KR100254730B1 - Observation apparatus - Google Patents

Abstract

PURPOSE: An observation device is provided to make an observation optical system guiding the original picture of an LCD(Liquid Crystal Display) to the eyeballs of an observer. CONSTITUTION: An observation device includes a display unit(4) for forming an original picture, a first surface(5) transmitting the light of the original picture, a second surface(1) being the curved surface totally reflecting the light transmitted through the first surface and a third surface reflecting the light totally reflected on the second surface. Also, the first or the third surface is formed as the surface in a prism(3a). Then, the light reflected on the third surface is transmitted through the second surface and guided to the eyeballs.

Description

Observation apparatus {OBSERVATION APPARATUS}

The present invention relates to an observation optical system, and more particularly to an optical system suitable for a device called a head-up display or an eyeglass display.

Background Art [0002] Conventionally, a display device in which a CRT or a liquid crystal display (LCD) is disposed near the head of an observer and the image formed by the CRT and the LCD can be observed has been continued. For example, there are U.S. Patent Nos. 4,081,209 and 4,969,724, Japanese Patent Laid-Open Nos. 58-78116, H2-297516 and H3 3-101709. Japanese Patent Laid-Open No. Hei 3-101709 describes a relatively easy-to-view observation apparatus of a true image type for re-imaging of an original image. However, since an optical lens for reimaging is used, considerable enlargement is inevitable.

On the other hand, US Patent Publication Nos. 4,081,209 and 4,969,724, Japanese Patent Laid-Open Publication Nos. 58-78116 and 2-297516 are slightly different in terms of being easy to see, but in view of miniaturization, they are advantageous to observe virtual images. A type observation device is described.

In the latter type of observation device, it can be said that the size of the device can be miniaturized as compared with the actual type, but it cannot be said that it is enough. Japanese Patent Laid-Open No. 58-78116 is an example of relatively miniaturization in the prior art, but the thickness in the optical axis direction of the eye is also thick. Moreover, it is described that optical distortion, astigmatism, coma, etc. generate | occur | produce in the observed image. The related art is also described in US patent application Ser. No. 08 / 317,529.

It is an object of the present invention to provide a compact and thin observation optical system in view of such a point.

Moreover, it aims at providing the observation optical system with few aberrations.

According to a feature of the invention, the above objects can be attained by an optical means having display means for displaying information and curved surfaces for guiding light from the display means to the eye, wherein the optical means is an eye progression. In order in the direction, the light incidence plane for introducing the light, the curved surface for total reflection of the light, and the concave surface for the eye that reflects the light to the eye, with the result that the light reaches the eye through these curved surfaces and is well suppressed. A compact display device having aberration can be obtained.

Another object of the present invention is to provide a display device as described above having a line of sight detection system for controlling the display state of the display means.

1A and 1B show an optical path in an observation optical system of the present invention.

2A and 2B show a cross section and an optical path in the observation optical system of Numerical Example 1 of the present invention.

3A and 3B show a cross section and an optical path in the observation optical system of Numerical Example 2 of the present invention;

4A and 4B show a cross section and an optical path in the observation optical system of Numerical Example 3 of the present invention.

5A and 5B show a cross section and an optical path in the observation optical system of Numerical Example 4 of the present invention.

6 and 7 are optical cross-sectional views showing the basic principle of the observation optical system of the present invention.

8A and 8B are schematic diagrams showing the optical path of the observation optical system of the present invention.

9 is a schematic diagram showing an optical path of a gaze detection system used in the present invention.

10 and 11 are schematic diagrams showing a state when an observation car is mounted on the display device of the present invention.

12A and 12B are partially enlarged views of FIGS. 8A and 8B.

Fig. 13 is a partial schematic view of the vicinity of the prism member in the sixth embodiment of the present invention;

14 is a partial schematic view of the vicinity of the prism member in the seventh embodiment of the present invention;

Fig. 15 is a partial schematic view of the vicinity of the prism member in the eighth embodiment of the present invention;

Fig. 16 is a partial schematic view of the vicinity of the prism member in the ninth embodiment of the present invention;

17A and 17B are schematic diagrams showing optical paths of an observation system and a gaze detection system in Example 8 of the present invention;

18A and 18B are schematic diagrams showing optical paths of an observation system and a gaze detection system in a ninth embodiment of the present invention;

19A and 19B are partial schematic views of an observation optical system and an eye detection optical system, respectively, of the present invention;

20 is a flowchart showing the control procedure of the present invention.

21 is a schematic diagram showing a selectable display area in the present invention.

Fig. 22 is a schematic diagram showing a point for display area selection in the present invention.

23A and 23B are partial schematic views of an observation optical system and an eye detection optical system, respectively, of the present invention;

24 is a flowchart showing the control procedure of the present invention.

<Description of the symbols for the main parts of the drawings>

(0) … Pupil (1) ... total reflection (or transmission)

(2) ... concave mirror (3) ... prism member

(3a), (3A) ... first optical member (3b), (3B) ... second optical member

(4) ... indicating means (5) ... entrance face

(6) ... light incident surface (7) ... dichroic mirror

(8) ... imaging lens for eye detection (9) ... imaging element

(10) ... optical member (prism) (11). Reflective surface

(12). Light source 13. Sidewall

(14). Visual line detection circuit 15. Discrimination means

(16) Control means (101) ... observer

(102) ... light source means (103) ... eyeball

(104) ... optical axis (105) ... CD-ROM

(106) ... video camera

Other objects and features of the present invention will become apparent from the description of the following examples.

First, the basic principle of the display optical system of the present invention will be described with reference to FIGS. 1A, 1B, and 6. Reference numeral 4 denotes display means for displaying an image such as a character or a pattern that becomes an original image, and constitutes a known liquid crystal display (LCD) device, for example. Denoted at 3a is a first optical member for guiding light from the display means 4 to the observer's eye, and 3b is a second optical member. The light from the display means 4 first enters the first optical member 3a, and then totally reflects from the total reflection surface 1 on the eye side of the first optical member, concave toward the observer concave surface composed of a half mirror. Reflected by the mirror 2, it is transmitted through the first total reflection surface 1 and guided to the eye.

1A and 1B show optical path views from the head and temporal heads, respectively.

Since the concave mirror 2 consists of a half mirror, an observer can observe the image of the display means 4 superimposed on the exterior scenery. In the present embodiment, the superimposition device is provided, but the device may be provided only to observe the image display, in which case the concave mirror becomes a mirror.

In the present embodiment, such a configuration is included, including the embodiments described later, and thus an extremely thin display device having an optical thickness of about 10 mm to 15 mm is achieved. In addition, the field of view angle achieves a wide-angle field of view of about 16.8 degrees in the horizontal direction and about 11.4 degrees in the vertical direction.

In addition, in this embodiment, the observer's surface is used as the total reflection surface and the transmissive surface, and the concave mirror 2 is used as the factor for achieving such miniaturization and wide angle, and the optical performance satisfactorily. Although it is considerably eccentric with respect to this, in addition to this, as shown in the numerical example described later, the total reflection surface is a curved surface, in particular, a curved surface having different optical power by an azimuthal angle, or this concave mirror ( Each of the factors such as the optical power given by the azimuth in 2) is greatly contributed.

In particular, by giving the concave mirror 2 optical power at an azimuth angle, the eccentric aberration generated by the concave mirror itself being eccentric can be sufficiently eliminated. In addition, the total reflection surface is similarly configured to correct the aberration generated by the concave mirror. Thereafter, the folding direction of the light is called the mother line direction and the direction orthogonal to this is called the meridian direction. In this embodiment, the angle of view in the meridian direction is wide, and the concave mirror has a relatively strong positive refractive power, which causes aberration. However, the aberration generated by this positive power is reversed in the meridian section of the total reflection surface. It gives negative optical power and corrects this. In particular, when looking from the meridian cross section and following the optical path from the display device side or the observer's eye side, the negative refractive power, positive refractive power (concave mirror), negative refractive power, and each surface perform their functions, and thus the symmetrical refractive power. It adopts power arrangement that it is arranged and is easy to remove aberration.

In order to shorten the thickness of the eye in the optical axis direction, it is preferable to set each element so that the optical system 3 is erected. Specifically, referring to FIG. 7, the tangent at the vertex of the total reflection surface 1, The angle (tilt angle) of the line perpendicular to the optical axis of the eye

Α | ≤20 °

You just need to satisfy By exceeding this range, the thickness in the optical axis direction becomes thicker and larger. In addition, when the image is superimposed on the landscape, it is not preferable because the tilt of the optical member is increased, which causes distortion of the landscape itself.

And more preferably

-15 ° ≤α≤5 °

If you satisfy. If the lower limit is exceeded, it can be thinned in a direction parallel to the optical axis of the eyeball, but the torsion becomes large. If the upper limit is exceeded, the thickness in the direction parallel to the optical axis of the eyeball becomes thick, and the entire prism weight becomes heavy, which is undesirable.

In addition, in the present embodiment, since the total reflection surface faces the concave surface toward the eyeball, the outer light incidence surface 6 also gives a curved surface having substantially the same shape as this to prevent the landscape from twisting.

Next, the concave mirror 2 is considerably eccentric with respect to the optical axis of the eye, and eccentric aberration occurs in this plane. However, in order to remove this eccentric aberration, the total reflection surface is used, and the concave mirror 2 adopts a surface (toric or anamorphic surface) different in curvature by azimuth as described above. Research is being conducted to suppress eccentric aberrations well. An aspherical surface (toric aspherical surface or anamorphic aspherical surface) is preferably used for these surfaces to obtain extremely good optical performance.

When the folding direction of the light beam is the busbar direction (y direction) and the direction perpendicular to these is the meridian direction (x direction), each surface is set so that the optical power varies depending on the azimuth angle. When the focal length at the paraxial axis in each direction is almost constant, i.e., the paraxial focal length at each electric field in the busbar cross section and the meridian cross section is f _x , f _y .

0.9 <| f _y / f _x | <1.1

It is desirable to satisfy.

In addition, the total reflection surface (or transmission surface) or the concave mirror is set so that the optical power is different according to the difference in the azimuth angle as described above, so as to suppress the eccentric aberration. If the paraxial curve radius is r _y , r _x

R _x | <| r _y |

This can be satisfied.

In the present embodiment, the bus bar direction is a folding direction, and the concave mirror 2 is largely tilted (eccentric) in this direction in order to achieve a small size, so that eccentric aberration occurs more in this bus bar direction than in the meridian direction. On the other hand, the optical power in the busbar cross section is made weaker than the power in the meridian cross section, that is, the paraxial curvature radius in the busbar direction is lengthened as indicated by the conditional expression to suppress the occurrence of eccentric aberration in the busbar direction. I have to.

And preferably the relationship between their curvature

R _x / r _y | <0.85

It is good to set it to satisfy. If it exceeds this range, the occurrence of eccentric aberration is remarkably large.

On the other hand, as in Numerical Examples 2 to 4 shown later, when the incidence surface 5 is formed with a different optical power due to a difference in azimuth angle, it is inversely opposite to the previous conditional expression.

_{| R x |> | r y} |

Since the following conditional expression is satisfied, the occurrence of eccentric aberration can be suppressed.

Further, in order to correct the aberration better, when the paraxial curvature radii at the meridian cross-sections of the total reflection surface (or transmission surface) 1 and the concave mirror 2 are r _x2 , r _x3 ,

-2.0 <2f _x / r _x2 <-0.1 ....... (a)

-2.5 <2f _x / r _x3 <-0.5 ....... (b)

This can be set within the range of conditions.

When the lower limit of the formula (a) is exceeded, the curvature (part power) of the total reflection surface in the meridian direction becomes strong, and distortion correction becomes difficult. When the lower limit of the formula (b) is exceeded, the curvature (positive power) of the concave mirror in the meridian direction becomes stronger, which makes astigmatism correction difficult. On the other hand, since the curvature of the total reflection surface in the meridian direction exceeding the upper limit of equation (a) becomes a direction having positive power, it becomes difficult to satisfy the total reflection condition. Moreover, when the upper limit of Formula (b) is exceeded, the thickness of the direction parallel to the optical axis of the eyeball becomes thick in the direction of weakening of the forward power of the concave mirror in the meridian direction, which is not preferable to increase in size.

In addition, when the field focal length in the bus bar direction is f _y , the radius of curvature of the total reflection surface is r _y2 , and the radius of curvature of the concave mirror is r _y3 .

-1.0 <2f _y / r _y2 <0 ....... (c)

-2.5 <2f _y / r _y3 <-0.2 ....... (d)

You can set it to satisfy.

When the lower limit of the formula (c) is exceeded, the negative power of the total reflection surface in the bus bar direction becomes stronger, and it becomes difficult to correct the eccentric distortion. When the lower limit of the formula (d) is exceeded, the positive power of the concave mirror in the bus bar direction becomes stronger, and the occurrence of eccentric astigmatism becomes large. In addition, if the upper limit of the formula (c) is exceeded, the total reflection condition in the bus bar direction is in conflict, and if it exceeds this, it becomes difficult to satisfy the total reflection condition. In addition, equation (d) relates to the power of the bus bar concave mirror, and when the upper limit is exceeded, the power is weakened, so that the electric field extends in the bus bar direction and becomes large.

In the above description, the total reflection surface (or transmissive surface) 1 and the concave mirror 2 are described with the curvature as the center, but in the present embodiment, the concave mirror 2 is the busbar direction (y direction) from the optical axis of the eyeball. Is parallel to the original image (+) in Fig. 7 (Fig. 7). By doing so, the eccentric distortion in the bus bar direction is also suppressed small.

If this shift amount of parallel eccentricity (distance in the busbar direction from the optical axis of the eye to the vertex of the curved mirror) is E (see Fig. 7).

E≥2.5mm

By parallelizing the eccentric to satisfy the eccentric distortion can be suppressed. In addition, in Example 1 mentioned later, the value of this eccentricity E is set to 5.2 mm. However, as in the other examples, the aberration correction can be satisfactorily performed by increasing this amount E, and more preferably E≥23 mm. good.

Next, focusing on the incident surface 5, as shown in FIG. 7, the angle θβ formed between the original image surface, which is the display means in the bus bar direction, and the incident surface is

5 ° ≤θβ≤30 °

It is good to set it to satisfy. Below the lower limit, the incidence plane and the original image plane become parallel, which is not good because the original image becomes thick in a direction parallel to the optical axis of the eye. Conversely, if the upper limit is exceeded, the original image is perpendicular to the direction parallel to the optical axis of the eye.

In the present embodiment, the illumination of the original image is not shown, but it is assumed that backlight illumination or direct natural light is used. As described above, when the original image is perpendicular to the optical axis, natural light cannot be obtained efficiently in consideration of direct natural light illumination, and the virtual image obtained by the reflective optical system becomes dark. Therefore, in the present embodiment, daytime light with strong natural light is natural light, and nighttime light without natural light detects backlight light and external brightness and selectively uses natural light and backlight light.

By the way, the liquid crystal display element (LCD) is used for the display means 4 in which the original image is formed, but the whole apparatus is miniaturized. At this time, the optical axis of the image center of the original image and the chief ray of the emitted light emitting the original image (eyeball) Γ (see FIG. 7) formed by the central beam of the aperture when

Γγ≤10 °

If you satisfy. This is a condition necessary when using a liquid crystal device as the original image plane. In general, since the liquid crystal has a small viewing angle, the incident liquid is obliquely incident on the liquid crystal and the light emitted is dissipated. Therefore, a bright virtual image cannot be obtained unless light is incident and emitted as perpendicular to the liquid crystal plane as possible. Thus, by satisfying this conditional expression, a sufficient bright image can be observed.

2A to 5B show optical cross-sectional views of numerical examples 1, 2, 3, and 4 shown below, respectively. 2A and 2B, a toric aspheric surface is used for both the concave mirror and the total reflection surface. 3A and 3B use an anamorphic aspheric surface for both the concave mirror, the total reflection surface, and the light incident surface. 4A to 5B also use anamorphic aspherical surfaces on all surfaces.

In addition, in numerical examples 2 to 4 corresponding to Figs. 3A to 5B, the incidence surface 5 has a curvature in order to achieve even better aberration correction.

In addition, although acryl is used for all as optical members in a present Example, it goes without saying that you may use a glass material.

Next, the numerical value of the Example of this invention is shown below. TAL is a toric aspheric surface, and AAL is an anamorphic aspheric surface.

The definition of TAL is

Where i denotes the face number.

Also, the definition of AAL is

+ AR _i {(1 + AP _i ) y ² + (1-AP _i ) x ² } ² + BR _i {(1 + BP _i ) y ² + (1-BR _i ) x ² } ³

+ CR _i {(1 + CP _i ) y ² + (1-CP _i ) x ² } ⁴ + DR _i {(1 + DP _i ) y ² + (1-DP _i ) x ² } ⁵

Where i denotes the face number.

Each A _i , B _i ,.. Are aspheric coefficients, respectively.

In addition, although the surface which differs in refractive power by the azimuth angle was employ | adopted in the Example shown below at least in the total reflection surface, this surface can also be comprised as a rotationally symmetric spherical surface or an aspherical surface.

Example 1

r _y1 [mm] r _x1 [mm] y, z

Busy curvature radius Meridian curvature Radius Vertex coordinates Bus direction Tilt angle

i = 1 ∞ (0, 0) 0

2 -548.019 -74.077 (-0.05, 19.80) T A L 0 Within prism

3 -57.595 -40.526 (5.10, 29.14) T A L -22 within prism

4 -548.019 -74.077 (-0.05, 19.80) T A L 0 Within prism

5 ∞ (18.58, 28.07) in a 68.90 prism

6 ∞ (21.38, 29.15) 51.17

K ₂ , K ₄ A ₂ , A ₄ B ₂ , B ₄ C ₂ , C ₄ D ₂ , D ₄

(TAL2,4) 613.869 -0.473E-5 0.326E-7 -0.940E-10 0.991E-13

K ₃ A ₃ B ₃ C ₃ D ₃

(TAL3) -1.360 0.345E-5 -0.301E-7 0.944E-10 -0.113E-12

Refractive index of the prism (d line) 1.49171 Mother-of-the-field f _y = 21.07mm

Prism's (d line) Abbe's 57.4 Meridian Focal Length f _x = 21.86mm

(Numeric data)

α = -1.8 ° E = 5.2 mm

F _y / f _x | = 0.96 γ = 1.36

R _x / r _y | = 0.7 β = 17.7

2f _x / r _x2 = -0.59

2f _x / r _x3 = -1.08

2f _y / r _y2 = -0.08

2f _y / r _y3 = 0.73

Example 2

r _y1 [mm] r _x1 [mm] y, z

Busy curvature radius Meridian curvature Radius Vertex coordinates Bus direction Tilt angle

i = 1 ∞ (0, 0) 0

2 -2158.074 -32.224 (0.60, 19.83) AAL -10.55

3 -63.157 -32.870 (34.76, 30.90) AAL within 15.81 prism

4 -2158.074 -32.224 (0.60, 19.83) AAL -10.55 within prism

5 72.108 1049.744 (14.82, 29.00) AAL 53.74 within prism

6 ∞ (17.03, 30.62) 42.91

(AAL2, 4) K _y2,4 K _x2,4 AR _2,4 BR _2,4 CR _2,4 DR _2,4

-13763.5 -3.896 -0.170E-4 0.401E-7 -0.154E-9 0.223E-12

AP _2,4 BP _2,4 CP _2,4 DP _2,4

-0.245 0.416E1-1 0.870E-1 0.203E-1

(AAL3) K _y3 K _x3 AR ₃ BR ₃ CR ₃ DR ₃

1.238 0.279 -0.317E-5 0.248E-8 -0.179E-11 0.608E-15

AP ₃ BP ₃ CP ₃ DP ₃

0.249 0.327E-2 -0.192E-1 0.181E-1

(AAA5) K _y5 K _x5 AR ₅ BR ₅ CR ₅ DR ₅

6.285 -1.33E-6 -0.114E-4 -0.402E-6 0.113E-8 -0.411E-10

AP ₅ BP ₅ CP ₅ DP ₅

0.273E1 0.155E1 0.160E1 -0.644

Refractive index of the prism (d line) 1.49171 Mother-of-the-field f _y = 23.20mm

Pride's (d line) Abbe's 57.4 Meridian Focal Length f _x = 24.09mm

(Numeric data)

α = -10.5 ° 2f _x / r _x2 = -1.5 2f _y / r _y3 = -0.73

F _y / f _x | = 0.96 2f _x / r _x3 = -1.47 E = 5.2mm

r _x | / r _y = 0.52 2f _y / r _y2 = -0.02 γ = 0.23 °

β = 10.8 °

Example 3

r _y1 [mm] r _x1 [mm] y, z

Busy curvature radius Meridian curvature Radius Vertex coordinates Bus direction Tilt angle

I = 1 ∞ (0, 0) 0

2 -3945.723 -49.792 (3.665, 20.415) AAL 0.04

3 -67.136 -38.803 (36.403, 32.01) AAL within 14.60 prism

4 -3945.723 -49.792 (3.665, 20.415) within AAL 0.04 prism

5 123.302 843.030 (19.610, 28.357) AAL 61.72 within prism

6 ∞ (22.402, 29.859) 52.54

(AAL2, 4) K _y2,4 K _x2,4 AR _2,4 BR _2,4 CR _2,4 DR _2,4

7202.73 -7.709 -0.142E-7 0.379E-7-0.154E-9 0.198E-12

AP _2,4 BP _2,4 CP _2,4 DP _2,4

-0.183 0.710E-1 0.514E-1 0.203E-1

(AAL3) K _y3 K _x3 AR ₃ BR ₃ CR ₃ DR ₃

1.066 0.193 -0.222E-5 0.321-8 -0.188E-11 0.461E-15

AP ₃ BP ₃ CP ₃ DP ₃

0.390 0.586E-1 -0.185E-1 -0.222E-1

(AAA5) K _y5 K _x5 AR ₅ BR ₅ CR ₅ DR ₅

-85.544 916252 -0.913E-6 -0.204E-9 0.117E-13 -0.227E-10

AP ₅ BP ₅ CP ₅ DP ₅

0.989E1 0.128E1 0.128E2 -0.952E-1

Refractive index of the prism (d line) 1.49171 Mother-of-the-field f _y = 23.71mm

Prism's (d line) Abbe's 57.4 Meridian Focal Length f _x = 23.70mm

(Numeric data)

α = 0.05 ° 2f _x / r _x2 = -0.95 2f _y / r _y3 = -0.71

F _y / f _x | = 1.0 2f _x / r _x3 = -1.22 E = 25.6mm

r _x | / r _y = 0.58 2f _y / r _y2 = -0.01 γ = 1.97 °

β = 15.5 °

Example 4

r _y1 [mm] r _x1 [mm] y, z

Busy curvature radius Meridian curvature Radius Vertex coordinates Bus direction Tilt angle

i = 1 ∞ (0, 0) 0

2 -3752.581 -50.580 (2.85,23.13) AAL 0 Within Prism

3 -66.938 -38.651 (36.37, 34.72) AAL 14.15 In Prism

4 -3752.581 -50.580 (2.85, 23.13) AAL 0 Within Prism

5 306.125 1095.447 (18.59, 31.48) AAL 69.84 within a prism

6 ∞ (21.46, 32.54) 51.20

(AAL2, 4) K _y2,4 K _x2,4 AR _2,4 BR _2,4 CR _2,4 DR _2,4

-33820.5 -11.350 -0.144E-4 0.398E-7 -0.153E-9 0.201E-12

AP _2,4 BP _2,4 CP _2,4 DP _2,4

-0.152 0.730E-1 0.494E-1 0.255E-1

(AAL3) K _y3 K _x3 AR ₃ BR ₃ CR ₃ DR ₃

1.063 0.127 -0.225E-5 0.326E-8 -0.188E-11 0.474E-15

AP ₃ BP ₃ CP ₃ DP ₃

0.372 0.568E-1 -0.168E-1 -0.208E-1

(AAA5) K _y5 K _x5 AR ₅ BR ₅ CR ₅ DR ₅

745.334 -651374 -0.656E-6 0.124E-6 0.474E-12 -0.972E-11

AP ₅ BP ₅ CP ₅ DP ₅

0.837E1 -0.273 0.563E1 -0.538

Refractive index of the prism (d line) 1.49171 Mother-of-the-field f _y = 23.09mm

Prism's (d line) Abbe's 57.4 Meridian Focal Length f _x = 23.09mm

(Numeric data)

α = 0 ° 2f _x / r _x2 = -0.91 2f _y / r _y3 = -0.69

F _y / f _x | = 1.0 2f _x / r _x3 = -1.19 E = 33.5mm

r _x | / r _y = 0.58 2f _y / r _y2 = -0.01 γ = 1.52 °

β = 18.6 °

As described above, according to the present invention, the horizontal angle of view ± 6.8 °, the vertical angle of view ±

A spectacle-type display with a wide field of view (high magnification) of 11.4 ° and an extremely thin thickness of about 10 mm to 15 mm in a direction parallel to the optical axis of the eye could be developed. In addition, bright and good optical performance can be obtained. Furthermore, by making the concave mirror the transflective surface, it is possible to superimpose a virtual image of a bright original image without distorting the landscape.

In addition, although the present invention is set to a wide field of view angle, the use of the present invention by setting to a narrower field of view angle can be made thinner. This is because the thickness of the present invention is determined by the area of view.

In the following embodiment, the optical system relating to the display of the head-up display device will be described in principle. Next, the apparatus further equipped with the line of sight detection function based on the optical system mentioned above is demonstrated.

8A is a partial cross-sectional view showing an optical path of an observation system and a gaze detection system according to an embodiment of the present invention, while FIG. 9 is a partial plan view of the system shown in FIGS. 8A and 8B, and FIG. 10 and 11 are schematic diagrams when the apparatus of the present invention is mounted on the head of an observer.

In the figure, reference numeral 101 denotes an observer, 4 denotes display means, for example, a liquid crystal display element, and displays image information of a visible region. The display means 4 displays the video information on the basis of signals from the video information supply means such as the CD-ROM 105 or the video camera 106. Reference numeral 10 denotes an optical member made of a transparent parallel plane plate, and a dichroic mirror 7 is provided inside the beam splitter for passing visible light and reflecting infrared light. Instead of the dichroic mirror (7), a simple half mirror may be used.

(3) is a prism member, which consists of a toric aspherical surface, part of the front surface (1) using total reflection, a back surface (6) made of a transparent or non-transparent plane or curvature, and a half installed in the prism member (3). It has the concave surface 2 which consists of the toric aspherical surface of permeation | transmission or specular reflection, and the incident surface 5. 104 is an optical axis (center axis), which coincides with the optical axis of the eyeball 103. Each element in the optical path from the display means 4 to the eyeball 103 constitutes an observation system for observing the virtual image of the video information displayed by the display means 4. Reference numeral 102 denotes a light source, and emits infrared light (a wavelength of around 800 nm) to the eyeball 103 so as to form a Pulkinye's image in order to detect the eye of the eyeball 103 of the observer 101.

(8) is an imaging optical system (imaging lens), and as shown in FIG. 2B, when the infrared light from the light source means 102 is irradiated to the eyeball 103 of the observer 101, The corneal reflection image and the imaging position of the pupil, etc. by the reflected light from the cornea are imaged on the surface of the image pickup device 9 such as a CCD via the dichroic mirror 7 of the prism member 3 and the optical member 10. have. The imaging lens 8 is provided independently of the observation system for observing the virtual image of the image information of the display means 4. A gaze detection system is configured to detect the line of sight of the eyeball 103 of the observer 101 by each element in the optical path leading to the image pickup device 9 via the eyeball 103 from the light source means 102. In the present embodiment, as described above, by setting each element of the observation system and the line of sight detection system, the miniaturization of the whole optical system when two systems are used is facilitated.

Next, the observation system which observes the virtual image of the video information displayed on the display means 4 using FIG. 8A and FIG. 8B is demonstrated. In this embodiment, the luminous flux is passed through the dichroic mirror 7 of the optical member 10 and introduced into the prism member 3 from the incident surface 5 based on the image information displayed on the display means 4. . After total reflection at the front surface 1 of the prism member 3, the light is reflected and collected at the concave surface 2 and passed through the front surface 1 to guide the eyeball 103 of the observer 101. At this time, by appropriately setting the curvature of the front surface 1 and the concave surface 2, the image information displayed on the display means 4 is not imaged in the middle, that is, the virtual image of the image information is not formed without forming a primary image formation surface. Is displayed in front of the observer 101.

As described above, in the present embodiment, the observation system is configured as a virtual image type, whereby the observer 101 observes the virtual image of the image information. In addition, in the present embodiment, by setting the curvature of the rear surface 6 with the concave surface 2 as the transflective surface and the rear surface 6 as the transmissive surface, the external image information and the image of the display means 4 The virtual images of information may be superimposed spatially so that both can be observed as the same attempt at the same field of view.

In the observation system of the present embodiment, as shown in Figs. 10 and 11, the display means displays the image information from the image information supply means such as the CD-ROM 105 or the video camera 106 which the observer 101 has. For example, autofocus (focusing on the video camera), electronic zoom (electrically expanding information in the visual direction), and zooming, using the eyeball information of the observer's eye obtained from the gaze detection system when displayed in (4). (The focal length f of the video camera is calculated to be the screen dimension extracted from the line of sight, and adjusted to the focal length), and the menu line selection (metering, flash panorama size, etc.) is controlled.

Next, the line of sight detection system which detects the line of sight of the eyeball 103 of the observer 101 is demonstrated using FIG. Infrared light from the light source means 102 illuminates the eyeball 103 of the observer 101. The infrared light reflected by the cornea of the eyeball 103 passes through the front surface 1 of the prism member 3, is reflected on the concave surface 2, totally reflected on the front surface 1, and then exits from the incident surface 5 The optical member 10 is guided. The light is reflected by the dichroic mirror 7 of the optical member 10 and subsequently totally reflected by the surface 10a of the optical member 10 and then incident on the imaging device 9 by the imaging lens 8.

The imaging lens 8 forms a corneal reflection image of the eyeball 103 and an image of the eyeball 103 such as a pupil on the image pickup device 9 surface. The gaze of the eyeball 103 is detected using the signal from the imaging device 9.

As the detection method of the eyeball of the eye in this embodiment, for example, the method disclosed in Japanese Patent Laid-Open No. Hei 1-274736, Japanese Patent Laid-Open No. 3-11492 or the like which was first proposed by the present applicant is used. have.

12A and 12B are schematic sectional views of the prism member 3 used in this embodiment. In these figures, the case where the prism member 3 is used as an observation system is shown, but when the prism member 3 is used as an eye detection system, the optical path is reversed only, and the optical action is the same. The light beam 4a generated perpendicularly from the display surface of the display means 4 is incident on the front surface 1 of the toric aspheric surface via the incidence surface 5 of the prism member 3 with an incident angle of 43 degrees or more on the front surface 1. I am making a total reflection at The light beam 4a totally reflected from the front surface 1 is reflected at the incidence angle of 43 degrees or less on the concave surface 2 formed of the toric aspherical surface, and is emitted from the front surface 1.

The front surface 1 has a curvature so as to perform total reflection in one part and transmit in another part. Thereby, it is equivalent to having two curved surfaces, and it combines with the concave surface 2, and comprises the reflection optical system which has three curvature as a whole. As a result, the focal length of the optical system is shortened (20 to 25 mm in the numerical example described later), and the optical system can be miniaturized.

In the present embodiment, the toric or toric aspherical surface or anamorphic aspherical surface having different refractive powers according to the azimuth angle, that is, the curvature by the azimuth angle is different from the observation system and the gaze detection system. Is being applied to. As a result, the eccentric aberration generated when the angle between the incident light and the reflected light on the concave surface 2 is increased to reduce the size of the optical system is well corrected.

The curvature of the front surface 1 and the back surface 6 is made to be a lens shape of a meniscus with a small refractive power when light passes through both surfaces. As a result, when observing image information such as an external landscape through the rear surface 6, the image information is observed satisfactorily.

In addition, within the meridian cross section, the front face 1 has negative refractive power, and the aberration generated by the positive refractive power of the concave surface 2 is corrected. Here, the meridian is a plane perpendicular to the plane including the light path from the image center of the display means in which light is guided to the eye center of the design value (ie, perpendicular to the ground of Figs. 12A and 12B).

In addition, in this embodiment, it is possible to have negative refractive power on the busbar cross section of the front surface 1, whereby the same effect can be obtained by making the meridian cross section a negative refractive power. Here, the busbar cross section is a plane including an optical path from the image center of the display means in which light is guided to the eye center of the design value (that is, in the ground of Figs. 12A and 12B).

As shown in Fig. 12B, the angle formed by the tangent L at the busbar section at the vertex of the front face 1 and the line m passing through the vertex of the front face 1 perpendicular to the optical axis 104 of the eyeball ( When the tilt angle)

Α | ≤20 ° ....... (1)

To be. As in the conditional expression (1), the angle α is made smaller than 20, thereby spatially superimposing image information such as the virtual image of the image information of the display means 4 and the external landscape, thereby reducing the distortion when observing both sides. In addition, the thickness of the prism in the optical axis direction is thinned.

Next, in the optical path from the display means 4 of the present embodiment to the eyeball 103, the above-described observation system and eye detection system having each element (incident surface 5, front surface 1, concave surface 2) The features will be described.

(2-1) In this embodiment, the imaging magnification β from the eyeball 103 of the imaging lens 8 to the imaging device 9 is

0.02 <｜ β ｜ <0.18 ........ (2)

I am doing it. If the upper limit of the conditional expression (2) is exceeded, the magnification of the eyeball becomes too large and the effective diameter of the image pickup device is increased. In addition, if the lower limit value of the conditional expression (2) is exceeded, the focal length of the line of sight detection system must be further shortened. As a result, the occurrence of aberration increases, and a good eye image cannot be obtained.

(2-2) When the focal lengths of the electric field of the busbar section and the meridian section in the observation system are f _y and f _x , respectively,

0.9 <| f _y / f _x | <1.1 ......... (3)

This condition is satisfied. As a result, the focal length of the electric field becomes substantially constant at any azimuth angle, thereby making it unnecessary to correct the aspect ratio of the busbar direction and the meridian direction of the video information displayed by the display means.

(2-3) When the paraxial curvature radii of the busbar section and the meridian section of the concave surface (2) are R _y and R _x , respectively,

| R _x | <| R _y | .......... (4)

This condition is satisfied. In order to make the observation system small, it is necessary to tilt the optical axis of the concave surface in the clockwise direction from the optical axis of the eye at the busbar section, and a large amount of eccentric aberration occurs. On the other hand, the meridian cross section has less eccentricity, so less eccentric aberration occurs. In this embodiment, as indicated by the conditional formula (4), the radius of curvature R _y of the busbar cross section is made larger than the radius of curvature R _x of the meridian cross section, i.e., the refractive power in the busbar direction is weaker than the refractive power in the meridian direction, so that Eccentric aberration is reduced.

In this embodiment, in order to correct the eccentric aberration, the condition (4) is preferably set as follows.

R _x / R _y | <0.85 ........... (5)

(2-4) When the incident surface 5 of the prism member 3 consists of a toric surface or an anamorphic surface, a condition is selected:

| R _y5 | <| R _x5 | ........ (6)

Where R _y5 and R _x5 are the radii of curvature at the busbar section and the meridian section, respectively. The incident surface 5 generates relatively small eccentric aberration in the busbar section. Thus, even if the concave surface 2 and the front surface 1 cannot be given a strong refractive power at the busbar cross section, the incident surface 5 gives a strong refractive power at the busbar cross section, so that the focal length is substantially constant at any azimuth angle in the whole system. Can be realized.

(2-5) A satisfactory optical performance is realized in the meridian section by giving negative refractive power to the total reflection area of the front surface 1, positive refractive power to the concave surface 2 and negative refractive power to the transmission area of the front surface 1. In the case where the incident surface 5 has refractive power, in order to cover the lack of positive refractive power in the busbar cross section in the whole system, it is preferably selected as positive in the bus cross section.

(2-6) A satisfactory optical performance is realized in the bus bar section by applying negative refractive power to the total reflection area of the front surface 1 and positive refractive power to the concave surface 2. In the case where the incident surface 5 has refractive power, since it is positively selected from the meridian cross section, the aberration at the meridian cross section can be reduced.

(2-7) In the meridian section, the following conditions are satisfied:

0.1 <｜ 2f _x / R _x1 | <2.0 ....... (7)

0.5 <｜ 2f _x / R _x2 | <2.5 ....... (8)

Here, R _x1 and R _x2 are the radius of curvature of the total reflection areas of the front surface 1 and the concave surface 2, respectively, and f _x is the focal length of the whole system. The upper limit of the conditions (7) and (8) corresponds to the stronger refractive power of the curvature, and the lower limit corresponds to the weaker refractive power. Above the upper limit of condition (7), the distortion aberration becomes difficult to correct, and below the lower limit, the overall reflection condition becomes difficult to be satisfied. In addition, above the upper limit of the condition (8), astigmatism becomes difficult to correct, and below the lower limit, the entire optical device becomes larger, especially with a great thickness in the direction parallel to the optical axis.

(2-8) In the busbar section, the following conditions are met:

0 <｜ 2f _y / R _y1 ｜ <1.0 .... (9)

0.2 <｜ 2f _y / R _y2 ｜ <2.5 ..... (10)

Here, R _y1 and R _y2 are the radius of curvature of the total reflection area of the front surface 1 and the concave surface 2, respectively, and f _y is the focal length of the entire system. The upper limits of conditions (9) and (10) correspond to the stronger refractive power of the curvature, while the lower limit corresponds to the weaker refractive power. Above the upper limit of condition (9), the eccentric twist aberration becomes difficult to correct, while below the lower limit, it becomes difficult to satisfy the total reflection condition. In addition, above the upper limit of the condition (10), eccentric astigmatism is greatly generated, and below the lower limit, the length of the entire lens increases and the whole optical system becomes undesirably bulky.

(2-9) The concave surface 2 is shifted in a parallel manner from the optical axis 104 of the eye toward the display means 4 in the busbar section (Y direction), so that the eccentric distortion of the busbar section can be suppressed. . The amount E of parallel shift (distance from the optical axis 104 to the apex of the concave surface 2, as shown in Fig. 12B) is chosen so as to satisfy 25 &lt; Can be modified satisfactorily.

(2-10) The tilt angle under condition (1) is maintained to satisfy the following in order to effectively compact the whole optical system:

-15 ° ≤α≤5 ° ......... (12)

Under the lower limit of the condition 12, the image information is significantly distorted, while on the upper limit, the prism member 3 becomes thicker in the direction of the optical axis 104.

13 to 16 are schematic views showing deformation of a part of the visual line detection apparatus in the vicinity of the prism member 3.

The embodiment shown in FIG. 13 has been described above in that the optical member 10 is provided between the observer's eye 103 and the prism member 3 by the corresponding positioning of the image lens 8 and the image sensor 9. It differs from an Example. This embodiment provides the advantage of accurate detection of visual lines since the eccentric plane is not included in the visual line detection apparatus.

In the embodiment shown in FIG. 14, the dichroic surface 7 is installed in an inclined manner inside the prism member 3 with corresponding positioning of the image lens 8 and the image sensor 9. This embodiment is characterized by a reduced number of parts leading to further compactization of the total optical device.

In the embodiment shown in FIG. 15, the optical member 10 is located farther than the prism member 3 from the eye 103. The concave surface 2 also includes a dichroic film that reflects visible light and transmits infrared light. The optical member 10 has an inclined reflecting surface 11 having semi-transmissive, total reflection or dichroic film, whereby the image lens 8 and the image sensor 9 are positioned. The installation state of the present apparatus on the observer's head is schematically illustrated in FIGS. 17A and 17B.

In the embodiment shown in Fig. 16, the optical member 10 constituting the parallel plane flat plate is mounted on the incident surface 5 of the prism member 3 to a dichroic mirror 7 which transmits visible light and reflects infrared light. Are replaced, and the image lens 8 and the image sensor 9 are thus positioned. The installation of the apparatus of the present invention on the observer's head is schematically illustrated in FIGS. 18A and 18B.

The display (display) apparatus utilizing the visual line detection apparatus of the above-described embodiment can be directly applied to the so-called head-up display apparatus.

Next, with reference to Figs. 8A, 8B and 9, numerical examples of the present embodiment, in which the elements of the apparatus are shown as follows:

(1) the eyeball 103 is selected as the origin (0,0) of the coordinate system;

(2) in a visual line detection apparatus for tracking light from the eyeball 103;

i = 1 eyeball

i = 2 front (1) (transparent)

i = 3 concave (2)

i = 4 front (total slope)

i = 5 incidence plane (5)

i = 6 incident surface of the optical member 10

i = 7 dichroic plane

i = 8

i = 9 exit surface of the optical member 10

incident surface of the i = 10 image lens

exit surface of the i = 11 image lens

i = 12 image sensor

In the observation device;

incidence plane of i = 8 image information

i = 9 Display surface of image information

(3) TAL represents a toric aspheric surface; ALL represents an anamorphic aspherical surface.

TAL is defined in the parent (Y-Z) section by the following aspherical formula;

Where i is the surface number and the spherical surface in the meridian (X-Z) section. AAL also

+ ARi {(1 + APi) y ² + (1-APi) X ² } ² + BRi {(1 + BPi) y ² + (1-BPi) x ² } ³

+ CRi {(1 + CPi) y ² + (1-CPi) X ² } ⁴ + DRi {(1 + DPi) y ² + (1-DPi) x ² } ⁵

Defined by, where i is a face number. Also in the present invention, AL represents a rotationally symmetric aspheric surface defined by:

Where i represents the number of faces. Vertex coordinates (Y, Z) are absolute coordinates when the eye vertex is taken as (0,0). The inclination angle of the busbar cross section represents the inclination angle of the optical axis of each surface with respect to the optical axis of the eyeball, and the angle is taken in the positive counterclockwise direction. The reflecting surface (including the total reflecting surface) is indicated by the suffix M. nd and v d represent the refractive index and Abbe's number for d-line, respectively.

Numerical Example 5

(Visual line detection device)

r _y1 r _xi

Of meridian cross section

Radius of curvature radius of curvature

Vertex coordinate y, z angle of inclination of busbar section

i = 1 ∞ (0, 0) 0 ° eye

when nd = 1.49171, νd = 57.4

i = 2 -514.575 -52.805 (0, 21.15) 0 TAL

when nd = 1.49171, νd = 57.4

i = 3 -63.546 42.575 (26.30, 35.96) -3.33 TAL-M

when nd = 1.49171, νd = 57.4

i = 4 -514.575 -52.805 (0, 21.15) 0 TAL-M

when nd = 1.49171, νd = 57.4

i = 5 ∞ (20.72, 28.06) 65.37

nd = 1.51633, νd = 64.1

i = 6 ∞ (21.18, 28.27) 65.37

nd = 1.51633, νd = 64.1

i = 7 ∞ (23.41, 28.20) 30.37 M

nd = 1.51633, νd = 64.1

i = 8 ∞ (21.18, 28.27) 65.37 M

nd = 1.51633, νd = 64.1

i = 9 ∞ (24.93, 20.09) -54.64

when nd = 1.49171, νd = 57.4

i = 10 -1.889 (26.90, 21.14) -54.64 AL

when nd = 1.49171, νd = 57.4

i = 11 1.426 (29.35, 19.41) -54.64 AL

i = 12 ∞ (30.51, 18.95) -51.60 Image sensor

Observation

nd = 1.51633, νd = 64.1

i = 8 ∞ (23.91, 29.52) 65.37

i = 9 ∞ (24.98, 30.01) 59.37 Image Information

(TAL, AL data)

TAL2, 4: K = 460.670, A = -0.227E-5, B = 0.179E-7, C = -0.453E-10, D = 0.429E-13

TAL3: K = 1.105, A = 0.709E-6, B = -0.273E-8, C = -0.191E-11, D = 0.631E-15

AL10: K = -3.858, A = 0.851E-2, B = -0.101, C = 0.149, D = -0.755E-1

AL11: K = -0.113, A = 0.195, B = -0.590, C = 0.471, D = -0.138

(1) α = 0 (5) | Rx1 / Rt1 | = 0.10 (8) 2fx / Rx2 = -1.09 (11) E = 26.3

(2) | β | = 0.10 | Rx2 / Ry2 | = 0.67 (9) 2fy / Ry1 = -0.04

(3) | fy / fx | = 1.00 (7) 2fx / Rx1 = -0.88 (10) 2fy / Ry2 = -0.36

Numerical Example 6

(Visual line detection device)

r _y1 r _xi

Of meridian cross section

Radius of curvature radius of curvature

Vertex coordinate y, z angle of inclination of busbar section

when nd = 1.49171, νd = 57.4

i = 1 ∞ (0, 0) for 0 ° eye nd = 1.49171, νd = 57.4

i = 2 -514.575 -52.805 (0, 21.15) when 0 TAL nd = 1.49171, νd = 57.4

i = 3 -63.546 42.575 (26.30, 35.96) -3.33 When TAL nd = 1.49171, νd = 57.4

i = 4 -514.575 -52.805 (0, 34.15) 0 TAL

i = 5 ∞ (0.37, 15) 45 M

when nd = 1.49171, νd = 57.4

i = 6 -1889 (-13.0, 37.15) 90 AL nd = 1.49171, v d = 57.4

i = 7 1.426 (-16.0, 37.15) 90 AL

i = 8 ∞ (-17.27, 37.15) 90 Image sensor

Observation

nd = 1.51633, νd = 64.1

i = 3 -63.546 42.575 (26.30, 35.96) -3.33 when TAL-M nd = 1.51633, νd = 64.1

i = 4 -514.575 -52.805 (0, 21.15) 0 TAL-M

nd = 1.51633, νd = 64.1

i = 5 ∞ (20.72, 28.06) 65.37

i = 6 ∞ (24.05, 29.59) 54.25 Image Information

(TAL, AL data)

TAL2, 4: K = 460.670, A = -0.227E-5, B = 0.179E-7, C = -0.453E-10, D = 0.429E-13

TAL3: K = 1.105, A = 0.709E-6, B = -0.273E-8, C = -0.191E-11, D = 0.631E-15

AL6: K = -3.858, A = 0.851E-2, B = -0.101, C = 0.149, D = -0.755E-1

AL7: K = -0.113, A = 0.195, B = -0.590, C = 0.471, D = -0.138

(1) α = 0 (5) | Rx1 / Rt1 | = 0.10 (8) 2fx / Rx2 = -1.09 (11) E = 26.3

(2) | β | = 0.5 | Rx2 / Ry2 | = 0.67 (9) 2fy / Ry1 = -0.04

(3) | fy / fx | = 1.00 (7) 2fx / Rx1 = -0.88 (10) 2fy / Ry2 = -0.36

[Example 7]

(Visual line detection device)

r _y1 r _xi

Of meridian cross section

Radius of curvature radius of curvature

Vertex coordinate y, z angle of inclination of busbar section

i = 1 ∞ (0, 0) 0 ° eye

when nd = 1.49171, νd = 57.4

i = 2 -2158.074 -32.224 (0.60, 19.85) -10.55 AAL nd = 1.49171, νd = 57.4

i = 3 -63.157 -32.870 (34.76, 30.92) 15.81 AAL-M nd = 1.49171, νd = 57.4

i = 4 -2158.074 -32.224 (0.60, 19.85) -10.55 AAL-M nd = 1.49171, νd = 57.4

i = 5 72.108 1049.744 (14.82, 29.02) 53.74 AAL nd = 1.49171, νd = 57.4

i = 6 ∞ (14.98, 29.14) 53.74

nd = 1.51633, νd = 64.1

i = 7 ∞ (17.19, 29.51) 18.74 M nd = 1.51633, v d = 64.1

i = 8 ∞ (14.98, 29.14) 53.74 M nd = 1.51633, νd = 64.1

i = 9 ∞ (20.31, 21.88) -66.27 nd = 1.51633, νd = 64.1

i = 10 -1.889 (22.03, 23.31) -66.27 AL nd = 1.49171, νd = 57.4

i = 11 1.426 (24.77, 22.10) -66.27 AL nd = 1.49171, νd = 57.4

i = 12 ∞ (25.96, 21.91) -63.23 Image sensor

Observation

nd = 1.51633, νd = 64.1

i = 8 ∞ (17.40, 30.91) 53.74

i = 9 ∞ (18.21, 31.50) 44.74 Image Information

(AAL, AL data)

AAL2, 4:

Ky = -13763.5, AR = -0.170E-4, BR = 0.406E-7, CR = -0.154E-9, DR = 0.223E-12

Kx = -13.896, AP = -0.245, BP = 0.416E-1, CP = 0.870E-1, DP = -0.203E-1

AAL3:

Ky = 1.238, AR = -0.3170E-5, BR = 0.240E-8, CR = -0.179E-11, DR = 0.608E-15

Kx = 0.279, AP = -0.249, BP = 0.327E-2, CP = 0.192E-1, DP = 0.181E-1

AAL5:

Ky = 6.825, AR = -0.114E-4, BR = 0.402E-6, CR = 0.113E-8, DR = -0.411E-10

Kx = -1.33E + 6, AP = 0.273E + 1, BP = 0.155E + 1, CP = 0.160E + 1, DP = -0.644

AL10: K = -3.858, A = 0.851E-2, B = -0.101, C = 0.149, D = -0.755E-1

AL11: K = -0.113, A = 0.195, B = -0.590, C = 0.471, D = -0.138

(1) α = -10.5 (5) | Rx1 / Rt1 | = 0.01 (8) 2fx / Rx2 = -1.47 (11) E = 34.8

(2) | β | = 0.12 | Rx2 / Ry2 | = 0.52 (9) 2fy / Ry1 = -0.02

(3) | fy / fx | = 0.96 (7) 2fx / Rx1 = -1.5 (10) 2fy / Ry2 = -0.73

Numerical Example 8

(Visual line detection device)

r _y1 r _xi

Of meridian cross section

Radius of curvature radius of curvature

Vertex coordinate y, z angle of inclination of busbar section

i = 1 ∞ (0, 0) 0 ° eye

when nd = 1.49171, νd = 57.4

i = 2 -9423.260 -47.769 (0.20, 38) 1.50 AAL nd = 1.49171, νd = 57.4

i = 3 -65.701 -36.469 (33.13, 29.99) 14.29 AAL-M nd = 1.49171, νd = 57.4

i = 4 -9433.260 -47.769 (0, 20.38) 1.50 AAL-M nd = 1.49171, νd = 57.4

i = 5 7188.930 -49.971 (16.33, 26.54) 62.55 AAL nd = 1.49171, νd = 57.4

i = 6 ∞ (19.89, 27.27) 21.55 M

when nd = 1.49171, νd = 57.4

i = 7 -1.889 (21.28, 20.34) -11.45 AL nd = 1.49171, νd = 57.4

i = 8 1.426 (21.88, 17.39) -11.45 AL

i = 9 ∞ -8.45 Image sensor

Observation

i = 7 ∞ (21.11, 29.03) 55.43 Image Information

(AAL, AL data)

AAL2, 4:

Ky = -361850, AR = -0.183E-4, BR = 0.381E-7, CR = -0.114E-9, DR = 0.153E-12

Kx = -13.802, AP = -0.317, BP = -0.602E-1, CP = 0.272E-1, DP = -0.211E-1

AAL3:

Ky = 1.227, AR = -0.209E-5, BR = 0.308E-8, CR = -0.190E-11, DR = 0.505E-15

Kx = 0.172, AP = 0.472, BP = 0.553E-1, CP = -0.265E-1, DP = 0.751E-2

AAL5:

Ky = 987000, AR = -0.871E-5, BR = -0.264E-6, CR = 0.469E-13, DR = 0.137E-11

Kx = -70.169, AP = 41.763, BP = -0.395, CP = 0.183E + 2, DP = -0.988

AL7: K = -3.858, A = 0.851E-2, B = -0.101, C = 0.149, D = -0.755E-1

AL8: K = -0.113, A = 0.195, B = -0.590, C = 0.471, D = -0.138

(1) α = 1.5 (5) | Rx1 / Rt1 | = 0.005 (8) 2fx / Rx2 = -1.22 (11) E = 33.1

(2) | β | = 0.10 | Rx2 / Ry2 | = 0.56 (9) 2fy / Ry1 = -0.46

(3) | fy / fx | = 1.00 (7) 2fx / Rx1 = -0.93 (10) 2fy / Ry2 = -0.61

Numerical Example 9

(Visual line detection device)

r _y1 r _xi

Of meridian cross section

Radius of curvature radius of curvature

Vertex coordinate y, z angle of inclination of busbar section

i = 1 ∞ (0, 0) 0 ° eye

when nd = 1.49171, νd = 57.4

i = 2 -9538.246 -47.590 (0, 21.30) 7.28 AAL nd = 1.49171, νd = 57.4

i = 3 -65.6 -36.035 (32.96, 31.40) 14.67 AAL-M nd = 1.49171, νd = 57.4

i = 4 -9538.246 -47.590 (0, 21.30) 0.28 AAL-M nd = 1.49171, νd = 57.4

i = 5 225.188 727.642 (16.47, 28.45) 65.28 AAL nd = 1.49171, νd = 57.4

i = 6 ∞ (16.92, 28.60) 67.28 nd = 1.51633, νd = 64.1

i = 7 ∞ (19.15, 28.51) 35.28 M nd = 1.51633, νd = 64.1

i = 8 ∞ (16.92, 28.66) 67.28 M nd = 1.51633, νd = 64.1

i = 9 ∞ (19.69, 29.82) 67.28 M nd = 1.51633, νd = 64.1

i = 10 ∞ (23.55, 20.60) -167.72 nd = 1.51633, νd = 64.1

i = 11 1.889 (21.38, 20.05) -167.72 AL nd = 1.49171, νd = 57.4

i = 12 -1.426 (20.74, 17.12) -167.72 AL

nd = 1.51633, νd = 64.1

i = 13 ∞ (20.19, 16.01) -164.69 Image sensor

(Observation)

i = 8 ∞ (19.69, 29.82) 67.28

i = 9 ∞ (22.02, 29.17) 54.10 Image Information

(AAL, AL data)

AAL2, 4:

Ky = -387540, AR = -0.183E-4, BR = 0.378E-7, CR = -0.117E-9, DR = 0.158E-12

Kx = -20.897, AP = -0.300, BP = -0.548E-1, CP = 0.326E-1, DP = -0.228E-1

AAL3:

Ky = 1.213, AR = -0.224E-5, BR = 0.305E-8, CR = -0.190E-11, DR = 0.500E-15

Kx = 0.165, AP = -0.464, BP = 0.630E-1, CP = -0.251E-1, DP = 0.380E-2

AAL5:

Ky = 559.028, AR = -0.675E-5, BR = 0.182E-6, CR = 0.212E-12, DR = -0.189E-10

Kx = -99429.4, AP = 0.486E + 1, BP = -0.125E + 1, CP = 0.111E + 2, DP = -0.789

AL11: K = -3.858, A = 0.851E-2, B = -0.101, C = 0.149, D = -0.755E-1

AL12: K = -0.113, A = 0.195, B = -0.590, C = 0.471, D = -0.138

(1) α = 0.28 (5) | Rx1 / Rt1 | = 0.005 (8) 2fx / Rx2 = -1.26 (11) E = 33.0

(2) | β | = 0.11 | Rx2 / Ry2 | = 0.55 (9) 2fy / Ry1 = -0.005

(3) | fy / fx | = 1.00 (7) 2fx / Rx1 = -0.95 (10) 2fy / Ry2 = -0.69

As described above, according to the present invention, the observation apparatus is suitably compacted, and the observation apparatus is suitably used for observing the image information displayed by the visual line detection apparatus and the display means provided in a part of the observation apparatus for detecting the visual line of the observer. There is provided a display device such as a head mounted display having a visual line detection device that can be designed and controlled on the basis of the observation state of the image information displayed by the display means in the observation device and the visual line information.

Next, control of the display device utilizing the above-described visual line detection function will be described.

19A and 19B show respective optical paths of the observation apparatus and the visual line detection apparatus in the optical apparatus of the present invention.

The display means 4 displays an image, such as a character or a pattern, in visible light on its display surface, and the flat prism 10 is composed of two attachment prisms, and its bonding surface provides visible light for visual line detection. And a dichroic mirror for transmitting and reflecting infrared light. Prism 10 has sidewalls 13.

The first optical member 3A has a plane 5, a curved or aspherical surface 1, and a semi-transmissive or total reflection, spherical or aspherical surface 2a of positive refractive power.

In this embodiment, the face 2a is made of a half mirror. The second optical member 3B has a flat or curved surface 6 that is transparent or opaque, and a concave surface 2b composed of a semi-transparent or totally spherical or aspheric surface having the same shape as the surface 2a. The surface 2a of the first optical member 3A and the surface 2b of the second optical member 3B are attached to form one prism block 3. The attachment surface 2 forms a half mirror. In addition, an image lens 8 for visual line detection, an image sensor 9 made of a CCD, and an invisible (infrared) light are illuminated on the front of the eye E to detect the visual line of the eye E of the observer. The light source 12 is provided.

The visual line detection circuit 14 detects visual line information of the eyeball E. FIG. The discriminating means 15 determines whether the observer's visual line has been fixed for a predetermined time in substantially the same direction. The control means 16 receives an image signal from the image information source S and displays an image on the display surface of the display means 4 under the display state controlled from the discriminating means 15 based on the visual line information.

The prism 10 and the first optical member 3A constitute a part of the image observation optical device, and the image observation optical device and the second optical member 3B constitute a part of the observation optical device.

Next, referring to Fig. 19A, the operation of the observation optical device of this embodiment will be described. The control means 16 displays an image on the display surface of the display means 4 based on the signal from the image information source S. FIG. The light beam (visible light beam) from the image displayed on the display means 4 is introduced into the prism block 3 through the next surface 5 transmitted by the dichroic mirror 7 of the prism 10, It is totally reflected by face 1, then reflected and condensed by half mirror face 2, and exits face 1 to enter the observer's pupil 0. Thus, the virtual image Y of the image displayed on the display means 4 is formed in front of the viewer and can be observed by the viewer.

On the other hand, the light beam from the outer background G is introduced into the surface 6 of the prism block 3 and then transmitted by the half mirror 2, thus reaching the pupil of the observer who can observe the outer background. To come out of face (1). The observer thus observes the virtual image Y and the superimposed outer background displayed on the display means 4 within the same field of view.

Next, the operation of the visual line detection optical device of this embodiment will be described. In FIG. 17B, the light reflected and scattered by the front part of the observer's eyeball E and illuminated by infrared light from the light source 12 is introduced into the face 1 of the prism block 3 and then to the face 1. Is totally reflected and exits the face 5 to enter the prism 10. Next, it is reflected by the dichroic mirror 7 and totally reflected by the lower surface of the prism 10 and emerges from the surface 13. This is then transmitted by the image lens 8 for visual line detection to form an image of the front part of the eyeball on the image sensor 9. The light reflected by the cornea of the eyeball E forms a Purkinje's image, while the light scattered by the pupil forms an image of the pupil. The visual line detection circuit 14 calculates the direction of the visual line of the observer based on the furkin's image and the pupil image obtained from the image sensor 9. This detection can be achieved, for example, by the method disclosed in Japanese Patent Laid-Open No. 3-109029 to the applicant.

The light source 12, the first optical member 3A, the prism 10, the image lens 8, the image sensor 9 and the visual line detection circuit 14 constitute a part of the visual line detection means.

20 is a control sequence of the present invention for arbitrarily and selectively changing the size and position of the virtual image of the displayed image to be superimposed with the external image by the control means 16 of the present invention according to the visual line information of the observer's eyeball E. FIG. It is a flowchart showing. Fig. 21 is a schematic diagram showing the display area, i.e. the dimensions and positions of the display selectable in the image display on the display means 4; In the present embodiment, four display areas (1) to (5) can be selected, where (1) to (4) correspond to rectangular areas, respectively, each equal to one quarter of the display surface, while (5) corresponds to the complete display surface.

In the following, the steps of the flowchart are described. The figures on the right show the images provided to the viewer at each step.

In this embodiment, the direction of the observer's visual line is constantly detected.

Step 21: The switch is turned on to activate the function of the present invention. To this end, the switch mark is usually displayed at a predetermined position in the display surface during the image observation, and when the observer sees the virtual image of the switch mark for a predetermined time, the visual line detecting means and the discriminating means 15 detect such a viewing state and proceed to the next step. Starts the switching operation of the picture indicated by:

(1) The visual line detecting means detects the direction viewed by the observer. If the position of the visual line coincides with the switch mark or its vicinity, the discriminating means 15 stores the direction of the visual line as first visual line information in the memory, and the procedure goes to (2).

If the detection direction does not coincide with the switch mark, the discriminating means confirms that the observer does not want to switch the displayed phase, and the procedure does not proceed to (2).

(2) After the elapse of the predetermined time, the discriminating means 15 detects the direction observed by the observer by the visual line detecting means. If the detected direction coincides with the switch mark, the discriminating means 15 determines that the observer has seen the switch mark for a predetermined time, and sends a signal to the control means 16 to turn on the switch. The procedure then proceeds to step 22.

On the other hand, if the detection direction does not coincide with the switch mark, the procedure returns to (1).

By repeating the above steps, the switching operation for the displayed image is surely started when the viewer sees the switch mark for a predetermined time.

Step 22: When the switch is turned on, the control means 16 displays the five points shown in FIG. 22 on the display surface of the display means 4, for example. Thus, the observer sees the image 22a in FIG.

Step 23: Determine the display area.

The observer sees the point representing the desired display area for a predetermined time, and the visual line detecting means and the discriminating means 15 confirm the point of view for the predetermined time within the image 22a in the following procedure:

(1) The visual line detecting means detects the direction viewed by the observer, and the discriminating means 15 checks whether the detected direction coincides with any of the five points. If the detected direction coincides with any of the points, the detection direction or position is stored in the memory as the first time line information.

If the detected direction does not match any of the points, detection of the visual line continues until the visual line is detected at any of the points.

(2) After the elapse of the predetermined time, the discriminating means 15 detects the direction viewed by the observer by the visual line detecting means and obtains the second visual line information.

(3) The discriminating means 15 compares the detected direction of the visual line with the one corresponding to the point stored in the memory.

If the two directions coincide with each other, the discriminating means determines that the point corresponding to the detected direction is the point required by the observer for image display, sends corresponding information to the control means 16, and the procedure goes to step 24. Going forward

If the two directions do not coincide with each other, the sequence returns to (1).

The point of view of the observer is determined by repeating the above-described steps.

In this way, when an observer looks at a point for a predetermined time, the display area is uniquely determined corresponding to the point.

Step 24: The control means 16 changes the display size and position of the image and applies appropriate image processing to the image information to display the image in the display area determined in step 23. For example, when the point 5 shown in FIG. 21 is selected, the image is displayed at the full size of the display surface. When the point 4 is selected, the image size is changed to 1/4 of the display surface and displayed at its lower right side as indicated by 24a. However, the switch mark is displayed again separately. Thus the switching of the displayed phase is complete.

As described above, in this embodiment, the size and position of the virtual image of the displayed image to be superimposed may be changed only during the observation of the image and depending on the state of the trauma, only to a viewer's visual line at a specific position in the field of view without any manual operation. Satisfactory availability. In addition, in the present embodiment, the entire apparatus can be made compact by partial common use of an image observation optical device for observing a displayed image and a visual line detection optical device for visual line detection.

In the above embodiment, the display area can be selected in four ways, but it is also possible to further increase the freedom of selection effective for the observer. You can also manually perform a switch-on operation.

23A and 23B are schematic diagrams showing optical paths in an observation optical device and a visual line detection optical device, respectively, in another optical device of the present invention, wherein components like those in FIGS. 19A and 19B are the same number; Represented by

In this embodiment, Fig. 19A in that the conductive liquid crystal device (shielding member) 11 is installed outside the surface 6 of the second optical member to block the light beam or a part thereof entering the prism block 3 from the outside. And those shown in Fig. 19B. This blocking of the incoming light eliminates the overlap of the virtual image (Y) and the trauma of the displayed image, allowing a clear observation of the latter.

The prism 10, the first optical member 3A, etc. constitute a part of the image observation optical device, while the image observation optical device, the second optical member 3B and the liquid crystal device 11 are part of the observation optical device. Configure Further, the light source 12, the first optical member 3A, the prism 10, the image lens 8, the image sensor 9, and the visual line detection circuit 14 constitute a part of the visual line detection means.

The functions of the image observation and the visual line detection optical apparatus displayed by the image observation optical apparatus in this embodiment are the same as those in the above-described embodiment shown in Figs. 19A and 19B.

The following describes the control procedure of this embodiment with reference to the flowchart shown in FIG. The figure on the right side of the flowchart schematically illustrates the images provided to the observer at each step.

In this embodiment, the visual line direction of the observer is constantly detected.

Step 61: Switch on to operate the function of the present invention. As in the above-described embodiment, when the observer sees the virtual image of the switch mark displayed as a spot of a portion of the display image superimposed on the external image for a predetermined time, the visual line detecting means and the discriminating means 15 detect this viewing state. The switch operation of the display image is started.

Step 62: Insert the display size information of the display image. The control means 16 displays the virtual image of the display image 62a, for example for observation by the observer. The image includes, for example, a full-size rectangular display frame S1, a rectangular frame S2 1/2 of the size in the vertical and horizontal directions, and a rectangular frame S3 1/4 of the size. Each display frame has a mark that looks at the corner (the upper right corner in the example). When the observer sees the gaze marks belonging to the desired frame for a predetermined time, the visual line detecting means and the discriminating means 15 detect this gaze state and determine that the observer has selected the corresponding display size, where the display size Is determined and the corresponding information is supplied to the control means 16 (the procedure for this operation is the same as already described in step 23 of the above-described embodiment). Such order of selection from a limited number of display frames may result in a drastic setting of the display size even if fine adjustment of the display size is not possible. As an example, consider the case of selecting the frame S2.

Step 63: Insert the display position information of the display image. The control means 16 displays, for example, the virtual image of the display image 63a in which the full-size display surface is divided into an appropriate number of grid pattern areas by foaming with an external image. For a given time, the observer then looks at the desired image display position (e.g., indicated by 'X') in these areas. In response, the visual line detecting means and the discriminating means 15 determine the display position in the following order:

(1) The visual line detecting means detects the position seen by the observer in the grid pattern, and the discriminating means 15 stores the number of detection areas in the memory as the first visual line information.

(2) After the elapse of the predetermined time, the discriminating means 15 detects the position viewed by the observer in the grid pattern by the visual line detecting means, and the detected area number is taken as the second visual line information.

(3) The discriminating means 15 compares the detected area number with that stored in the memory. If the two area numbers coincide with each other, the discriminating means 15 determines this area as the image display area requested by the observer, and sends corresponding information to the control means 16. The procedure then proceeds to step 64.

If the two area numbers do not coincide with each other, the stored area numbers are replaced by the newly detected area numbers, and the procedure returns to (2).

The display position required by the viewer is determined by repeating the above steps. This order makes it possible to reliably write the positional information and avoid wrong input even if the observer's visual line is shifted somewhat as long as the observer sees the desired area for a predetermined time during the positional input of the positional information.

Step 64: The control means 16 determines whether it can be displayed around the designated display position by the observer of the designated size.

If such display is possible, the display area is determined accordingly and the procedure proceeds to step 65.

On the other hand, if the display image P1 around the designated position overflows the display surface as indicated by 64a, the procedure proceeds to step 66.

Step 66: Perform a calculation for shifting the display position of the display image P1 to determine the display area P2 that allows to maintain the specified size of the image P1 at the minimum shift of the display position.

Step 65: By shifting (changing) the transmittance of the liquid crystal device 11 to zero the control means 16 at the image overlapping portion as indicated by 65a, the external image in the portion is shielded and thus Avoid interference of external images with the determined image of the displayed image.

Step 67: The control means 16 applies appropriate image processing to the image information to change the size and position of the image display to display the image on the display areas determined in steps 64 and 66. FIG. The switch mark is displayed separately from the overlap area.

The switching of the display image is thus completed.

In the present embodiment, as described above, the size and position of the virtual image of the overlapping display image can be changed only by directing the viewer's visual line to a specific position in the field of view during the image observation and according to the state of the external image, and the overlapping portion The external image at is properly shielded by a shielding member. Thus, an observation optical device characterized by extremely satisfactory usability which allows clear observation of the virtual image Y of the display image without requiring any manual operation to change the display image is obtained.

The display size may also be displayed in an analog manner, for example, by displaying a linear pattern at one end corresponding to a full size image frame and at the other end corresponding to a 1/4 size image frame, and based on the position shown by the observer on the linear pattern. It can be entered by determining the display size required by. In this way, the observer can put the ratio of the display size to the maximum display size in a fairly precise manner.

In this embodiment, the grid pattern is displayed by writing of the display position, but such grid pattern display may be exempted.

According to the above-described configuration, the present invention utilizes the visual line of the observer, according to the observer's desire or external condition, the image displayed on the display surface during the observation of the virtual image at a specific position in the field of view or the observation of such virtual image spatially superimposed on the trauma. Provided is an observation optical device with excellent usability that can arbitrarily change the display size and position of the virtual image for observation.

In addition, since a part of the trauma in which the virtual image on the display overlaps can be shielded, an observation optical device capable of extremely clean observation of the virtual image is provided.

Claims (13)

Display means for forming an original image; A first surface that transmits light of an original image, a second surface that is a curved surface that totally reflects light transmitted through the first surface, and a third surface that reflects light totally reflected by the second surface, The first, second and third surfaces are observation devices having an observation optical system formed as a surface in a prism, wherein the light reflected by the third surface passes through the second surface to be guided to the eye. Observation device. 3. An observation apparatus according to claim 2, wherein said second surface has negative optical power in the meridian section. The observation device according to claim 1, wherein the third surface is a concave mirror surface, and the second surface has negative optical power in the meridian section. An observation apparatus according to claim 1, wherein the paraxial focal length is substantially constant in each direction of the entire system of the observation optical system. The observation device according to claim 1, wherein the first surface is a curved surface having optical power that varies according to an azimuth angle. The observation device according to claim 1, wherein the third surface is a curved surface having optical power that varies according to an azimuth angle. The observation apparatus according to claim 1, wherein the first surface is a curved surface having optical power that varies with the azimuth angle, and the third surface is a curved surface having optical power that varies with the azimuth angle. The observation device according to claim 1, wherein the second surface is a curved surface having an optical power that varies according to an azimuth angle. The observation device according to claim 1, wherein the second surface is positioned immediately before the eyeball. An observation apparatus according to claim 1, wherein the condition | α | ≤20 ° is satisfied, wherein α is the angle of the Zenyi perpendicular to the normal to the apex of the second face and to the optical axis of the eye. The observation apparatus according to claim 1, wherein the observation optical system is spectacle type having a thickness in the range of 10 mm to 15 mm. The observation device according to claim 1, wherein the third surface is an incident surface of light of an outer background. The observation apparatus according to claim 1, wherein the external brightness is detected to illuminate the original image such that natural light and backlight light are selectively used.