Video display device

Abstract

To provide a video display device capable of simultaneously using a position detecting means and a line-of-sight detecting means.SOLUTION: An optical unit including a display unit and an optical element, a driving unit configured to drive the optical element, a position detection unit configured to detect a position of the driving unit by transmitting and receiving infrared light, and a line-of-sight detection unit configured to detect a line of sight of a user by using infrared light, when an angle range facing the outside of the circle is assumed on the basis of the directional angle of the light emitting part, the direction of light emission from the light emitting part is included in the angle range, or the direction of light emission is not included in the angle range and an angle formed by the line-of-sight detection direction of the line-of-sight detection means and the position detection direction of the position detection means is larger than the directional angle.SELECTED DRAWING: Figure 3

Description

[Technical Field]

[0001] The present invention relates to a technique for adjusting a focal length in a video display device, and in particular to the use of the focal length in combination with a line-of-sight detection function. [Background technology]

[0002] There are image display devices that users wear on their heads. These devices can display 3D images using binocular parallax between the left and right eyes. For example, VR (Virtual Reality) These include VR devices, AR (Augmented Reality) devices, and MR (Mixed Reality) devices.

[0003] In these image display devices, a vergence accommodation conflict (VAC) occurs due to a mismatch between the convergence distance and accommodation distance (or focal length) of both eyes, causing a problem for the user. This may increase the burden on the user. To solve this problem, a variable focus mechanism has been proposed that can change the adjustment distance of the display optical system. A variable focus mechanism controls and drives an optical element along the optical axis using a driving means such as a motor based on position information from a position detection means. High-precision position detection means include optical encoders that detect position using infrared light. These image display devices also have gaze detection means, which enable functions such as menu selection based on the detection results. A common gaze detection means is a configuration that uses the corneal reflex method to detect the gaze using infrared light.

[0004] Patent Document 1 discloses an imaging device having a line-of-sight detection means that uses infrared light and an eye proximity detection function that detects the approach of a face. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-093624 Summary of the Invention [Problem to be solved by the invention]

[0006] The prior art disclosed in the above-mentioned patent document involves switching the timing of light emission from the light source for gaze detection and eye proximity detection. Therefore, gaze detection and eye proximity detection cannot be used simultaneously. Furthermore, in an image display device in which both the position detection means and the gaze detection means use infrared light, if both are used simultaneously, there is a possibility that they may interfere with each other, for example, when infrared light emitted by the position detection means is incident on the gaze detection means.

[0007] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide an image display device that can simultaneously use a position detection unit and a line of sight detection unit. [Means for solving the problem]

[0008] The video display device according to the present invention comprises: A head-mounted image display device, an optical unit having a display unit and an optical element; a driving means for driving at least one of the display unit and the optical element; a position detection means having a first light-emitting unit that irradiates a first infrared light and a first light-receiving unit that receives the first infrared light irradiated from the first light-emitting unit, and that detects the position of the driving means; a second light emitting unit that emits second infrared light; and a second light emitting unit that emits second infrared light and that is incident on the user's eye. a second light receiving unit that captures the second infrared light reflected by the light receiving unit, and a line of sight detection unit that detects the line of sight of the user; Equipped with a direction in which the first light-emitting unit of the position detection means is pointed is defined as a position detection direction, and a range of an angle θ (θ<90°) from the position detection direction is defined as a directivity angle; In a projection diagram in which the position detection means and the line of sight detection means are projected onto a plane perpendicular to the optical axis direction of the optical unit, when a position where a virtual circle having a radius equal to the distance from the optical axis to the first light-emitting unit overlaps with the first light-emitting unit is defined as the origin of the first infrared light, and a tangent to the virtual circle at the origin is divided into a first portion and a second portion with the origin as the boundary, a first line segment is drawn from the origin to the opposite side of the virtual circle so that the angle between the first portion is θ, and a second line segment is drawn from the origin to the opposite side of the virtual circle so that the angle between the second portion is θ, and the angle between the first line segment and the second line segment is defined as an angle range R, Either (i) or (ii) below is satisfied: (i) The position detection direction of the position detection means is included in the angle range R. (ii) The position detection direction of the position detection means is not included in the angle range R, and the angle formed by the position detection direction and the line-of-sight detection direction, which is the direction in which the second light receiving unit of the line-of-sight detection means is pointed, is larger than the directivity angle. A video display device characterized by: [Effects of the Invention]

[0009] According to the present invention, it is possible to provide an image display device that can simultaneously use a position detection means and a line of sight detection means. [Brief explanation of the drawings]

[0010] [Figure 1] Detailed configuration diagram of the optical unit of the image display device [Figure 2] A diagram illustrating an area where a position detection unit and a line-of-sight detection unit can be arranged. [Figure 3] 1 is a diagram illustrating a first embodiment; [Figure 4] FIG. 10 is a diagram illustrating a modification of the first embodiment. [Figure 5] FIG. 10 is a diagram illustrating a second embodiment. [Figure 6] FIG. 10 is a diagram illustrating a third embodiment. [Figure 7]FIG. 10 is a diagram illustrating the position of the line of sight detection means in the optical axis direction in the second embodiment. [Figure 8] FIG. 10 is a diagram illustrating the position of the line of sight detection means in the optical axis direction in the second embodiment. [Figure 9] A diagram illustrating the appearance and main body of a head-mounted image display device. [Figure 10] Diagram explaining the optical encoder and gaze camera [Figure 11] Diagram explaining the directivity of the light source of an optical encoder [Figure 12] Diagram explaining the direction of light in an optical encoder DETAILED DESCRIPTION OF THE INVENTION

[0011] Preferred embodiments of the present invention will be described in detail below with reference to the drawings. However, unless otherwise specified, the dimensions, materials, shapes, relative positions, and the like of the components described in these embodiments are not intended to limit the scope of the present invention to those dimensions. Furthermore, the materials, shapes, and the like of components described once in the following description will remain the same in subsequent descriptions unless otherwise specified. Well-known or publicly known technologies in the relevant technical field can be applied to configurations and processes not specifically illustrated or described. Furthermore, the present invention is not limited to these embodiments, and not all of the combinations of features described in the embodiments are necessarily essential to the solution of the present invention.

[0012] <Embodiment> First, a configuration common to each embodiment will be described with reference to the drawings.

[0013] [Explanation about eye position adjustment] 9 shows a head mounted display as a head-mounted image display device according to the present disclosure, hereinafter referred to as HMD 100. First, eye position adjustment during viewing will be described.

[0014] The HMD 100 can display a good image when the relative positions of the user's eyes and the optical unit 20 are within an appropriate range. Therefore, the user generally adjusts the wearing position beforehand. This adjustment positions the left eye 4a and right eye 4b near the center of the optical axis of the eyepiece lenses 12a and 12b.

[0015] 9(a) is an external view of the HMD 100, which is composed of a main body 1, a head-mounted mechanism 2, and a connecting mechanism 3 that connects the main body 1 and head-mounted mechanism 2 of the HMD 100. The tightening force of the headband-shaped band of the head-mounted mechanism 2 can be adjusted using an adjustment mechanism (not shown). The connecting mechanism 3 includes a vertical shift mechanism and a tilt mechanism, and can change the angle and relative distance between the main body 1 and the head-mounted mechanism 2.

[0016] 9(b) is a front view of the main body 1 as seen from the user's viewing side. The main body 1 has a left optical unit 20a that displays an image for the user's left eye 4a and a right optical unit 20b that displays an image for the user's right eye 4b. The drive mechanisms 21a and 21b are rotary motors that independently move the left optical unit 20a and the right optical unit 20b in a first direction (arrow Sx in the figure).

[0017] As described above, the vertical direction is adjusted by the connecting mechanism 3 and the band position of the head mounting mechanism 2 in FIG. 9(a), and the horizontal direction is adjusted by the drive mechanism 21.

[0018] [Detailed explanation of the overall optical unit configuration] Next, the entire optical system will be described. FIG. 1 is a diagram illustrating the detailed configuration of the optical unit 20 shown in FIG. 9(b). The symbols "a" are added to the reference numerals of components related to the user's left eye 4a, and the symbols "b" are added to the reference numerals of components related to the user's right eye 4b to distinguish them. For example, the optical units 20 are referred to as the optical unit 20a for the left eye and the optical unit 20b for the right eye. Note that when it is not necessary to distinguish between left and right, or when it is clear which one is being referred to, the symbols "a" or "b" are omitted and the unit is simply referred to as the optical unit 20.

[0019] 1, a display panel 10 as a display unit for displaying a viewing image, a driven lens 11, and an eyepiece 12 are arranged in this order on an optical axis 13 to realize an optical system that achieves a wide viewing angle. The optical elements include at least the driven lens 11. The driven lens 11 and the eyepiece 12 may be a single lens or a lens group consisting of multiple lenses.

[0020] Driven lens 11 is mounted on frame 14 and driven by motor 18, which serves as driving means, along guide 17 in the direction of the arrow in the figure on the optical axis. Because the distance between driven lens 11 and display panel 10 is variable, the focal length of the optical system of optical unit 20 can be changed by mechanical operation. Types of motor 18 include stepping motors, voice coil motors, and ultrasonic motors. The movement of motor 18 is detected by optical encoder 15, which serves as position detection means. The motor is feedback-controlled based on the position information obtained from optical encoder 15.

[0021] In FIG. 1, the driven lens 11 is configured to be driven by the motor 18. A variable focus function can be realized by driving at least one of the driven lens 10 and the driven lens 11. In other words, the driving means only needs to be able to change the distance between the driven lens 11 and the display panel 10 in the optical axis direction.

[0022] In addition, in Figure 1, the motor 18 and the optical encoder 15 are drawn side by side in the optical axis direction, but this is a schematic illustration of the two being placed close to each other, and the actual positional relationship is not limited to this.

[0023] The display panel 10 and eyepiece lens 12 in Figure 1 are fixed in place by a lens barrel structure (not shown). The guide 17 for the driven lens 11 is also fixed to the lens barrel structure. The lens barrel of the HMD 100 is often made of a black resin material so that it is not affected by visible light that enters from the outside before the image on the display panel 10 reaches the eye. The lens barrel structure only needs to function as a fixing part, and there is a high degree of freedom in its shape.

[0024] The gaze camera 16, which serves as a gaze detection means, is disposed at the eye-side end of the optical unit 20. The gaze camera 16 is fixed to a lens barrel structure (not shown). As shown in FIG. 10(b), the gaze camera 16 emits near-infrared light (second infrared light) from a light source 161 (second light-emitting unit), such as an infrared LED, fixed to the lens barrel structure. The image of the infrared light reflected by the user's eye is captured by an image sensor 162 (second light-receiving unit), thereby detecting the user's gaze direction. Near-infrared light is typically light with a wavelength of approximately 750 nm to 1000 nm. However, the wavelength of the gaze camera 16 is not necessarily limited to the near-infrared region, as long as it is capable of gaze detection.

[0025] As described above, the user's eye is adjusted in advance to be near the center of the optical axis. Therefore, the eye camera 16 is fixed facing in a direction that clearly captures the eye near the center of the optical axis. Furthermore, to reliably capture a reflected image, the eye camera is fixed as close to the inner diameter as possible at the center of the optical axis.

[0026] [Explanation of optical encoder] FIG. 10(a) is a cross-sectional view illustrating the optical encoder 15 used in this embodiment. The head unit 30 includes an LED 32 (first light-emitting unit) that emits near-infrared light (first infrared light), and a photodiode 34 (first light-receiving unit). The surface of the scale unit 31 that faces the head unit 30 is provided with a slit 33. The slit 33 has aluminum reflecting portions arranged at regular intervals. The near-infrared light emitted from the LED 32 is reflected by the slit 33 and then enters the photodiode 34. The optical encoder 15 can detect the position and amount of displacement by analyzing the electrical signal output from the photodiode 34.

[0027] The directivity of the near-infrared light emitted by the LED 32 of the head unit 30 is represented by the dashed line in Figure 11(a). The angle at which the output drops to half of the central ray with the highest output is generally used to represent directivity. Figure 11(b) is an example of the light distribution of the LED 32, showing that the output is 0.5 when the directivity angle θ = 60°. The directivity angle θ can be measured as a product-specific value using an illuminance meter that uses a photodiode.

[0028] 10(a), most of the near-infrared light emitted from the LED 32 at a directivity angle θ is irradiated onto the back surface of the scale unit 31 without entering the scale unit 31. Since near-infrared light is highly transparent, it is irradiated onto components arranged in front of the LED 32. However, the wavelength of the optical encoder 15 is not necessarily limited to the near-infrared region, as long as it is capable of detecting the line of sight.

[0029] In FIG. 1, the head portion 30 and the scale portion 31 of the optical encoder 15 are driven lenses. The head unit 30 is preferably fixed to a lens barrel structure or the like because it is connected to a power supply means (not shown). The scale unit 31 is also disposed on a frame 14 that is driven in synchronization with the driven lens 11. This allows the position detection means to detect the position and amount of movement of the motor 18 and driven lens 11.

[0030] [Explanation of where to place the gaze camera and optical encoder] 2 is a diagram illustrating where the gaze camera 16 and optical encoder 15 can be placed on the HMD 100. In FIG. 2, the horizontal axis represents the horizontal position of the HMD 100, the vertical axis represents the vertical position of the HMD 100, and the intersection of the coordinate axes is the center of the optical axis of the optical unit 20. The positive side of the horizontal axis represents the inside of the HMD 100, that is, the side closer to the user's nose. On the other hand, the negative side of the horizontal axis represents the outside, that is, the side farther from the user's nose.

[0031] In Figure 2(a), the gaze camera 16 is placed in the lower half of the range from the center of the optical axis. This is because the lower half is the best position for detecting gaze direction due to the structure of the human eye. As for the number of gaze cameras 16, one or two cameras are placed within the hatched area per optical unit 20, and it is well known that the greater the number, the higher the detection performance. The hatched area in Figure 2(a) is the area below the horizontal line passing through the optical axis of the optical unit 20, and is referred to as the gaze camera placement area 70.

[0032] In Figure 2(b), the optical encoder 15 is placed in the outer half of the range from the center of the optical axis. First, there is no space to place the motor 18 in Figure 1 inside where the nose is, so the motor is necessarily positioned on the outer side. Second, placing the optical encoder 15 near the motor 18 allows for more accurate detection, so the optical encoder 15 is also positioned on the outer side. The hatched area in Figure 2(b) is the area outside the vertical line passing through the optical axis of the optical unit 20 in the figure, and is called the optical encoder placement area 72.

[0033] [Description of Common Portions in the First to Third Embodiments] 3 to 6 are diagrams illustrating first to third embodiments of the present invention. These diagrams show the circumferential installation positions of the optical encoder 15 and the gaze camera 16 in the optical unit 20 for the left eye, projected onto a plane perpendicular to the optical axis of the optical unit 20. Arrows also indicate the optical axis directions in which the LED 32 of the optical encoder 15 and the image sensor 162 of the gaze camera 16 face. For simplicity, the symbol "a" indicating the left eye side has been omitted.

[0034] In the figure, the illumination range of the LED 32 of the optical encoder 15 is represented by an arrow A indicating the illumination direction of the LED 32 and a directivity angle (half-value angle) θ indicating the directivity. Here, the arrow with the starting point of the illumination direction A of the LED 32 of the optical encoder 15 moved to the coordinate origin is defined as illumination direction A'. The direction in which the LED 32 is pointed is defined as the position detection direction. The position detection direction may also be considered to be the direction of the central optical axis of the infrared light emitted from the LED 32 as it travels in a cone shape. The position detection direction may also be considered to be the direction of the infrared light with the highest intensity emitted from the LED 32.

[0035] The direction in which the gaze camera 16 is pointed is defined as the gaze detection direction. The gaze detection direction may be considered to be the direction in which the installed gaze camera 16 can detect incident infrared light with the highest sensitivity. The gaze detection direction may also be the front direction set during the design of the gaze camera 16. In this case, the angle Φ is the angle between the irradiation direction A' (position detection direction) and the incident direction B to the gaze camera 16 (gaze detection direction).

[0036] In this figure, the distance from the optical axis of both devices is meaningless. In this application, the area in which the values ​​of both the X and Y axes are positive is defined as the first quadrant. The quadrants are designated counterclockwise from there as the second to fourth quadrants. In the figure, the first to fourth quadrants for the optical unit 20a for the left eye are indicated by symbols I to IV. When considering the optical unit 20b for the right eye, the left side, which corresponds to the nose, is positive on the X axis. The region where both the X and Y axis values ​​are positive is designated as the first quadrant, and the quadrants are designated clockwise from there as the second to fourth quadrants.

[0037] (First embodiment) FIG. 3 is a diagram illustrating the first embodiment. The optical unit 20 of this embodiment has one gaze camera 16. The optical encoder 15 is located in the second quadrant, and the gaze camera 16 is located near the X-axis, which is the boundary between the first and second quadrants. As shown in the figure, the LED 32 of the optical encoder 15 is located inside the lens barrel of the optical unit 20, that is, facing the center of the optical axis and facing the gaze camera 16. In this case, near-infrared light has high transparency and passes through the lens barrel structure. However, in this embodiment, the relationship between the angle Φ between the irradiation direction A' and the incident direction B and the directivity angle θ is set to Φ>θ, thereby preventing errors from occurring.

[0038] If Φ<θ, the light illuminating the area inside the dashed line, i.e., the area less than the beam angle θ, has a high output, which may result in bright light spots being captured as video information by the eye camera 16. Data containing such unnecessary video information may cause errors in post-processing. On the other hand, by setting Φ>θ as in this embodiment, the output of near-infrared light captured by the eye camera 16 can be kept within a low range, and the video information will be visualized as dark light spots. This allows unnecessary video information to be easily excluded in post-processing.

[0039] (Variation) FIG. 4 is a diagram illustrating a modification of the first embodiment having one gaze camera 16. In this modification, the optical encoder 15 is placed in the second quadrant, and the gaze camera 16 is placed in the third quadrant. As shown in the figure, the magnitude relationship of the angle Φ between the irradiation direction A' and the incident direction B is Φ>θ. If the angle relationship is Φ>θ, the output of the near-infrared light emitted from the LED 32 when it enters the gaze camera 16 can be kept within a low range. Therefore, even when both the optical encoder 15 and the gaze camera 16 are placed outside the Y axis, error occurrence can be prevented as in the first embodiment.

[0040] (Second embodiment) 5 is a diagram illustrating the second embodiment. The optical unit 20 of this embodiment has a plurality of eye cameras 16. Explanation of parts having the same configuration and function as the first embodiment will be omitted.

[0041] As shown in the figure, an optical encoder 15 is placed in the second quadrant. Furthermore, eye cameras 16 are placed in the third and fourth quadrants. For convenience, the two eye cameras 16 are referred to as a first eye camera 16(α) and a second eye camera 16(β), respectively. In this case, if the optical encoder 15 is oriented toward the center of the optical axis as in the first embodiment, near-infrared light with a high output and a directivity angle θ or less may be incident on one of the two eye cameras 16, and may be captured as unnecessary video information.

[0042] Therefore, in this embodiment, the optical encoder 15 is positioned so that the direction of irradiation from the LED 32 of the optical encoder 15 is vertically upward. As a result, when the angle between the irradiation direction A' and the incident direction B1 of the first eye camera 16(α) is Φ1, Φ1>θ holds. Also, when the angle between the irradiation direction A' and the incident direction B2 of the second eye camera 16(β) is Φ2, Φ2>θ holds. This suppresses the intensity of near-infrared light incident on the eye camera 16, preventing errors from occurring.

[0043] 7 and 8 show the optical encoder 15 (head portion) in the second embodiment shown in FIG. 30 and scale unit 31) and the optical axis direction of the gaze camera 16, projected onto a vertical plane including the optical axis of the optical unit 20. In this figure, a plane perpendicular to the optical axis that passes near the LED of the head unit 30 of the optical encoder 15 is defined as a position detection plane P1. Also, a plane perpendicular to the optical axis that passes through the image sensor 162 of the gaze camera 16 is defined as a gaze detection plane P2.

[0044] 7 and 8 differ in the position of the gaze detection plane P2. In FIG. 7, the gaze camera 16 is placed closer to the eye than the driven lens 11. Therefore, the gaze camera 16 is not affected by changes in the focal length of the entire optical system due to movement of the driven lens 11. Therefore, this is a common configuration that is relatively easy technically; however, because the gaze camera 16 protrudes toward the eye, the size of the optical unit 20 is large. In this configuration, the gaze camera 16 faces the eye (right side of the figure) to photograph the eye, and the position detection plane P1 is located on the back side of the gaze camera 16. In other words, for the gaze camera 16 to capture the near-infrared light emitted from the head unit 30, the near-infrared light must reflect at least one time. Because the light intensity decreases due to reflection, the configuration in FIG. 7 is less likely to cause detection errors.

[0045] On the other hand, in Figure 8, the gaze camera 16 is placed closer to the panel than the driven lens 11. As a result, the gaze camera 16 is affected by changes in the focal length of the entire optical system caused by the movement of the driven lens 11. Therefore, although this is a technically difficult configuration, the gaze camera 16 is embedded in an empty space near the display panel 10, which makes it possible to reduce the size of the optical unit 20. Since the size of the optical unit 20 has a large impact on the overall size of the HMD 100, and with demand for a smaller optical unit 20 increasing, Figure 8 is a promising configuration.

[0046] In the configuration of Figure 8, the gaze camera 16 is facing the eye on the right side of the figure to capture an image of the eye, and the position detection plane P1 is on the front side of the gaze camera 16. In other words, there is a risk that near-infrared light emitted from the head unit 30 will directly enter the image sensor of the gaze camera 16. However, by arranging the LED 32 of the optical encoder 15 facing vertically upward as in the second embodiment of Figure 5, it is possible to prevent the occurrence of errors and reduce the size of the optical unit 20.

[0047] (Third embodiment) 6 is a diagram illustrating a third embodiment. An optical unit 20 of this embodiment has two eye cameras 16. Descriptions of configurations and functions similar to those of the first and second embodiments will be omitted.

[0048] As shown in the figure, an optical encoder 15 is placed in the third quadrant. Furthermore, eye cameras 16 are placed in the third and fourth quadrants. For convenience, the two eye cameras 16 are referred to as a first eye camera 16(α) and a second eye camera 16(β), respectively.

[0049] In this embodiment, as shown in the figure, the LED 32 of the optical encoder 15 is arranged facing outward. For the first line of sight camera 16(α) in the fourth quadrant, when the angle between the illumination direction A' and the incident direction B1 is Φ1, the magnitude relationship of the angles is Φ1>θ, which prevents the occurrence of errors. This is the same as in the first and second embodiments.

[0050] On the other hand, for the second gaze camera 16 (β) in the third quadrant, when the angle between the illumination direction A' and the incident direction B2 is Φ2, Φ2<θ, and the condition for preventing the occurrence of an error (Φ>θ) does not apply. In this case, it is preferable to make the distance from the optical center of the optical encoder 15 to the LED 32 longer than the distance from the optical center of the gaze camera 16 to the image sensor 162. In other words, the distance from the optical axis on the position detection plane P1 to the LED 32 is made longer than the distance from the optical axis on the gaze detection plane P2 to the image sensor 162. By doing so, the LED 32 can be illuminated from the back side of the gaze camera 16. Therefore, the near-infrared light is reflected at least once before it is captured by the image sensor 162. Therefore, the intensity of the light entering the image sensor 162 is low, which can prevent errors from occurring.

[0051] Here, using FIG. 12, we will generally explain what it means when the LED 32 faces outward in the third embodiment. FIG. 12, expressed in the same way as FIG. 6, is a diagram showing the irradiation direction A of the optical encoder 15 projected onto a plane perpendicular to the optical axis of the optical unit 20. Here, we imagine a virtual circle C whose radius is the distance from the optical center (optical axis M) in the projection diagram to the light source (starting point L of the light emission of the LED 32), and a tangent line T at the starting point L of the virtual circle C. The tangent line T is then divided into a first portion Ta and a second portion Tb, with the starting point L as the boundary. Furthermore, a first line segment LSa is drawn from the starting point L on the opposite side of the virtual circle C, such that the angle between it and the first portion Ta is θ. Furthermore, a second line segment LSb is drawn from the starting point L on the opposite side of the virtual circle C, such that the angle between it and the second portion Tb is θ. The angle between the first line segment LSa and the second line segment LSb is defined as a predetermined angle range R. If the directivity angle θ is 90° or more, the angle range R cannot be defined, and the infrared light will travel backward from the light source. Therefore, the angle θ is defined as θ (θ<90°).

[0052] In this case, "outward" means that the direction of light emitted from the LED 32 is included in the angle range R. This angle range R can be defined at any position in the circumferential direction, and as long as the arrow A is within this angle range R, there is no need to consider the effect on the gaze camera 16.

[0053] On the other hand, the direction of the irradiation direction A described in the first embodiment shown in Fig. 3 and Fig. 4 and the second embodiment shown in Fig. 5 is "inward" rather than "outward." In Fig. 12, when the irradiation direction A is directed within a range not included in the angle range R, it is referred to as "inward."

[0054] In the first and second embodiments, even if the irradiation direction A is directed inward, the angle magnitude relationship is Φ>θ, so it is possible to prevent errors in gaze detection. To summarize the first to third embodiments, it is sufficient that (i) the position detection direction of the position detection means is included in the angle range R, or (ii) the position detection direction is not included in the angle range R, but the angle Φ between the position detection direction and the gaze detection direction is larger than the directivity angle θ.

[0055] As described above, according to the configuration of each embodiment, the light beam from the LED 32 of the optical encoder 15, which is the position detection means, does not directly enter the image sensor of the gaze camera 16, which is the gaze detection means. Therefore, even if the optical encoder 15 uses near-infrared light like the gaze camera 16, it does not affect the gaze detection result. Therefore, it is possible to provide an HMD 100 that can use the optical encoder 15 and the gaze camera 16 simultaneously.

[0056] [Configuration 1] A head-mounted image display device, an optical unit having a display unit and an optical element; a driving means for driving at least one of the display unit and the optical element; a position detection means having a first light-emitting unit that irradiates a first infrared light and a first light-receiving unit that receives the first infrared light irradiated from the first light-emitting unit, and that detects the position of the driving means; a gaze detection means having a second light-emitting unit that emits second infrared light and a second light-receiving unit that captures the second infrared light that is emitted from the second light-emitting unit and reflected by the user's eye, and that detects the gaze of the user; Equipped with The direction in which the first light emitting unit of the position detecting means is directed is defined as a position detecting direction, The range of angle θ (θ<90°) from the detection direction is defined as the directivity angle. In a projection diagram in which the position detection means and the line of sight detection means are projected onto a plane perpendicular to the optical axis direction of the optical unit, when a position where a virtual circle having a radius equal to the distance from the optical axis to the first light-emitting unit overlaps with the first light-emitting unit is defined as the origin of the first infrared light, and a tangent to the virtual circle at the origin is divided into a first portion and a second portion with the origin as the boundary, a first line segment is drawn from the origin to the opposite side of the virtual circle so that the angle between the first portion is θ, and a second line segment is drawn from the origin to the opposite side of the virtual circle so that the angle between the second portion is θ, and the angle between the first line segment and the second line segment is defined as an angle range R, Either (i) or (ii) below is met A video display device characterized by: (i) The position detection direction of the position detection means is included in the angle range R. (ii) The position detection direction of the position detection means is not included in the angle range R, and the angle formed by the position detection direction and the gaze detection direction, which is the direction in which the second light receiving unit of the gaze detection means is pointed, is greater than the directional angle. [Configuration 2] In the optical unit, when the user wears the image display device, the side closer to the user's nose is defined as the inside, and the side farther from the user's nose is defined as the outside. In the projection drawing, the first light-emitting unit of the position detecting means is disposed outside a vertical line passing through the optical axis, and the second light-receiving unit of the line-of-sight detecting means is disposed below a horizontal line passing through the optical axis. 2. The image display device according to configuration 1, [Configuration 3] A plurality of the gaze detection means is provided. 3. The image display device according to configuration 1 or 2. [Configuration 4] In the projection, the first light emitting unit of the position detecting means is disposed so as to irradiate the second infrared light vertically upward. 4. The image display device according to any one of configurations 1 to 3. [Configuration 5] When a plane perpendicular to the optical axis direction and on which the first light-emitting unit of the position detecting means is arranged is defined as a position detection plane, and a plane perpendicular to the optical axis direction and on which the second light-receiving unit of the line-of-sight detecting means is arranged is defined as a line-of-sight detection plane, When the user wears the image display device, the line-of-sight detection plane and the position detection plane are arranged in this order between the display unit of the optical unit and the user's eyes, as viewed from the display unit. 5. The image display device according to configuration 4. [Configuration 6] In the projection view, the distance from the first light-emitting unit of the position detecting means to the optical axis is greater than the distance from the second light-receiving unit of the line-of-sight detecting means to the optical axis. 6. The image display device according to any one of configurations 1 to 5. [Explanation of symbols]

[0057] 10: Display panel, 11: Driven lens, 13: Optical axis, 15: Position detection means, 16: Line-of-sight camera, 18: Motor, 20: Optical unit, 32: LED, 34: Photodiode

Claims

1. A head-mounted image display device, an optical unit having a display unit and an optical element; a driving means for driving at least one of the display unit and the optical element; a position detection means having a first light-emitting unit that irradiates a first infrared light and a first light-receiving unit that receives the first infrared light irradiated from the first light-emitting unit, and that detects a position of the driving means; a gaze detection unit that includes a second light-emitting unit that emits second infrared light and a second light-receiving unit that captures the second infrared light that is emitted from the second light-emitting unit and reflected by the user's eye, and that detects the gaze of the user; Equipped with a direction in which the first light-emitting unit of the position detection means is pointed is defined as a position detection direction, and a range of an angle θ (θ<90°) from the position detection direction is defined as a directivity angle; In a projection diagram in which the position detection means and the line of sight detection means are projected onto a plane perpendicular to the optical axis direction of the optical unit, when a position where a virtual circle having a radius equal to the distance from the optical axis to the first light-emitting unit overlaps with the first light-emitting unit is defined as the origin of the first infrared light, and a tangent to the virtual circle at the origin is divided into a first portion and a second portion with the origin as the boundary, a first line segment is drawn from the origin to the opposite side of the virtual circle so that the angle between the first portion is θ, and a second line segment is drawn from the origin to the opposite side of the virtual circle so that the angle between the second portion is θ, and the angle between the first line segment and the second line segment is defined as an angle range R, The following (i) or (ii) is satisfied: (i) the position detection direction of the position detection means is included in the angle range R (ii) The position detection direction of the position detection means is not included in the angle range R, and the angle formed by the position detection direction and the line-of-sight detection direction, which is the direction in which the second light receiving unit of the line-of-sight detection means is pointed, is larger than the directivity angle. A video display device characterized by:

2. In the optical unit, when the user wears the image display device, the side closer to the user's nose is defined as the inside, and the side farther from the user's nose is defined as the outside. In the projection drawing, the first light-emitting unit of the position detecting means is disposed outside a vertical line passing through the optical axis, and the second light-receiving unit of the line-of-sight detecting means is disposed below a horizontal line passing through the optical axis.

2. The image display device according to claim 1.

3. A plurality of the gaze detection means is provided.

3. The image display device according to claim 1 or 2.

4. In the projection view, the first light emitting unit of the position detecting means is disposed so as to irradiate the second infrared light vertically upward.

3. The image display device according to claim 1 or 2.

5. When a plane perpendicular to the optical axis direction and on which the first light-emitting unit of the position detecting means is arranged is defined as a position detection plane, and a plane perpendicular to the optical axis direction and on which the second light-receiving unit of the line-of-sight detecting means is arranged is defined as a line-of-sight detection plane, When the user wears the image display device, the line-of-sight detection plane and the position detection plane are arranged in this order between the display unit of the optical unit and the user's eyes, as viewed from the display unit.

5. The image display device according to claim 4.

6. In the projection view, the distance from the first light-emitting unit of the position detecting means to the optical axis is greater than the distance from the second light-receiving unit of the line-of-sight detecting means to the optical axis.

3. The image display device according to claim 1 or 2.

Images