JP3333165B2 - Head mounted video display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a head mounted image display device.

[0002]

2. Description of the Related Art Conventionally, a head-mounted type that is held on the observer's head for the purpose of enjoying a large-screen image by an individual or to be able to carry the image outdoors and view the image. Video display devices have been devised. For example, FIG. 7 is an example of a conventional head-mounted image display device, and is a partial cross-sectional view showing a state where an observer is using the image display device. In the head-mounted image display device 101, an image display element 102 mounted on the observer's head and arranged in front of both eyes,
It has a sound reproducing element 103 for reproducing sound. The video display element 102 and the audio reproduction element 103 are composed of a video signal supply code 104 and an audio signal supply code 1.
05 is connected to a video / audio signal supply unit (not shown).

[0006] A projection optical system 107 is mounted in the apparatus opening 106 at a position near the face of the image display element 102. The projection optical system 107 is arranged at a predetermined distance from the image display element 102 so that the image displayed on the image display element 102 is enlarged and projected into the eyeball 108 of the observer. With such a head-mounted image display device, the power of a large-screen image can be obtained with a small-sized image display element, and the image can be enjoyed in a comfortable posture of an observer without giving image information to the surroundings. However, since the eye width of the observer varies from person to person, the image projected by the projection optical system 107 may not be able to be properly guided into the eyeball 108 in some cases.

For this reason, in Japanese Utility Model Laid-Open No. 2-82175, Japanese Patent Application Laid-Open No. 4-26288 and Japanese Patent Application No. 4-267504, the projection optical system for the right eye and the left eye of the projection optical system is adjusted according to the individual difference between the two eyes. A head mounted video display device in which the distance between the exit pupils can be adjusted has been devised. On the other hand, since the head-mounted image display device is worn on the observer's head, it is necessary to reduce the size and weight of the image display element in order to reduce fatigue and prevent danger, and mainly uses liquid crystal.

[0005]

However, an image display device using this liquid crystal has a viewing angle dependency. In other words, generally, light emitted in a direction within about 5 degrees from the normal direction of the liquid crystal display has a high contrast, so that a good image can be obtained. In other places, a good image can be obtained. It will be difficult.

That is, as shown in FIG. 8, since the numerical aperture of the light emitted from the video display element 102 is small, the diameter of the exit pupil of the exit pupil 109 by the projection optical system 107 is limited. In addition, if an attempt is made to increase the light condensing property of the light from the image display device using a lens system or the like in order to increase the amount of light guided to the eyeball, the exit pupil is limited to a small size.

Therefore, in order for the observer 110 to obtain a good image, it is necessary to receive light for obtaining a good image over the entire surface of the left and right pupils 111 and 112 of the observer. The observer's pupil must be placed in the area where good light intersects. FIG. 8 shows the observer 1
Since the left eye pupil 111 overlaps the exit pupil 109, a good image is observed with the left eye, but the right eye pupil 1
Reference numeral 12 is shifted from the exit pupil 109, and a good image cannot be observed with the right eye, and a state in which binocular vision cannot be performed is shown.

In general, the observer does not know whether or not the observer is observing with both eyes, and in order to confirm that, the observer must close one eye and confirm whether or not the observer can observe both eyes.
In addition, it is difficult to know in which direction the device should be adjusted when the pupil is shifted. Therefore, the observer must perform complicated pupil alignment when using the head-mounted image display device.

In view of the above-mentioned problems of the prior art, an object of the present invention is to eliminate the display of the pupil shift instruction after the pupil alignment operation is completed, to eliminate the display that hinders image observation, and to reduce power consumption. Another object of the present invention is to provide a head-mounted image display device that also takes into account prevention of the problem.

[0010]

[0011]

In order to solve the problems of the prior art, a head mounted image display device according to the present invention comprises an image display element for displaying an image, and an image display device for displaying the image on an eyeball of an observer. A head mounted image display device comprising: a projection optical system for projecting the image into the head mounted image display device, wherein the head mounted image display device comprises: A pupil shift instruction light beam for causing the observer to recognize a pupil shift generated between the projection pupil position and the exit pupil position. The head-mounted image display device is disposed so as to pass through the periphery of the system, and includes control means for switching between generation and disappearance of the pupil displacement instruction light beam. It is characterized by performing.

[0012]

[0013]

According to the configuration of the present invention, the pupil shift instruction display image projected on the observer's eyeball through the projection optical system is viewed by the observer before normal image observation, and the pupil shift is adjusted. ,
After the adjustment, after the pupil shift instruction display disappears, normal video observation can be performed.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the head mounted image display device according to the present invention will be described below. First, a first embodiment of the present invention will be described with reference to FIG. The present embodiment is an example in which a transmission lens is used as the projection optical system 1. Further, the pupil shift instruction unit 2a is arranged on the lens surface closest to the eye of the projection optical system 1.

The pupil shift instructing section 2a is arranged in an annular shape so that a light beam necessary for obtaining a good image from the liquid crystal display element 3 comes into contact with the outside of the image forming light beam 5 up to the exit pupil 4. I have. The pupil shift instruction unit 2a is formed of red cellophane here. The light beam with high contrast emitted from the liquid crystal display element 3 passes through the exit pupil 4 formed by the projection optical system 1. By placing the pupil of the observer near the exit pupil 4, an image can be formed on the retina in the eyeball of the observer.

The pupil shift instruction unit 2a receives a light beam from the liquid crystal display element 3 passing outside the image forming light beam 5, and the light beam transmitted through the pupil shift instruction unit 2a is converted into a red pupil shift instruction light beam 6, It passes near the outside of the exit pupil 4. Since the pupil shift instruction light beam 6 is guided into the eyeball when the pupil of the observer's eyeball does not overlap the exit pupil 4, the observer knows that the pupil of the eyeball does not match the exit pupil 4. .

The feature of this embodiment is that the observer can be notified that the pupil is shifted with a very simple configuration. The observer only needs to adjust the apparatus so that the red light due to the pupil shift instruction light beam 6 cannot be seen. Here, red cellophane was used as the pupil shift indicator, but the present invention is not limited to this, and filters of other colors, dichroic filters, dichroic mirrors, filters with only a few holes, etc. are used. Is also good. Further, the outer side of the image forming light beam may not be in contact with the outer side of the image forming light beam. Further, in addition to the configuration arranged in a ring shape, a configuration may be adopted in which the image forming light beam is disposed at some desired locations around the light flux. Also, an example has been shown in which the pupil shift instruction unit 2a is arranged on the lens surface closest to the eye of the projection optical system 1. However, the arrangement of the pupil shift instruction unit is not limited to this position. But
Alternatively, the lens may be colored to serve as a pupil shift instruction unit.

When observing an image with both eyes, in order to know whether the exit pupil for the right eye or the left eye is shifted, the pupil shift instruction unit 2a for the right eye and the left eye is used. Thus, a configuration in which a different color is used may be adopted.

A second embodiment of the present invention will be described with reference to FIG. As in the first embodiment, this embodiment is also an example in which a transmission lens is used as the projection optical system. The same components as those in the first embodiment are denoted by the same reference numerals and description thereof is omitted. The difference from the first embodiment is that the pupil shift instruction light beam 6 from the pupil shift instruction unit 2b is provided with a separate optical path without using the light beam from the liquid crystal display element 3.

The pupil shift instruction section 2b is composed of an instruction display section 7 for displaying an arrow, an instruction display projection lens 8 and a mirror of an instruction display reflecting member 9. The instruction display unit 7
For example, an arrow printed on a screen is used. The light beam emitted from the instruction display unit 7 is used as a pupil shift instruction light beam 6 via a mirror of the instruction display projection lens 8 and the instruction display reflecting member 9 in the pupil shift instruction unit 2b. Here, external light is used as a light source for emitting light from the back of the instruction display unit 7.

As described in the first embodiment, the pupil shift indicating light beam described above is located near the outside of the exit pupil 4 of the image forming light beam 5 emitted from the liquid crystal display device 3 generated by the projection optical system 1. Pass through 6. By projecting the arrow of the instruction display unit 7 guided by the pupil shift instruction light beam 6 into the eyeball of the observer, the observer is notified of which direction to adjust the apparatus when the pupil shifts. Can be.
The observer need only look at this display and adjust the device.

Further, the image of the image guided into the eyeball and the image of the instruction display unit 7 can be simultaneously viewed at the focal point by the focal length of the instruction display projection lens 8, and the adjustment of the apparatus is facilitated. What is indicated by the instruction display unit 7 may be a symbol indicating up, down, left, or right in addition to the arrow. As a light source for emitting light from the back of the instruction display unit 7, another light bulb may be used.
A configuration other than those described here, such as a light emitting element such as an ED or an array of light emitting elements, may be used. Alternatively, a plasma display or the like in which the instruction display unit 7 emits light may be used.

After the adjustment of the interpupillary distance, the pupil shift instruction light beam 6 becomes unnecessary, so that the pupil shift instruction light beam can be turned off during normal observation by performing operations such as turning off or blocking the illumination light. Although a mirror is used as the instruction display reflecting member here, the present invention is not limited to this, and a prism may be used. Alternatively, the instruction display unit 7 may use a decentered optical system or the like to utilize the prism action. May be bent. Further, the pupil shift instruction unit may be inclined such that the light flux from the instruction display unit becomes the pupil shift instruction light beam without using the instruction display reflection member. Also, an instruction display projection lens is not particularly required.

The pupil shift instructing section 2b does not need to contact the outside of the image forming light beam 5 and may be in the vicinity thereof, and may be arranged at some desired locations around the image forming light beam 5 as in the first embodiment. Is fine. Further, as in the first embodiment, when observing an image with both eyes, in order to know which of the exit pupils for the right eye and the left eye is shifted, the right and left eyes of the pupil shift instruction unit 2b are used. Use different colors for left eye, left and right, LR on instruction display 7
May be displayed.

A third embodiment of the present invention will be described with reference to FIG. The present embodiment is an example in which a reflective concave mirror 10 is used in an eyepiece as the projection optical system 1. Here, the plasma display 11 is used as an image display element. Further, a pupil shift instruction unit 2c is arranged near the pupil position of the projection optical system 1. In the case of the present embodiment, the pupil shift instruction unit 2
The light bulb 12 is used as a light source used for c. Further, the reflecting member 13 in the pupil shift instruction unit 2c has a configuration in which one end surface of a transparent plastic prism is cut obliquely.
The light from the bulb 12 is reflected and guided into the projection optical system 1 to form a pupil shift instruction light beam 6.

The angle of the cut portion of the reflecting member 13 is adjusted so that the pupil shift instruction light beam 6 becomes parallel to the optical axis near the exit pupil 4. Light emitted from the plasma display 11 is transmitted through the projection optical system 1 and reflected by the reflective concave mirror 10 in the projection optical system 1 to form the exit pupil 4. Further, by adjusting the angle of the cut portion of the reflection member 13, the pupil shift instruction light beam 6 becomes parallel to the optical axis in the vicinity of the exit pupil 4, so that even if the pupil position of the observer is shifted in the optical axis direction, the pupil shifts. Although the deviation indicating light beam 6 does not enter the eye and is not bothersome, when the observer's pupil position is displaced from the exit pupil 4 of the projection optical system 1 in the lateral direction (within the XY plane in the drawing) with respect to the optical axis. The displacement indicating light beam 6 is guided into the eyeball.

In this embodiment, the light bulb 12 is used as the light source used for the pupil shift instruction section 2c. However, similarly to the second embodiment, the configuration of the external light, the light emitting element such as the LED, the array of the light emitting element, etc. May be used. In the case of the present embodiment, the same effect can be obtained by using the decentered optical system, optical fiber, or the like shown above instead of the reflecting member 13 in the pupil shift instruction section 2c.

A reference example will be described with reference to FIG. This reference example is also an example in which a reflective concave mirror 10 is used for the eyepiece as the projection optical system 1 as in the third embodiment, and a pupil shift instruction unit 2d is arranged near the pupil position of the projection optical system 1. Things.
The pupil shift instruction unit 2d serves to guide the light from the light bulb 13, the light receiving element 14, and the light bulb 13 into the projection optical system 1 and the light returning to the pupil shift instruction unit 2d to the light receiving element 14. It is composed of a half mirror 15 and a mirror 16. Here, the liquid crystal display element 3 is used as the image display element.
Is used.

The feature of the present embodiment is that the observer operates the pupil indicating light beam 6
Instead of adjusting the exit pupil 4 of the projection optical system 1, the image formed by the light beam reflected by the observer's eye is adjusted by the pupil shift instruction unit 2.
d, the light is received by the light receiving element 14 and the apparatus automatically adjusts the exit pupil 4 to the position of the pupil of the observer using the pupil shift correction mechanism 17 of the apparatus.
Is to match. At the pupil position of the projection optical system 1, the light beam reflected by the observer's eyes forms an image, and an image as shown in FIG. 5 is formed. If the pupil shift instruction unit 2d including the light receiving element 14 is arranged here, it is possible to monitor the brightness of the image near the eyes of the observer. Generally, human skin, the white eye, and the iris have high reflectivity, so that the images formed at the pupil position earlier are bright, and the retina seen through the observer's pupil has low reflectivity, and the formed image is dark. ing. The difference in brightness of the image is read by the light receiving element 14.

The pupil shift instructing unit 2 having the light receiving element 14
By arranging a plurality of ds in the vicinity of the previous pupil position and sending the signal of the light receiving element 14 to the pupil shift calculating device 18, the direction of the exit pupil 4 on the device side with respect to the observer's pupil and in which direction It can be calculated whether it is shifted. Based on the calculation result, the apparatus can be automatically moved by the pupil shift correcting mechanism 17 so that the exit pupil 4 can be superimposed on the pupil of the observer. As a method of correcting the pupil deviation, for example, a method of moving the entire image display device for the right eye or the left eye,
A method of tilting the reflecting concave mirror 10 of the projection optical system 1, a method of decentering a part of the lens of the projection optical system 1, a liquid crystal display element 3
And a method of inclining the optical axis of light emitted from a light source (not shown) provided at the rear of the camera.

Further, among the adjusting mechanisms for correcting the direction and amount of displacement of the exit pupil 4 and the amount of misalignment, among the several adjustment mechanisms,
Information on which adjustment mechanism should be adjusted can be displayed on, for example, the liquid crystal display element 3 and guided to the observer's eyeball to be informed.

FIG. 6 is a view showing a fourth embodiment of the present invention. The arrangement of the projection optical system 1 and the liquid crystal display element 3 is basically the same as that of the third embodiment and the reference example, and thus the description is omitted.

Here, the reflecting concave mirror used for the eyepiece of the projection optical system 1 is constituted by a half mirror 19. Then, as shown in FIG.
The pupil shift instruction light beam 6 is arranged along the outside of the imaging light beam 5 and passes near the outside of the exit pupil 4. The pupil shift instruction light beam 6 can notify the observer that the pupil is shifted.

As described above, the pupil shift instructing unit includes the projection optical system 1.
Therefore, it is not necessary to provide the pupil shift instruction unit in the vicinity of the image forming light beam 5, so that the pupil shift instruction unit can be arranged by the above configuration regardless of the production restriction such that the pupil shift instruction unit cannot be arranged near the imaging light beam 5. Further, since the reflecting concave mirror used for the eyepiece section is the half mirror 19 as described above, the pupil shift indicating light beam 6 passes in parallel near the exit pupil 4 as in the third embodiment and the reference example. They can also be placed.

Further, even if the reflecting concave mirror used for the eyepiece of the projection optical system 1 is not the half mirror 19, the surface on which the image forming light beam 5 strikes is mirror-like, and the outer surface thereof is the pupil shift indicating light beam 6. The mirror may be configured to transmit light, or may be configured to simply transmit the pupil shift instruction light beam 6 to the outside of the concave mirror. Of course, the location of the half mirror 19 is not limited to this location, and can be located at any location in the optical path.

[0036]

As is apparent from the above description, according to the present invention, after the pupil alignment operation is completed, the pupil shift instruction display is turned off to eliminate the display that hinders image observation and to reduce power consumption. It is possible to provide a head-mounted image display device which also realizes the prevention of the above.

[Brief description of the drawings]

FIG. 1 is a side view of a main part showing a first embodiment of the present invention.

FIG. 2 is a main part side view showing a second embodiment of the present invention.

FIG. 3 is a main part plan view showing a third embodiment of the present invention.

FIG. 4 is a main part plan view showing a reference example of the present invention.

FIG. 5 is a diagram showing an image formed at a pupil position in a reference example of the present invention.

FIG. 6 is a plan view of a main part showing a fourth embodiment of the present invention.

FIG. 7 is a partial cross-sectional view showing a state in which an observer is using the conventional head-mounted image display device.

FIG. 8 is a schematic plan view showing a state where the exit pupil of the head-mounted image display device and the pupil of the observer are shifted.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 5/64 511 G02B 27/02 H04N 13/04

Claims (1)

(57) [Claims] And 1. A video display device for displaying an image, and a projection optical system for projecting into an observer's eye to the video head
A head mounted video display device, wherein the head mounted video display device
Between the pupil position of the observer and the exit pupil position of the projection optical system
Pupil for allowing the observer to recognize the pupil shift occurring between
The luminous flux generating means having a shift instruction light beam and generating the pupil shift instruction light beam is provided with the pupil shift
So that the indicating light beam passes through the periphery of the projection optical system.
And the head mounted image display device emits the pupil shift indicating light beam.
A control means for switching the disappearance raw, after adjustment of the pupil misalignment, the head-mounted image display apparatus which is characterized in that the disappearance of the light beam.