JPH0746513A - Headphone type image display device - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a headphone type image display device capable of vertically moving the position of a reflecting mirror according to the characteristics and usage form of a wearer and capable of displaying a bright image screen. is there. In a headphone type image display device, a movable arm extends from the vicinity of an ear pad, and a concave reflection mirror (or an elliptical mirror or a parabolic mirror) whose focal position is near the pupil of the wearer's eye is provided at the arm tip. A relay optical system or an optical fiber array optical system is arranged between the small display device and the concave reflection mirror.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head-mounted headphone type video display device capable of simultaneously viewing video and audio.

[0002]

2. Description of the Related Art With the practical use of a small display device, various head-mounted image display devices using the small display device have been developed. Above all, the one-eye type image display device using one small display device has been attracting attention because of the feature that the image from the small display device and the image of the outside world can be viewed at the same time. As the form of the one-eye type image display device, as disclosed in, for example, Japanese Patent Laid-Open No. 62-214782, there is a form in which one small display device is attached to an eyeglass type frame, As disclosed in Kaihei 3-132180 and JP-A-4-23579,
A small display device is installed near the head, an arm-shaped support with a reflection mirror attached to the tip is arranged in the face direction from the head, and the image screen from the small display device is reflected by the reflection mirror to be viewed. The latter type is attracting attention because of its ease of use and wide visibility.

[0003]

However, in the conventional example provided with the above-mentioned arm-shaped support, the support is not movable (in the case of JP-A-4-23579) or movable. Since the reflecting mirror did not move in the vertical direction (in the case of Japanese Patent Laid-Open No. 3-132180), the video screen of the small display device could not be installed at the optimum position for the wearer (through the reflecting mirror). Further, depending on the usage pattern, it may be more convenient to install the video screen of the small display device slightly below (or slightly above) the line of sight. However, the conventional video display device is used according to such usage pattern. I couldn't. Of course, it is possible to simply move the reflection mirror and the like up and down with the same type of conventional image display device, but in that case, the optical correspondence between the wearer's eyes, the reflection mirror, and the small display device is possible. It is clear that the relationship is broken and the video screen from the small display device cannot be seen.

By the way, in a video display device in which a reflecting mirror is installed at the tip of the arm-shaped support and a small display device is installed near the head, the distance between the small display device and the wearer's eyes becomes long, so that a display is made. There was a problem that the displayed image screen became dark.

Therefore, the present invention solves the above problems, and its purpose is to maintain the optical correspondence between the wearer's eyes, the reflection mirror, and the small display device. , A headphone type image display device in which the position of the reflection mirror can be moved in the vertical direction according to the characteristics and usage pattern of the wearer, and it is bright even when a small display device is installed away from the wearer's eyes. An object is to provide a headphone type video display device capable of displaying a video screen.

[0006]

In order to solve the above problems, a headphone type image display device of the present invention is provided with a small display device in the vicinity of an ear pad on one side of a headphone with its image screen facing forward. Attaching a substantially L-shaped movable arm that can move up and down around the headphone portion to which the small display device is attached as a substantial rotation center, and display a video screen from the small display device on the eye of the wearer. A concave reflection mirror for reflecting light in a direction is attached to the tip of the movable arm, and in this case, the concave reflection mirror has a curved surface characteristic such that the focus position of the concave reflection mirror is near the pupil of the wearer's eye. Further, it is characterized in that the sound from the small display device can be heard through the headphones.

Further, in order to prevent the brightness of the video screen from decreasing, a small display device is attached near one of the ear pads of the headphones in such a state that the video screen faces forward, and the small display device is attached. The concave reflection mirror for reflecting the image screen from the small display device in the direction of the wearer's eyes is provided with a substantially L-shaped movable arm that can move up and down with the headphone part as a rotation center. Attached to the tip of the movable arm, in that case, the concave reflection mirror has a curved surface characteristic such that the focal position of the concave reflection mirror is near the pupil of the wearer's eye. A relay optical system is disposed between the mirrors, and the headphone is capable of listening to the sound from the small display device.

Further, as another method for preventing a decrease in the brightness of the video screen, a small display device is attached near the ear pad on one side of the headphone with the video screen facing forward, and the small display device is provided. An ellipse which is provided with a substantially L-shaped movable arm capable of moving in the vertical direction with the headphone part attached with as a center of rotation, and which reflects the video screen from the small display device in the direction of the wearer's eyes. A reflecting mirror is attached to the tip of the movable arm, and two groups of lens systems are arranged between the small display device and the elliptical reflecting mirror. In that case, the elliptical reflecting mirror and the two groups of lenses are relay optical systems. It is arranged so that
The first focus of the elliptical mirror is located near the center of the lens of the lenses of the second group, which is closer to the elliptical reflection mirror,
The second focal point has a curved surface characteristic that is located near the pupil of the wearer's eyes, and is further characterized in that the sound from the small display device can be heard through the headphones.

In addition, as another method for preventing a decrease in the brightness of the video screen, a small display device is attached near the ear pad on one side of the headphone with the video screen facing forward, and the small display is displayed. A substantially L-shaped movable arm that can move up and down with the headphone part to which the device is attached as a substantial rotation center is attached, and the video screen from the small display device is reflected in the direction of the wearer's eyes. A concave reflection mirror is attached to the tip of the movable arm, and in this case, the concave reflection mirror has curved surface characteristics such that the focal position of the concave reflection mirror is near the pupil of the wearer's eye. An optical fiber array optical system is arranged between the device and the concave reflection mirror, and the sound from the small display device can be heard through the headphones. It is characterized in.

Further, the concave reflection mirror is a parabolic mirror having a focal length such that the focal point is near the pupil of the eye of the wearer.

Further, the small display device is a liquid crystal display device.

[0012]

In the above structure, since the focal point formed by the reflecting mirror is located near the pupil of the wearer's eye,
The wearer can move the movable arm in the vertical direction to form a reflection image of the small display device at a position where he can easily see the image, and can see the video screen.

Further, a relay optical system or an optical fiber array is installed between the small display device and the reflection mirror, and by guiding the image screen of the small display device onto the reflection mirror, a bright image screen can be realized. .

[0014]

EXAMPLES The present invention will be described in detail below based on examples. However, in the following embodiments, a liquid crystal panel is used as the small display device, but other than the liquid crystal panel, for example, a CRT display, an EL panel, and an L display.
Any small and lightweight display device such as an ED panel can be similarly used. In the following embodiments, the same or similar components will be denoted by the same reference numerals.

(Embodiment 1) FIG. 1 is a plan view of a headphone type image display device according to an embodiment of the present invention when in use.
2 is a side view of the same.

In FIGS. 1 and 2, 101 is an ear pad incorporating a small speaker, 102 is a wearing band, and the band is connected to the ends of the two ear pads to form a headphone 103. The function of the headphones here is exactly the same as that of headphones that listen to general sounds. From the connecting portion of the ear pad on one side of this headphone and the wearing belt, the movable arm 105
Are arranged in the face direction of the wearer 104, and this arm has a structure capable of rotating and moving in the vertical direction with the substantially central axis 106 of the ear pad as the axis of rotation.

A liquid crystal panel unit 107 and a backlight unit 108 as a small display device are provided near the ear pad of the movable arm 105, a folding mirror 109 is provided in the middle of the arm, and a concave reflection is provided at the tip of the arm. A mirror 110 is arranged. This movable arm can be slightly rotated in the horizontal direction with the center of the folding mirror 109 as the axis 111, and along with the above vertical movement, the position of the concave reflection mirror 110 can be freely adjusted according to the wearer. It has a structure that allows it.

The liquid crystal panel unit and the small speaker are connected to an external signal source (not shown) by a transmission cable 112. An image screen formed by the liquid crystal panel has its optical path bent by a folding mirror, and is guided to the wearer's eyes 113 while being condensed by a concave reflection mirror. The trajectory 114 of the light ray from the liquid crystal panel to the eyes of the wearer is shown by a broken line in FIG. At this time, the image screen is enlarged and displayed by the condensing action of the concave reflection mirror. Therefore, the wearer sees a large image screen which is enlarged in front.

Next, the shape of the reflection surface of the concave reflection mirror will be described. The center of curvature of the reflection surface of the concave reflection mirror in the meridional direction is designed to be near the pupil of the wearer's eye. Therefore, even if the movable arm is moved in the vertical direction to some extent, the image screen is always incident on the vicinity of the pupil of the eye through the concave reflection mirror, so that the image screen is not lost.

Therefore, the position of the concave reflection mirror (that is, the position of the image screen) can be freely moved in the vertical direction according to the preference of the wearer, which is convenient for the wearer. At the same time, depending on the usage pattern, it may be more convenient to dispose the video screen slightly below (or slightly above) the horizontal line-of-sight direction 115. Since it can be dealt with by moving in the direction (or upward),
It is possible to further promote the diversification of applications.

Instead of the concave reflection mirror, a parabolic mirror (in this case, an off-axis parabolic mirror) having optical characteristics such that the focal point is near the pupil of the wearer's eye is used. It should be additionally noted that the same function as in the case of using the concave reflection mirror is exerted.

(Embodiment 2) In the headphone type image display device shown in the embodiment 1, it is expected that the image screen becomes dark because the distance from the small display device to the concave reflection mirror is relatively long. Therefore, an embodiment of a headphone type video display device in which the reduction in the brightness of the video screen is improved will be described.
FIG. 3 shows a plan view of the headphone type image display device according to this embodiment when it is used, and FIG. 6 shows an explanatory view of an optical system used therein. It should be noted that the converging action by the concave reflecting mirror can be regarded as equivalent to the converging action by the convex lens, although the emitting direction of the light beam is different. Therefore, in FIG. 6 to FIG. The optical path is shown ignoring the reflection effect of the light rays by the reflection mirror.

In the headphone type image display device according to the present embodiment, a relay optical system consisting of three lenses is arranged on the way from the small display device to the concave reflection mirror, and the image screen from the small display device is concavely reflected with high efficiency. It is characterized in that it leads to a mirror, and as a result, a bright image screen is obtained. Therefore, in the headphone type video display device of the present embodiment, the other mechanism except the optical system is the same as that of the headphone type video display device of the first embodiment.

As shown in FIG. 3, an incident side lens 301 is provided between the liquid crystal panel unit 107, which is a compact display device, and the folding mirror 109, and a relay lens 302 is emitted between the folding mirror 109 and the concave reflection mirror 110. The side lens 303 is arranged. At this time, the focal lengths of the incident side lens and the outgoing side lens are substantially equal to each other, and the focal length of the relay lens is approximately 1/2 of the focal lengths of the incident side lens and the outgoing side lens. Further, regarding the positional relationship of the three lenses, as shown in FIG. 6, the relay lens 302 is placed substantially in the middle of the entrance side lens 301 and the exit side lens 303, and at the same time, the entrance side lens and the exit side lens are relay lenses. It is placed at a distance of about twice the focal length of the relay lens from the center of. The folding mirror 109 is omitted in FIG.

The light 304 entering the incident side lens 301 from the liquid crystal panel unit 107 passes through substantially the central portion of the relay lens 302, and reaches the concave reflection mirror 110 via the emission side lens 303. At this time, since the light entering the incident side lens from the liquid crystal panel is not a perfect parallel light, there is also light 305 that passes around the periphery of the relay lens, but in that case, the refraction of the relay lens causes the relay lens to move. Since it reaches the concave reflection mirror through the exit position of the exit lens corresponding to the entrance position of the entrance lens as the center of symmetry, the optical loss hardly occurs.

Therefore, by arranging the relay optical system, the image screen of the liquid crystal panel reaches the concave reflection mirror while maintaining almost the same state without light loss, and is condensed by the concave reflection mirror and mounted. Even if the distance between the liquid crystal panel, which is a small-sized display device, and the concave reflection mirror is relatively long, it is guided to the eyes of a person, so that the rate of lowering the brightness of the image screen is small.

However, when passing through the relay optical system,
Since the display direction rotates by 180 degrees, it is necessary to set the display direction of the screen of the small display device in consideration of this point.

In place of the concave reflection mirror, a parabolic mirror (in this case, an off-axis parabolic mirror) having optical characteristics such that the focus position is near the pupil of the wearer's eye is used. It should be additionally noted that the same function as in the case of using the concave reflection mirror is exerted.

(Embodiment 3) Another embodiment of a headphone type image display device in which the relay optical system shown in Embodiment 2 is arranged will be described. FIG. 4 shows a plan view of the headphone type image display device according to this embodiment when it is used, and FIG. 7 shows an explanatory view of an optical system used therein.

The headphone type image display apparatus according to the present embodiment is characterized in that the concave reflection mirror is an elliptical reflection mirror, so that the emission side lens, which was required in the relay optical system of the second embodiment, is unnecessary. There is. Therefore, in the headphone type video display device of the present embodiment, the other mechanism except the optical system is the same as that of the headphone type video display device of the second embodiment.

As can be seen from FIGS. 4 and 7, only the relay lens 302 is arranged between the folding mirror 109 and the concave reflection mirror 110. In this case, the concave reflection mirror 110 is an elliptical mirror and is the first of the two focal points.
The focus 401 is set substantially at the center of the relay lens 302, and the second focus 402 is set near the pupil of the wearer's eye 113.

With the above arrangement, the first elliptical reflection mirror
Light passing through the center of the relay lens, which is the focal point, is
Since it reaches the vicinity of the pupil of the wearer's eye, which is the focal point, the same function as the relay optical system shown in the second embodiment can be achieved with only the three components of the incident side lens, the relay lens, and the elliptical reflection mirror.

Therefore, since the lens on the output side is unnecessary,
It can contribute to the downsizing and cost reduction of the headphone type image display device.

(Embodiment 4) Even in the case where the distance from the small display device shown in Embodiments 2 and 3 to the concave reflection mirror is relatively long, a headphone type image display device which does not cause a decrease in the brightness of the image screen is obtained. Another embodiment will be described. FIG. 5 is a plan view of the headphone type image display device according to this embodiment when it is used, and FIG. 8 is an explanatory view of an optical system used therein.

The headphone type image display device according to the present embodiment is characterized in that the optical fiber array optical system is arranged between the small display device and the concave reflection mirror. Therefore, in the headphone type image display device of the present embodiment,
The other mechanism except the optical system is the same as that of the headphone type image display device of the first embodiment.

As can be seen from FIGS. 5 and 8, the liquid crystal panel unit 107, which is a small display device, and the concave reflection mirror 1.
An entrance-side coupling lens 501, an optical fiber array 502, and an exit-side coupling lens 503 are arranged between the positions 10. The optical fiber array is an optical element in which a large number of optical fibers each having a diameter of several μm are arranged in an array and which can transmit a two-dimensional image. Since the pixel density of the optical fiber array (that is, the number density of the optical fibers forming the optical fiber array) is sufficiently higher than the pixel density of the liquid crystal panel, the diameter of the optical fiber array is generally smaller than the diagonal length of the liquid crystal panel. May be. Therefore, in an actual optical system, an entrance side coupling lens 501 and an exit side coupling lens 503 are arranged on both sides of the optical fiber array 502, and at the same time, both ends of the optical fiber array itself are processed into a lens shape to form two coupling lenses. It improves the coupling efficiency of.

With the above-mentioned structure, the image screen of the liquid crystal panel is reduced by the incident side coupling lens and guided to the optical fiber array, and after being transmitted through the optical fiber array, enlarged to the original size through the emission side coupling lens to form the concave reflection. Reach the mirror.

Therefore, by disposing the optical fiber array optical system, the image screen incident from the liquid crystal panel is
The light reaches the concave reflection mirror while maintaining almost the same state without light loss, and is condensed by the concave reflection mirror and guided to the wearer's eyes. Therefore, even when the distance between the liquid crystal panel, which is a small-sized display device, and the concave reflection mirror is relatively long, the rate of lowering the brightness of the video screen is small. In addition, since the optical fiber array is flexible, it can be used without any problem even if it is attached to a movable arm.

In place of the concave reflection mirror, a parabolic mirror (in this case, an off-axis parabolic mirror) having optical characteristics such that the focus position is near the pupil of the wearer's eye is used. It should be additionally noted that the same function as in the case of using the concave reflection mirror is exerted.

[0040]

As described above, in the headphone type image display device of the present invention, the focus position formed by the concave reflection mirror is located near the pupil of the wearer's eye, and extends from the vicinity of the ear pad of the headphone. Since the arm is movable, even if you move the movable arm up and down,
The optical image formation relationship between the compact display device, the concave reflection mirror, and the pupil of the wearer's eyes is not broken. Therefore, the wearer moves the movable arm in the vertical direction to reflect the compact display device at a position where the wearer can easily see it. An image (video screen) can be formed and the video screen can be viewed. Since such a mechanism can change the viewing position of the video screen according to the wearer's usage pattern and the wearer's own preference, it is not only convenient, but also has the excellent effect of reducing the feeling of fatigue during use. Have both.

Further, a relay optical system or an optical fiber array optical system is installed between the small display device and the concave reflection mirror,
By transmitting and displaying the video screen of the small display device through them, it is possible to realize a bright video screen even if the distance between the small display device and the eyes of the wearer becomes long.

[Brief description of drawings]

FIG. 1 is a plan view of the headphone type image display device according to the first embodiment of the present invention when in use.

FIG. 2 is a side view of the headphone type image display device according to the first embodiment of the present invention when in use.

FIG. 3 is a plan view of the headphone type image display device according to the second embodiment of the present invention when in use.

FIG. 4 is a plan view of the headphone type image display device according to the third embodiment of the present invention when in use.

FIG. 5 is a plan view of the headphone type image display device according to the fourth embodiment of the present invention when in use.

FIG. 6 is an explanatory diagram of an optical system of the headphone type image display device of the present invention shown in the second embodiment.

FIG. 7 is an explanatory diagram of an optical system of the headphone type image display device of the present invention shown in the third embodiment.

FIG. 8 is an explanatory diagram of an optical system of the headphone type image display device of the present invention shown in Example 4.

[Explanation of symbols]

 101 Ear Pad 102 Wearing Belt 103 Headphones 104 Wearer 105 Movable Arm 106 Approximate Center Axis 107 Liquid Crystal Panel Unit 108 Backlight Unit 109 Folding Mirror 110 Concave Reflecting Mirror 111 Center of Folding Mirror 112 Transmission Cable 113 Eyes (or Eyes) 114 Ray Trajectory 115 Horizontal Line of Sight 301 Incident Side Lens 302 Relay Lens 303 Emitting Side Lens 304 Light that passes through the central part of the relay lens 305 Light that passes through the peripheral part of the relay lens 401 First Focus 402 Second Focus 501 Incident Side Coupling Lens 502 Optical fiber array 503 Outgoing side coupling lens

Claims (6)

[Claims] 1. A small display device is attached in the vicinity of an ear pad on one side of a headphone with the image screen thereof facing forward, and the headphone part to which the small display device is attached is moved about in the vertical direction. Is attached to the tip of the movable arm, which is provided with a substantially L-shaped movable arm for reflecting the image screen from the small display device toward the eye of the wearer.
The concave reflection mirror has a curved surface characteristic such that the focal position of the concave reflection mirror comes near the pupil of the wearer's eye, and further, the sound from the small display device can be heard through the headphones. A headphone type image display device characterized by being configured. 2. A small display device is attached in the vicinity of an ear pad on one side of the headphone, with its image screen facing forward, and the headphone part to which the small display device is attached is moved substantially vertically about a center of rotation. Is attached to the tip of the movable arm, which is provided with a substantially L-shaped movable arm for reflecting the image screen from the small display device toward the eye of the wearer.
The concave reflection mirror has a curved surface characteristic such that the focal position of the concave reflection mirror comes near the pupil of the wearer's eye, and a relay optical system is arranged between the small display device and the concave reflection mirror. Further, a headphone type video display device characterized in that the sound from the small display device can be heard through the headphone. 3. A small display device is attached in the vicinity of an ear pad on one side of the headphone, with its image screen facing forward, and the headphone part to which the small display device is attached moves substantially vertically about the center of rotation. Is attached to the tip of the movable arm, and an elliptical reflection mirror that reflects the video screen from the small display device toward the eye of the wearer is attached to the small display device. Two groups of lens systems are arranged between the elliptical reflection mirrors, in which case the elliptical reflection mirror and the lenses of the two groups are arranged to form a relay optical system, and the first focal point of the ellipse mirror is arranged. Has a curved surface characteristic such that the second focus is located near the center of the lens of the second group of lenses close to the elliptical reflection mirror, and the second focus is located near the pupil of the eye of the wearer. A headphone type video display device, characterized in that the sound from the display device can be heard through the headphones. 4. A small display device is attached near one of the ear pads on one side of the headphone with the image screen thereof facing forward, and the headphone part to which the small display device is attached is moved about in the vertical direction. Is attached to the tip of the movable arm, which is provided with a substantially L-shaped movable arm for reflecting the image screen from the small display device toward the eye of the wearer.
The concave reflection mirror has a curved surface characteristic such that the focal position of the concave reflection mirror is near the pupil of the wearer's eye, and an optical fiber array optical system is arranged between the compact display device and the concave reflection mirror. Furthermore, a headphone type video display device characterized in that the sound from the small display device can be heard through the headphones. 5. The parabolic mirror according to claim 1, wherein the concave reflection mirror is a parabolic mirror having a focal length such that the focal point is near the pupil of the wearer's eye. Headphone type video display device. 6. The headphone type image display device according to claim 1, wherein the small display device is a liquid crystal display device.