -2.676128 AR -7.18684 × 10 -10 BR -1.40819 × 10 -11 AP 11.2006 BP 1.7909 4 R y -630.426 1.6200 60.30 R x -146.568 Y -15.636 θ 12.78 _{° K y 0 Z 0.190 K x} 0 AR 1.87526 × 10 -9 BR -2.76668 × 10 -12 AP 0.0211611 BP 4.44627 5 -90.000 Y -38.038 θ -43.90 ° Z 5.289 6 -89.721 1.699 1.7550 27.60 Y -38.575 θ -43.01 ° Z 8.832 7 83.786 8 (image display device) Y -37.157 θ -12.20 ° Z 52.595 (1) R y3 / R y2 = 3.951 (2) R y2 / R x2 = 1.588 (3) α = 63.02 °.

Example 15 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 33.963 2 -161.077 6.808 1.7440 44.70 Y 1.398 θ -14.96 ° 3 -19.730 9.000 1.7356 38.60 4 _{Ry -132.032 -9.000 1.7356 38.60 R x -79.749 Y} 9.652 θ 46.62 ° K y -3.401113 K x -0.597576 AR -4.35342 × 10 -7 BR 1.37675 × 10 -14 AP 1.54099 × 10 -3 BP 9.89904 5 R y -323.588 1.7356 _{38.60 R x -87.689 Y -11.780 θ 34.70} ° K y 0 K x 0 AR -1.19882 × 10 -6 BR -6.52387 × 10 -10 AP -0.358157 BP -0.394845 6 -35.593 1.569 1.6206 36.28 Y -33.870 θ -34.42 ° Z 20.000 7 146.141 8 (image display element) Y -38.172 θ -6.45 ° Z 72.932 (1) R _y3 / R _y2 = 2.451 (2) R _y2 / R _x2 = 1.656 (3) α = 58.34 °.

Example 16 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 26.388 2 60.936 5.977 1.6392 56.73 Y -0.369 θ -14.18 ° 3 -45.628 4 -31.506 Y 0.947 θ _{-5.375 ° Z 36.416 5 R y -183.538} 1.7550 27.60 R x -112.045 Y -4.332 θ 30.69 ° K y -13.897525 Z 51.975 K x -3.33359 AR -4.04909 × 10 -7 BR 2.09722 × 10 -5 AP -0.00191601 BP 2.09722 _{^{× 10 3 6 R y 16770.468 1.7550}} 27.60 R x 13944.321 Y -6.807 θ 27.70 ° K y 0 Z 31.435 K x 0 AR -5.74255 × 10 -8 BR -1.14233 × 10 -11 AP -0.17785 BP -0.272399 7 222.419 Y - 41.467 θ -21.00 ° Z 49.118 8 (image display element) Y -28.352 θ 15.16 ° Z 67.095 (1) R _y3 / R _y2 = -91.373 (2) R _y2 / R _x2 = 1.638 (3) α = 59.31 °.

Example 17 Surface Number Curvature Radius Interval Refractive Index Abbe Number (Eccentricity) (Tilt Angle) 1 ∞ (pupil) 29.316 2 181.001 1.5626 63.71 3 -284.969 1.5626 63.71 Y 17.325 θ 27.00 ° Z 27.476 4 58.299 1.6319 38.59 Y -21.861 θ 71.46 ° Z 22.195 5 _Ry 233.704 1.6319 38.59 R _x 166.891 Y -22.800 θ 68.10 ° Z 16.701 6 58.299 1.6319 38.59 Y -21.861 θ 71.46 ° Z 22.195 7 -448.802 Y 14.600 θ 94.59 ° Z 29.5848 (Image display Element) Y 20.097 θ 88.89 ° Z 45.137 (1) R _y3 / R _y2 = −0.82 (2) R _y2 / R _x2 = 1 (3) α = 63.00 °.

Next, the first embodiment, the fifth embodiment, and the first embodiment are described.
4 are respectively shown in FIGS. 18 to 20 and FIGS.
3, shown in FIGS. In these lateral aberration diagrams, the numbers in parentheses are (horizontal angle of view, vertical angle of view)
And lateral aberration at the angle of view.

Although the image display device of the present invention has been described based on several embodiments, the present invention is not limited to these embodiments, and various modifications are possible. To configure the image display device of the present invention as a head-mounted image display device (HMD) 15, FIG. 27A is a cross-sectional view, and FIG.
As shown in a perspective view, a headband 17 is attached to the head of an observer and used. In the case of this use example, the second surface 4 of the eyepiece optical system is a semi-transmissive mirror (half mirror), and a liquid crystal shutter 16 is provided in front of the half mirror to selectively display an external image or an image display element 7.
To be superimposed on the video.

Further, when the eyepiece optical system of the image display apparatus of the present invention is used as an image forming optical system, for example, as shown in a perspective view in FIG. 28, the photographing optical system Ob and the finder optical system Fi are separately provided. It can be used for the finder optical system Fi of the compact camera Ca attached. FIG. 29 is a configuration diagram of an optical system when used as such an imaging optical system.
Shown in An objective optical system Lt can be configured by the front lens group GF, the aperture stop D, and the eyepiece optical system DS according to the present invention disposed behind the aperture stop D. The image formed by the objective optical system Lt is erected by a four-time reflecting holographic prism P provided on the observer side of the objective optical system Lt, and can be observed by the eyepiece Oc.

The image display device according to the present invention described above can be configured, for example, as follows. [1] In an image display device including an image display element for displaying an image and an eyepiece optical system for projecting an image formed by the image display element and guiding the image to an observer's eyeball, the eyepiece optical system has at least four surfaces. And those faces,
A first surface which is a refraction surface and a reflection having a positive power which is eccentric with respect to the observer's visual axis in opposition to the first surface in the order in which light rays pass according to the reverse ray tracing from the observer's eyeball to the image display element. A second surface which is a surface, a third surface which is a reflection surface facing the second surface and decentered with respect to the observer's visual axis after reflection by the second surface, and a refraction closest to the image display element. When the fourth surface is a surface, at least two of the at least four surfaces are surfaces having a finite radius of curvature, and the space formed by the first to fourth surfaces is a refractive index. Is filled with a medium larger than 1, and a principal ray from the observer's eyeball to the image display element is
In order to avoid crossing inside the eyepiece optical system,
An image display device, comprising: two reflective surfaces, wherein a primary image of an image of the image display element is formed on a retina of the observer's eyeball. [2] The image display device according to [1], wherein the third surface is a reflection surface having a convex surface facing the second surface. [3] The image display device according to [2], wherein any one of the first to fourth surfaces is an eccentric aspheric surface. [4] When a vertical plane including the observer's visual axis is defined as a YZ plane, a radius of curvature of the second plane in the YZ plane is R _y2 , and a radius of curvature in the YZ plane of the third plane is _Ry2 . _Where R _y3 is the curvature radius of the image display device, 0 <R _y3 / R _y2 <4 (1). [5] The image display device according to [3] or [4], wherein any one of the first to fourth surfaces is an anamorphic surface. [6] The vertical plane including the observer's visual axis is YZ
In the case where the plane and the horizontal plane including the observer's visual axis are defined as the XZ plane, the radius of curvature of the second plane in the YZ plane is R _y2 , and the second plane is the XZ plane. Radius of curvature at R
The image display device according to the above [3] or [5], wherein when _x2 , _Ry2 / _Rx2 > 1 (2). [7] Any one of the first and fourth surfaces of the eyepiece optical system
The image display device according to the above [6], wherein the surface is tilted or decentered with respect to the visual axis. [8] When the angle formed between the second surface of the eyepiece optical system and the visual axis is α, 30 ° <α <80 ° (3) Display device.

[9] The image display device according to the above [8], wherein a display surface of the image display element is arranged to be inclined with respect to the observer's visual axis. [10] In an image display device including an image display element that displays an image, and an eyepiece optical system that projects an image formed by the image display element and guides the image to an observer's eyeball, the eyepiece optical system includes at least four First surfaces that are refraction surfaces in the order in which light rays pass through the surfaces according to the reverse ray tracing from the observer's eyeball to the image display element.
A second surface which is a reflection surface facing the first surface and having a positive power and eccentric with respect to the observer's visual axis; an observer's visual axis opposed to the second surface and reflected by the second surface; If the third surface is a reflecting surface decentered with respect to the first surface and the fourth surface is a refracting surface closest to the image display device, at least two of the at least four surfaces have a finite curvature. A decentered optical element, which is a surface having a radius, wherein a space formed by the first surface to the fourth surface is filled with a medium having a refractive index greater than 1, and at least one optical surface having a refraction function; Is arranged in an optical path from the image display element to the observer's eyeball. [11] The at least one optical surface is the first optical surface.
[10] characterized in that the surface is configured to generate a reverse chromatic aberration amount substantially equal to the chromatic aberration amount generated in the surface.
The image display device as described in the above. [12] The at least one optical surface is the first optical surface.
The image display device according to [10], wherein the power of the surface, the refractive index of the medium before and after the surface, and the Abbe number are set so as to generate a chromatic aberration amount substantially equal to the chromatic aberration amount generated on the surface. [13] The image display device according to [11], wherein the at least one optical surface is disposed between the observer's eyeball and the first surface of the eccentric optical element. [14] The image display device according to [11], wherein the at least one optical surface is disposed between a second surface and a third surface of the decentered optical element. [15] The image display device according to [11], wherein the at least one optical surface is disposed between a fourth surface of the decentered optical element and the image display element. [16] The above [1], wherein the at least one optical surface is decentered with respect to the observer's visual axis.
1] The image display device according to the above. [17] The image display device according to any one of [10 to [16], wherein the at least one optical surface is a bonding surface. [18] The image display device according to [17], wherein the at least one optical surface and the decentered optical element form an air lens. [19] The image display device according to any one of [1] to [18], further including positioning means for positioning the image display element and the eyepiece optical system with respect to the observer's head. [20] The image display device according to [1], further comprising: a support unit configured to support the image display element and the eyepiece optical system with respect to the observer's head. ] The image display device according to any one of [18] to [18]. [21] The image display device according to any one of [1] to [20], further including a support unit configured to support at least two sets of the image display device at a fixed interval. [22] The image display device according to any one of [1] to [18], wherein the eyepiece optical system in the image display device is used as an imaging optical system.

[0127]

As is apparent from the above description, according to the image forming optical system of the present invention, a novel image forming optical system such as a viewfinder optical system of a very small and lightweight camera having a wide angle of view is provided. be able to.

[Brief description of the drawings]

FIG. 1 is an optical path diagram of Embodiment 1 of an image display device according to the present invention.

FIG. 2 is an optical path diagram of a second embodiment of the image display device according to the present invention.

FIG. 3 is an optical path diagram of a third embodiment of the image display device according to the present invention.

FIG. 4 is an optical path diagram of an image display device according to a fourth embodiment of the present invention.

FIG. 5 is an optical path diagram of Embodiment 5 of the image display device according to the present invention.

FIG. 6 is an optical path diagram of Embodiment 6 of the image display device according to the present invention.

FIG. 7 is an optical path diagram of Embodiment 7 of the image display device according to the present invention.

FIG. 8 is an optical path diagram of Embodiment 8 of the image display device according to the present invention.

FIG. 9 is an optical path diagram of Embodiment 9 of the image display device based on the present invention.

FIG. 10 shows an image display apparatus according to a tenth embodiment of the present invention.
FIG.

FIG. 11 is an eleventh embodiment of the image display apparatus according to the present invention.
FIG.

FIG. 12 is a twelfth embodiment of the image display apparatus according to the present invention.
FIG.

FIG. 13 shows an image display apparatus according to a thirteenth embodiment of the present invention.
FIG.

FIG. 14 shows an image display apparatus according to a fourteenth embodiment of the present invention.
FIG.

FIG. 15 shows an image display apparatus according to a fifteenth embodiment of the present invention.
FIG.

FIG. 16 shows an image display device according to a sixteenth embodiment of the present invention.
FIG.

FIG. 17 shows an image display apparatus according to a seventeenth embodiment of the present invention.
FIG.

FIG. 18 is a part of a lateral aberration diagram of the first embodiment based on the present invention.

FIG. 19 is the remaining part of the lateral aberration diagram of the first embodiment based on the present invention.

FIG. 20 is the remaining part of the lateral aberration diagram of Example 1 based on the present invention.

FIG. 21 is a part of a lateral aberration diagram of Example 5 based on the present invention.

FIG. 22 is the remaining part of the lateral aberration diagram of Example 5 based on the present invention.

FIG. 23 is the remaining portion of the lateral aberration diagram of Example 5 based on the present invention.

FIG. 24 is a part of a lateral aberration diagram of Example 14 based on the present invention.

FIG. 25 is a remaining part of the lateral aberration diagram of Example 14 based on the present invention.

FIG. 26 is the remaining part of the lateral aberration diagram of Example 14 based on the present invention.

FIG. 27 is a sectional view and a perspective view of a head mounted image display device according to the present invention.

FIG. 28 is a configuration diagram when an eyepiece optical system according to the present invention is used as an imaging optical system.

FIG. 29 is a configuration diagram of an optical system when an eyepiece optical system according to the present invention is used as an imaging optical system.

FIG. 30 is a diagram showing an optical system of one conventional image display device.

FIG. 31 is a diagram showing an optical system of another conventional image display device.

FIG. 32 is a diagram showing an optical system of still another conventional image display device.

FIG. 33 is a diagram showing an optical system of another conventional image display device.

FIG. 34 is a diagram illustrating an optical system of still another conventional image display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Observer pupil position 2 ... Observer's visual axis 3 ... 1st surface of eyepiece optical system 4 ... 2nd surface of eyepiece optical system 5 ... 3rd surface of eyepiece optical system 6 ... 4th surface of eyepiece optical system 7 ... Image display element 9 ... Eccentric optical element 10 ... Optical surface 11 ... Negative lens 12 ... Positive lens 13 ... Joint lens 14 ... Backside mirror 15 ... Head mounted image display (HMD) 16 ... Liquid crystal shutter 17 ... Headband Ob ... Photographing optical system Fi: finder optical system Ca: compact camera GF: front lens group D: aperture stop DS: eyepiece optical system (the present invention) Lt: objective optical system P: holo prism Oc: eyepiece lens

Claims (18)

[Claims] 1. An imaging optical system having a stop and forming an object image, wherein the imaging optical system has at least four surfaces, and traces those surfaces from the stop to the object image. The first surface, which is a refraction surface, and the first surface
A second surface, which is a reflecting surface having a positive power and eccentric to the optical axis and facing the surface, and a reflecting surface eccentric to the optical axis after being reflected by the second surface and facing the second surface. In the case where the third surface is a fourth surface which is a refraction surface closest to the object image, at least two of the at least four surfaces are surfaces having a finite radius of curvature, and the third surface is a surface having a finite radius of curvature. A space formed by the first to fourth surfaces includes an eccentric optical element in which a medium having a refractive index greater than 1 is filled, and a principal ray from the stop to the object image is formed inside the eccentric optical element. Wherein the two reflecting surfaces are disposed so as not to intersect with each other, and the object image is formed as a primary image without having an image surface inside the decentered optical element. Imaging optics. 2. The imaging optical system according to claim 1, wherein the third surface is a reflection surface having a convex surface facing the second surface. 3. The imaging optical system according to claim 2, wherein any one of the first to fourth surfaces is a non-rotationally symmetric aspherical surface. 4. When the vertical plane including the optical axis is defined as a YZ plane, the radius of curvature of the second plane in the YZ plane is R _y2 , and the third plane is the YZ plane. 4. The imaging optical system according to claim 3, wherein, when a radius of curvature in _Ry3 is _Ry3 , 0 < _Ry3 / _Ry2 <4 (1). 5. The apparatus according to claim 3, wherein any one of the first to fourth surfaces is an anamorphic surface.
Or the imaging optical system according to 4. 6. A vertical plane including the optical axis is YZ.
In the case where a plane and a horizontal plane including the optical axis are defined as an XZ plane, a radius of curvature of the second plane in the YZ plane is R _y2 , and a curvature of the second plane in the XZ plane is Radius R _x2
The image forming optical system according to claim 3, wherein R _y2 / R _x2 > 1 (2). 7. The imaging optical system according to claim 6, wherein one of the first surface and the fourth surface of the imaging optical system is tilted or decentered with respect to an optical axis. system. 8. The image forming apparatus according to claim 7, wherein when an angle between the second surface of the imaging optical system and the visual axis is α, 30 ° <α <80 ° (3). Imaging optics. 9. The imaging optical system according to claim 8, wherein an image plane of the object image is arranged to be inclined with respect to the optical axis. 10. An imaging optical system having a stop and forming an object image, wherein the imaging optical system has at least four surfaces, and traces those surfaces from the stop to the object image. The first surface, which is a refraction surface, and the first surface
A second surface, which is a reflecting surface having a positive power and eccentric to the optical axis and facing the surface, and a reflecting surface eccentric to the optical axis after being reflected by the second surface and facing the second surface. In the case where the third surface is a fourth surface which is a refraction surface closest to the object image, at least two of the at least four surfaces are surfaces having a finite radius of curvature, and the third surface is a surface having a finite radius of curvature. A decentered optical element in which a space formed by the first to fourth surfaces is filled with a medium having a refractive index greater than 1, and at least one optical surface having a refracting action, an optical path from the stop to the object image An imaging optical system characterized by being disposed inside. 11. The apparatus according to claim 10, wherein the at least one optical surface is configured to generate a reverse chromatic aberration amount substantially equal to the chromatic aberration amount generated in the first surface. Imaging optics. 12. The power of the surface, the refractive index of the medium before and after the surface, and the Abbe's power so that the at least one optical surface generates a reverse chromatic aberration amount substantially equal to the chromatic aberration amount generated in the first surface. The imaging optical system according to claim 10, wherein the number is set. 13. The imaging optical system according to claim 10, wherein said at least one optical surface is disposed between said stop and a first surface of said decentered optical element. 14. The imaging optical system according to claim 10, wherein said at least one optical surface is arranged between a second surface and a third surface of said decentered optical element. 15. The imaging optical system according to claim 10, wherein said at least one optical surface is disposed between a fourth surface of said decentered optical element and said object image. 16. The optical system according to claim 1, wherein the at least one optical surface is decentered with respect to the optical axis.
0. The imaging optical system according to 0. 17. The imaging optical system according to claim 10, wherein said at least one optical surface is a bonding surface. 18. The imaging optical system according to claim 10, wherein said at least one optical surface and said decentered optical element form an air lens.