Source: https://patents.google.com/patent/USRE37667?oq=%22peter+l+basel%22+%22lsi+logic%22
Timestamp: 2018-05-25 13:37:01
Document Index: 797118143

Matched Legal Cases: ['art 1', 'art 1', 'art 1', 'art 1', 'art 2', 'art 2', 'art 2', 'art 2', 'art 3', 'art 3', 'art 3', 'art 3', 'arts 1']

USRE37667E1 - Head-mounted image display apparatus - Google Patents
USRE37667E1
USRE37667E1 US09481716 US48171600A USRE37667E US RE37667 E1 USRE37667 E1 US RE37667E1 US 09481716 US09481716 US 09481716 US 48171600 A US48171600 A US 48171600A US RE37667 E USRE37667 E US RE37667E
US09481716
An image display apparatus designed so that the field angle for observation can be widened without causing the substrate of an image display device to interfere with the observer's head and without increasing the overall size of the apparatus. The apparatus includes a two-dimensional image display device (6), an optical path splitting device (4), and a concave ocular mirror (5). The image display device (6) is used as an object point of the concave ocular mirror (5), and the object point is projected in the air as an enlarged image for an observer (1) without effecting image formation in the optical path. In the image display apparatus, either or both the optical path splitting device (4) and the concave ocular mirror (5) are decentered so that the display center (7) of the two-dimensional image display device (6) can be shifted away from the observer's head with respect to a reference axis (8) which perpendicularly intersects the observer's visual axis (3) lying when he or she sees forward.
This is a division of application Ser. No. 08/202,465, filed Feb. 28, 1994 now U.S. Pat. No. 5,539,578.
The present invention relates to an image display apparatus and, more particularly, to a portable head-mounted image display apparatus which can be retained on the user's head or face.
Helmet- and goggle-type head-mounted image display apparatuses, which are designed to be retained on the user's head or face, have heretofore been developed for the purpose of enabling the user to enjoy virtual reality or a wide-screen image by oneself.
The problem of the conventional head-mounted image display apparatus will be explained below more specifically. The two-dimensional image display device 6 needs to raise the pixel density in the display screen thereof and to thereby increase the number of pixels per unit area in order to realize high-definition display. Therefore, it is necessary to achieve electrical connection by leading electric wirings for switching of the pixels to the outside of the display screen. When the number of pixels is 100,000, for example, the number of electrical connections required is 300. Therefore, the conventional practice is to fabricate, a switching circuit at the periphery of the display screen to thereby reduce the number of electrical connections, i.e., to ten-odd connections. For the above-described reason, the substrate of the two-dimensional display device needs an area for electrical connection of the pixels with switching elements in addition to the area for display and requires a substrate larger in size than the display screen.
In view of the above-described problems of the background art, it is an object of the present invention to provide a head-mounted image display apparatus which is designed so that the field angle for observation can be widened without causing the substrate of a two-dimensional image display device to interfere with the observer's head and without increasing the overall size of the apparatus.
To attain the above-described object, the present invention first provides an image display apparatus including an image display device having a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis passing through the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path. In the image display apparatus, a straight line that connects an eye point and a position where the optical axis reflected by the magnifying reflecting mirror is reflected by the semitransparent reflecting surface is defined as a visual axis, and the semitransparent reflecting surface is disposed at a tilt to the image axis to change the angle of inclination of the semitransparent reflecting surface to the image axis so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
Secondly, the present invention provides an image display apparatus including an image display device having a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis passing through the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path. In the image display apparatus, a straight line that connects an eye point and a position where the optical axis reflected by the magnifying reflecting mirror is reflected by the semitransparent reflecting surface is defined as a visual axis, and the magnifying reflecting mirror is disposed at a tilt to the image axis so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
Thirdly, the present invention provides an image display apparatus including an image display device having a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis passing through the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path. In the image display apparatus, a straight line that connects an eye point and a position where the optical axis reflected by the magnifying reflecting mirror is reflected by the semitransparent reflecting surface is defined as a visual axis, and the magnifying reflecting mirror is shifted with respect to the image axis so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
Fourthly, the present invention provides an image display apparatus including an image display device having a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis reflected by the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path. In the image display apparatus, the semitransparent reflecting surface is a partially transmitting-reflecting surface composed of transmitting and reflecting regions which are locally distinguished from each other, and a straight line that connects an eye point and a position where the optical axis reflected by the magnifying reflecting mirror is transmitted by the partially transmitting-reflecting surface is defined as a visual axis. The partially transmitting-reflecting surface is disposed at a tilt to the image axis to change the angle of inclination of the partially transmitting-reflecting surface to the image axis so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
Fifthly, the present invention provides an image display apparatus including an image display device having a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis reflected by the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path. In the image display apparatus, the magnifying reflecting mirror is a partially transmitting-reflecting surface composed of transmitting and reflecting regions which are locally distinguished from each other, and a straight line that connects an eye point and a position where the optical axis reflected by the partially transmitting-reflecting surface is transmitted by the semitransparent reflecting surface is defined as a visual axis. The partially transmitting-reflecting surface is disposed at a tilt to the image axis so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
Sixthly, the present invention provides an image display apparatus including an image display device having a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis reflected by the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path. In the image display apparatus, a straight line that connects an eye point and a position where the optical axis reflected by the magnifying reflecting mirror is transmitted by the semitransparent reflecting surface is defined as a visual axis, and the magnifying reflecting mirror is shifted with respect to the image axis so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
Seventhly, the present invention provides a face-mounted image display apparatus including a face-mounted unit which has an image display device with a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis leaving the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path, and a support member for retaining the face-mounted unit on the observer's head. In the image display apparatus, a straight line that connects an eye point and a position where the optical axis reflected by the magnifying reflecting mirror is tangent to the semitransparent reflecting surface is defined as a visual axis, and at least the semitransparent reflecting surface or the magnifying reflecting mirror is decentered so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
π/4−ω/2≦θ<π/4
π/4−φ/2≦θ<π/4
where ω′=sin−1 (sinφ/n), ω is a half of the vertical field angle, and n is the refractive index of a medium constituting the prism.
In the fourth and fifth image display apparatuses, the partially transmitting-reflecting surface may be a surface formed by partially coating aluminum on a surface of an optical member having a refractive index (n) larger than 1 (n>1).
Ninthly, the present invention provides an image display apparatus including an image display device having a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis reflected by the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path. In the image display apparatus, the semitransparent reflecting surface is formed from a semitransparent film coated on a surface of an optical member having a refractive index (n) larger than 1 (n>1), and a straight line that connects an eye point and a position where the optical axis reflected by the magnifying reflecting mirror is transmitted by the semitransparent reflecting surface is defined as a visual axis. The semitransparent reflecting surface is disposed at a tilt to the image axis to change the angle of inclination of the semitransparent reflecting surface to the image axis so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
Tenthly, the present invention provides an image display apparatus including an image display device having a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis reflected by the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path. In the image display apparatus, the magnifying reflecting mirror is a magnifying reflecting surface formed from a semitransparent film coated on a surface of an optical member having a refractive index (n) larger than 1 (n>1), and a straight line that connects an eye point and a position where the optical axis reflected by the magnifying reflecting surface is transmitted by the semitransparent reflecting surface is defined as a visual axis. The magnifying reflecting surface is disposed at a tilt to the image axis so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
Eleventhly, the present invention provides an image display apparatus including an image display device having a screen for displaying an image, a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from the display screen, the optical axis being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis reflected by the semitransparent reflecting surface goes to and returns from the magnifying reflecting mirror to form a turn-back optical path. In the image display apparatus, the magnifying reflecting mirror is a totally reflecting mirror, and a straight line that connects an eye point and a position where the optical axis reflected by the totally reflecting mirror is transmitted by the semitransparent reflecting surface is defined as a visual axis. The totally reflecting mirror is disposed at a tilt to the image axis so that the angle (φ) made by intersection of the image axis extending from the image display device and the visual axis extending from the eye point is larger than 90° (φ>90°).
FIG. 1 is a sectional view showing a head-mounted image display apparatus according to Example 1 of the present invention.
FIG. 15(a), (b) and (c) are views for explanation of specific forms of a beam splitter surface of a prism beam splitter or a half-mirror.
Some examples of the head-mounted image display apparatus according to the present invention will be described below with reference to the accompanying drawings.
In this example, when an optical axis which is determined by a bundle of rays emitted from the screen of the two-dimensional image display device 6 is defined as an image axis x, the image axis x coincides with an optical axis 11 of the concave ocular mirror 5 which passes through the display center 7 of the two-dimensional image display device 6. The optical axis 11 is shifted through about 10° from a reference axis 8 which perpendicularly intersects the visual axis 3 and which passes through the point of intersection of the beam splitter surface 4 and the visual axis 3 so that the angle made by intersection of the image axis x and the visual axis 3 is larger than 90°, thereby ensuring the spacing between the observer 1 and the two-dimensional image display device 6. The shift angle Θ will hereinafter be referred to as “tilt angle 10” and defined as the angle made between the optical axis 11 of the concave ocular mirror 5 and the reference axis 8. It should be noted that in FIG. 1 the amount of shift of the display center 7 of the two-dimensional image display device 6 from the reference axis 8 is denoted by reference numeral 9. Thus, since both the two-dimensional image display device 6 and the concave ocular mirror 5 are tilted in comparison to those in the prior art, the angle 12 of inclination of the beam splitter surface 4 with respect to the visual axis 3 is larger than 45°, which is the original angle of inclination. That is, the beam splitter surface 4 is tilted, and the angle 12 becomes 45°+Θ/2.
In this example, it is important that the tilt angle Θ should be selected in the range of 0°<Θ<30°. If the tilt angle Θ is not larger than the lower limit of the above range, i.e., 0°, the two-dimensional image display device 6 cannot be disposed sufficiently away from the observer's head. If the tilt angle Θ is not smaller than the upper limit of the above range, i.e., 30°, the concave ocular mirror 5 comes closer to the observer.'s head (check) and may interfere with it.
In this example, the angle 12 of inclination of the half-mirror reflecting surface 4 is 45°−Θ/2. It is important that the tilt angle Θ should be selected in the range of 0°<Θ<30°. If the tilt angle Θ is not smaller than the upper limit of the above range, i.e., 30°, the amount of shift 9 of the display center 7 becomes 0. Consequently, the two-dimensional image display device 6 cannot effectively be separated away from the observer's head. If the tilt angle Θ is not larger than the lower limit of the above range, the bundle of rays from the two-dimensional image display device 6 is incident on the concave ocular mirror 5 at an excessively large angle to the optical axis 11 of the concave ocular mirror 5, causing large comatic aberration to be produced. Thus, it becomes impossible to obtain a wide field angle and high resolution.
Next, Example 3 of the present invention will be explained with reference to FIG. 3. This example is basically the same as Example 1. In this example, however, the optical axis 11 of the concave ocular mirror 5 is tilted with respect to the image axis x. In addition, a beam splitter prism P is used as an optical path splitting device, and a reverse reflecting mirror M is used as a concave ocular mirror 5. In this example, the beam splitter surface 4 is inclined at an angle of 45°, as denoted by reference numeral 12, and need not be further inclined in particular. It is important that the tilt angle Θ of the optical axis 11 of the concave ocular mirror 5 with respect to the reference axis 8 should be selected in the range of 0°<Θ<30°. If the tilt angle Θ is not smaller than the upper limit of the above range, i.e., 30°, the bundle of rays from the two-dimensional image display device 6 is incident on the concave ocular mirror 5 at an excessively large angle to the optical axis 11 of the concave ocular mirror 5, causing large comatic aberration to be produced by the concave ocular mirror 5. Accordingly, it becomes impossible to obtain a wide field angle and high resolution. If the tilt angle Θ is not larger than the lower limit of the above range, the amount of shift 9 of the display center 7 becomes 0. Consequently, the two-dimensional image display device 6 cannot effectively be separated away from the observer's head.
Next, Example 4 of the present invention will be explained with reference to FIG. 4. This example is basically the same as Example 2. The feature of this example resides in that the concave ocular mirror 5 is not tilted with respect to the axial ray on the visual axis 3 but disposed so that the optical axis thereof is parallel to the reference axis 8. In this case, if the tilt angle Θ is defined as the angle made between the optical axis 11 of the concave ocular mirror 5 and the axial ray reflected by the concave ocular mirror 5, the condition therefor is the same as in Example 2. In this example, the angle 12 of inclination of the beam splitter surface 4 with respect to the visual axis 3 is 45°−Θ/2.
The foregoing discussion centers about the tilt angle Θ from the reference axis 8, which perpendicularly intersects the visual axis 3 and which passes through the point of intersection of the beam splitter surface 4 and the visual axis 3. The following is another discussion which centers about the angle θ made between the image axis x of the two-dimensional image display device 6 [hereinafter referred to as “LCD (Liquid Crystal Display)] and the line normal to the half-mirror 4.
FIG. 5 shows a basic form of the image display apparatus according to the present invention which includes an LCD 6 for displaying an image, a half-mirror 4 which is obliquely disposed at the point of intersection of the optical axis (image axis) of the LCD 6 and the observer's visual axis for leading a bundle of rays from an image formed by the LCD 6 to an observer's eyeball (eye point) 2, and a magnifying reflecting mirror 5 of positive power which is disposed to face the LCD 6 across the half-mirror 4. The half-mirror 4 is disposed so that the angle e made between the line normal to the half-mirror 4 and the optical axis of the LCD 6 is smaller than π/4.
When the optical element b having refractive power is a single concave mirror, the distance l1 between the LCD a and the concave mirror b and the distance l2 between the concave mirror b and the eye point b are uniquely determined. Factors that have a degree of freedom in the arrangement of the optical system are the distance l21 between the concave mirror b and the half-mirror c and the angle made between the optical axis of the LCD a and the line normal to the half-mirror c. In the present invention, the following problems {circle around (1)} to {circle around (2)} can be solved by optimization of the angle of the half-mirror c:
{circle around (1)} As the size of the projection optical system increases, the load that is imposed on the user when wearing the image display apparatus on his/her head or face increases.
{circle around (2)} The diopter of the image for observation can be adjusted by moving the LCD along the optical axis. However, when the distance between the projection optical system and the LCD shortens, the half-mirror or the prism beam splitter may interfere with the LCD when the LCD is moved toward the magnifying reflecting mirror. Therefore, the diopter adjustable range narrows.
{circle around (3)} When the distance (working distance WD) between the projection optical system and the observer's eyeball shortens, it becomes impossible for the observer to view with his/her spectacles on, and each time users change from one to another, the diopter must be adjusted to a considerable extent. Further, when WD is short, there may be an interference between the projection optical system and the LCD on the one hand and the observer's face on the other.
WD=l2−(ef+fs) (1)
g(θ)=ef+fs (2)
It is assumed that the distance between the points p and q is 2k, and the point of intersection of the optical axis x of the LCD and a mutual line perpendicular to the optical axis x from the points p and q is e′.
When the curvature of the concave mirror b and the point p are fixed, the distance between the points e and e′ is a constant. Assuming that the distance is t, g(θ) is given by
g(θ)=k(tan θ+1/sin 2θ+tan θ cos 2θ−cos 2θ/tan 2θ)+t (3)
FIG. 9 is a graph showing the relationship between g(θ) and θ. When θ=π/4 (45°), g(θ) reaches a maximum. When θ>π4, g(θ) monotonously increases, whereas, when θ>π/4, g(θ) monotonously decreases. However, when π>π/4, the LCD a comes closer to the observer's face, which is undesirable.
π/4−φ′/2≦θ<π/4 (4)
ω′=sin−1 (sin φ/n) (5)
π/4−ω/2≦θ<π/4 (6)
Referring to FIG. 10, (a) is a sectional view of an optical system of Example 5 according to the present invention, and (b) is a sectional view of an optical system of prior art 1 corresponding to Example 5. In the figure, reference symbol E denotes the position of an observer's pupil, 6 an LCD, 4 a half-mirror, and 5 a concave mirror. The angle made between the optical axis of the LCD 6 and the line normal to the half-mirror 4 is 38.5° in Example 5; it is 45° in prior art 1. Numerical data in Example 5 and prior art 1 will be described later. Example 5 and prior art 1 are equal to each other in terms of the field angle, which is 35×26°, the size of the LCD 6, which is 26.0×19.1 mm, the distance from the LCD 6 to the concave mirror 5, and the distance from the concave mirror 5 to the pupil position E.
In this example, since the angle made between the optical axis of the LCD 6 and the line normal to the half-mirror 4 is set at 38.5°, the distance from the end surface of the optical system to the observer's eyeball can be increased to 17.5 mm from 16.5 mm in the prior art, and the distance from the end surface of the half-mirror 4 to the LCD 6 can be increased to 19 mm from 14 mm in the prior art. In addition, the area of the half-mirror 4 can be reduced by 7.5% in comparison to the prior art.
Referring to FIG. 11, (a) is a sectional view of an optical system of Example 6 according to the present invention, and (b) is a sectional view of an optical system of prior art 2 corresponding to Example 6. In the figure, reference symbol E denotes the position of an observer's pupil, 6 an LCD, 13 a prism beam splitter, 4 a half-mirror surface of the prism beam splitter 13, 5 a concave mirror, 14 a surface of the prism beam splitter 13 which faces the LCD 6, and 15 a surface of the prism beam splitter 13 which faces the observer's eyeball. The angle made between the optical axis of the LCD 6 and the line normal to the half-mirror 4 is 40.5° in Example 6; it is 45° in prior art 2. Numerical data in Example 6 and prior art 2 will be described later. Example 6 and prior art 2 are equal to each other in terms of the field angle, which is 37×27.6°, and the size of the LCD 6, which is 26.0×19.1 mm.
In this example, since a prism beam splitter is used as a half-mirror, divergence of the bundle of rays can be minimized, and the field angle can be widened. Further, since the angle made between the optical axis of the LCD 6 and the line normal to the half-mirror 4 is set at 40.5°, the distance from the prism end surface 15 to the observer's eyeball can be increased to 19.2 mm from 19.0 mm in the prior art, and the distance from the prism end surface 14 to the LCD 6 can be increased to 24.9 mm from 22.5 mm in the prior art. In addition, the volume of the prism can be reduced by 12% in comparison to the prior art.
Referring to FIG. 12, (a) is a sectional view of an optical system of Example 7 according to the present invention, and (b) is a sectional view of an optical system of prior art 3 corresponding to Example 7. In the figure, reference symbol E denotes the position of an observer's pupil, 6 an LCD, 13 a prism beam splitter, 4 a half-mirror surface of the prism beam splitter 13, 5 a concave mirror, 14 a surface of the prism beam splitter 13 which faces the LCD 6, 15 a surface of the prism beam splitter 13 which face the observer's eyeball, 16 a concave lens, and 17 a concave lens. The angle made between the optical axis of the LCD 6 and the line normal to the half-mirror 4 is 41° in Example 7; it is 45° in prior art 3. Numerical data in Example 7 and prior art 3 will be described later. Example 7 and prior art 3 are equal to each other in terms of the field angle, which is 44×33.2° , and the size of the LCD 6, which is 26.0×19.1 mm.
In Example 6, divergence of the bundle of rays in the prism is minimized by imparting positive power to the eyeball-side surface 15 of the prism in this example, thereby further widening the field angle. In the prior art, the distance from the LCD 6 to the prism is short, so that the diopter adjustable range is narrow when diopter correction is made in the negative direction (the image position is moved toward the near side) by moving the LCD 6. In this example, however, since the angle made between the optical axis of the LCD 6 and the line normal to the half-mirror surface 4 is set at 41°, the distance from the vertex of the prism end surface 14 to the line LCD 6 can be increased to 7.00 mm from 5.55 mm in the prior art. Thus, the diopter adjustable range can be enlarged by 1.3/m to the negative side in comparison to the prior art. Further, the distance from the prism end surface 15 to the observer's eyeball can be increased to 20.0 mm from 19.3 mm in the prior art. In addition, the volume of the prism can be reduced by 10% in comparison to the prior art.
Numerical data in the above-described Examples 5 to 7 and prior arts 1 to 3, which are obtained by backward tracing, will be shown below. These pieces of data are all shown in the order of backward tracing from the pupil E to the image display device 6. In all Examples, r0 denotes the pupil e, do is the working distance (WD), r1, r2 . . . are the radii of curvature of lens surfaces or reflecting surfaces, d1, d2 . . . are the spacings between adjacent lens surfaces, nd1, nd2. . . are the refractive indices for the spectral d-line of the glass materials, vd1, vd2 . . . are the Abbe's numbers of the glass materials, and r20 is the image display device 6. Further, the aspherical configuration is expressed by
z=ch2/{1+[1−c2(K+1)h2]1/2}+Ah4+Bh6+Ch8+Dh10 (7)
r0 = ∞ (E) d0 = 35.300000
r2 = ∞ (4) d1 = −14.172190
(θ = 38.500000°)
r2 = 85.48059 (5) d2 = 43.835912
r20 = ∞ (6)
r0 = ∞ (E) d0 = 32.000000
r2 = ∞ (4) d1 = −17.472190
(θ = 45.000000°)
r0 = ∞ (E) d0 = 19.200000
r1 = ∞ (15) d1 = 16.200000 nd1 = 1.516330 νd1 = 64.1
r2 = ∞ (4) d2 = −13.339170 nd2 = 1.516330 νd2 = 64.1
(θ = 40.500000°)
r3 = 123.40676 (5) d3 = 24.500000 nd3 = 1.516330 νd3 = 64.1
r4 = ∞ (14) d4 = 24.846988
r0 = ∞ (E) d0 = 19.000000
r1 = ∞ (15) d1 = 14.500000 nd1 = 1.516330 νd1 = 64.1
r2 = ∞ (4) d2 = −15.339170 nd2 = 1.516330 νd2 = 64.1
r3 = 123.40638 (5) d3 = 28.000000 nd3 = 1.516330 νd3 = 64.1
r4 = ∞ (14) d4 = 22.542094
r0 = ∞ (E) d0 = 20.000000
r1 = 79.40268 (15) d1 = 17.000000 nd1 = 1.516330 νd1 = 64.1
r2 = ∞ (4) d2 = −15.000000 nd2 = 1.516330 νd2 = 64.1
(θ = 41.500000°)
r3 = 55.04852 d2 = −0.500000
r4 = 140.20084 (16) d2 = −1.500000 nd3 = 1.805177 νd3 = 25.4
r5 = 9305.57882 (17) d2 = −2.600000 nd4 = 1.516330 νd4 = 64.1
r6 = 144.37844 (5) d3 = 2.600000 nd5 = 1.516330 νd5 = 64.1
r7 = 9305.57882 d2 = 1.500000 nd6 = 1.805177 νd6 = 25.4
r8 = 140.20084 d2 = 0.500000
r9 = 55.04852 d3 = 26.000000 nd7 = 1.516330 νd7 = 64.1
r10 = ∞ (14) d4 = 7.000000
spheric)
k=−1.000000
A=0.187498×10−4
r0 = ∞ (E) d0 = 19.340000
r1 = 91.35114 (15) d1 = 16.000000 nd1 = 1.516330 νd1 = 64.1
r2 = ∞ (4) d2 = −17.000000 nd2 = 1.516330 νd2 = 64.1
r3 = 50.81031 d2 = −0.500000
r4 = 140.90134 (16) d2 = −1.500000 nd3 = 1.805177 νd3 = 25.4
r6 = 151.92998 (5) d3 = 2.600000 nd5 = 1.516330 νd5 = 64.1
r8 = 140.90134 d2 = 0.500000
r9 = 50.81031 d3 = 29.000000 nd7 = 1.516330 νd7 = 64.1
r10 = ∞ (14) d4 = 5.550034
A=0.252379×10−4
Incidentally, no mention has been made of the form of the beam splitter surface 4 of the prism beam splitter or the half-mirror surface 4 in the foregoing description. In the present invention, it is possible to use any of a partially transmitting-reflecting surface 41, a semitransparent film 42 and a polarizing semitransparent film 43, which may be provided on a cemented surface of a prism or on a transparent substrate, for example, as shown at (a) to (c) in FIG. 15. More specifically, the beam splitter surface or half-mirror surface 4 is a surface that transmits about 50% of the quantity of incident light and reflects about 50% of it. The beam splitter surface or half-mirror surface 4 may be used with the transmittance-to-reflectance ratio varied in the range from 1:9 to 9:1, in addition to the above. The beam splitter surface or half-mirror surface 4 may be realized by any of the following methods: one in which the quantity of incident light is divided in terms of area; another in which the quantity of incident light is divided in terms of light intensity; and another in which the quantity of incident light is divided in terms of both area and intensity. In the case of the partially transmitting-reflecting surface 41 shown at (a) in FIG. 15, the quantity of incident light is divided in terms of area. In this case, reflection coating of aluminum or the like is provided on a cemented surface of a prism or on a transparent substrate (the refractive index n of which is larger than 1, i.e., n>1) at intervals, for example, in a lattice-like pattern of about several μm to 0.1 mm, whereby a reflectance and a transmittance are set overall (macrocosmically) by the ratio of the area of the reflecting portions of the area of the transmitting portions. In the case of the semitransparent film 42 shown at (b) in FIG. 15, a cemented surface of a prism or a transparent substrate (the refractive index n of which is larger than 1, i.e. n>1) is coated with a metallic, extremely thin film, e.g., an extremely thin film of aluminum or chromium, or a dielectric multilayer film of SiO2, MgF2, etc., thereby dividing the quantity of incident light. The polarizing semitransparent film 43 shown at (c) in FIG. 15 divides the quantity of incident light by separating polarized light components of the incident light. More specifically, the polarizing semitransparent film 43 is coated on a cemented surface of a prism or on a transparent substrate to allow p-and s-polarized light components to be selectively transmitted or reflected to thereby divide the quantity of the incident light.
1. An image display apparatus including:
an image display device having a screen for displaying an image,
a semitransparent reflecting surface disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from said display screen, said optical axis is being defined as an image axis, and
a magnifying reflecting mirror disposed so that an optical axis reflected by said semitransparent reflecting surface goes to and returns from said magnifying reflecting mirror to form a turn-back optical path,
wherein the improvement is characterized in that:
said semitransparent reflecting surface is a surface having both reflecting and transmitting functions composed of transmitting and reflecting regions which are locally distinguished from each other;
a straight line that connects an eye point and a position where the optical axis reflected by said magnifying reflecting mirror is transmitted by said surface having both reflecting and transmitting functions is defined as a visual axis; and
said surface having both reflecting and transmitting functions is disposed at a tilt to said image axis to change the angle of inclination of said surface having both reflecting and transmitting functions to said image axis so that an angle (φ) made by intersection of said image axis extending from said image display device and said visual axis is extending from said eye point is larger than 90° (φ>90°), a space between said surface having both reflecting and transmitting functions and said magnifying reflecting mirror being formed from a prism which is filled with a medium having a refractive index (n) larger than 1 (n>1).
2. An image display apparatus including:
a semitransparent reflecting surface which is a surface having both reflecting and transmitting functions disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from said display screen, said optical axis being defined as an image axis, and
a magnifying reflecting mirror disposed so that an optical axis reflected by said semitransparent reflecting surface goes to and returns from said magnifying reflecting mirror to form a turn-back optical path
said magnifying reflecting mirror is a partially transmitting-reflecting surface composed of transmitting and reflecting regions which are locally distinguished from each other;
a straight light that connects an eye point and a position where the optical axis reflected by said partially transmitting-reflecting surface is transmitted by said semitransparent reflecting surface is defined as a visual axis; and
said partially transmitting-reflecting surface is disposed at a tilt to said image axis so that an angle (φ) made by intersection of said image axis extending from said image display device and said visual axis extending from said eye point is larger than 90° (φ>90°), a space between said semitransparent reflecting surface and said magnifying reflecting mirror being formed from a prism which is filled with a medium having a refractive index (n) larger than 1 (n>1).
3. A face-mounted image display apparatus including
a face-mounted unit having an image display device with a screen for displaying an image, a semitransparent reflecting surface which is a surface having both reflecting and transmitting functions disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from said display screen, said optical axis is being defined as an image axis, and a magnifying reflecting mirror disposed to that an optical axis leaving said semitransparent reflecting surface goes to and returns from said magnifying reflecting mirror to form a turn-back optical path, and
a straight line that connects an eye point and a position where the optical axis reflected by said magnifying reflecting mirror is tangent to said semitransparent reflecting surface is defined as a visual axis; and
at least one of said semitransparent reflecting surface and said magnifying reflecting mirror is decentered so that an angle (φ) made by intersection of said image axis extending from said image display device and said visual axis extending from said eye point is larger than 90° (φ>90°), a space between said semitransparent reflecting surface and said magnifying reflecting mirror being formed from a prism which is filled with a medium having a refractive index (n) larger than 1 (n>1).
4. An image display apparatus according to claim 1, 2, or 3, wherein said semitransparent reflecting surface is formed from a half-mirror.
5. An image display apparatus according to claim 1, 2, or 3, wherein said semitransparent reflecting surface is formed from a prism.
6. An image display apparatus according to claim 1, 2, or 3, wherein an angle made between a line normal to said semitransparent reflecting surface and said image axis is smaller than π/4.
7. An image display apparatus according to claim 6, wherein said semitransparent reflecting surface is formed from a half-mirror, and an angle θ between a line normal to said half-mirror and said image axis satisfies the following condition:
where φ is a half of a vertical field angle.
8. An image display apparatus according to claim 6, wherein said semitransparent reflecting surface is formed from a prism beam splitter having a half-mirror surface, and an angle θ between a line normal to said half-mirror surface and said image axis satisfies the following condition:
π/4−φ′/2≦θ<π/4
where φ′=sin−1 (sinφ/n), φ is a half of a vertical field angle, and n is the refractive index of a medium constituting said prism.
9. An image display apparatus according to claim 1 or 2, wherein said partially transmitting-reflecting surface is a surface formed by partially coating aluminum on a surface of an optical member having a refractive index (n) larger than 1 (n>1).
10. A head-mounting image display apparatus having an image display device, a semitransparent reflecting mirror, which is a surface having both reflecting and transmitting functions and a magnifying reflecting mirror, in which said image display device is used as an object point of said magnifying reflecting mirror, and the object point is projected in the air as an enlarged image for an observer without effecting image formation in an optical path,
at least one of said semitransparent reflecting mirror and said magnifying reflecting mirror are decentered so that a display center of said image display device is selectively shiftable away from the observer's head with respect to a reference axis which perpendicularly intersects an observer's visual axis laying when he or she sees forward, a space between said semitransparent reflecting surface and said magnifying reflecting mirror being formed from a prism which is filled with a medium having a refractive index (n) larger than 1 (n>1).
11. An image display apparatus including:
a surface having both reflecting and transmitting functions disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from said display screen, said optical axis is being defined as an image axis, and
a magnifying reflecting mirror disposed so that an optical axis reflected by said surface having both reflecting and transmitting functions goes to and returns from said magnifying reflecting mirror to form a turn-back optical path,
said surface having both reflecting and transmitting functions is disposed at a tilt to said image axis to change the angle of inclination of said surface having both reflecting and transmitting functions to said image axis so that an angle (φ) made by intersection of said image axis extending from said image display device and said visual axis is extending from said eye point is larger than 90 ° (φ> 90 °), a space between said surface having both reflecting and transmitting functions and said magnifying reflecting mirror being formed from a prism which is filled with a medium having a refractive index (n) larger than 1 (n>1 ).
a surface having both reflecting and transmitting functions disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from said display screen, said optical axis being defined as an image axis, and
a magnifying reflecting mirror disposed so that an optical axis reflected by said surface having both reflecting and transmitting functions goes to and returns from said magnifying reflecting mirror to form a turn-back optical path, wherein:
a straight line that connects an eye point and a position where the optical axis reflected by said partially transmitting-reflecting surface is transmitted by said surface having both reflecting and transmitting functions is defined as a visual axis; and
said partially transmitting-reflecting surface is disposed at a tilt to said image axis so that an angle (φ) made by intersection of said image axis extending from said image display device and said visual axis extending from said eye point is larger than 90 ° (φ> 90 °), a space between said surface having both reflecting and transmitting functions and said magnifying reflecting mirror being formed from a prism which is filled with a medium having a refractive index (n) larger than 1 (n>1 ).
13. A face-mounted image display apparatus including a face-mounted unit having an image display device with a screen for displaying an image, a surface having both reflecting and transmitting functions disposed at an angle of inclination to an optical axis which is determined by a bundle of rays emitted from said display screen, said optical axis is being defined as an image axis, and a magnifying reflecting mirror disposed so that an optical axis leaving said surface having both reflecting and transmitting functions goes to and returns from said magnifying reflecting mirror to form a turn-back optical path, and
a straight line that connects an eye point and a position where the optical axis reflected by said magnifying reflecting mirror is tangent to said surface having both reflecting and transmitting functions is defined as a visual axis, and
at least one of said surface having both reflecting and transmitting functions and said magnifying reflecting mirror is decentered so that an angle (φ) made by intersection of said image axis extending from said image display device and said visual axis extending from said eye point is larger than 90 ° (φ> 90 °), a space between said surface having both reflecting and transmitting functions and said magnifying reflecting mirror being formed from a prism which is filled with a medium having a refractive index (n) larger than 1 (n>1 ).
14. An image display apparatus according to claim 11, 12, or 13, wherein said surface having both reflecting and transmitting functions is formed from a half-mirror.
15. An image display apparatus according to claim 11, 12, or 13, wherein said surface having both reflecting and transmitting functions is formed from a prism.
16. An image display apparatus according to claim 11, 12, or 13, wherein an angle made between a line normal to said surface having both reflecting and transmitting functions and said image axis is smaller than π/4.
17. An image display apparatus according to claim 16, wherein said surface having both reflecting and transmitting functions is formed from a half-mirror, and an angle θ between a line normal to said half-mirror and said image axis satisfies the following condition:
where φ is half of a vertical field angle.
18. An image display apparatus according to claim 16, wherein said surface having both reflecting and transmitting functions is formed from a prism beam splitter having a half-mirror surface, and an angle θ between a line normal to said half-mirror surface and said image axis satisfies the following condition:
where φ′=sin−1 (sinφ/n), φ is half of a vertical field angle, and n is the refractive index of a medium constituting said prism.
19. An image display apparatus according to claim 11 or 12, wherein said surface having both reflecting and transmitting functions is a surface formed by partially coating aluminum on a surface of an optical member having a refractive index (n) larger than 1 (n>1 ).
20. A head-mounted image display apparatus having an image display device, a surface having both reflecting and transmitting functions and a magnifying reflecting mirror, in which said image display device is used as an object point of said magnifying reflecting mirror, and the object point is projected in the air as an enlarged image for an observer without effecting image formation in an optical path, wherein:
at least one of said surface having both reflecting and transmitting functions and said magnifying reflecting mirror are decentered so that a display center of said image display device is selectively shiftable away from the observer's head with respect to a reference axis which perpendicularly intersects an observer's visual axis laying when he or she sees forward, a space between said surface having both reflecting and transmitting functions and said magnifying reflecting mirror being formed from a prism which is filled with a medium having a refractive index (n) larger than 1 (n>1 ).
21. An image display apparatus according to claim 11, 12, or 13, wherein said surface having both reflecting and transmitting functions is composed of transmitting and reflecting regions which are locally distinguished from each other.
22. An image display apparatus according to claim 11, 12, 13, or 20, wherein the bundle of rays emitted from said image display device is transmitted by at least said surface having both reflecting and transmitting functions and reflected by said magnifying reflecting mirror and further reflected by said surface having both reflecting and transmitting functions.
23. An image display apparatus according to claim 11, 12, 13, or 20, wherein the bundle of rays emitted from said image display device is reflected by at least said surface having both reflecting and transmitting functions and further reflected by said magnifying reflecting mirror and then transmitted by said surface having both reflecting and transmitting functions.
24. An image display apparatus according to claim 11, 12, 13, or 20, wherein said surface having both reflecting and transmitting functions is formed from a plane mirror.
US09481716 1993-03-02 2000-01-12 Head-mounted image display apparatus Expired - Lifetime USRE37667E1 (en)
JP4142193A JPH06258594A (en) 1993-03-02 1993-03-02 Head-mount type visual display device
JP5-41421 1993-03-02
JP5-286647 1993-11-16
JP28664793A JP3397256B2 (en) 1993-11-16 1993-11-16 The video display device
US08202465 US5539578A (en) 1993-03-02 1994-02-28 Image display apparatus
US08633499 US5708529A (en) 1993-03-02 1996-04-17 Head-mounted image display apparatus
US09481716 USRE37667E1 (en) 1993-03-02 2000-01-12 Head-mounted image display apparatus
US08633499 Reissue US5708529A (en) 1993-03-02 1996-04-17 Head-mounted image display apparatus
USRE37667E1 true USRE37667E1 (en) 2002-04-23
ID=26381035
US08202465 Expired - Lifetime US5539578A (en) 1993-03-02 1994-02-28 Image display apparatus
US08633499 Expired - Lifetime US5708529A (en) 1993-03-02 1996-04-17 Head-mounted image display apparatus
US09481716 Expired - Lifetime USRE37667E1 (en) 1993-03-02 2000-01-12 Head-mounted image display apparatus
US (3) US5539578A (en)
JPH07325266A (en) * 1994-06-01 1995-12-12 Olympus Optical Co Ltd Video display device
JP3594264B2 (en) * 1995-10-16 2004-11-24 オリンパス株式会社 Image display device
JPH09113842A (en) * 1995-10-17 1997-05-02 Olympus Optical Co Ltd Head or face mount type video display device
FR2755271B1 (en) * 1996-10-25 1998-12-18 Monot Benoist Method and optical and electronic system of image processing
JP3607787B2 (en) * 1997-02-14 2005-01-05 三菱電機株式会社 Camera and peripheral visual confirmation apparatus for a vehicle using the same
US6212020B1 (en) 1997-06-25 2001-04-03 Ect Eye Control Technique Ab Head-mounted carrier for positioning opto-electronic devices in front of the user's eyes
JP2002122783A (en) 2000-10-13 2002-04-26 Olympus Optical Co Ltd Observation optical system, image pickup optical system and device using those
JP4812181B2 (en) 2001-04-20 2011-11-09 オリンパス株式会社 An observation optical system and the imaging optical system and apparatus using the same
US20080062514A1 (en) * 2006-09-08 2008-03-13 Asia Optical Co., Inc. Digital telescopic sight
US8094377B2 (en) * 2009-05-13 2012-01-10 Nvis, Inc. Head-mounted optical apparatus using an OLED display
CN102253491B (en) * 2011-06-24 2014-04-02 南京炫视界光电科技有限公司 Virtual image display light machine with unequal focal lengths and high magnification
US9323059B2 (en) * 2012-12-21 2016-04-26 Industrial Technology Research Institute Virtual image display apparatus
FR3014567B1 (en) * 2013-12-11 2017-09-08 Thales Sa display system comprising a screen comprising a network of three-dimensional microstructures REFLECTIVE
WO2017003719A3 (en) * 2015-06-30 2017-02-23 3M Innovative Properties Company Illuminator
US4212526A (en) * 1978-08-22 1980-07-15 Minolta Camera Kabushiki Kaisha Viewfinder for single lens reflex camera
US5200856A (en) * 1991-02-12 1993-04-06 Intertechnique Helmet sight including a graticule image with increasing deviation with helmet displacement
JP3191389B2 (en) 1992-03-31 2001-07-23 ソニー株式会社 Recording method and a tracking error detecting apparatus of the tracking error detecting signal
US5539578A (en) 1996-07-23 grant
US5708529A (en) 1998-01-13 grant
US5745295A (en) 1998-04-28 Image display apparatus
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