Pupil or cornea position detection device and head mount display

Abstract

To detect a position of a pupil or a cornea of a wearer without inhibiting the visibility of the wearer with respect to the outside world.SOLUTION: A pupil or cornea position detection device is a position detection device of a pupil or a cornea of a wearer of a head mount display attachable to the head mount display. The device comprises: a light source part; a light receiving part which receives at least a part of light emitted from the light source part and reflected by an eyeball of the wearer; a connection part connected to the head mount display; and a support part for supporting the light source part and the light receiving part integrally. The connection part is connected to the head mount display in an upper direction crossing a looking-straight direction of the wearer, of the light source part and the light receiving part supported by the support part.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a pupil or cornea position detection device and a head-mounted display. [Background technology]

[0002] For example, Patent Document 1 discloses a device that detects the pupil position based on the time change in the intensity of reflected light of a laser beam that is scanned at high speed on the surface of the eyeball. Summary of the Invention [Problem to be solved by the invention]

[0003] However, when the device described in Patent Document 1 is attached to a head-mounted display, the field of view of the outside world of the person wearing the head-mounted display may be obstructed by a part of the device, thereby narrowing the field of view. [Means for solving the problem]

[0004] A pupil or corneal position detection device according to one embodiment of the present invention is a pupil or corneal position detection device that can be attached to a head-mounted display and detects the position of the pupil or cornea of ​​a wearer of the head-mounted display, and includes a light source unit, a light receiving unit that receives at least a portion of the light emitted from the light source unit and reflected by the wearer's eyeball, a connection unit that connects to the head-mounted display, and a support unit that supports the light source unit and the light receiving unit together, and the connection unit connects to the head-mounted display in an upward direction that intersects with the wearer's direct viewing direction of the light source unit and the light receiving unit supported by the support unit. [Effects of the Invention]

[0005] According to the present invention, the position of the pupil or cornea of ​​the wearer can be detected without obstructing the wearer's view of the outside world. [Brief explanation of the drawings]

[0006] [Figure 1] 1 is a schematic perspective view showing a head-mounted display having a pupil or cornea position detection device according to a first embodiment of the present invention. [Figure 2] 1 is a schematic perspective view showing a state in which a head-mounted display having a pupil or cornea position detection device according to a first embodiment of the present invention is worn on the head of a wearer. [Figure 3] 1 is a schematic top view showing the overall configuration of a pupil or cornea position detection device according to a first embodiment of the present invention; [Figure 4] 1 is a first schematic perspective view showing the overall configuration of a pupil or cornea position detection device according to a first embodiment of the present invention. [Figure 5] FIG. 2 is a second schematic perspective view showing the overall configuration of the pupil or cornea position detection device according to the first embodiment of the present invention. [Figure 6] 1 is a schematic front view showing the widths in the vertical direction of an eyeball, a light source unit, and a light receiving unit in a pupil or cornea position detection device according to a first embodiment of the present invention. FIG. [Figure 7] 1A and 1B are first schematic top views illustrating the operation of the pupil or cornea position detection device according to the first embodiment of the present invention. [Figure 8] FIG. 4 is a second schematic top view showing the operation of the pupil or cornea position detection device according to the first embodiment of the present invention. [Figure 9] FIG. 10 is a schematic perspective view showing an adjustment mechanism in a pupil or cornea position detection device according to a second embodiment of the present invention. [Figure 10] FIG. 10 is a schematic perspective view showing an elastic member in a pupil or cornea position detection device according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0007] A pupil or cornea position detection device and a head-mounted display according to an embodiment of the present invention will be described in detail with reference to the drawings. However, the following embodiments are merely examples of the pupil or cornea position detection device and the head-mounted display according to the embodiment of the present invention, and are not limited to the following.

[0008] Furthermore, unless otherwise specified, the dimensions, materials, shapes, relative arrangements, etc. of components described in the embodiments of the present invention are merely illustrative examples and are not intended to limit the scope of the embodiments of the present invention to those specific embodiments. The sizes, positional relationships, etc. of components shown in the drawings may be exaggerated for clarity. In the following description, the same names and symbols indicate the same or similar components, and detailed descriptions will be omitted where appropriate.

[0009] In the following description, for ease of understanding, the arrangement and configuration of each part will be described using an XYZ Cartesian coordinate system. The three axes in the XYZ Cartesian coordinate system are mutually orthogonal. In the XYZ Cartesian coordinate system, the direction in which the X axis extends is referred to as the first direction X, the direction in which the Y axis extends is referred to as the second direction Y, and the direction in which the Z axis extends is referred to as the third direction Z. The direction in which the arrow indicating the X axis points is referred to as the +X direction or +X side, and the direction opposite to the +X direction is referred to as the -X direction or -X side. The direction in which the arrow indicating the Y axis points is referred to as the +Y direction or +Y side, and the direction opposite to the +Y direction is referred to as the -Y direction or +Y side. The direction in which the arrow indicating the Z axis points is referred to as the +Z direction or +Z side, and the direction opposite to the +Z direction is referred to as the -Z direction or -Z side. In this specification, as an example, the Y direction corresponds to the up-down direction, and the +Y direction corresponds to the upward direction. The +Z direction corresponds to the normal viewing direction. The normal viewing direction is the direction of the wearer's line of sight when looking straight ahead. The X direction corresponds to the left-right direction.

[0010] However, the above directional expressions merely describe the relationship of relative position, orientation, direction, etc., and do not necessarily correspond to the relationship during use. Furthermore, these directions are unrelated to the direction of gravity. "Placing" is not limited to direct contact, but also includes indirect placement, for example, via another member. "Image" in this specification includes not only still images but also moving images. Moving images may also be called video.

[0011] [First embodiment] <Configuration of pupil or cornea position detection device according to the first embodiment of the present invention> The configuration of a pupil or cornea position detection device according to a first embodiment of the present invention will be described with reference to FIGS. 1 to 6. FIG. 1 is a schematic perspective view showing a head mounted display (HMD) 200 having a pupil or cornea position detection device 100 according to the first embodiment of the present invention. FIG. 2 is a schematic perspective view showing a state in which the head mounted display 200 having the pupil or cornea position detection device 100 according to the first embodiment of the present invention is worn on the head 300H of a wearer 300. FIG. 3 is a schematic top view showing the overall configuration of the pupil or cornea position detection device 100 according to the first embodiment of the present invention. FIG. 4 is a first schematic perspective view of the pupil or cornea position detection device 100 according to the first embodiment of the present invention, viewed from the +X side. FIG. 5 is a second schematic perspective view of the pupil or cornea position detection device 100 according to the first embodiment of the present invention, viewed from the +Y side. FIG. 6 is a schematic front view showing the widths in the vertical direction (hereinafter referred to as the Y direction) of the eyeball 50, the light source unit 1, and the light receiving unit 2 in the pupil or cornea position detection device 100 according to the first embodiment of the present invention.

[0012] The pupil or cornea position detection device 100 is a device that can be attached to the head mounted display 200 and detects the position of the pupil or cornea of ​​the wearer 300 of the head mounted display 200. The pupil or cornea position detection device 100 detects the position of either the pupil or the cornea of ​​the wearer 300. For ease of explanation, the pupil or cornea will hereinafter be referred to as the pupil P. Furthermore, the pupil or cornea position detection device 100 will be simply referred to as the position detection device 100.

[0013] As shown in FIGS. 1 and 2, the head-mounted display 200 includes a position detection device 100. In the example shown in FIGS. 1 and 2, the head-mounted display 200 includes a mounting unit 201 for a wearer 300, display units 202 that are disposed in front of the right and left eyes of the wearer 300 and display images, respectively, and a holder 203 that is connected to the mounting unit 201 and holds the display unit 202. The display unit 202 includes a right-eye display unit 202a that displays an image to be observed by the right eye of the wearer 300, and a left-eye display unit 202b that displays an image to be observed by the left eye of the wearer 300. The position detection device 100 is disposed near the left-eye display unit 202b, or from another perspective, near the left eye of the wearer 300. The position detection device 100 is fixed to a lower surface 203a (the surface on the -Y side) of the holder 203 with a screw member, an adhesive member, or the like.

[0014] The head mounted display 200 is a headgear type head mounted display that is worn on the head 300H of the wearer 300 via a wearing part 201 made of a soft material such as nylon. However, the head mounted display 200 is not limited to the headgear type, and may be in various forms other than the headgear type, such as glasses type, hat type, or helmet type.

[0015] The head mounted display 200 is a display device that is worn by the wearer 300 and displays an image observed by the wearer 300. The image display method by the head mounted display 200 may be, for example, a method in which a real or virtual image of an image displayed by a display element such as a liquid crystal or a DMD (Digital Micromirror Device) is observed by the wearer 300 via an optical system, or a method in which an image is directly drawn on the retina of the wearer 300. The image display method by the head mounted display 200 is a so-called see-through method in which an image is displayed superimposed on the field of view of the wearer 300 with respect to the outside world.

[0016] As shown in FIG. 3 , the position detection device 100 includes a light source unit 1, a light receiving unit 2 that receives at least a portion of light Lo emitted from the light source unit 1 and reflected by the eyeball 50 of the wearer 300, a connection unit 3 that connects to the head-mounted display 200, and a support unit 4 that integrally supports the light source unit 1 and the light receiving unit 2. In the example shown in FIG. 3 , the position detection device 100 includes an optical deflection unit 5 that is disposed in an optical path between the light source unit 1 and the eyeball 50 when the position detection device 100 is worn by the wearer 300 and deflects light Li1 emitted from the light source unit 1 in the direction of the eyeball 50. Furthermore, the position detection device 100 includes a first mounting substrate 11 on which the light source unit 1 is mounted and a second mounting substrate 21 on which the light receiving unit 2 is mounted. The light source unit 1 is supported by the support unit 4 via the first mounting substrate 11. The light receiving unit 2 is supported by the support unit 4 via the second mounting substrate 21. The support part 4 is located below the eyeball 50 (hereinafter referred to as the -Y direction) and includes an extension part 41 that extends in the left-right direction (hereinafter referred to as the X direction) that intersects with both the Y direction and the normal viewing direction N.

[0017] In FIG. 3, a portion of light Li1 emitted from the light source unit 1 and incident on the light deflection unit 5 is indicated by a dashed-dotted arrow. Furthermore, a portion of light Li2 reflected by the light deflection unit 5 and incident on the eyeball 50 is indicated by a two-dot chain arrow. Furthermore, a portion of light Lo reflected by the eyeball 50 is indicated by a dashed arrow. The paths taken by light Li1 and light Li2 correspond to the optical path between the light source unit 1 and the eyeball 50 when the position detection device 100 is worn by the wearer 300. In FIG. 3, the eyeball 50 and the wearer 300 are both indicated with the symbols for the purpose of indicating that the wearer 300 has the eyeball 50. In the drawings shown later, the symbols may also be used for the same purpose.

[0018] The position detection device 100 detects the position of the pupil P of the left eye of the wearer 300 and passes information regarding the position of the pupil P of the left eye to the head mounted display 200. The head mounted display 200 controls the display positions of images on the right eye display unit 202a and the left eye display unit 202b, respectively, based on the information regarding the position of the pupil P of the wearer 300 received from the position detection device 100. The head mounted display 200 can display high-quality images with reduced distortion, blur, vignetting, etc. by controlling the display positions according to the tilt or line of sight of the eyeball 50 of the wearer 300. Note that in the example shown in FIG. 2, the head mounted display 200 controls the display positions of images on the right eye display unit 202a and the left eye display unit 202b, respectively, based on the detection result of the pupil P of the left eye, under the assumption that the right eye and left eye of the wearer 300 move in approximately the same way.

[0019] Here, when a pupil or cornea position detection device is attached to a head-mounted display, the field of view of the outside world of the person wearing the head-mounted display may be obstructed by part of the pupil or cornea position detection device, thereby narrowing the field of view.

[0020] For example, suppose a support unit provided in a pupil or cornea position detection device includes an opening, and the wearer observes the outside world through the opening. The shape of the face, head, or eyeballs of the head-mounted display wearer varies from person to person. Specifically, there are individual differences in the interocular distance, the distance between the medial canthus, the distance from the forehead to the eyes, and the like. Due to the influence of these individual differences, when the pupil or cornea position detection device is attached to the head-mounted display, the relative position between the opening in the support unit and the wearer's face may be shifted. If the position of the opening is shifted from the appropriate position, the frame of the opening will obstruct the wearer's field of vision, narrowing the wearer's field of view of the outside world.

[0021] As shown in FIGS. 4 and 5 , in the position detection device 100, the connection unit 3 is connected to the head-mounted display 200 in the +Y direction of the light source unit 1 and the light receiving unit 2 supported by the support unit 4. By connecting to the head-mounted display 200 in the +Y direction intersecting the normal viewing direction N and providing an integrated position detection device 100, interference with the head-mounted display can be prevented. This makes it possible to detect the position of the wearer's pupil or cornea without obstructing the wearer's field of vision of the outside world. Furthermore, in the position detection device 100, the light source unit 1 and the light receiving unit 2 are arranged in line with the eyeball 50 in the X direction when viewed from the normal viewing direction N. As a result, the support unit 4 is not located in the +Y direction of the eyeball 50. As a result, the support unit 4 does not obstruct the field of vision of the wearer 300, thereby widening the field of vision of the outside world of the wearer 300.

[0022] The state in which "the support unit 4 does not obstruct the field of view of the wearer 300" is a state in which the support unit 4 does not overlap the eyeball 50 when viewed from the normal viewing direction N of the wearer 300. In other words, the state in which "the support unit 4 does not obstruct the field of view of the wearer 300" is a state in which the support unit 4 is not positioned between the eyeball 50 of the wearer 300 and the image displayed on the display unit 202 in the Z direction along the Z axis. "The light source unit 1 and the light receiving unit 2 are arranged side by side with the eyeball 50 in the X direction when viewed from the normal viewing direction N" means that, as shown in FIG. 6, when viewed from the normal viewing direction N (the +Z direction in the case of FIG. 6), the light source unit 1 and the light receiving unit 2 are aligned with the eyeball 50 in the X direction in a state in which the first width W1 in the Y direction of the light source unit 1 and the second width W2 in the Y direction of the light receiving unit 2 each fall within the range of the third width W3 in the Y direction of the eyeball 50. The third width W3 may be replaced with "the width of the image displayed on the display unit 202." Furthermore, "the connection unit 3 is connected to the head mounted display 200 in the +Y direction of the light source unit 1 and the light receiving unit 2" means that the connection unit 3 is connected to the head mounted display 200 at least at a position where the upper end 3a of the connection unit 3 is higher (on the +Y side) than the upper end 50a of the eyeball 50 in FIG.

[0023] In the position detection device 100, the light Li2 emitted from the light source unit 1 is deflected by the optical deflection unit 5, and the light Li2 deflected by the optical deflection unit 5 is made incident on the eyeball 50. The light receiving unit 2 receives at least a part of the light Lo that has been deflected by the optical deflection unit 5 and then reflected by the eyeball 50.

[0024] For example, in a configuration in which light Li1 emitted from the light source unit 1 is directly incident on the eyeball 50, the light receiving unit 2 needs to be placed on the opposite side of the eyeball 50 from the light source unit 1 in order for the light receiving unit 2 to receive light Lo reflected by the eyeball 50. If the light receiving unit 2 is placed on the opposite side of the eyeball 50 from the light source unit 1 in the X direction along the X axis (for example, the position where the light deflection unit 5 is placed in FIG. 5), the configuration of the position detection device becomes complicated, and the wiring for driving the light source unit 1 and the light receiving unit 2 also becomes complicated.

[0025] In the position detection device 100, the light Li2 deflected by the optical deflection unit 5 is incident on the eyeball 50, and therefore the light receiving unit 2 can be arranged on the same side as the light source unit 1 with respect to the eyeball 50 in the X direction along the X axis. This simplifies the configuration of the position detection device 100 and the wiring for driving each of the light source unit 1 and the light receiving unit 2. However, the position detection device 100 does not necessarily have to include the optical deflection unit 5, and the light receiving unit 2 may be arranged on the opposite side of the eyeball 50 from the light source unit 1.

[0026] In the position detection device 100, the support unit 4 includes an extension unit 41 and supports the light deflection unit 5 at a position opposite the light source unit 1 in the X direction relative to the eyeball 50. In the example shown in FIG. 3 , the light source unit 1 is located on the left side (−X side) of the eyeball 50, and the support unit 4 supports the light deflection unit 5 on the right side (+X side) of the eyeball 50. Because the extension unit 41 is located in the −Y direction of the eyeball 50, it does not obstruct the field of view of the wearer 300. This widens the field of view of the wearer 300 with respect to the outside world. Note that "the extension unit 41 is located in the −Y direction of the eyeball 50" means that, in FIG. 6 , at least the upper end 41 a of the extension unit 41 is located on the −Y side of the lower end 50 b of the eyeball 50. The lower end 50 b of the eyeball 50 may be replaced with the lower end of the image displayed on the display unit 202.

[0027] In the position detection device 100, the connection portion 3, the support portion 4, and the extension portion 41 are integrally formed. This prevents deviation in the relative positions of the connection portion 3, the support portion 4, and the extension portion 41, thereby reducing deviation in the relative positions of the head mounted display 200 and the light source portion 1, the light receiving portion 2, and the light deflection portion 5, thereby reducing deviation in the relative positions of the light source portion 1, the light receiving portion 2, and the light deflection portion 5. The position detection device 100 can detect the pupil P of the wearer 300 with high accuracy. The head mounted display 200 can display high-quality images.

[0028] In the position detection device 100, the support unit 4 includes a first flat surface 12 that is disposed at a first angle θ1 with respect to a reference plane 410 of the extension unit 41 in a top view and supports the light source unit 1, and a second flat surface 22 that is disposed at a second angle θ2, different from the first angle θ1, with respect to the reference plane 410 of the extension unit 41 and supports the light receiving unit 2. With this configuration, the support unit 4 can support the light source unit 1 and the light receiving unit 2 using the first flat surface 12 and the second flat surface 22 that are disposed at different angles with respect to the reference plane 410. The position detection device 100 can deflect light Li1 emitted from the light source unit 1 via the extension unit 41 by the light deflection unit 5 supported by the support unit 4, and irradiate the eyeball 50 with light Li2. The position detection device 100 can also receive light Lo reflected by the eyeball 50 by the light receiving unit 2.

[0029] 1 and 2, in the head mounted display 200, the connection unit 3 of the position detection device 100 is connected to the lower surface 203a of the holding unit 203. This prevents the head mounted display 200 or the support unit 4 from being positioned in the +Y direction of the eyeball 50. As a result, the support unit 4 does not block the field of view of the wearer 300, thereby widening the field of view of the outside world of the wearer 300.

[0030] As shown in FIG. 2, when the head-mounted display 200 is worn by the wearer 300, the position detection device 100 is disposed on the opposite side of the display unit 202 with respect to the left eye of the wearer 300. The opposite side of the display unit 202 with respect to the left eye of the wearer 300 is, in other words, the opposite side of the nose 300N of the wearer 300. This arrangement reduces the obstruction of the wearer's 300's field of vision by the support unit 4 of the position detection device 100, thereby widening the wearer's 300's field of vision to the outside world, compared to when the position detection device 100 is disposed on the same side of the wearer's 300 with respect to the left eye of the wearer 300. In the example shown in FIG. 2, the left eye of the wearer 300 is located on the −Z side of the left-eye display unit 202b. The display unit 202 of the wearer 300, the left eye of the wearer 300, and the position detection device 100 are aligned in the first direction X. The display unit 202 is located on the +X side of the left eye of the wearer 300. The position detection device 100 is located on the −X side of the left eye of the wearer 300.

[0031] The head mounted display 200 may also include a position detection device for the pupil P of the right eye of the wearer 300 and a position detection device for the pupil P of the left eye of the wearer 300. The position detection device for the pupil P of the right eye is arranged on the opposite side of the display unit 202 with respect to the right eye of the wearer 300 when the head mounted display 200 is worn by the wearer 300. The position detection device for the pupil P of the left eye is arranged on the opposite side of the display unit 202 with respect to the left eye of the wearer 300. With this configuration, the position detection device 100 can control the display position of an image by the right eye display unit 202a based on information about the position of the pupil P of the right eye of the wearer 300. Furthermore, the position detection device 100 can control the display position of an image by the left eye display unit 202b based on information about the position of the pupil P of the left eye of the wearer 300. As a result, the head mounted display 200 can display a high quality image whose display position is controlled with high precision according to the inclination of the eyeballs of the wearer 300, the line of sight direction, or the like.

[0032] Each component of the position detection device 100 will be described in detail below.

[0033] (Light source part 1) The light source unit 1 includes, for example, a VCSEL (Vertical Cavity Surface Emitting Laser). The VCSEL has a plurality of light-emitting units arranged two-dimensionally within a plane. Each light-emitting unit emits laser light having directivity and a finite spread angle. The emission and non-emission of laser light from each light-emitting unit is individually controlled. The light source unit 1 is mounted on a mounting board and placed on a support unit 4.

[0034] The light source unit 1 is not limited to a VCSEL. The light source unit 1 may use a plurality of LDs (semiconductor lasers: laser diodes) or LEDs (light emitting diodes: light emitting diodes) that emit laser beams arranged two-dimensionally in a plane. The light source unit 1 may also use a pulsed laser that emits pulsed laser beams. Furthermore, the light source unit 1 may use a combination of a plurality of types of light sources.

[0035] The light emitted from the light source unit 1 is preferably invisible light such as near-infrared light so as not to obstruct the field of vision of the wearer 300. However, the light emitted from the light source unit 1 is not limited to invisible light and may be visible light.

[0036] (Light receiving part 2) The light receiving unit 2 includes, for example, a PSD (Position Sensitive Detector). The PSD is a two-dimensional light position sensitive detector that detects a current value corresponding to the distance of incident light to an electrode in two orthogonal directions within the light receiving surface, and calculates and outputs a detection signal indicating the position of the incident light from the ratio of the current values ​​in the two orthogonal directions. The PSD outputs a detection signal indicating the position of a light spot formed on the light receiving surface of the PSD.

[0037] A PSD has four output terminals. A PSD has a resistive film arranged on a continuous light-receiving surface (a light-receiving surface not divided into pixels), and electrode pairs arranged in two orthogonal directions. The photocurrent generated at the light spot position is divided into four parts according to the distance to each output terminal. At this time, the electrical resistance of the resistive film acts so that the current decreases as the distance between the light spot position and the output terminal increases. The PSD detects the electrical signal that passes through the resistive film via the four terminals and outputs a detection signal that indicates the position within the light-receiving surface, obtained through electrical post-processing. The PSD can convert the current generated by photoelectric conversion into an analog voltage signal and output it as a detection signal from the four terminals. In other words, a PSD can detect the position of incidence by using the surface resistance to determine the distance from each terminal.

[0038] The light receiving unit 2 may include an image sensor (image pickup element) instead of a PSD as a position detection means. However, the output result of the image sensor varies depending on the intensity of light incident on each pixel, and low intensity results in low output current. To reduce the effects of noise light such as sunlight, it is necessary to increase the output of the light source to increase the intensity of light incident on the image sensor. Furthermore, in the case of an image sensor, image processing is required for position detection. Therefore, from the perspective of safety for the eyeball 50 and reducing the processing load, it is preferable that the light receiving unit 2 include a PSD as a position detection means.

[0039] By using a PSD as the light receiving unit 2, the position is detected using the current division ratio (proportion) divided between the output terminals, so the position of the incident light can be detected regardless of the intensity of the incident light. This increases safety for the eye 50. Furthermore, since image processing is not required, processing is simplified and the processing load is reduced. However, the light receiving unit 2 is not limited to a PSD and may have other configurations. Furthermore, the PSD is not limited to a two-dimensional PSD that detects two-dimensional positions within the light receiving surface, but may be a one-dimensional PSD that detects one-dimensional positions within the light receiving surface. The light receiving unit 2 is mounted on a mounting board and placed on the support unit 4. The light source unit 1 and the light receiving unit 2 may be mounted on the same mounting board.

[0040] (Connection 3) The connection unit 3 is a portion that connects to the head mounted display 200. The position where the connection unit 3 connects to the head mounted display 200 can be changed as appropriate depending on the shape of the head mounted display 200, etc. The shape of the connection unit 3 can be changed as appropriate depending on the position where the connection unit 3 connects to the head mounted display 200, etc. The connection unit 3 can be made of a material that includes a resin material, a metal material, etc.

[0041] (Support part 4) The support part 4 is a part that supports the light source part 1 and the light receiving part 2. The shape of the support part 4 can be changed as appropriate depending on the positions that support the light source part 1, the light receiving part 2, and the light deflection part 5, or the shapes of these parts. The support part 4 can be made of a material that includes a resin material, a metal material, or the like.

[0042] (Light deflector 5) The light deflection unit 5 can be, for example, a concave mirror. The concave mirror is a focusing reflecting member that has a concave reflecting surface with a curvature, reflects incident light Li1, and irradiates the eyeball 50 with focused light Li2. The light Li2 is incident near the pupil of the eyeball 50. The center of curvature of the concave surface of the concave mirror is located off the optical axis of the optical path from the light source unit 1 to the light deflection unit 5. The optical system including the light source unit 1, the light receiving unit 2, and the light deflection unit 5 constitutes an off-axis optical system. An off-axis optical system is one that has a structure in which an axis of rotational symmetry exists in a space external to the optical system.

[0043] The light deflection unit 5 is not limited to a concave mirror, but may be a plane mirror, a combination of a convex lens and a plane mirror, a wavefront control element using a hologram, a diffractive optical element, etc. Furthermore, if an anamorphic aspherical surface with different curvatures in two orthogonal directions in a plane intersecting the optical axis of the focused laser light is used as the concave surface of the concave mirror, the diameter of the light beam can be further reduced and the light can be shaped into an isotropic state.

[0044] (Other components) In addition to the above components, the position detection device 100 may have a processing unit etc. The processing unit outputs a control signal to drive the VCSEL to emit light, and receives a detection signal from the light receiving unit 2 to execute processing to detect the position of the pupil P of the eyeball 50. The processing unit is disposed on the support unit 4 etc.

[0045] The position of the light Lo incident on the light receiving unit 2 changes depending on the tilt of the eyeball 50. The processing unit converts the detection signal of the light receiving unit 2 into coordinate information, thereby detecting the position of the pupil P of the eyeball 50. The light receiving unit 2 can detect the position of the reflection point on the eyeball 50 and the direction of the normal vector. The position detection device 100 can estimate the pupil position based on the correspondence between the detected positions of the reflection points, the normal vectors, and the surface shape model of the eyeball.

[0046] <Operation of the position detection device 100 according to the first embodiment of the present invention> The operation of the position detection device 100 according to the first embodiment of the present invention will be described with reference to Figures 7 and 8. Figure 7 is a first schematic top view showing the operation of the position detection device 100 according to the first embodiment of the present invention. Figure 8 is a second schematic top view showing the operation of the position detection device 100 according to the first embodiment of the present invention.

[0047] When the head-mounted display 200 connected to the position detection device 100 is worn by the wearer 300, the light source unit 1, the light receiving unit 2, and the light deflection unit 5 are positioned close to (in front of) the eyeball 50 of the wearer 300.

[0048] In the off-axis optical system of the position detection device 100, light Lo before reaching the eyeball 50 propagates through the space in front of the eye adjacent to the eyeball 50, turning back at least once, without being reflected or scattered by the eyeball 50, before reaching the eyeball 50. In the example shown in FIGS. 7 and 8 , light Li1 emitted from the light source unit 1 propagates through the space in front of the eye toward the optical deflection unit 5 in a direction substantially parallel to the face of the wearer 300 wearing the head-mounted display 200. The light Li1 is divergent light that propagates while widening the diameter of the light beam due to diffraction at the opening of the exit unit of the light source unit 1. The divergence angle of the divergent light can be controlled by the shape of the opening of the exit unit. The light Li1 propagates while diverging and enters the optical deflection unit 5.

[0049] The light deflection unit 5 reflects the incident light Li1 and irradiates the eyeball 50 with light Li2, which is a focused light. The angle of incidence of the light Li2 on the eyeball 50 is adjusted so that the light Li2 is incident at a predetermined angle on the center of the pupil of the eyeball 50 when the eye is looking straight ahead. The light source unit 1 can emit light Li1 from multiple light-emitting units. The laser light emitted from the multiple light-emitting units is irradiated onto multiple locations on the eyeball 50 or is irradiated onto the eyeball 50 at multiple angles.

[0050] The pupil surface (corneal surface) of the eyeball 50 is a transparent body containing water and generally has a reflectance of approximately 2 to 4%. Light Li1 incident on the vicinity of the pupil of the eyeball 50 is reflected by the surface of the pupil of the eyeball 50, and the reflected light Li2 propagates toward the light receiving unit 2. The curvature of the reflecting surface of the light deflection unit 5 is determined so as to offset the divergence of light Lo reflected by the curvature of the eyeball or cornea. In this way, the diameter of the beam of light Lo propagating toward the light receiving unit 2 does not widen on the light receiving surface of the light receiving unit 2.

[0051] The light source unit 1 has multiple light-emitting units and is capable of high-speed modulation. By time-modulating the laser light irradiated onto the eyeball 50 and extracting from the output signal of the light-receiving unit 2 a component having a modulation frequency that matches the laser light incident on the light-receiving unit 2, it is possible to eliminate the influence of light from the external environment that does not involve modulation. As a result, the signal-to-noise ratio can be improved, which is advantageous for pupil position detection in bright environments. It is also possible to reduce the amount of laser light irradiated onto the eyeball 50.

[0052] FIG. 7 shows a state in which the wearer 300 is looking straight ahead. The light source unit 1 emits light Li1 from one of the multiple light-emitting units. The light deflection unit 5 reflects the light Li1 toward the eyeball 50. Light Li2, which is light reflected from the light deflection unit 5 of light Li1, enters the eyeball 50. The eyeball 50 reflects the light Li2. Light Lo, which is light reflected from the eyeball 50 of light Li2, enters the light receiving unit 2. Note that in FIG. 7, a portion of each of light Li1, light Li2, and light Lo is represented by a solid arrow. This is also true in FIG. 8.

[0053] In the example shown in Figure 7, the light source unit 1 emits light Li1' from another light-emitting unit among the multiple light-emitting units. The light deflection unit 5 reflects light Li1' toward the eyeball 50. Light Li2', which is light reflected from the light deflection unit 5 of light Li1', enters the eyeball 50. The eyeball 50 reflects light Li2'. Light Lo', which is light reflected from the eyeball 50 of light Li2', does not enter the light receiving unit 2. Note that in Figure 7, parts of light Li1', light Li2', and light Lo' are represented by dashed arrows. This is also true in Figure 8.

[0054] 7, the light Lo is incident on the light receiving unit 2, and the light Lo' is not incident on the light receiving unit 2. The position detection device 100 can detect the position of the pupil P of the eyeball 50 using the light receiving signal of the light Lo received by the light receiving unit 2.

[0055] 8 shows a state in which the eyeball 50 is tilted relative to the eyeball 50 in the example of FIG. 7 as a result of the wearer 300 slightly moving his or her line of sight from the normal viewing state. Light Lo derived from light Li1 from one of the multiple light-emitting units does not enter the light-receiving unit 2. Light Lo' derived from light Li1' from another of the multiple light-emitting units enters the light-receiving unit 2. The position detection device 100 can detect the position of the pupil P of the eyeball 50 using the light-receiving unit 2's light-receiving signal of light Lo.

[0056] In the position detection device 100, for example, among the multiple light-emitting units, the light-emitting unit that emits light is switched sequentially. As a result, even if the eyeball 50 moves in response to a change in the line of sight of the wearer 300 or the like, at least one of the light beams Lo derived from the light beams Li1 emitted from the multiple light-emitting units is incident on the light-receiving unit 2. As a result, even if the eyeball 50 moves in response to a change in the line of sight of the wearer 300 or the like, the position detection device 100 can receive the light beam Lo at the light-receiving unit 2 and detect the position of the pupil P of the eyeball 50 based on the light-receiving signal of the light-receiving unit 2.

[0057] From another perspective, the position detection device 100 reduces the number of times that the laser light reflected by the eyeball 50 does not enter the light receiving unit 2 even when the eyeball 50 rotates, thereby expanding the range over which the position of the pupil P can be detected. The light receiving unit 2 detects slight movements of the laser light based on the rotational movement of the eyeball 50, and the arrangement of multiple light emitting units in the light source unit 1 detects coarse movements of the laser light based on the rotational movement of the eyeball 50, thereby achieving both high detection resolution and a wide detection range in detecting the rotation angle of the rotational movement of the eyeball 50.

[0058] The light-emitting units in the light source unit 1 can be switched in time series by a drive signal from the processing unit in accordance with the movement of the eyeball 50. Furthermore, controlling the light-emitting units in accordance with the rotational movement of the eyeball 50 improves the efficiency of light use and shortens the estimation time. However, it is not necessarily necessary to switch the light-emitting units of the light source unit 1 in accordance with the rotational movement of the eyeball 50. For example, the position detection device 100 may raster scan (sequentially emit light) the light-emitting units of the light source unit 1 at predetermined time intervals independent of the eyeball movement, and detect the coarse movement position of the eyeball 50 based on the detection signal of the light-receiving unit 2 at that time.

[0059] [Second embodiment] Next, a position detection device according to a second embodiment of the present invention will be described. Note that the same names and symbols as those in the previously described embodiments indicate the same or similar components or configurations, and detailed descriptions will be omitted as appropriate. This also applies to the following embodiments.

[0060] FIG. 9 is a schematic perspective view showing an adjustment mechanism 23 in a position detection device according to a second embodiment of the present invention.

[0061] The position detection device of the second embodiment of the present invention differs from the position detection device 100 of the first embodiment of the present invention in that it has an adjustment mechanism 23 for adjusting the relative position of the optical deflection unit 5 and the light receiving unit 2, and the adjustment mechanism 23 is arranged on the support unit 4.

[0062] The adjustment mechanism 23 shown in Figure 9 includes a coupling member 231 including a bending portion 231a, a first screw member 232 that couples the coupling member 231 to the second mounting substrate 21, and a second screw member 233 and a third screw member 234 that couple the coupling member 231 to the support portion 4.

[0063] The first screw member 232 includes a screw head and a threaded portion. The first screw member 232 couples the coupling member 231 and the second mounting substrate 21 by fitting the threaded portion inserted into a through hole formed in the coupling member 231 into a screw hole formed in the second mounting substrate 21 and pressing the coupling member 231 with the screw head.

[0064] The second screw member 233 and the third screw member 234 each include a screw head and a threaded portion. The second screw member 233 and the third screw member 234 join the joining member 231 and the support portion 4 by inserting the threaded portion into a through hole formed in the joining member 231 and joining the threaded portion to a screw hole formed in the support portion 4, and pressing the joining member 231 with the screw head.

[0065] In the adjustment mechanism 23, the diameters of the through holes of the coupling member 231 corresponding to the first screw member 232, the second screw member 233, and the third screw member 234 are larger than the diameters of the first screw member 232, the second screw member 233, and the third screw member 234. In other words, the through holes of the coupling member 231 have play with respect to the corresponding first screw member 232, the second screw member 233, and the third screw member 234. By utilizing this play, the relative position of the coupling member 231 with respect to the second mounting substrate 21 can be adjusted, and also the relative position of the coupling member 231 with respect to the support 4 can be adjusted. As a result, the relative position between the second mounting substrate 21 and the support 4 can be adjusted via the coupling member 231, and the relative position between the optical deflection unit 5 supported by the support 4 and the light receiving unit 2 mounted on the second mounting substrate 21 can be adjusted.

[0066] By adjusting the relative position between the light deflection unit 5 and the light receiving unit 2 using the adjustment mechanism 23, the light Lo reflected by the eyeball 50 is incident on the light receiving unit 2 at an appropriate position and angle. This increases the detection accuracy of the pupil P in the position detection device according to the second embodiment of the present invention. Note that the adjustment mechanism 23 is not limited to a configuration having a connecting member 231, and a slider mechanism, a linear stage, or the like may also be used.

[0067] The position detection device according to the second embodiment of the present invention has the same effects as the position detection device 100 according to the first embodiment of the present invention, except for the effects described above.

[0068] [Third embodiment] Next, a position detection device according to a third embodiment of the present invention will be described. Fig. 10 is a schematic perspective view showing an elastic member 6 in a position detection device 100 according to the third embodiment of the present invention.

[0069] The position detection device 100 of the third embodiment of the present invention differs from the position detection device 100 of the first embodiment of the present invention in that it has an elastic member 6 that is arranged between the connection portion 3 and the head-mounted display 200 and has greater elasticity than the connection portion 3.

[0070] 10, the connection unit 3 is connected to the lower surface 203a of the holding unit 203 of the head mounted display 200 via the elastic member 6. For example, an adhesive member is provided on the surface of the elastic member 6 facing the lower surface 203a and the surface facing the connection unit 3. The elastic member 6 adheres the connection unit 3 and the lower surface 203a of the holding unit 203, so that the connection unit 3 can be connected to the lower surface 203a of the holding unit 203 via the elastic member 6. However, the method of connecting the connection unit 3 to the head mounted display 200 via the elastic member 6 is not limited to the above method and can be changed as appropriate depending on the configuration, material, etc. of the elastic member 6.

[0071] The elastic member 6 has greater elasticity than the connection portion 3, and therefore can absorb shocks, vibrations, and the like applied to the head-mounted display 200, reducing the transmission of the shocks, vibrations, and the like to the position detection device 100. This reduces displacement of the components included in the position detection device 100 due to shocks, vibrations, and the like, and reduces the decrease in detection accuracy of the position detection device 100 that accompanies displacement of the components.

[0072] The elastic member 6 can be made of rubber or a spring material that has greater elasticity than the connecting portion 3, or a material made of a resin material. When a material made of a resin material is used, it is preferable that the elastic member 6 made of a resin material has higher flexibility than the connecting portion 3, from the viewpoint of suitably absorbing shocks, vibrations, and the like.

[0073] Although the preferred embodiments have been described in detail above, the present invention is not limited to the above-described embodiments, and various modifications and substitutions can be made to the above-described embodiments of the present invention without departing from the scope of the claims.

[0074] All ordinal numbers, quantitative numbers, and other figures used in the description of the embodiments of the present invention are provided as examples to specifically explain the technology of the present invention, and the present invention is not limited to the illustrated figures. Furthermore, the connection relationships between components are provided as examples to specifically explain the technology of the present invention, and do not limit the connection relationships that realize the functions of the present invention.

[0075] For example, aspects of the present invention are as follows. <1> A pupil or cornea position detection device that can be attached to a head-mounted display and detects the position of the pupil or cornea of ​​a wearer of the head-mounted display, the pupil or cornea position detection device having a light source unit, a light receiving unit that receives at least a portion of the light emitted from the light source unit and reflected by the eyeball of the wearer, a connection unit that connects to the head-mounted display, and a support unit that supports the light source unit and the light receiving unit as a single unit, the connection unit connecting to the head-mounted display in an upward direction that intersects with the wearer's normal viewing direction of the light source unit and the light receiving unit supported by the support unit. <2> the light source unit and the light receiving unit are arranged in a vertical direction and a horizontal direction intersecting the vertical direction with respect to the eyeball when viewed from the normal viewing direction, <1> 1. A pupil or cornea position detection device according to claim 1. <3> a light deflection unit that is disposed in an optical path between the light source unit and the eyeball when the pupil or cornea position detection device is attached to the head-mounted display worn by the wearer, and that deflects light emitted from the light source unit in a direction toward the position of the eyeball; the light receiving unit receives at least a part of the light that has been deflected by the light deflection unit and then reflected by the eyeball; <1> or the above <2> 1. A pupil or cornea position detection device according to claim 1. <4> a mechanism for adjusting the relative position of the light deflection unit and the light receiving unit, the mechanism being disposed on the support unit; <3> 1. A pupil or cornea position detection device according to claim 1. <5> the support portion is located below the eyeball, includes an extension portion that extends in a left-right direction that intersects both the up-down direction and the normal viewing direction, and supports the light deflection portion at a position on the opposite side of the eyeball from the light source portion in the left-right direction. <3> 1. A pupil or cornea position detection device according to claim 1. <6> The connecting portion, the supporting portion, and the extending portion are integrally formed. <5> 1. A pupil or cornea position detection device according to claim 1. <7> the support portion includes a first flat portion that is disposed at a first angle with respect to a reference plane of the extension portion in a top view and that supports the light source portion, and a second flat portion that is disposed at a second angle with respect to the reference plane of the extension portion that is different from the first angle and that supports the light receiving portion, <5> or the above <6> 1. A pupil or cornea position detection device according to claim 1. <8> the connecting portion is located between the light source portion and the light receiving portion in the normal viewing direction; <1> From the above <7> The pupil or cornea position detection device is described in any one of the above. <9> the light source unit and the light receiving unit are located between the connecting unit and the supporting unit in a vertical direction intersecting with a normal viewing direction of the wearer. <1> From the above <8> The pupil or cornea position detection device is described in any one of the above. <10> an elastic member disposed between the connection portion and the head-mounted display and having greater elasticity than the connection portion; <1> From the above <9> The pupil or cornea position detection device is described in any one of the above. <11> the light source unit includes a vertical cavity surface emitting laser; <1> From the above <10> The pupil or cornea position detection device is described in any one of the above. <12> The aforementioned <1> From the above <11> A head-mounted display having the pupil or cornea position detection device described in any one of the above. <13> a display unit and a holding unit that holds the display unit, and the connecting unit is connected to a lower surface of the holding unit; <12> 2. The head-mounted display according to claim 1, <14> When the head-mounted display is worn by the wearer, the pupil or cornea position detection device is disposed on the opposite side of the display unit with respect to either the right eye or the left eye of the wearer. <12> 2. The head-mounted display according to claim 1, <15> a pupil or cornea position detection device for the right eye of the wearer, and a pupil or cornea position detection device for the left eye of the wearer, wherein, when the head mounted display is worn by the wearer, the connection portion of the pupil or cornea position detection device for the right eye is disposed on the opposite side of the display unit for the left eye of the wearer, with the display unit for the right eye of the wearer as a reference, and the connection portion of the pupil or cornea position detection device for the left eye is disposed on the opposite side of the display unit for the right eye of the wearer, with the display unit for the left eye of the wearer as a reference. <13> or the above <14> 2. The head-mounted display according to claim 1, [Explanation of symbols]

[0076] 1 Light source section 11 First mounting board 12 1st plane part 2 Light receiving section 21 Second mounting board 22 Second plane part 23 Adjustment mechanism 231 Connecting members 231a Bend section 232 First screw member 233 Second screw member 234 Third screw member 3 Connection 3a top edge 4 Support part 41 Stretching section 41a top end 410 Reference plane 5 Light deflection section 6 Elastic member 50 Eyeball 50a top end 50b bottom end 100 Position detection device 200 Head-Mounted Display 201 Mounting part 202 Display section 202a Right eye display 202b Left eye display 203 Holding part 203a Bottom surface 300 wearers 300H head 300N nose Li1, Li2, Lo, Li1', Li2', Lo' light P pupil N Direction of normal viewing W1 1st width W2 Second width W3 3rd width θ1 First angle θ2 Second angle [Prior art documents] [Patent documents]

[0077] [Patent Document 1] US Patent Application Publication No. 2016 / 0166146

Claims

1. A pupil or cornea position detection device of a wearer of a head-mounted display, which is attachable to the head-mounted display, A light source unit; a light receiving unit that receives at least a portion of light emitted from the light source unit and reflected by the eyeball of the wearer; a connection portion for connecting to the head mounted display; a support portion that integrally supports the light source portion and the light receiving portion, the connecting portion is connected to the head mounted display in an upward direction intersecting with a normal viewing direction of the wearer of the light source portion and the light receiving portion supported by the supporting portion. Pupil or corneal position detection device.

2. 2. The pupil or cornea position detection device according to claim 1, wherein the light source unit and the light receiving unit are arranged in a vertical direction and a horizontal direction intersecting the vertical direction and the horizontal direction intersecting the horizontal direction with respect to the eyeball when viewed from the normal viewing direction.

3. a light deflection unit that is disposed in an optical path between the light source unit and the eyeball when the pupil or cornea position detection device is attached to the head-mounted display worn by the wearer, and that deflects light emitted from the light source unit in a direction toward the position of the eyeball; The pupil or cornea position detection device according to claim 1 , wherein the light receiving unit receives at least a part of the light that has been deflected by the light deflection unit and then reflected by the eyeball.

4. a mechanism for adjusting the relative position of the light deflection unit and the light receiving unit, The pupil or cornea position detection device according to claim 3 , wherein the adjustment mechanism is disposed on the support portion.

5. 4. The pupil or cornea position detection device according to claim 3, wherein the support portion is located below the eyeball and includes an extension portion that extends in a left-right direction that intersects both the up-down direction and the normal viewing direction, and supports the light deflection portion at a position in the left-right direction opposite the light source portion with respect to the eyeball.

6. The pupil or cornea position detection device according to claim 5 , wherein the connecting portion, the supporting portion, and the extending portion are integrally formed.

7. The support portion, when viewed from above, a first planar portion disposed at a first angle with respect to a reference plane of the extension portion and supporting the light source portion; 6. The pupil or cornea position detection device according to claim 5, further comprising: a second flat portion that is disposed at a second angle different from the first angle with respect to a reference plane of the extension portion and that supports the light receiving portion.

8. the connecting portion is located between the light source portion and the light receiving portion in the normal viewing direction; 2. The pupil or cornea position detection device according to claim 1.

9. the light source unit and the light receiving unit are located between the connecting unit and the supporting unit in a vertical direction intersecting with a normal viewing direction of the wearer.

2. The pupil or cornea position detection device according to claim 1.

10. The pupil or cornea position detection device according to claim 1 , further comprising an elastic member disposed between the connection portion and the head-mounted display, the elastic member having greater elasticity than the connection portion.

11. The pupil or cornea position detection device according to claim 1 , wherein the light source unit includes a vertical cavity surface emitting laser.

12. A head-mounted display comprising the pupil or cornea position detection device according to any one of claims 1 to 11.

13. A display unit; a holder for holding the display unit, The head mounted display according to claim 12 , wherein the connection portion is connected to a lower surface of the holding portion.

14. When the head-mounted display is worn by the wearer, The head mounted display according to claim 13 , wherein the pupil or cornea position detection device is disposed on the opposite side of the display unit with respect to either the right eye or the left eye of the wearer.

15. a pupil or cornea position detection device for the wearer's right eye; a pupil or cornea position detection device for the wearer's left eye, When the head-mounted display is worn by the wearer, the connection portion of the pupil or cornea position detection device for the right eye is disposed on an opposite side of the display portion for the left eye of the wearer with respect to the display portion for the right eye of the wearer; The head-mounted display according to claim 13, wherein the connection portion of the pupil or cornea position detection device for the left eye is positioned on the opposite side of the display portion for the wearer's right eye with respect to the display portion for the wearer's left eye.

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