JP2001264683A - Information display optical system, optical element or optical system and information display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an information display optical system by which a thin and compact configuration is realized, an excellent image is obtained even by a wide display viewing angle and also an outer world is naturally observed by see-through. SOLUTION: The system is characterized in that the system has two prisms each provided with at least two reflection surfaces which are arranged to face mutually and with the other reflection surface, at least one of the reflection surfaces which are arranged to face mutually is a light fluxes selection surface for selectively performing transmission and reflection by an incident angle, respective image light from respective image display means 3 and 4, which are made incident on the prisms are reflected between the reflection surfaces which are arranged to face mutually, reflected from the other reflection surfaces, pass through the light fluxes selection surface and respectively guided to one of the pupils of an observer.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an information display optical system, and more particularly, to an information display optical system for an image display device used in front of a viewer.

[0002]

2. Description of the Related Art Conventionally, there has been known an image display device which is mounted on a head or a face or held by a hand and is used in front of an observer's eyes, for example, for use in virtual reality or personal theater. It has been commercialized. Also,
Recently, what is used as a display for a so-called wearable computer has been studied.

As a specific configuration, for example, Japanese Patent Application Laid-Open
As described in Japanese Patent Application Laid-Open No. 0-246865, a visual display device having an eyepiece optical system for enlarging and projecting an image formed by a two-dimensional display means as a virtual image by guiding the image to an observer's eyeball. Has first two-dimensional display means and second two-dimensional display means, wherein the eyepiece optical system has a first surface having a reflection function and a transmission function, and a second surface having at least a reflection function, A third surface having at least a reflecting action, wherein the first surface is arranged to face an observer's eyeball, the second surface is arranged to face the first surface, and the third surface is The display images of the first two-dimensional display means and the second two-dimensional display means are observed by being arranged so as to face the first surface and be juxtaposed with the second surface. To the eyeball of the user.

[0004]

However, in the configuration described in Japanese Patent Laid-Open No. Hei 10-246865, since the image light beam passes through the half mirror twice due to the configuration of the optical system, the amount of display light is reduced. Becomes 1/4 or less, and the image becomes dark. Further, since there is no opposing inter-surface reflecting portion, that is, a light beam guiding portion, inside the prism, the prism becomes thicker. Further, since the display element is arranged in front of the observer, a so-called see-through function for simultaneously viewing the display image and the external image cannot be provided.

In view of the above problems, the present invention enables a thin and compact configuration, obtains a good image even at a wide display angle of view, and enables natural see-through observation of the outside world. It is an object to provide an information display optical system.

[0006]

In order to achieve the above object, according to the present invention, there are provided two prisms each having at least two reflecting surfaces arranged opposite to each other and another reflecting surface, At least one of the reflecting surfaces disposed opposite to each other is a light beam selecting surface for selectively transmitting and reflecting according to an incident angle, and each of the image light from each image display means incident on each prism. Is reflected between the reflection surfaces arranged opposite to each other, subsequently reflected on the other surface, and further transmitted through the light beam selection surface, and then guided to one pupil of the observer. Features.

Further, the other reflecting surface has an optical power for enlarging and projecting the image light onto the pupil of the observer. Further, the other reflection surface is arranged to be inclined with respect to the projection direction of the image light. The display areas of the respective image lights are connected to each other.

Further, the invention is characterized in that a deflection correction member for correcting the deflection of the external light passing through the prism is provided.
Further, the other reflection surface is a hologram surface composed of a reflection hologram. Further, the hologram is of a volume type and a phase type. Also, the hologram surface is flat.

Further, the reflection surfaces arranged opposite to each other are substantially parallel to each other. Alternatively, the reflection surfaces arranged opposite to each other form an angle that is open to the incident side of the image light to the prism.

Further, the reflection between the reflection surfaces arranged opposite to each other is a total reflection. Further, at least one of the reflecting surfaces arranged opposite to each other is a curved surface.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. The information display optical system of the present invention has two image display elements, and the light flux of each display image is made to enter one pupil by using an eyepiece optical system corresponding to each image display element. Each image display element and eyepiece optical system correspond to a different display area, and by observing them together, it is possible to realize a thin and compact configuration while expanding the angle of view (display viewing angle). I'm trying.

In addition, since the inter-surface reflection of the opposing reflecting surfaces of the eyepiece optical system is total reflection, thereby guiding the luminous flux of the displayed image, the image display element may be configured not to block the normal field of view. it can. Therefore, since external light is not blocked, a so-called see-through function for simultaneously viewing the display image and the external image can be provided, and a wide external observation area can be obtained.

Further, when a hologram is used as the eyepiece function, a better and more natural see-through observation of the outside world is possible. A hologram can have optical power even in a plane, so when such a see-through function is provided, the hologram acts as a lens by diffractive reflection on the luminous flux of the display image, and acts on the external light Since it has no power, natural observation of the outside world image is possible.

FIG. 1 is a graph for explaining the diffraction wavelength width of transmission type and reflection type holograms. In the figure, when the refractive index of the hologram light-sensitive material is 1.5, the recording wavelength is 530 nm, and the thickness of the hologram light-sensitive material is 5 μm, the wavelength selectivity of the transmission hologram and the reflection hologram with respect to the angle difference between the incident light and the emitted light is shown. Is shown. In the figure, the horizontal axis represents the angle difference, and the vertical axis represents the diffraction wavelength width. As shown in the figure, when the angle difference is 90 degrees or less, that is, in the case of the transmission type hologram, the diffraction wavelength width is as large as one hundred and several tens nm or more. Here, the visible light range is about 400 nm to 700 nm and 300 n
Since the wavelength width is only about m, the transmission hologram may act on almost all visible light.

On the other hand, when the angle difference is 90 degrees or more, that is, in the case of the reflection type hologram, the diffraction wavelength width becomes much narrower than that of the transmission type hologram, and the wavelength selectivity becomes extremely high. . In other words, reflection holograms
It has the property of acting on certain wavelengths but not on other wavelengths. Therefore, when the reflection hologram is used as a combiner for a so-called see-through function for simultaneously viewing a display image and an external image, the external hologram is affected by only a part of the wavelength of the external light. It is possible to perform bright and favorable see-through observation.

FIG. 2 is a graph showing an example of the relationship between the intensity of reflected light and the intensity of transmitted light with respect to the wavelength of incident light in the visible light range in a monochromatic reflection hologram. In the figure, the horizontal axis represents wavelength (nm), and the vertical axis represents reflection or transmittance (%). A curve a represented by a solid line represents the reflectance, and a curve b represented by the dashed line represents the transmittance. Since the reflection hologram acts only on light having a specific wavelength (diffraction wavelength), it reflects light near 530 nm and transmits light in other wavelength ranges, as shown in FIG. This enables a see-through type information display in which the external light and the image light are superimposed and observed.

FIG. 3 is a graph showing an example of the relationship between the wavelength of incident light in the visible light range and the intensity of reflected light and transmitted light in a color reflection hologram. In the figure, the horizontal axis represents wavelength (nm), and the vertical axis represents reflection or transmittance (%). A curve a represented by a solid line represents the reflectance, and a curve b represented by the dashed line represents the transmittance. Since a reflection type hologram acts only on light of a specific wavelength (diffraction wavelength), as shown in the figure, the reflection hologram reflects light in the R, G, and B wavelength ranges and light in other wavelength ranges. Is transmitted.

Thus, even when the image light is displayed in color, a see-through type information display in which the external light and the image light are superimposed and observed can be realized. Since holograms have diffraction wavelengths corresponding to recording wavelengths, color holograms such as those described above require multiple exposures to different holograms on a single hologram photosensitive material, or lamination of holograms created at different recording wavelengths. It can be realized with.

FIG. 4 is a longitudinal sectional view schematically showing the configuration of the information display optical system according to the first embodiment of the present invention. The upper optical system in the figure corresponds to the upper side of the display area, and the lower optical system corresponds to the lower side of the display area. Each optical system is vertically symmetrically arranged at the center of the pupil, that is, at the center of the display area. Therefore, the following description and the construction data described later are represented by the upper optical system. This is the same in the following embodiments.

In FIG. 1, the prism 1 has a plate shape opened obliquely upward to the right, and its upper end surface is an incident surface r7. And it has the 1st reflection surface r6 and the 2nd reflection surface r5 which are respectively arrange | positioned facing right and left of the figure, and these are arrange | positioned substantially parallel. Further, a concave reflecting surface r3 is provided at the lower end of the prism 1 so as to be inclined toward the light incident surface side of the prism. Thus, the upper and lower optical systems do not overlap.
The first reflection surface r6 and the concave reflection surface r3 form a wedge shape. The first reflecting surface r6 has light beam selecting surfaces r4 and r2 for selectively performing total reflection and transmission depending on the incident angle on the same surface.

The pupil 2 is located on the left side of the drawing when viewed from the lower end of the prism 1. The pupil 2 has a pupil surface r1. In the coordinate system, the center of the pupil 2 is set as the origin, the front direction of the pupil 2, that is, the right direction in the figure is defined as the positive Z-axis direction, the upward direction is defined as the positive Y-axis direction, and the paper surface is defined as the YZ plane. In addition, the direction perpendicular to the paper surface is defined as the X-axis plus direction. This is the same in the following embodiments. Note that an image display element 3 made of, for example, transmissive liquid crystal is disposed diagonally above and right of the entrance surface r7 of the prism 1, and the front display surface is designated by r8.

As shown in FIG. 1, the light flux L of the display image from the display surface r8 of the image display element 3 enters the entrance surface r7 of the prism 1. The light beam L entering the prism 1 from the entrance surface r7 enters the first reflection surface r6, where it is reflected (total reflection). The light beam L reflected by the first reflecting surface r6 is incident on a second reflecting surface r5 disposed opposite thereto,
Here, it is reflected (total reflection). The light beam L reflected by the second reflection surface r5 is incident on the light beam selection surface r4, where it is reflected (total reflection). Light beam L reflected by light beam selection surface r4
Enters the concave reflecting surface r3.

In the present embodiment, the concave reflecting surface is disposed obliquely with respect to the light flux of the display image and has optical power as an eyepiece function, so that it becomes a non-axially symmetric optical system. In such a non-axially symmetric optical system, when only the same function as the coaxial lens is performed, asymmetric distortion (trapezoidal distortion) or field curvature due to eccentricity occurs. Therefore, in order to prevent these occurrences, it is desirable that the concave reflecting surface has not only a rotationally symmetric wavefront reproducibility but also a free-form surface wavefront reproducibility. For this reason, such a concave reflecting surface is formed of an anamorphic aspherical surface, and is optimized so as to correct aberration due to eccentricity.

In the present embodiment, the concave surface of the prism 1 is configured by reflecting the light flux L a plurality of times by the reflecting surfaces disposed opposite to each other, that is, the first reflecting surface r6 and the second reflecting surface r5. The light guide to the reflection surface r3 is formed thin. Further, the light beam L is folded in the optical path by the light beam selection surface that selectively performs total reflection and transmission according to the incident angle,
The light beam can be extracted without dividing the optical path, and a compact arrangement of each optical element is realized. In addition, the amount of eccentricity of the concave reflecting surface is also reduced, and the occurrence of eccentric aberration is small, and a good display image can be obtained.

In this embodiment, the display images of the upper and lower image display elements 3 are completely independent of each other vertically at the center of the display area. However, each image display element 3 is expanded. Alternatively, the display areas may overlap each other. By doing so, it is possible to eliminate partial omission of the pupil diameter at the center of the display area. In addition, a concave reflection surface is used as a half mirror to partially reflect a light beam, and a deflection correction member that corrects the deflection of the external light is disposed here. Type information can be displayed. This will be described below.

In this embodiment, the opposing reflecting surfaces (first and second reflecting surfaces) are arranged in parallel, and the reflecting surfaces of the upper and lower prisms 1 are respectively arranged on the same plane. I have. Further, the prism 1 for the light flux of the display image
The reflection inside is performed by total reflection, and no reflection coating or the like is applied to the reflection surface. Therefore, this portion can transmit the external light from the plus direction or the minus direction of the Z axis without distortion, and can guide the light to the pupil 2. However, in order to provide the light beam selection surface with light beam selectivity for selectively performing total reflection and transmission depending on the incident angle, the concave reflection surface r3 and the light beam selection surface are arranged not at parallel but at an angle. .

That is, in the case of the upper prism 1, for example, the concave reflecting surface r3 is inclined and arranged below the prism 1, so that the lower portion of the prism 1 becomes wedge-shaped, and the external light passing through this portion is Come out deflected.
Also, optical power acts to transmit through the concave surface, and a good see-through function cannot be ensured. Therefore, in the present embodiment, as shown in the drawing, the concave surface r3 has an inclined surface 4a which is joined or arranged in parallel with a small interval, and has a surface 4b which coincides with the extension surface of the second reflective surface. The deflection correction member 4 is mounted. Thereby, the deflection of the external light is corrected, and natural external light observation becomes possible.

FIG. 5 is a longitudinal sectional view schematically showing the configuration of the information display optical system according to the second embodiment of the present invention. In the present embodiment, as compared with the first embodiment, the image display unit is prism-arranged by arranging opposing reflection surfaces (first and second reflection surfaces) at an open angle on the light incident surface side. This is an example in which the optical system is arranged almost directly above the optical system and the overall optical system is made thin. The manner in which the light beam L passes through the prism 1 is the same as in the first embodiment.

FIG. 6 is a longitudinal sectional view schematically showing the configuration of the information display optical system according to the third embodiment of the present invention. The basic configuration is the same as in the first and second embodiments, but here, the opposing reflecting surfaces are curved to provide an aberration correction function for the displayed image, thereby improving the image quality. Specifically, this curved surface is a symmetric curved surface around the pupil center. In the case of performing a see-through observation of an external world image, the power of this curved surface causes the prism 1 to function as a lens and has a diopter correction function, so that the prism 1 can also be used as ordinary glasses. It is.

FIG. 7 is a longitudinal sectional view schematically showing the configuration of an information display optical system according to a fourth embodiment of the present invention. The basic configuration is the same as that of the first embodiment, but here, the reflection surface is changed from a concave reflection surface to a hologram surface. The hologram can have optical power even when it is flat, so if it has a see-through function, it acts as a lens by diffractive reflection on the luminous flux of the displayed image and non-power on external light. Therefore, natural observation of the external world image becomes possible. The hologram used is
In order to obtain a bright display image with high diffraction efficiency and a bright external image, a so-called volume type phase reflection hologram having small light absorption is suitable.

In the figure, the wavelength of the light beam L of the display image substantially coincides with the wavelength at which the diffraction efficiency of the hologram lens on the hologram surface r3 becomes a peak, and the light beam L is reflected by the hologram surface r3. The light beam L reflected by the hologram surface r3 is transmitted through the light beam selection surface r2 and guided to the pupil surface r1 of the pupil 2. The hologram lens on the hologram surface r3 has an optical power and has an eyepiece function for enlarging and observing a display image. As a result, the light beam L is enlarged and projected on the pupil of the observer.

Here, since only one hologram has an eyepiece function, a simple configuration is possible. Further, since the hologram surface r3 is a flat surface, it is easy to form a hologram sensitive material, and furthermore, the positional accuracy when the inclined surface 4a of the deflection correction member 4 is abutted is low, and
Mounting becomes easy.

The hologram basically has the best wavefront reproducibility and the highest diffraction efficiency when a light beam having the same wavelength and angle as the light beam that created the hologram is provided. Is preferably a light beam having an intensity peak at a wavelength at which the diffraction efficiency of the hologram lens formed on the hologram surface r3 becomes a peak.

For example, when a hologram having a diffraction efficiency peak near 530 nm is used, and a non-self-luminous element such as a liquid crystal is used as the image display element 3, the light source for illuminating this element emits light at about 530 nm. A green LED having an intensity peak is suitable. LED has a half width of 20 to 4
Since it has an emission wavelength width of 0 nm, when this is used as a light source of display image light, a configuration with high energy efficiency can be obtained.

It is needless to say that a laser having the same emission wavelength as the laser used for producing the hologram may be used as the light source. In addition, as described with reference to FIG. 3, the hologram may be a color hologram having a diffraction efficiency peak at a plurality of wavelengths. As described in the description of FIG. 2, the reflection hologram acts only on light having a specific wavelength (diffraction wavelength), so that light beams other than the diffraction wavelength are transmitted without being reflected. As a result, in the fourth embodiment using the hologram, even better see-through information display can be performed as compared with the first embodiment.
This is the same in the case of a color hologram.

FIG. 8 is a longitudinal sectional view schematically showing the configuration of an information display optical system according to a fifth embodiment of the present invention. This embodiment is different from the fourth embodiment in that the opposing reflecting surfaces (first and second reflecting surfaces) are arranged at an open angle on the light-incident surface side so that the image display unit is prism-shaped. This is an example in which the optical system is arranged almost directly above the optical system to reduce the thickness of the entire optical system. The manner in which the light beam L passes through the prism 1 is the same as in the fourth embodiment.

FIGS. 9 and 10 show the sixth and seventh embodiments of the present invention, respectively.
It is a longitudinal section showing typically composition of an information display optical system of a 7th embodiment. The basic configuration is the same as that of each of the second and fifth embodiments. However, in this embodiment, a see-through type information in which the external light and the image light are superimposed and observed by disposing a deflection correction member for correcting the deflection of the external light. Display is enabled. This will be described below.

In the second and fifth embodiments, the opposing reflecting surfaces (first and second reflecting surfaces) are arranged at an open angle on the light-incident surface side so that the image display unit is formed of a prism. The optical system is placed almost directly above to reduce the overall thickness of the optical system.
Further, in order to provide the light beam selection surface with light beam selectivity for selectively performing total reflection and transmission depending on the incident angle, the concave reflection surface or the hologram surface r3 and the light beam selection surface are arranged not at an angle but at an angle. Have been.

That is, to exemplify the case of the upper prism 1, the second reflecting surface r5 and the concave reflecting surface or the hologram surface r3 are arranged on the prism 1 with an inclination, so that the prism 1 becomes wedge-shaped. The external light passing through this portion is deflected and emerges. Further, when the light passes through the concave surface, optical power is further applied, and a good see-through function is not secured.

Therefore, in the sixth embodiment, as shown in FIG. 9, the second reflecting surface r5 and the concave reflecting surface r3 are joined.
Alternatively, a deflection correction member 7 which is a prism having inclined surfaces 7a and 7b arranged in parallel at a minute interval and having a surface 7c parallel to the first reflection surface is mounted. In the seventh embodiment, as shown in FIG. 10, the inclined surfaces 7a and 7b bonded to the second reflecting surface r5 and the hologram surface r3 or arranged in parallel with a small space therebetween, respectively.
And a deflection correction member 7 which is a prism having a surface 7c parallel to the first reflection surface. Thereby, the deflection of the external light is corrected, and natural external light observation becomes possible.

FIG. 11 is an external view of an example of a head mounted image display device to which the present invention is applied. As described above, since the information display optical system of the present invention can have a thin configuration, a spectacle-shaped image display device can be realized as shown in FIG. Here, the prism 1 and the deflection correction member 4 (or 7)
The illumination optical system 8 is arranged on the upper and lower parts.

From the end of the frame 9, the cord 1
0 is extended, and is connected to a mobile personal computer, a mobile phone, or the like (not shown), and receives image information therefrom. In addition, it can be wireless at short distances. And, due to the characteristics of the hologram described above,
Since a high see-through function is also ensured, an HMD (Head Mounted Display) that can be always worn with little burden on the user is provided. This is also optimal as a so-called wearable computer image display device.

FIG. 12 is a longitudinal sectional view of the information display optical system of the head mounted image display device. As shown in the figure, light emitted from a light source 6 including an LED or the like in an illumination optical system 8 illuminates the image display element 3 via a condenser lens 5. Then, the light is modulated and emitted as image light, passes through the prism 1, is reflected by the concave reflection surface or the hologram surface r3, and reaches the pupil 2. At this time, see-through observation of an external image is also possible through the prism 1 and the deflection correction member 4. Further, by providing the prism 1 and the deflection correction member 4 with a function as a lens and having a diopter correction function, the prism 1 and the deflection correction member 4 can also be used as ordinary glasses.

Hereinafter, the configuration of the optical system according to the present invention will be described more specifically with reference to construction data. Examples 1 to 6 described below correspond to the first to sixth examples described above.
, Respectively. All holograms used in the examples of the present invention have a creation wavelength (recording wavelength) and a used wavelength of 532 nm, and the use order is the first order.
In addition, the arrangement data of each plane is expressed as a global coordinate system having the origin at the center of the pupil plane. The directions of the X, Y, and Z axes are as described with reference to FIG. The positions of the respective surfaces are indicated as XSC, YSC, and ZSC, respectively. The unit is mm. When the X, Y, and Z axes are rotation axes, the inclination of each surface is represented as ASC, BSC, or CSC. The unit is degree.

Regarding the definition of the hologram surface, the hologram is uniquely defined by defining two light beams used for the creation. The definition of the two light beams is based on the light source position of each light beam and whether the emitted beam from each light source is a convergent beam (VIA) or a divergent beam (REA). The coordinates of the first point light source (HV1) and the second point light source (HV2) are (HX1, HY1, HZ1), (HX2, HY2, HZ), respectively.
2).

In each embodiment, since the wavefront is reproduced by a complex hologram, the direction function of the exit light beam with respect to the incident light beam is defined by the phase function φ in addition to the definition of the two light beams. The phase function φ is a generator polynomial based on the position (X, Y) of the hologram surface shown in Expression 1 below, and is represented by a monomial in ascending order from first to tenth order. In the construction data, the coefficient C of the phase function φ
Indicates _j .

[0047]

(Equation 1)

[0048] The numbers j of the coefficient C _j is, m, and n X,
It is represented by the following equation 2 as an index of Y.

[0049]

(Equation 2)

Here, the cosine in the X-axis, Y-axis, and Z-axis directions of the emitted light beam is expressed by the following equation (3).

[0051]

(Equation 3)

In equation (3), l ', m', and n 'are the normal vectors of the emitted light beam, l, m, and n are the normal vectors of the incident light beam, λ is the wavelength of the reproduced light beam, and λ ₀ is This is the wavelength of the hologram creation light beam.

In the construction data, the parameters relating to the anamorphic aspherical surface are defined by the following equation (4) when the origin is the intersection of each surface and its optical axis and the optical axis is the Z axis. (Unit: mm). The radius of curvature in the data is the radius of curvature in the Y-axis direction, and RDX is the radius of curvature in the X-axis direction.

[0054]

(Equation 4)

Here, CUX and CUY are curvatures in the X-axis direction and the Y-axis direction, respectively.

<< Example 1 >> Surface number Curvature radius Medium r1 (pupil surface) INFINITY AIR r2 (light flux selection surface) INFINITY PMMA r3 (reflection surface) -67.91807 PMMA anamorphic aspheric surface KY: -14.724953 KX: -20.432877 RDX : -47.45973 AR:-. 732699 × 10 ^-5 BR:-. 163991 × 10 ^-7 CR: 0.907725 × 10 ^-10 AP:-. 281933 × 10 ⁺⁰ BP:-. 580876 × 10 ⁺⁰ CP:-. 477085 × 10 ⁺⁰ r4 (beam selection surface) INFINITY PMMA r5 (second reflection surface) INFINITY PMMA r6 (first reflection surface) INFINITY PMMA r7 (incident surface) 18.86098 PMMA Anamorphic aspheric surface KY: 4.210342 KX: -1.870210 RDX: 20.49422 AR: 0.791098 × 10 ^-5 BR: 0.825128 × 10 ^-7 CR: 0.415047 × 10 ^-7 AP: 0.774495 × 10 ⁺⁰ BP: -.447736 × 10 ⁺⁰ CP: 0.512750 × 10 ^-1 r8 (Display surface) INFINITY

Position of each surface Surface XSC YSC ZSC ASC BSC CSC r1 0 0 0 0 0 0 r2 0 -1.5 14 0 0 0 r3 0 2.773 12.370 33.850 0 0 r4 0 -1.5 14 0 0 0 r5 0 -1.5 17.5 0 0 0 r6 0 -1.5 14 0 0 0 r7 0 -22.677 17.183 -85.277 0 0 r8 0 -24.465 20.645 -29.042 0 0

Example 2 Surface Number Curvature Radius Medium r1 (pupil surface) INFINITY AIR r2 (light flux selection surface) INFINITY PMMA r3 (reflection surface) -65.81128 PMMA Anamorphic aspheric surface KY: -18.964415 KX: -26.532434 RDX : -45.77309 AR:-. 416493 × 10 ^-5 BR:-. 227125 × 10 ^-7 CR: 0.714349 × 10 ^-10 AP:-. 111311 × 10 ⁺⁰ BP:-. 508864 × 10 ⁺⁰ CP:-. 483015 × 10 ⁺⁰ r4 (light flux selection surface) INFINITY PMMA r5 (second reflection surface) INFINITY PMMA r6 (first reflection surface) INFINITY PMMA r7 (incident surface) 682.37441 PMMA Anamorphic aspheric surface KY: -0.051939 KX : 356.459186 RDX: -107.42767 AR: 0.251651 × 10 ^-4 BR:-. 239984 × 10 ^-6 CR: 0.107859 × 10 ^-7 AP: 0.144849 × 10 ⁺¹ BP: 0.119571 × 10 ⁺⁰ CP: 0.110662 × 10 ⁺⁰ r8 (display surface) INFINITY

Arrangement of each surface Surface XSC YSC ZSC ASC BSC CSC r1 0 0 0 0 0 0 r2 0 -1.5 14 0 0 0 r3 0 6.695 9.614 37.425 0 0 r4 0 -1.5 14 0 0 0 r5 0 -6.2 17.5 3 0 0 r6 0 -1.5 14 0 0 0 r7 0 -26.746 22.320 -96.260 0 0 r8 0 -28.092 19.877 -38.862 0 0

Example 3 Surface Number Curvature Radius Medium r1 (pupil surface) INFINITY AIR r2 (light beam selection surface) -400 PMMA r3 (reflection surface) -53.50019 PMMA Anamorphic aspheric surface KY: -11.608841 KX: -18.114889 RDX: -44.01804 AR:-. 941850 × 10 ^-5 BR:-. 197815 × 10 ^-7 CR: 0.150623 × 10 ^-9 AP:-. 151288 × 10 ⁺⁰ BP:-. 106976 × 10 ⁺¹ CP:- .924051 × 10 ⁺⁰ r4 (light flux selection surface) -400 PMMA r5 (second reflection surface) -477.32126 PMMA rotationally symmetric aspheric surface K: 0.000000 A: 0.793161 × 10 ^-7 B: 0.28269 × 10 ^-8 C: 0.227445 × 10 ^-11 r6 (first reflective surface) -400 PMMA r7 (incident surface) 8.78367 PMMA Anamorphic aspheric surface KY: -5.765127 KX: 0.620164 RDX: 20.95733 AR: 0.133517 × 10 ^-4 BR:-. 126397 × 10 ^-6 CR: 0.829424 × 10 ^-7 AP: 0.269913 × 10 ⁺⁰ BP: -.310065 × 10 ⁺¹ CP: 0.125716 × 10 ⁺⁰ r8 (display surface) INFINITY

[0061] Arrangement of each plane Surface XSC YSC ZSC ASC BSC CSC r1 0 0 0 0 0 0 r2 0 0.1 14 0 0 0 r3 0 3.695 11.7 35.728 0 0 r4 0 0.1 14 0 0 0 r5 0 0.1 17.5 0 0 0 r6 0 0.1 14 0 0 0 r7 0 -24.296 19.499 -98.937 0 0 r8 0 -25.225 20.034 -37.526 0 0

Example 4 Surface Number Curvature Radius Medium r1 (pupil surface) INFINITY AIR r2 (light beam selection surface) INFINITY PMMA r3 (reflection surface) INFINITY PMMA hologram Definition of two light beams HV1: REA HV2: VIR HX1: 0.000000 × 10 ⁺⁰ HY1:-. 930000 × 10 ⁺¹ HZ1:-. 195000 × 10 ⁺² HX2: 0.000000 × 10 ⁺⁰ HY2: 0.435556 × 10 ⁺⁶ HZ2:-. 276247 × 10 ⁺⁷ HWL: 532 Phase coefficient C2 ^{: -2.7403 × 10 -1 C3: -5.5899} × 10 -4 C5: 3.5457 × 10 -3 C7: 1.1443 × 10 -4 C9: 1.2053 × 10 -4 C10: 2.1687 × 10 -5 C12: -1.5075 × 10 - ⁴ C14: -5.4541 × 10 ^-4 C16: 1.1868 × 10 ^-5 C18: -3.7214 × 10 ^-5 C20: -2.5027 × 10 ^-4 C21: -9.9841 × 10 ^-7 C23: 5.8089 × 10 ^-6 C25: 6.6827 × 10 ^-6 C27: -4.6473 × 10 ^-5 C29: -1.821 × 10 ^-7 C31: 2.6129 × 10 ^-6 C33: 7.1404 × 10 ^-6 C35: -1.0668 × 10 ^-6 C36: 1.7421 × 10 ^-8 C38 : 1.4214 × 10 ^-8 C40: 6.8433 × 10 ^-7 C42: 1.7906 × 10 ^-6 C44: 8.8158 × 10 ^-7 C46: 3.7198 × 10 ^-9 C48: 1.0953 × 10 ^-8 C50: 8.3581 × 10 ^-8 C52: ^{1.9290 × 10 -7 C54: 1.2291 ×} 10 -7 C55: -7.0148 × 10 -11 C57: 4.0400 × 10 -10 C59: 9.0113 × 10 -10 C61: 3.7530 × 10 -9 C63: 7.7647 × 10 - ⁹ C65: 5.1387 × 10 ^-9 r4 (light flux selection surface) INFINITY PMMA r5 (second reflection surface) INFINITY PMMA r6 (first reflection surface) INFINITY PMMA r7 (incident surface) INFINITY PMMA r8 (display surface) INFINITY

Arrangement of each surface Surface XSC YSC ZSC ASC BSC CSC r1 0 0 0 0 0 0 r2 0 -1.5 16 0 2 0 r3 0 0.0467 16.4 30 0 0 r4 0 -1.5 16 0 0 0 r5 0 -1.5 19.8 0 0 0 r6 0 -1.5 16 0 0 0 r7 0 -21.316 36.342 -83.546 0 0 r8 0 -26.338 24.785 -57.550 0 0

Example 5 Surface Number Curvature Radius Medium r1 (pupil surface) INFINITY AIR r2 (light beam selection surface) INFINITY PMMA r3 (reflection surface) INFINITY PMMA hologram Definition of two light beams HV1: REA HV2: VIR HX1: 0.000000 × 10 ⁺⁰ HY1:-. 930000 × 10 ⁺¹ HZ1:-. 195000 × 10 ⁺² HX2: 0.000000 × 10 ⁺⁰ HY2: 0.435556 × 10 ⁺⁶ HZ2:-. 276247 × 10 ⁺⁷ HWL: 532 Phase coefficient C2 : -2.5943 × 10 ^-1 C3: -3.2624 × 10 ^-4 C5: 1.6372 × 10 ^-3 C7: 3.0074 × 10 ^-4 C9: -4.5208 × 10 ^-5 C10: -1.4408 × 10 ^-5 C12: 4.5938 × 10 ^-5 C14: -5.9452 × 10 ^-4 C16: -1.6161 × 10 ^-6 C18: 8.0915 × 10 ^-5 C20: -2.5984 × 10 ^-4 C21: 5.0639 × 10 ^-7 C23: -1.1377 × 10 ^-6 C25: ^{3.4244 × 10 -5 C27: -4.9979 ×} 10 -5 C29: 2.1833 × 10 -7 C31: -1.8584 × 10 -6 C33: 8.3435 × 10 -6 C35: -1.8062 × 10 -6 C36: -1.1090 × 10 - ⁸ C38: -4.0064 × 10 ^-8 C40: -5.6494 × 10 ^-7 C42: 1.3278 × 10 ^-6 C44: 9.1143 × 10 ^-7 C46: -5.3456 × 10 ^-9 C48: -1.2695 × 10 ^-8 C50:- 6.3208 × 10 ^-8 C52: 1.2463 × 10 ^-7 C54: 1.4644 × 10 ^-7 C55: 5.5275 × 10 ^-11 C57: -5.9780 × 10 ^-10 C59: -6.1101 × 10 ^-10 C61: -2.4014 × 10 ^-9 C63: 5.0146 × 10 ^{- 9} C65: 6.8781 × 10 ^-9 r4 (light flux selection surface) INFINITY PMMA r5 (second reflection surface) INFINITY PMMA r6 (first reflection surface) INFINITY PMMA r7 (incident surface) INFINITY PMMA r8 (display surface) INFINITY

Arrangement of each plane Surface XSC YSC ZSC ASC BSC CSC r1 0 0 0 0 0 0 r2 0 -1.5 16 0 0 0 r3 0 -0.455 16.33 30 0 0 r4 0 -1.5 16 0 0 0 r5 0 -6.8 19.8 4 0 0 r6 0 -1.5 16 0 0 0 r7 0 -22.917 49.152 -81.318 0 0 r8 0 -29.225 21.517 -56.721 0 0

The image display means in the claims corresponds to the image display element in the embodiment.

[0067]

As described above, according to the present invention,
It is possible to provide an information display optical system that can have a thin and compact configuration, can obtain a good image even at a wide display angle of view, and can also perform natural see-through observation of the outside world.

[Brief description of the drawings]

FIG. 1 is a graph illustrating diffraction wavelength widths of a transmission type and a reflection type hologram.

FIG. 2 is a graph (monochromatic) showing an intensity relationship between reflected light and transmitted light with respect to the wavelength of incident light.

FIG. 3 is a graph (color) showing an intensity relationship between reflected light and transmitted light with respect to the wavelength of incident light.

FIG. 4 is a longitudinal sectional view schematically showing the configuration of the information display optical system according to the first embodiment.

FIG. 5 is a longitudinal sectional view schematically showing a configuration of an information display optical system according to a second embodiment.

FIG. 6 is a longitudinal sectional view schematically showing a configuration of an information display optical system according to a third embodiment.

FIG. 7 is a longitudinal sectional view schematically showing a configuration of an information display optical system according to a fourth embodiment.

FIG. 8 is a longitudinal sectional view schematically showing a configuration of an information display optical system according to a fifth embodiment.

FIG. 9 is a longitudinal sectional view schematically showing a configuration of an information display optical system according to a sixth embodiment.

FIG. 10 is a longitudinal sectional view schematically showing a configuration of an information display optical system according to a seventh embodiment.

FIG. 11 is an external view of an example of a head-mounted image display device to which the present invention is applied.

FIG. 12 is a longitudinal sectional view of an information display optical system portion of the head mounted image display device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Prism 2 Pupil 3 Image display element 4, 7 Deflection correction member 5 Condenser lens 6 Light source

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H04N 5/64 511 H04N 5/64 511A F-term (Reference) 2H049 CA01 CA05 CA08 CA09 CA17 CA22 2H087 KA07 KA14 LA12 RA05 RA08 RA13 RA41 RA45 RA46 TA02 TA06 UA01 5G435 AA01 BB19 DD02 GG01 GG02 GG03 LL07 9A001 BB06 HH34 KK16

Claims (14)

[Claims] 1. At least two elements arranged opposite to each other
A light-flux selecting surface for selectively transmitting and reflecting at least one of the reflecting surfaces disposed opposite to each other according to an incident angle, comprising two prisms each having one reflecting surface and another reflecting surface; Wherein each of the image lights from the respective image display means incident on each of the prisms is reflected between the reflecting surfaces arranged opposite to each other, subsequently reflected on the other surface, and further An information display optical system characterized in that each light is guided to one pupil of an observer after passing through a light beam selection surface. 2. The information display optical system according to claim 1, wherein the other reflection surface has an optical power for enlarging and projecting the image light onto a pupil of the observer. 3. The apparatus according to claim 1, wherein the other reflection surface is arranged to be inclined toward the prism incident surface.
Information display optical system described in 1. 4. The information display optical system according to claim 1, wherein the display areas of the image lights are connected to each other. 5. The apparatus according to claim 1, further comprising a deflection correcting member for correcting the deflection of external light passing through the prism.
An information display optical system according to claim 4. 6. The information display optical system according to claim 1, wherein said another reflection surface is a hologram surface composed of a reflection hologram. 7. The information display optical system according to claim 6, wherein said hologram is of a volume type and a phase type. 8. The information display optical system according to claim 6, wherein the hologram surface is a flat surface. 9. The information display optical system according to claim 1, wherein the reflection surfaces arranged opposite to each other are substantially parallel to each other. 10. The apparatus according to claim 1, wherein the reflection surfaces arranged opposite to each other form an angle that is open to a side where the image light enters the prism. Information display optical system. 11. The information display optical system according to claim 5, wherein the reflection between the reflection surfaces arranged opposite to each other is total reflection. 12. The information display optical system according to claim 1, wherein at least one of the reflection surfaces arranged opposite to each other is a curved surface. 13. An optical element or an optical element comprising: an incident surface; a first reflecting surface; a light beam selecting surface that selectively reflects and transmits light according to an incident angle; and a second reflecting surface that converges incident light. In the system, the first reflection surface and the light beam selection surface are disposed to be opposed or substantially opposed to each other, and the incident light is transmitted through the light beam selection surface after passing through the second reflection surface. Optical system. 14. An information display device comprising an information display section and the optical element or optical system according to claim 13.