JP2010113172A - Beam scanning type display and method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To solve such the problem that when a display, such as an HMD (Head Mount Display), obliquely projects a laser beam to a deflecting means, a difference in resolution is caused depending on the positions of incidence to the deflecting means. <P>SOLUTION: The beam scanning type display includes: a light source that outputs a beam; a wavefront shape-changing means for changing the wavefront shape of a beam from the light source; a scanning means for scanning a beam from the wavefront shape-altering means; and a deflecting means by which the beam scanned by the scanning means is deflected in a direction going toward the eyes of a user. In the device, the scanning means has a beam cross-section changing means for changing the cross-sectional shape of the incident beam. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a display device such as an HMD (head mounted display).

  Conventionally, in a display device such as an HMD (head-mounted display), there is a method (hereinafter referred to as a laser scanning method) in which laser light is two-dimensionally scanned and directly drawn on the retina of the eye. (For example, refer to Patent Document 1). Laser scanning display devices include a retinal scanning display, a retinal irradiation display, a direct retina display, a laser scanning display, a direct-view display device, an RSD (Retina Scanning Display), and a VRD (Virtual Retina Display). ), Etc.

FIG. 1 shows an example of the structure of a glasses-type HMD. In FIG. 1, laser sources 101 and 110 for emitting laser light to a spectacle frame, wavefront changing means 102 and 109 for controlling the wavefront of the laser light, and scanning means 103 and 108 for scanning the laser light in a two-dimensional direction are mounted. Yes. The laser light is projected toward the spectacle lens by the scanning means, reflected by the deflecting means 104 and 107 provided on the surface of the spectacle lens, is incident on the user's eye, and forms an image on the retina. Here, a half mirror, a hologram optical element (HOE), or the like is used for the deflecting means 104 and 107, and the user can view both the outside scenery and the image drawn by the laser at the same time. . For the scanning means 103 and 108, a mirror device that scans laser light in a two-dimensional direction by vibrating a single single-plate mirror in a uniaxial or biaxial direction is used.
JP 10-301055 A

  In order to realize a high resolution in such a laser scanning display device, it is necessary to reduce the beam spot diameter on the retina. Since the human eye is a condensing lens, when a parallel laser beam (laser beam with an infinite curvature radius) is incident on the eye, the incident light is focused on a small spot on the retina. Therefore, it is possible to depict a high-resolution video on the retina. In order to make a beam incident on the user's eye into parallel light in a glasses-type laser scanning display device, a method of changing the beam waist position of the laser light in accordance with the movement of the scanning means is used. The beam waist is a place where the radius of the laser beam is minimized. In this specification, the beam waist position is treated as a distance from the scanning means to the beam waist. By changing the position of the beam waist of the laser beam in accordance with the location where the scanning laser beam from the scanning unit is incident on the deflecting unit, the laser beam traveling from the deflecting unit to the user's eyes can be converted into parallel light. FIG. 3 shows an example of the optimum beam waist position of the scanning laser light by the scanning means for making the laser light toward the user's eyes parallel light in the eyeglass-type display device. The deflecting unit 104 is a hologram mirror designed to collect light at the pupil position 305 of the user, and the scanning unit 103 obliquely enters the laser beam 304 with respect to this deflecting unit. At this time, the beam waist position of the laser beam is changed in accordance with the incident position of the laser beam 304 on the deflecting means 104. An example of an appropriate beam waist position of the laser beam 304 is shown by a line 301, and the beam waist position of the laser beam 304 is positioned on the line 301 even if the direction of the laser beam 304 changes due to the movement of the scanning unit 103. Control is performed as follows.

  In this way, by adjusting the beam waist position by the wavefront control means, the beam incident on the eye is adjusted to be parallel light, and high resolution is achieved by using a beam having a large diameter. Can do.

  However, in a glasses-type display device that is incident on the deflecting unit from a large angle, there arises a problem that the optimum beam diameter varies depending on the incident position on the deflecting unit.

  As shown in FIG. 3, the optimum beam waist position of the laser beam 304 varies greatly depending on the incident position on the deflecting means. Since the laser beam has a property of spreading as it moves away from the beam waist position, when the beam diameter on the scanning unit is constant, the beam diameter of the laser beam when entering the deflection unit increases as the beam waist position is farther from the deflection unit. Become. That is, the beam diameter when entering the deflecting means is greatly different between the nearest incident point 303 shown in FIG. 3 and the farthest incident point 302. Since parallel light with a larger beam diameter is focused on a smaller spot diameter on the user's retina, the laser light incident on the farthest incident point 302 on the retina than the laser light incident on the most recent incident point 303. There is a problem that the spot size is reduced, and there is a problem that a large difference is generated in the resolution drawn depending on the location on the retina.

  The outgoing beam from the deflecting means is affected by aberrations such as coma, astigmatism and spherical aberration due to the optical action of the deflecting means. In general, the influence of aberration that light receives from an optical system increases as the beam diameter increases. At the farthest incident point 302, the beam diameter when entering the deflecting means 104 is larger than that at the most recent incident point 303, so that the influence of aberration is greatly affected. Therefore, a phenomenon that the resolution is deteriorated due to the influence of aberration may occur.

  In Patent Document 1, no consideration is given to the optimum beam diameter according to the incident position on the deflecting means.

  SUMMARY OF THE INVENTION The present invention solves the above-described problems, and an object of the present invention is to prevent resolution degradation by appropriately changing the beam diameter in a beam scanning display device.

In order to solve the above-described conventional problems, a beam scanning display device of the present invention includes:
A light source that outputs a beam;
Wavefront shape changing means for changing the wavefront shape of the beam from the light source;
Scanning means for scanning the beam from the wavefront shape changing means;
Deflecting means for changing the beam scanned by the scanning means in a direction toward the user's eyes;
A beam scanning display device comprising:
The scanning means includes beam cross-section changing means for changing the cross-sectional shape of the incident beam.

  With this configuration, the laser beam near the beam waist position from the deflecting unit increases the beam diameter to improve the resolution, and the laser beam far from the deflecting unit reduces the beam diameter to minimize the influence of aberration. It becomes possible.

Also, it is a mirror that scans the beam by changing the tilt angle,
The beam cross-section changing means is a transmission hologram formed on the mirror.

  This configuration makes it possible to change the beam diameter without adding moving parts.

  The transmission hologram of the present invention comprises a central portion and a peripheral portion, and the peripheral portion has a higher transmittance for incident light from a specific angle than incident light from other angles.

  With this configuration, the beam diameter of the laser light can be changed in accordance with the operation of the scanning unit.

  Further, the peripheral portion of the present invention is configured such that when a beam having a beam waist position at a position close to the deflecting unit is incident on the deflecting unit, an incident angle at which the beam is incident on the scanning unit is incident on the deflecting unit. A beam having a beam waist position at a position far from the deflecting means has a higher transmittance than an incident angle incident on the scanning means.

  With this configuration, the beam diameter of a beam having a beam waist position at a position close to the deflecting unit can be increased, and the resolution on the retina can be improved.

  The peripheral portion of the present invention is characterized in that the width differs between a portion perpendicular to the horizontal scanning direction of the scanning means and a portion perpendicular to the vertical scanning direction of the scanning means.

  With this configuration, the spot size on the retina can be set independently in the horizontal direction and the vertical direction.

  Further, the peripheral part of the present invention is characterized in that the cross-sectional shape takes a trapezoidal shape.

  With this configuration, it is possible to reduce the range of the incident beam blocked by the peripheral portion and keep the beam diameter of the outgoing beam large.

  The transmission hologram of the present invention is characterized by only a peripheral portion having a hole in the central portion, and the peripheral portion has an angle selectivity that maintains a high transmittance with respect to an incident angle from a specific angle.

  With this configuration, it is possible to reduce the required hologram material and reduce the weight of the scanning means.

  When the beam waist position of the scanning laser beam is far from the deflection unit, the influence of the aberration is prevented by reducing the beam diameter, and when the beam waist position of the scanning laser beam is close to the deflection unit, the beam diameter is increased. This keeps the beam diameter large on the deflection means and improves the resolution.

  Embodiments of the present invention will be described below with reference to the drawings.

(Embodiment 1)
FIG. 1 shows a configuration diagram (a plan view and a side view) of a glasses-type HMD (head-mounted display) in Embodiment 1 of the present invention. FIG. 2 is a detailed view of a part of FIG.

  In the configuration diagrams of FIGS. 1 and 2, each component and its relationship are described.

  The light sources 101 and 110 output beams. As shown in FIG. 2, the output beam is a laser beam obtained by combining the laser beams output from the red laser light source 211, the blue laser light source 212, and the green laser light source 213, and the output from each color laser light source is appropriately set. By modulating, laser light of any color can be output. Furthermore, an image can be displayed on the retina of the user's eye by performing modulation in conjunction with wavefront shape changing means and scanning means described later.

  In FIG. 2, 211 is a red semiconductor laser light source, 212 is a blue semiconductor laser light source, 213 is an infrared semiconductor laser light source, and SHG (Second Harmonic Generation: Second Harmonic Generation) that converts infrared light into green. ) Although shown as a combination of elements, 213 may be a green semiconductor laser light source, or each light source may be a solid laser, liquid laser, gas laser, or light emitting diode.

  In FIG. 2, the laser light is modulated by each laser light source, but the means for modulating the light output from the laser light source may be used in combination with the laser light source to modulate the laser light.

  The light sources 101 and 110 may include the light detection means 214 in FIG. The light detection means can detect the user's line-of-sight direction by detecting the intensity of the reflected light from the cornea of the user's eye. Most of the beams deflected in the direction of the eye by the deflecting means are incident on the corneal surface obliquely, but the beam from the front with respect to the eyeball is incident perpendicular to the corneal surface. Since the reflectance is relatively high, the line-of-sight direction can be detected by detecting the intensity of the reflected light.

  The wavefront shape changing means 102 and 109 change the wavefront shapes of the beams from the light sources 101 and 110, respectively, so that the spot sizes of the beams deflected by the deflecting means 104 and 107 described later are within a predetermined range. To do.

  The “spot size” of the beam will be described below as a spot size on the retina of the user's eye, but may be a spot size on the pupil, a spot size on the cornea, or a spot size on the deflecting means. The spot size on the retina is the same as the pixel size to be displayed.

  The “wavefront shape” is a three-dimensional shape of a beam wavefront, and includes flat, spherical, and aspherical shapes.

  In FIG. 2, the focal length horizontal component changing means 201 and the focal length vertical component changing means 202 are arranged in series in the optical path, so that the horizontal curvature and the vertical curvature of the wavefront shape are independent. Can be changed. In 201, the curvature in the horizontal direction is changed by changing the distance between the cylindrical lens and the mirror. 202 uses a cylindrical lens arranged perpendicular to the 201 cylindrical lens to change the curvature in the vertical direction. Further, in both 201 and 202, the beam diameter is also changed with the change in curvature.

  In addition, if the curvature in the horizontal direction is changed more greatly than in the vertical direction, the change in the horizontal direction can be handled more greatly. Therefore, when the horizontal viewing angle of the screen is desired to be larger than the vertical viewing angle, the scanning means ( This is particularly effective when the horizontal incident angle of the beam from the scanning means to the deflecting means (described later) is larger than the vertical incident angle, as in an HMD that will be described later.

  In the present invention, the wavefront shape deflecting means controls the laser light to maintain the beam waist position shown in FIG. 3 by changing the horizontal and vertical curvatures of the laser light in accordance with the movement of the scanning means 103 and 108. Do.

  The wavefront shape changing means in FIG. 2 uses a cylindrical lens and a mirror to change the wavefront shape, but as other means, a liquid shape lens, a variable shape lens such as a liquid lens, an EO element (electro-optical conversion) Element) or the like may be used. In this case, it is not necessary to directly move the position of the lens or mirror, so that high-speed control is possible and the display device does not generate extra vibration.

  Scanning means 103 and 108 two-dimensionally scan the beams from the wavefront shape changing means 102 and 109, respectively. The scanning means is a single-plate small mirror that can change the angle two-dimensionally, and is a MEMS (Micro-Electro-Mechanical-System) micromirror. The details of the scanning means 103 and 108 in the present invention will be described later.

  The deflecting units 104 and 107 change the directions of the beams scanned by the scanning units 103 and 108, respectively, toward the user's eyes. In the deflecting means 104 and 107, for example, a photopolymer layer is formed on the inner side (eye side) of the spectacle lens, a Lippmann volume hologram is formed on the photopolymer layer, and the beam from the scanning means is transmitted to the user's eye. It is made to be diffracted and focused on the pupil. The photopolymer layer may be formed with multiple holograms reflecting red, green, and blue light from each light source, or three layers of holograms corresponding to each color light may be laminated. Good. In addition, by using the wavelength selectivity of the hologram, only light of the light source wavelength is diffracted, and light of wavelengths other than the light source wavelength that occupies most of the light from the outside world is not affected by diffraction, It can be a transmissive display.

  The deflection means is not limited to deflection by a diffraction element such as a hologram, and may be a mirror such as a concave mirror or a lens such as a convex lens. In this case, it is easier to manufacture the deflection means than when a hologram is used as the deflection means.

  The control means 105 and 111 include an integrated circuit that controls each part of the HMD. The outputs of the lasers and the operations of the wavefront shape changing means and the scanning means are performed by the control means 105 and 111.

  The control means 105 and 108 include means for determining the contents to be displayed to the user.

  The control unit may include a communication unit that wirelessly connects to a peripheral device such as a mobile phone and receives a video / audio signal. Further, the control means 105, 111 may be provided with a memory storing an image to be presented to the user, or an image to be presented to the user may be acquired from an external device wirelessly.

  The control means 105 and 111 may be one, and the control means 105 or 111 may control the operations of the laser light source, the wavefront shape changing means, the scanning means, and the headphones corresponding to the left and right eyes. In this case, since only one control means is required, the cost can be reduced and the display device can be reduced in weight.

  The headphone units 106 and 112 include speakers and output sound.

  The headphone unit may include a battery that supplies power to each unit of the HMD.

  In addition, each means and each part in FIG. 1 may be incorporated in one HMD, or may not be incorporated. For example, all the components in FIG. 1 may be included in one HMD, or the headphone unit may not be provided. Moreover, each part may be distributed. For example, the control means may be partly included in the scanning means and the wavefront shape means. 1 may be shared by a plurality of devices. For example, the laser light source may be shared by two HMDs.

  Below, the scanning means in this Embodiment is explained in full detail. FIG. 4 is a sectional view of the scanning means 103 and 108 in this embodiment, and FIG. 5 is a bird's eye view. In the following description, only the scanning unit 103 will be described, but the scanning unit 108 has the same structure as that of the scanning unit 103.

  As shown in FIG. 4, the scanning unit 103 includes a hologram layer on the flat mirror 401. The hologram layer is a transmission hologram and is composed of two parts, a central part 402 and a peripheral part 403. The laser light incident on the scanning unit 103 once passes through the hologram layer, is reflected by the flat mirror 401, passes through the hologram layer again, and is emitted to the deflecting unit. This is shown in FIG.

  The scanning unit 103 changes the beam diameter of the emitted light 701 according to the position where the emitted light 701 enters the deflecting unit 104. In this embodiment, the beam diameter of the emitted light 701 is reduced when going to the farthest incident point 302 shown in FIG. 3, and the beam diameter of the emitted light 701 is increased when going to the nearest incident point 303, so that the user's eyes. Increase the resolution of the image displayed on the screen. In order to realize such adjustment of the beam diameter, the present embodiment uses the angle selectivity of the hologram. The angle selectivity of a hologram is a property that can increase the transmittance and reflectance of light incident from a specific angle, and this property is used in the peripheral portion 403.

  The incident angle of the laser beam 304 to the scanning unit when the laser beam is incident on the nearest incident point 303 is α, and the incident angle of the laser beam 305 to the scanning unit when the laser beam is incident on the farthest incident point 302 is β. And At this time, the peripheral portion 403 is designed to have the transmittance shown in FIG. As shown in this figure, light incident on the peripheral portion 403 at an angle close to the incident angle α is transmitted through the peripheral portion 403, but light incident on the peripheral portion 403 from an angle different from the incident angle α is not transmitted.

  As a specific example of creating the hologram having the transmittance shown in FIG. 6, there is a method of performing multiple exposure on the hologram having the diffraction efficiency shown in FIGS.

  FIGS. 15 and 16 are holograms designed so that the diffraction efficiency is maximized with respect to the incident angle α. The hologram having the optical performance shown in FIGS. The peripheral portion 403 has the diffraction efficiency shown in FIG. Since the diffraction efficiency and the transmittance have an inverse relationship, the hologram having the diffraction efficiency of FIG. 17 can have the transmittance shown in FIG.

  At the same time, the central portion 401 is designed to maintain the same transmittance for light from any angle. By providing the center part 402 and the peripheral part 403 having the angle selectivity described above on the flat mirror 401, the diameter of the incident beam to the deflecting means can be changed. Examples of this are shown in FIGS.

  FIG. 7 is a diagram when laser light is incident on the most recent incident point 303. At this time, the laser beam 304 is incident on the scanning means at an incident angle α. Therefore, as shown in FIG. 6, the peripheral portion 403 has a high transmittance with respect to the laser beam 304, and as a result, all of the laser beam incident on the scanning unit reaches the flat mirror 401 and is emitted toward the deflecting unit as it is. The

  FIG. 8 is a diagram when laser light is incident on the farthest incident point 302. At this time, the laser beam 304 is incident on the scanning means at an incident angle β. Therefore, as shown in FIG. 6, the peripheral portion 403 has a low transmittance with respect to the laser light 304, and as a result, part of the laser light incident on the scanning unit cannot pass through the peripheral portion 403. Therefore, only the part of the laser beam 305 that passes through the central portion 402 reaches the flat mirror 401 and is emitted as it is toward the deflecting means, and as a result, the beam diameter of the emitted light 701 is reduced.

  Thus, by providing the hologram having angle selectivity on the scanning means, the beam diameter of the laser beam toward the farthest incident point 302 can be kept small while keeping the beam diameter of the laser beam toward the nearest incident point 303 large. The resolution can be improved at any point on the screen.

  In addition, although the shape of the scanning means has been described as a rectangle, a circular mirror may be used as shown in FIG. In this case, the mirror can be made lighter than using a rectangular mirror.

  Note that the width of the peripheral portion 403 does not need to be uniform. For example, the width may be narrowed at the top and bottom of the flat mirror, and may be wide at the left and right. In this case, the beam diameter incident on the deflecting means can be changed independently in the vertical direction and the horizontal direction.

  The scanning unit may have a shape in which the central portion 402 is removed. In this case, since the amount of necessary holograms is reduced, the scanning means can be reduced in weight.

  The cross-sectional shape of the peripheral portion 403 is not a rectangle as shown in FIG. 7, but may be a triangle shape or a trapezoid shape. FIG. 10 shows an example in which the peripheral cross-sectional shape is triangular. In this case, the amount of required hologram material can be reduced. Further, since the portion that prevents the incident light 304 from entering the flat mirror 401 is reduced, the diameter of the laser light toward the farthest incident point 302 can be increased.

  Note that the scanning unit 103 does not have to scan one mirror in the biaxial direction, but may use a method of scanning laser light two-dimensionally by using two mirrors operating in the uniaxial direction. The horizontal scanning mirror at this time is shown in FIG. 11, and the vertical scanning mirror is shown in FIG. In this example, the beam diameter in the horizontal direction is adjusted by the mirror in FIG. 11, and then the emitted beam is further incident on the mirror in the vertical direction in FIG. 12 to adjust the beam diameter in the vertical direction. In this case, since it is not necessary to operate the scanning means biaxially, there is an effect that the control of each mirror is simplified.

  The scanning unit 103 may use a method of directly reflecting incident light with a hologram on the flat mirror 401 instead of the flat mirror 401. At this time, the diffraction efficiency shown in FIG. At this time, the central portion 401 is provided with optical performance equivalent to that of a mirror so as to reflect light from all incident angles.

(Embodiment 2)
In the present embodiment, a method for improving the resolution by changing the beam diameter when realizing a HUD (Head Up Display) mounted on a vehicle or an aircraft with a beam scanning display device will be exemplified.

  FIG. 13 is a side view of a laser scanning type HUD (head-up display) according to Embodiment 2 of the present invention, and FIG. 14 is a bird's-eye view.

  A laser scanning unit 1302 is embedded inside the car 1301. The laser scanning unit 1302 is attached below the windshield 1303 of the car, and is disposed inside the instrument panel in the present embodiment to save space in the display device.

  The laser scanning unit 1302 may be arranged outside the instrument panel instead of inside the instrument panel. In this case, it is easy to replace the laser scanning unit 1302 and change the position.

  The light scanned by the laser scanning unit 1302 is reflected by the deflecting means 104 attached to the windshield 1303, passes through the half mirror 1304, reaches the eyeball 1306 of the driver 1305, and an image is visually recognized. In such a HUD, it is possible to see the map information and warning information displayed by the laser scanning unit 1302 while confirming the external scenery through the windshield 1303, and it is possible to improve the safety and convenience of the driver. Become. The reflected light of the laser projected on the user's retina is reflected by the half mirror 1304 installed in front of the user's eyes and detected by the light detection means 214.

  In this embodiment mode, the laser scanning unit 1302 includes a light source 101, a wavefront shape changing unit 102, a scanning unit 103, and a control circuit 105. As shown in FIG. 14, the laser scanning unit 1302 is installed not on the user's front side but on the side mirror side, and projects laser light obliquely onto the windshield 1303. By adopting such a configuration, it is possible to increase the degree of freedom of the location where the laser scanning unit 1303 is arranged, and there is an effect of improving the design of the vehicle.

  The deflecting means 104 may be freely attached to and detached from the windshield 1303. In this case, when the display on the display is unnecessary, the changing means 104 is removed, so that the transparency of the windshield 1303 can be maintained and the safety of the driver can be improved.

  The deflecting unit 104 may reflect the light from the scanning unit not toward one of the eyes of the user but to the eyes of the user. In this case, the video can be displayed on both eyes of the user by one change means 104.

  In the embodiment of the present invention, a half mirror 1304 is installed in front of the user's eyes so that the reflected light from the user's retina is reflected to the light detection unit 214. The half mirror 1304 is attached to the car ceiling 1307 by a support bar 1308, and this structure detects the spot size on the user's retina without forcing the device to be mounted on the user's head. Can do. The half mirror 1304 and the light detector 214 may be installed not on the ceiling of the car but on the driver's glasses or hat. In this case, even if the driver's head moves back and forth, the possibility that the head contacts the half mirror is reduced, so that the driver's safety can be improved.

  The control means 105 includes an integrated circuit that controls each part of the HUD. The output of each laser and the operations of the wavefront shape changing means, the scanning means, and the photodetector are performed by the control means 105. The control means 105 also includes a function for controlling the operation of the wavefront shape changing means. In this embodiment, the light detection means 214 is arranged on the ceiling and the control circuit 105 is installed inside the instrument panel. However, the communication between the light detection means 214 and the control circuit 105 has a wired cable inside the car. May be performed by wireless communication.

  In the present embodiment, as shown in FIG. 14, laser light is projected obliquely onto the windshield 1303, so that the laser light directed to the user's eyeball 1306 is made parallel light as in the first embodiment. Countermeasures are required. Therefore, also in the present embodiment, the scanning means 103 is composed of a flat mirror and a hologram layer, as in the first embodiment, and has the structure shown in FIGS.

  By providing the peripheral portion 403 with the angle selectivity shown in FIG. 6, the beam diameter of the laser light toward the nearest incident point in FIG. 14 is increased, and the beam diameter of the laser light toward the farthest incident point 302 is increased. It becomes possible to make it small, and it becomes possible to improve the resolution of the whole image.

  In FIG. 14, the laser light is incident only on one eye of the user, but another set of laser scanning unit 1302, changing means 104, and light detecting means 214 is prepared, and laser light is incident on both eyes. Also good. In this case, an image can be displayed for both eyes, and an image with a wide viewing angle or a three-dimensional image can be presented.

  The control processing in each embodiment described above is performed by the CPU interpreting and executing predetermined program data stored in a storage device (ROM, RAM, hard disk, etc.) that can execute the processing procedure described above. Realized. In this case, the program data may be introduced into the storage device via the recording medium, or may be directly executed from the recording medium. The recording medium refers to a recording medium such as a semiconductor memory such as a ROM, a RAM, or a flash memory, a magnetic disk memory such as a flexible disk or a hard disk, an optical disk such as a CD-ROM, DVD, or BD, or a memory card such as an SD card. . The recording medium is a concept including a communication medium such as a telephone line or a conveyance path.

  The beam scanning display device according to the present invention includes a beam cross-section changing unit and the like, and can be applied to uses such as a display device, a display system, a display method, and a display program.

1 is a configuration diagram of a beam scanning display device according to a first embodiment of the present invention. 1 is a detailed configuration diagram of a beam scanning display device according to Embodiment 1 of the present invention. The figure which shows the example of the beam waist position of the incident laser for making incident light to an eyeball into parallel light Sectional drawing of the scanning means in Embodiment 1 of this invention Bird's-eye view of scanning means in Embodiment 1 of the present invention The figure which shows the example of the transmittance | permeability which the hologram layer periphery part of the scanning means has in Embodiment 1 of this invention The figure which shows reflection on the scanning means of the laser beam which injects into the most recent incident point The figure which shows reflection on the scanning means of the laser beam which injects into the farthest incident point Bird's-eye view of scanning means in Embodiment 1 of the present invention Sectional drawing of the scanning means in Embodiment 1 of this invention The bird's-eye view of the horizontal direction scanning means in Embodiment 1 of this invention Bird's-eye view of vertical scanning means in Embodiment 1 of the present invention Configuration diagram of a beam scanning display device in a second embodiment of the present invention Bird's-eye view of the beam scanning display device in the second embodiment of the present invention The figure which shows one of the diffraction efficiencies given to the peripheral part in Embodiment 1 of this invention The figure which shows one of the diffraction efficiencies given to the peripheral part in Embodiment 1 of this invention The figure which shows the example of the diffraction efficiency which the whole peripheral part in Embodiment 1 of this invention has The figure which shows the example of the diffraction efficiency which the whole peripheral part in Embodiment 1 of this invention has

Explanation of symbols

101 Left-eye light source 102 Left-eye wavefront shape changing means 103 Left-eye scanning means 104 Left-eye deflection means 105 Left-eye control means 106 Left-eye headphone unit 110 Right-eye light source 109 Right-eye wavefront shape changing means 108 right-eye scanning means 107 right-eye deflection means 111 right-eye control means 112 right-eye headphone unit 201 focal length horizontal component changing means 202 focal length vertical component changing means 211 red laser light source 212 blue laser light source 213 green laser light source 214 Photodetection means

Claims (8)

A light source that outputs a beam;
Wavefront shape changing means for changing the wavefront shape of the beam from the light source;
Scanning means for scanning the beam from the wavefront shape changing means;
Deflecting means for changing the beam scanned by the scanning means in a direction toward the user's eyes;
A beam scanning display device comprising:
The beam scanning type display device, wherein the scanning means comprises beam cross-section changing means for changing the cross-sectional shape of the incident beam. The scanning means is a mirror that scans a beam by changing an inclination angle,
2. The beam scanning display device according to claim 1, wherein the beam section changing means is a transmission hologram formed on the mirror. 3. The transmission hologram includes a central portion and a peripheral portion, and the peripheral portion has higher transmittance for incident light from a specific angle than incident light from other angles. Beam scanning display device. The peripheral portion has the deflecting unit when the beam having a beam waist position at a position close to the deflecting unit is incident on the deflecting unit with respect to an incident angle at which the beam is incident on the scanning unit. 4. A beam scanning type display device according to claim 3, wherein a beam having a beam waist position at a position far from the light beam has a higher transmittance than the incident angle at which the beam enters the scanning means. 5. The beam scanning display apparatus according to claim 4, wherein the peripheral portion has a width different between a portion perpendicular to the horizontal scanning direction of the scanning means and a portion perpendicular to the vertical scanning direction of the scanning means. 6. The beam scanning display device according to claim 5, wherein the peripheral portion has a trapezoidal cross-sectional shape. 3. The beam scanning display according to claim 2, wherein the transmission hologram includes only a peripheral portion having a hole in a central portion, and the peripheral portion has a high transmittance with respect to an incident angle from a specific angle. apparatus. A beam output step for outputting a beam;
A wavefront shape step for changing a wavefront shape of the beam by the beam output step;
A scanning step of scanning the beam from the wavefront shape changing means step;
A deflection step of changing the beam scanned in the scanning step in a direction toward the user's eye;
A beam scanning display method comprising:
The beam scanning display method, wherein the scanning step includes a beam cross-section changing step for changing a cross-sectional shape of an incident beam.

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