JP2005202221A - Display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device made compact and excellent in portability, realizing high visibility and having wide field. <P>SOLUTION: A light projection surface comprising a 1st field area equivalent to a center area and a 2nd field area equivalent to a circumferential area is scanned with 1st and 2nd light beams in a horizontal direction and a vertical direction to display a synthetic image. The 1st and the 2nd light beams are turned from 1st and 2nd two-dimensional scanners. In the 1st and the 2nd two-dimensional scanners, the corresponding light beam is deflected in a 1st direction to perform scanning in a 1st optical scanning part and is condensed in a 2nd scanning part, and the deflected light beam is deflected in a 2nd direction to perform scanning in the 2nd scanning part. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a display device, and more particularly to a display device that provides a wide field of view.

  In order to obtain a high sense of realism, a display having a wide viewing angle comparable to the human naked eye observation is required. In general, it is said that a human's viewing angle in naked-eye observation is 100 degrees left and right (200 degrees in total), 50 degrees above and 75 degrees below (125 degrees in total). Within this field of view, the field of view (stable focus field) that can be taken as visual information without difficulty by head movement and eye movement is about 80 degrees left and right as described in Non-Patent Document 1. It is about 70 degrees. In addition, with regard to such a human visual field, the region where the effect of presence at a wide viewing angle is saturated is 50 degrees left and right (a total of 100 degrees), 35 degrees above and 50 degrees below (same as a stable focus field) ( It is known in Non-Patent Document 2 that the total is 85 degrees) (guidance visual field).

  On the other hand, although the human visual field is greatly expanded as described above, the field of view that can be observed with the highest resolution is an area of about 5 ° in diameter at the center of the visual field (discrimination visual field). The field of view (effective field of view) that can accept information is said to be about 30 ° in total on the left and right and about 20 ° on the vertical.

  At present, various types of projection type display devices are known as display devices that realize a high sense of reality represented by virtual reality display, and the projection type display devices are widely used. Various projection displays can easily realize a wide field of view corresponding to the guidance viewing angle such as 100 degrees left and right and 85 degrees above and below the panel direct-view display devices such as CRTs, liquid crystal devices, and plasma display devices. .

  The existing direct-view display panel is at most about 60 inches diagonal at present, and the resolution of the panel display having such a large screen is about 720p and is equivalent to HDTV. Therefore, even if a visual field equivalent to the guidance visual field is secured with a single panel, not only the display resolution is extremely lowered, but the viewing distance of the observer is extremely close to the panel surface, which places a heavy burden on the observer. become. In order to secure the viewing distance of the observer and to achieve sufficient resolution, it is necessary to make a large screen using a large number of panels. In order to obtain such a wide viewing angle, a considerable number of panels need to be used, and even if a series of flat panel displays, which are said to be relatively small in volume, are used, the cost increases and the installation scale increases. Is needed.

  In contrast to this direct-view display panel, the projection display device is in a state where a device having a projection scale of about 100 inches diagonal can be easily obtained as a single device. The projection display device has a resolution itself that is not so different from that of a direct view panel display, and even if compared with a direct view display that directly views a self-luminous light emitting panel, Although the reflected light is observed, a display that does not give a sense of incongruity is possible. Moreover, even when a wide viewing angle image is obtained using a plurality of projection type devices, the projection device itself is a device that does not become a burden, and it is possible to construct a system more easily than using a panel display. It is.

  As an example of constructing a highly realistic display device using a projection display device, an all-around display device such as CAVE or CAVIN is famous. This is a device that projects the image in all directions from the back of the screen to each side by using a projection type display device (the lower surface is the viewer side, Projected from above the screen).

  Such an all-round display device is composed of a projection display device and a screen depending on the projection surface, and is simple but the screen for a single viewer is about a small room, and the room is configured. Since there is also a space necessary for projection on the back of the screen, the entire system configuration is large and the installation time is one to several days.

For such a large-scale all-round display device, there is a group of display devices called head mounted displays (HMD) using a liquid crystal panel or the like. A head-mounted display is a device that performs display in an observation field by facing a small panel display through an optical system arranged in front of the eyes. Usually, the HMD widely supplied to Ichii displays a field of view of about 30 degrees diagonal, which is the NTSC television level field of view, and its display area is not at a level that can produce a high sense of presence. Some have already been in this field and have a field of view of about 100 degrees left and right for binocular observation. However, a high-quality image cannot be obtained because the resolution of a single panel used is inferior. In addition, such a device for displaying a wide viewing angle often has a large distortion in the peripheral visual field due to the problem of the optical system.
Hatada Journal of Precision Engineering 1330, 57, 1991 Hatada et al., Journal of Television Society 407, 35, 1979

  As described above, various devices capable of displaying a wide viewing angle have been proposed, but there are problems such as impossible miniaturization, and even a display device capable of miniaturization has high resolution. There is a problem that wide viewing angle display cannot be realized.

    The present invention has been made in view of the circumstances as described above, and its purpose is to have an operating principle that makes it possible to make a compact device with excellent portability in the future. It is an object of the present invention to provide a small display device in which an observer does not feel discomfort when wearing the display device.

  In particular, an object of the present invention is to provide a device capable of providing a wide viewing angle display, providing a wide display range, and providing a high-resolution, distortion-free display that can be easily observed by a viewer.

According to this invention,
A light projection surface having a first direction and a second direction orthogonal to the first direction, and comprising a first region corresponding to the central visual field region and a second region corresponding to the peripheral visual field region;
A first light source that generates a first light beam; a first deflection unit that deflects the first light beam along the first direction; and the first light beam from the first deflection unit is collected. A first two-dimensional scan including a first condensing lens system and a second deflecting unit disposed at a focal point of the first condensing lens and deflecting the first light beam along the second direction. Equipment,
A second light source that generates a second light beam; a third deflector that deflects the second light beam along the first direction; and the second light beam from the third deflector is collected. A second two-dimensional lens system including a second condensing lens system and a fourth deflecting unit that is disposed at a focal point of the second condensing lens and deflects the second light beam along the second direction. An optical image is displayed on the light projection surface by directing the first and second light beams from the scanning device and the first and second two-dimensional scanning devices toward the first and second regions. An optical unit;
A display device is provided.

Moreover, according to this invention,
An optical image is displayed on a light projection surface that has a first direction and a second direction orthogonal to the first direction, and includes a first region corresponding to the central visual field region and a second region corresponding to the peripheral visual field region. In the method
The first light beam is deflected along the first direction, the first light beam is condensed, and the first light beam is converged at the condensing point of the first light beam along the second direction. Deflect,
The second light beam is deflected along the first direction, the deflected second light beam is condensed, and the second light beam is condensed at the second light beam condensing point along the second direction. Deflect the rays,
A display method is provided, wherein an optical image is displayed on the light projection surface with the first and second light rays directed toward the first and second regions.

    According to the present invention, it is possible to provide a display device and a display device that are small and have a wide field of view.

  Prior to the description of the display device according to the embodiment of the present invention, the points that the inventor leading to the present invention focused on will be described.

    In the present invention, a small optical scanning device disclosed in Japanese Patent Application No. 2003-193907 is used to realize a display device capable of wide viewing angle display capable of giving a high-resolution distortion-free display. . The optical scanning device disclosed in Japanese Patent Application No. 2003-193907 can optically expand the optical scanning range arbitrarily, and can display at an arbitrary viewing angle by projecting the scanning light beam onto the eyeball. It becomes. However, in the display with a wide viewing angle using a single scanning device, there is a problem that the amount of information per observation angle decreases as the field of view expands. The normal human visual acuity is assumed to be about 1, and the visual acuity 1 is 60 lines / deg as the eye resolution. If the resolution of about 60 lines / deg can be obtained, any observer can reproduce the definition in an image almost comparable to the naked eye observation. However, when considering the distribution of visual acuity in recent years, it is speculated that if a resolution of about 30 lines / deg corresponding to visual acuity 0.5 can be obtained, sufficient image quality can be given to many observers. The For example, as an embodiment of the display device, it is assumed that in the above-described optical scanning device, the primary scanning device is operated at a primary scanning frequency of about 25 kHz and the two-dimensional scanning device is operated at a two-dimensional scanning frequency of 60 Hz. Then, the two-dimensional image formed by this apparatus has a frame rate of 60 flame / sec when raster scanning is used. This frame rate is the same as the two-dimensional scanning frequency. The primary scanning frequency is a value related to the amount of information in the scanning line, but in principle, infinite information can be given by analog data reproduction. As a result, the number of scanning lines is a direct factor in the resolution of the visually recognized image. Considering a primary scanning frequency of 25 kHz and a two-dimensional scanning frequency of 60 Hz, if scanning light in the forward, backward, and both directions is used during primary scanning, the scanning light flux is 50 kHz, and scanning per frame at a two-dimensional scanning frequency of 60 Hz. About 800 lines can be provided. Considering the resolution per angle using the number of scanning lines, when the scanning line is scanned from the top to the bottom of the field of view (similar to a raster scan by a normal CRT), In the case of having a field of view, the scanning line resolution is about 27 lines (27 line / deg) per field angle. When the viewing angle is expanded to 60 degrees, the scanning line resolution is simply about 13 lines (13 line / deg) per degree.

  When such a scanning device is used to display an image for a field of view of about 100 degrees in the horizontal direction and 60 degrees in the vertical direction comparable to a human monocular field of view, the scanning line resolution is about 13 lines per degree. (13 line / deg). Such an image is an image unacceptable for an observer. Therefore, there is a need for a high-quality display method that can withstand the viewer's appreciation.

  Against this background, as a result of intensive studies, the inventor can display an image with a wide viewing angle by using a plurality of optical scanning devices for the display device, and solve the above-described problems. Has led to the idea that this is possible.

  As a method of displaying a wide viewing angle or a large screen with a plurality of display devices, a method such as tiling of a panel type display is generally used. In this tiling, a display device having a large screen (or a wide viewing angle) as a whole is realized by arranging a plurality of panels so as to be tiled. In tiling, it is possible to easily make a display device with a large screen and a high viewing angle, but the seam between the panels that are bonded together is conspicuous, and it is very important to match the display characteristics such as the color tone of the panels. Labor is required.

  On the other hand, the display device of the present invention can be downsized by combining a small optical scanning device, and can display a wide scanning range. The optical scanning device can display a wide scanning range that can complement the effective visual field of human beings alone, but usually scans with high resolution to the periphery of the effective visual field required for high-definition human observation. In the peripheral field of view that corresponds to the expression of other high sense of reality and does not need to be displayed with a very high definition, it is displayed with a resolution suitable for it. Therefore, according to the display device of the present invention, super-realistic display can be easily performed.

  A display device according to an embodiment of the present invention will be described below with reference to the drawings.

  FIG. 1 is a plan view schematically showing a planar arrangement relationship in a display device according to an embodiment of the present invention. The display device shown in FIG. 1 includes a first two-dimensional optical scanning device 10 and a second two-dimensional optical scanning device 20. The first and second two-dimensional optical scanning devices 10 and 20 include a one-dimensional optical scanning unit 11 and a condenser lens 12 and a two-dimensional scanning unit 13 as will be described in detail later with reference to the drawings. , 23 and two-dimensional scanning units 11, 21 are configured to drive motors 14, 24 for tilting. The first and second two-dimensional optical scanning devices 10 and 20 are arranged so that their optical axes OP1 and OP2 are orthogonal to each other, and a transflective device 30 is arranged on this optical axis, and its semi-transmissive The transflective device 30 is arranged such that the reflecting surface forms 45 degrees with respect to both the optical axes OP1 and OP2, and the both optical axes OP1 and OP2 are orthogonal to each other on the transflective surface.

  The first two-dimensional optical scanning device 10 emits the first two-dimensional scanning light beam L1, is reflected by the semi-transmissive reflective surface of the semi-transmissive reflective device 30, and is directed to the projection surface. On the other hand, the second two-dimensional optical scanning device 20 emits the second two-dimensional scanning light beam L2, passes through the transflective device 30, and follows the optical path of the first two-dimensional scanning light beam L1. Is directed to the projection surface. Here, the second two-dimensional scanning light beam L2 forms an optical scanning image 42 for a wider viewing angle on the projection surface, and the first two-dimensional scanning light beam L1 has a narrower viewing angle on the projection surface. The optical scanning image 41 is formed. When the second two-dimensional scanning light beam L2 scans the optical scanning image 41, the second two-dimensional scanning light beam L2 is blanked without being generated.

  Therefore, the first optical scanning image 41 formed by the first two-dimensional optical device 10 and the second optical scanning image 42 formed by the second two-dimensional optical scanning device 20 are synthesized on the projection surface. Thus, a composite image 40 is formed. Here, the first optical scanning image 41 corresponds to the periphery of an effective visual field required for high-definition human observation, and is scanned and displayed with high resolution. On the other hand, the second optical scanning image 42 corresponds to a peripheral visual field that does not need to be displayed with high definition, and is displayed with a lower resolution than the first optical scanning image 41. As described above, when the synthesized image 40 is visually recognized by the first and second optical scanning images 41 and 42, an image full of realism is recognized over a wide field of view from the characteristics of the human field of view.

Here, the optical scanning image 41 is defined to be an area having a diameter of about 5 ° (discrimination visual field) at the center of the visual field with reference to the eyes of the observer, and a visual field (effective visual field) that can receive information instantaneously only by eye movement. May be set to 30 ° in total from left to right and 20 ° in total from top to bottom or within that range. The second optical scanning image 42 is about 50 degrees left and right (100 degrees in total), 35 degrees above and 50 degrees below (85 degrees in total) (guide visual field) or this value. In the two-dimensional optical scanning apparatus shown in FIG. 1 defined above, the scanning angle of the second two-dimensional scanning light beam L2 is larger than the scanning angle of the first two-dimensional scanning light beam L1. The scanning angles of the second two-dimensional scanning light beams L1 and L2 are set by appropriately setting the lens characteristics of the first and second condenser lens systems 12 and 22 used in the two-dimensional optical scanning devices 10 and 20, respectively. Has been. Specifically, the first and second condenser lens systems 12 and 22 are configured by first and second lenses, respectively, and the first lens disposed on the optical scanning units 11 and 21 side is one-dimensional. The first lens has a focal length such that the rear focal point is located at the position of the light emission source that can be regarded as a single light source in the optical scanning units 11 and 21, and scanning from the emission source of the optical scanning units 11 and 21 is performed by this first lens. Light is converted into a parallel beam. The first lenses arranged in the first and second condenser lens systems 12 and 22 are given optically identical lens characteristics. The parallel light beams emitted from the first lens are condensed toward the two-dimensional scanning units 13 and 23 by the second lenses of the condenser lens systems 12 and 22, respectively, and tilted by the driving motors 14 and 24, respectively. The projection surface is scanned at different scanning angles by the two-dimensional scanning units 13 and 23. Here, in the first condensing lens system 12, the second lens has a long focal point with a relatively long focal length, and the second condensing lens system 22 is used for scanning the light beam at a wider angle. A short focus system having a shorter focal length than the second lens of the condenser lens system 12 is used.

  The two-dimensional scanning units 13 and 23 deflect the light beam from the second lens of the first and second condenser lens systems 12 and 22 and scan the projection surface with the deflected light beam. Here, when the second lens of the second condenser lens system 22 has a shorter focal length than the second lens of the first condenser lens system 12, the two-dimensional scanning units 13, 23 are used. Even if the light beam is deflected with the same minute deflection angle, the two-dimensional scanning unit 23 scans the light beam over a wider range (with a wide field of view) than the two-dimensional scanning unit 13.

  The two-dimensional scanning units 13 and 23 are synchronized with the vibration period in the primary direction (horizontal direction) of the cantilever structure 31 provided in the optical scanning devices 10 and 20, and are a polygon mirror, a galvano mirror of about 5 mm square, The optical path of the acousto-optic device is tilted by motors 14 and 24 controlled by a control circuit (not shown). By tilting the two-dimensional scanning units 13 and 23 in synchronism with the cantilever structure 31, the cantilever structure 31 vibrates and performs primary scanning (corresponding to horizontal scanning) and the two-dimensional scanning unit 13. , 23 is subjected to secondary scanning (corresponding to vertical scanning). Accordingly, the light beam emitted through the two-dimensional scanning units 13 and 23 is converted into a light beam deflected two-dimensionally (corresponding to horizontal and vertical scanning). For example, when the two-dimensional scanning units 13 and 23 are tilted at 1800 rpm by the motors 14 and 24, two-dimensional scanning with a sweep frequency equivalent to 60 Hz is possible.

  The projection image 40 formed by the two optical scanning devices 10 and 20 is obtained by the optical scanning image 41 and the second two-dimensional optical scanning unit 23 formed by the first two-dimensional optical device unit 13 as described above. It is a composite image of the optical scanning image 42 to be formed. Therefore, the optical scanning images 41 and 42 are required to be formed on the same projection surface. Thus, in order to make the optical scanning images 41 and 42 coincide on the projection surface, it is required that the focal positions of the light beams constituting the respective projection images 41 and 42 are always arranged at the same optical distance. The For this reason, in the optical system shown in FIG. 1, the distance between the two-dimensional scanning units 13 and 23 in which the light source images of the two-dimensional optical scanning devices 10 and 20 are formed as virtual images and the transflective device 30 becomes equal. Thus, the two-dimensional scanning units 13 and 23 and the transflective device 30 are arranged.

  In the above description, the focal lengths of the second condenser lenses of the condenser lens systems 12 and 22 are made different on the assumption that the two-dimensional optical scanning units 13 and 23 deflect the light beam at the same deflection angle. However, when the two-dimensional optical scanning units 13 and 23 have the same deflection speed, but deflect the light beam at different deflection angles, the focal length of the second condenser lens may be the same or an approximate value. good. If the two-dimensional optical scanning unit 13 deflects the light beam with a small deflection angle, an optical scanning image can be formed within a relatively narrow viewing angle, and the two-dimensional optical scanning units 13 and 23 can deflect the light beam with a large deflection angle. Thus, the optical scanning image 42 can be formed within a wide viewing angle.

  FIG. 2 shows a layout of the display device when the display device shown in FIG. 1 is specifically arranged. As shown in FIG. 2, the optical scanning devices 10 and 20 are vertically arranged on the side of the head of the observer 50. In FIG. 2, the other optical scanning device 10 is arranged so that the optical axes thereof are orthogonal to one optical scanning device 20. A transflective device 30 is disposed obliquely on the optical path of the light beam L2 from the optical scanning device 20, and the optical scanning device 10 is disposed so that the light beam L1 is incident on the transflective device 30. The light beams L1 and L2 incident on the transflective device 30 are combined by the transflective device 30 and directed to the reflective device 40 having a concave reflective surface disposed on the observer's line of sight as a divergent light beam. Yes. That is, the light beam L2 transmitted through the transflective device 30 and the light beam L1 reflected from the transflective device 30 are directed to the reflective device 40 disposed in front of the eyes of the observer 50 and reflected by the reflective device 40. The light is condensed toward the eyeball 55 of the observer 50. Therefore, the observer 50 can observe the composite image 40 with the light beam incident from the reflection device 40. According to the arrangement shown in FIG. 2, the observer 50 can observe an image display with a wide viewing angle by the display device attached to the observer 50.

When the image (two-dimensional light beam) is projected onto the retina surface of the eyeball 55 as shown in FIG. 2, the reflection device 40 can be realized by an optical system having a diffraction or reflection function in front of the observer's eyes. By designing the reflecting device 40 to have a spectacle shape, for example, the observer can make it difficult for the viewer to feel uncomfortable. The reflection device 40 is formed on a three-dimensional ellipsoid having two focal points using, for example, aluminum vapor-deposited plastic, and one of the focal points is matched with a condensing point of a light beam generated in the secondary scanning units 13 and 23. The other focal point is determined so as to match the pupil opening of the eyeball 55. By setting the focal point in this way, all the two-dimensional light beams formed by the optical scanning devices 10 and 20 can be imaged on the retina of the eyeball 55. In addition, when aluminum vapor deposition plastic is used, external light from the viewing direction cannot be taken in, but it can also be used as a display device that can be viewed through by using a holographic lens or the like for the reflection device 40. is there.

  The structure of the one-dimensional optical scanning units 11 and 21 incorporated in the optical scanning devices 10 and 20 shown in FIGS. 1 and 2 will be described with reference to FIGS.

  The one-dimensional optical scanning units 11 and 21 include an SOI substrate structure 51 that constitutes a light source element section as shown in FIGS. As shown in FIG. 5, in the SOI substrate structure 51, an optical element is formed on a silicon substrate 51-1 using a microfabrication technique used in a semiconductor process. That is, as shown in FIG. 6, a silicon oxide layer 51-2 is formed in a partial region on the silicon substrate 51-1, and a silicon active layer 51-3 is formed on the silicon oxide layer 51-2 to form an SOI substrate. A structure 51 is formed. On the silicon active layer 51-3, a light source element 36 composed of a semiconductor laser, a light emitting diode or the like is formed, and an optical waveguide structure 35 for guiding a light beam from the light source element 36, and a light beam from the light source element 36 is an optical waveguide structure. Condensing part structures 39-1 and 39-2 for condensing light 35 are formed. In the optical waveguide structure 35, an optical waveguide material is applied on an SOI substrate 51-1, and the applied optical waveguide material is exposed by a resist technique, and then is cut into an optical waveguide by RIE processing, so that a silicon oxide layer 51-2 is formed. By etching as a sacrificial layer, the movable part is formed by releasing the beam structure from the silicon substrate 51-1. As an example, a polymethacrylate resin is basically used as a constituent material of the optical waveguide structure 35. However, other typical optical waveguide materials include polycarbonate resins, polystyrene resins, polyolefins, and various metals. There are oxides, metal nitrides, and the like. In this example, the thickness of the optical waveguide structure 35 is about 10 μm, and the exit end of the optical waveguide has a cross-sectional shape of 10 μm square. From such a molding process, the optical waveguide structure 35 is reduced in a cone shape toward the base portion 35B of the needle-shaped waveguide portion 35A, and the needle-shaped waveguide portion 35A extends from the tip of the cone-shaped upper portion 35A. It is. Similarly, the silicon active layer 51-3 extends in a needle shape with a gap between the silicon active layer 51-3 and the silicon substrate 51-1 so as to support the needle-shaped waveguide portion 35A, and the silicon oxide layer 51 together with the needle-shaped waveguide 35A. -2 is formed in a cantilever structure 31 fixed to -2. The cantilever structure 31 has flexibility, and the tip has a free end. Therefore, the needle-shaped waveguide 35A also has flexibility, and the tip is defined as a free end. The free end is defined as the light emitting end. As an example, the cantilever beam structure 31 has a beam width of about 10 μm and a length of about 1300 μm.

  In the structure shown in FIG. 6, the light beam generated from the light source element 36 is condensed on the optical waveguide structure 35 by the condensing unit structures 39-1 and 39-2, and the condensed light beam is the optical waveguide structure. 35 is propagated through 35, introduced into the base 35B35B of the needle-like portion 35A intensively, and ejected to the outside from the tip 35C. Accordingly, the base portion 35B of the needle-shaped portion 35A of the optical waveguide structure 35 corresponds to the light spot of the light source element 36 in the display device shown in FIGS. As will be described later, the rear focal points of the first lenses of the condenser lens systems 12 and 22 are aligned with the base portion 35B of the needle-shaped portion 35A of the optical waveguide structure 35.

  The cantilever structure 31 supporting the needle-like portion 35A for deflecting the needle-like portion 35A of the optical waveguide structure 35 is connected to a deflection mechanism 38. In other words, in the deflection mechanism 38, the cantilever beam structure 31 is connected to the bellows spring structure 34, and both ends of the bellows spring structure 34 are connected to the comb drive mechanism 32. The bellows spring structure 34 is supported by the stabilization spring structure 33, and supports the cantilever structure 31 so that it can be finely displaced in the extending direction stably. The comb-shaped drive mechanism 32 and the stabilization spring structure 33 are fixed to the frame 60 of the one-dimensional optical scanning units 11 and 21, and a voltage is wired to the comb-shaped mechanism 32 from a control unit (not shown). Applied. In the comb-shaped mechanism 32, an electrostatic driving force is generated from the capacitance generated between the comb teeth according to the applied voltage, and the bellows spring structure 34 has this electrostatic driving force generated in the comb-shaped mechanism 32. Is transmitted to the cantilever 11. Further, the bellows spring structure 34 has a bellows structure, so that the small amplitude of the comb-shaped mechanism 32 is amplified, and the cantilever structure 31 has a relatively large arc shape in the horizontal direction as indicated by an arrow HD in FIG. It can be converted into amplitude fluctuations that are biased to. One side of the stabilizing spring structure 31 is connected to the frame 60 of the optical scanning units 11 and 21, and the operation is stabilized so that the interdigitated comb teeth of the comb-shaped mechanism 32 move vertically. The vibration speed (scanning speed) of the cantilever structure 31 is determined by the resonance frequency depending on the physical constants of the constituent members such as the bellows spring structure 34, the stabilization spring structure 31, and the comb-shaped mechanism 32 that constitute the deflection mechanism 38. It is done.

  When the deflection mechanism 38 operates, the needle-like portion 35A of the optical waveguide structure 35 together with the cantilever structure 31 is deflected in an arc shape in the horizontal direction. As a result, the needle-like portion 35A of the optical waveguide structure 35 is emitted from the tip 35C. Light rays are deflected in the horizontal direction. Therefore, the one-dimensional light scanning units 11 and 21 emit light beams that spread in a fan-sharp shape in the horizontal direction. A color display device is realized by preparing one-dimensional light scanning units 11 and 21 having light sources that individually generate red (R), green (G), and blue (B) light beams as light source elements 36, respectively. I can do it.

  As shown in FIGS. 1 and 2, in the one-dimensional optical scanning devices 10 and 20, correction lenses K1 and K2 are provided in front of the one-dimensional optical scanning units 11 and 21, respectively. In the correction lenses K1 and K2, as the needle-shaped portion 35A of the optical waveguide structure 35 is changed by the deflection mechanism 38, the tip 35C of the needle-shaped portion 35A is finely moved. Fluctuated. Correction lenses K1 and K2, for example, plano-convex lenses are provided to correct the variation of the emission point. The correction lenses K1 and K2 act as a kind of fθ lens, give aberration according to the position of the periodically changing exit point, and the light spot does not move on the base portion 35B of the needle-like portion 35A of the optical waveguide structure 35. As shown, correction is given to the light beam emitted from the exit point. By providing the correction lenses K1 and K2, a stationary light spot is positioned at the base portion 35B of the needle-like portion 35A of the optical waveguide structure 35, and the first condensing lens of the condensing lens systems 12 and 22 has The side focal point can be located at a stationary light spot located at the base portion 35B of the needle-like portion 35A of the optical waveguide structure 35.

  In the display device shown in FIG. 1, when a normal video signal is input to the image processing unit 70, the video signal is stored in a frame memory in the image processing unit 70 for each frame. The image processing unit 70 extracts the first image component corresponding to the first optical scanning image 41 from the image stored in the frame memory of the input unit and corresponds to the second optical scanning signal 42, and The second image component corresponding to the peripheral image is extracted in the same manner and stored in the frame memory of the output unit. The image processing unit 70 outputs a modulation signal and a scanning signal from the first image component to the first driving circuit 72, and the first driving circuit 72 generates a light source of the one-dimensional optical scanning unit 11 according to the modulation signal. A drive signal for driving the element 36 is generated, and a modulated light beam is generated from the light source element 36. Further, the first driving circuit 72 gives horizontal and vertical scanning motion signals to the one-dimensional optical scanning unit 11 and the secondary scanning unit 13 in accordance with the input scanning signal, thereby providing the one-dimensional optical scanning unit 11 and the secondary scanning. The unit 13 is operated to deflect light incident on these units 11 and 13. Similarly, the image processing unit 70 outputs the modulation signal and the scanning signal from the second image component to the second driving circuit 74, and the first driving circuit 42 responds to the modulation signal with the one-dimensional optical scanning unit. A drive signal for driving the 21 light source elements 36 is generated, and a modulated light beam is generated from the light source element 36. Further, the second drive circuit 74 gives horizontal and vertical scanning motion signals to the one-dimensional optical scanning unit 21 and the secondary scanning unit 23 in accordance with the input scanning signal, thereby providing the one-dimensional optical scanning unit 21 and the secondary scanning. The unit 23 is operated to deflect the light rays incident on these units 21 and 23.

  Accordingly, a light beam deflected in the horizontal direction is emitted from the one-dimensional light scanning units 11 and 21, and the light beam is deflected in the vertical direction by the two-dimensional scanning units 13 and 23 and directed to the transflective device 30. From the transflective device 30, the first and second two-dimensional scanning light beams L1 and L2 are directed to the projection surface. Therefore, the first optical scanning image 41 and the second optical scanning image 42 formed by the first and second two-dimensional optical devices 10 and 20 are combined on the projection surface to form a combined image 40. The

  As described above, according to the display device of the present invention, by providing the two-system optical scanning device, a wide field of view can be secured and display can be performed with high resolution for the observer.

1 is a plan view schematically showing a display device according to an embodiment of the present invention. FIG. 2 is an arrangement example diagram schematically showing an arrangement of devices and a light flux locus thereof in the specific example of the display device shown in FIG. 1. It is a top view which shows roughly the structure of the optical scanning unit integrated in the optical scanning apparatus shown by FIG. It is a top view which expands and shows a part of optical scanning unit shown by FIG. It is sectional drawing which expands and shows schematically the element part shown by FIG.3 and FIG.4. FIG. 4 is a plan view showing a specific example of the optical scanning device shown in FIG. 3.

Explanation of symbols

  10,20. . . Two-dimensional optical scanning device, 11, 21. . . One-dimensional optical scanning unit 12,22. . . Condensing lens, 13, 23. . . Two-dimensional scanning unit 14, 24. . . Drive motor, 30. . . Transflective devices, L1, L2. . . Two-dimensional scanning light beam, 36. . . Light source element 51. . . Substrate structure, 40, 41, 42. . . Optical scanning image, 31. . . Cantilever structure, 33. . . Stabilized spring structure, 34. . . Bellow spring structure, 35. . . Optical waveguide structure, 38. . . Power mechanism, K1, K2. . . Correction lens

Claims (5)

A light projection surface having a first direction and a second direction orthogonal to the first direction, and comprising a first region corresponding to the central visual field region and a second region corresponding to the peripheral visual field region;
A first light source that generates a first light beam; a first deflector that deflects the first light beam along the first direction; and the first light beam from the first deflector is collected. A first two-dimensional scan including a first condensing lens system and a second deflecting unit disposed at a focal point of the first condensing lens and deflecting the first light beam along the second direction. Equipment,
A second light source that generates a second light beam; a third deflector that deflects the second light beam along the first direction; and the second light beam from the third deflector is collected. A second two-dimensional lens system including a second condensing lens system and a fourth deflecting unit that is disposed at a focal point of the second condensing lens and deflects the second light beam along the second direction. An optical image is displayed on the light projection surface by directing the first and second light beams from the scanning device and the first and second two-dimensional scanning devices toward the first and second regions. An optical unit;
A display device comprising: The first and second deflection units are
A waveguide part for guiding light rays from the light source part, which has flexibility and includes a movable waveguide part that emits the first or second light ray from its free end;
A drive mechanism for moving the movable waveguide portion in a direction corresponding to the first direction and deflecting the first or second light beam along the first direction;
The display device according to claim 1, comprising:     The display device according to claim 1, wherein the first region corresponds to the vicinity of the center of the visual field in the observer, and the second region corresponds to the peripheral visual field of the observer.     The display device according to claim 1, wherein the display unit has a first focal point defined on the third and fourth deflecting units and a first focal point defined on an observer eyeball. An optical image is displayed on a light projection surface that has a first direction and a second direction orthogonal to the first direction, and includes a first region corresponding to the central visual field region and a second region corresponding to the peripheral visual field region. In the method
The first light beam is deflected along the first direction, the first light beam is condensed, and the first light beam is converged at the condensing point of the first light beam along the second direction. Deflect,
The second light beam is deflected along the first direction, the deflected second light beam is condensed, and the second light beam is condensed at the second light beam condensing point along the second direction. Deflect the rays,
A display method, wherein an optical image is displayed on the light projection surface by directing the first and second light beams toward the first and second regions.

Images