Eye information detection device and eye information detection system

Abstract

The present invention improves line-of-sight detection accuracy. This eye information detection device includes: an optical system comprising a first semi-transmissive reflection unit that transmits at least a portion of incident light and reflects another portion of the incident light, a second semi-transmissive reflection unit that reflects one of linearly polarized incident light beams having polarization directions differing by approximately 90 degrees and transmits the other of the linearly polarized incident light beams, a lens disposed between the first semi-transmissive reflection unit and the second semi-transmissive reflection unit, and a polarization state change unit that changes the polarization state of the incident light between linearly polarized light and circularly polarized light, wherein image light based on an image from an image display unit for displaying the image is incident on the side of the first semi-transmissive reflection unit and simultaneously guided to an eyeball of a user by the optical system; a light source unit that emits invisible light to the eyeball; an imaging unit that acquires reflected light, reflected from the eyeball, of the emitted light of the invisible light from the light source unit and generates imaging data; and a polarization state adjustment unit that adjusts the polarization state of the light based on the emitted light.

Description

Eye information detection device and eye information detection system

[0001] The present disclosure relates to an eye information detection device and an eye information detection system.

[0002] In VR (Virtual Reality), AR (Augmented Reality), etc., a system that detects the user's line of sight and applies it to a user interface (UI) or the like is used. For example, in a display device such as a head-mounted display (HMD) worn by a user, a device having a function of detecting the user's line of sight has been proposed (see, for example, Patent Document 1).

[0003] This device includes a light source that irradiates infrared light onto the eyeball and an imaging device that acquires reflected light from the eyeball and generates an image, and estimates the line of sight based on the generated image of the eyeball. Specifically, this device estimates the orientation of the eyeball from the positional relationship between the pupil and the corneal reflex (Purkinje image) in the image.

[0004] In such a device, bright spots other than the Purkinje image (for example, reflected light from glasses worn by the user or sunlight reflection) become a problem. This is to reduce the line-of-sight detection accuracy. Such bright spots are referred to as outliers. In the above-described device, polarized infrared light is irradiated onto the eyeball, and three-direction polarized images are generated to remove outliers.

[0005] International Publication No. 2017 / 014137

[0006] However, in the above prior art, an imaging element that simultaneously generates a plurality of polarized images is required, and the effective resolution is reduced. For this reason, there is a problem that the line-of-sight detection accuracy is reduced.

[0007] Therefore, the present disclosure proposes an eye information detection device and an eye information detection system with improved line-of-sight detection accuracy.

[0008] This disclosure provides an eye information detection device comprising: a first semi-transparent reflecting section that transmits at least a portion of incident light and reflects the other portion; a second semi-transparent reflecting section that reflects one side of linearly polarized incident light with polarization directions approximately 90 degrees different and transmits the other; a lens disposed between the first semi-transparent reflecting section and the second semi-transparent reflecting section; and a polarization state changing section that mutually changes the polarization state of the incident light between linearly polarized and circularly polarized light. The device also includes an optical system that receives image light from an image display section that displays an image on the side of the first semi-transparent reflecting section and guides the image light to the user's eyeball; a light source section that emits invisible light to the eyeball; an imaging section that acquires reflected light from the invisible light emitted from the light source section and generates imaging data; and a polarization state adjustment section that adjusts the polarization state of the light based on the emitted light.

[0009] This figure shows an example of gaze detection according to the first embodiment of this disclosure. This figure shows an example of gaze detection according to the first embodiment of this disclosure. This figure shows an example of gaze detection according to the first embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection system according to the first embodiment of this disclosure. This figure shows an example of the configuration of an optical system according to the first embodiment of this disclosure. This figure shows an example of the optical path of an optical system according to the first embodiment of this disclosure. This figure shows an example of unwanted light according to the first embodiment of this disclosure. This figure shows an example of unwanted light according to the first embodiment of this disclosure. This figure shows an example of unwanted light according to the first embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the first embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the first embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the first embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the second embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the third embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the fourth embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the fifth embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the sixth embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the sixth embodiment of this disclosure. This figure shows an example of the configuration of an eye information detection device according to the seventh embodiment of this disclosure. This figure shows an example configuration of an eye information detection device according to the eighth embodiment of this disclosure. This figure shows an example configuration of an eye information detection device according to the ninth embodiment of this disclosure. This figure shows an example configuration of an eye information detection device according to the tenth embodiment of this disclosure. This figure shows an example configuration of an eye information detection device according to the tenth embodiment of this disclosure. This figure shows an example of the processing procedure for eye information detection according to the tenth embodiment of this disclosure. This figure shows an example configuration of an eye information detection device according to the eleventh embodiment of this disclosure.

[0010] Embodiments of the present disclosure will be described in detail below with reference to the drawings. The description will be in the following order. In each of the following embodiments, the same parts will be denoted by the same reference numerals, and redundant descriptions will be omitted. 1. First Embodiment 2. Second Embodiment 3. Third Embodiment 4. Fourth Embodiment 5. Fifth Embodiment 6. Sixth Embodiment 7. Seventh Embodiment 8. Eighth Embodiment 9. Ninth Embodiment 10. Tenth Embodiment 11. Eleventh Embodiment

[0011] (1. First Embodiment) <Configuration of Eye Information Detection System> <Gaze Detection> Figure 1A-1C is a diagram showing an example of gaze detection according to the first embodiment of the present disclosure. Figure 1A-1C is a diagram illustrating gaze detection in the display device of the present disclosure.

[0012] Figure 1A is a diagram illustrating an example of a gaze detection system. The left side of the figure shows a cross-section of an eyeball 200. The eyeball 200 comprises a spherical sclera 201, cornea 202, and iris 203. The right side of the figure shows a light source unit 130 that irradiates the eyeball 200 with infrared light and an imaging unit 140 that acquires reflected light and generates imaging data. The light source unit 130 and the imaging unit 140 are arranged in a frame 19. The figure shows an example in which four light source units 130 are arranged. The image display unit (image display unit 110, described later) that projects an image onto the eyeball is located on the right side of the frame 19 in the figure.

[0013] Figure 1B is a frontal view of the eyeball 200. The image of the eyeball 200 includes the iris 203 and pupil 204 located behind the cornea 202. The image also includes a Purkinje image 210 generated by the light source 130. The number of Purkinje images 210 is determined according to the number of light sources 130. Based on the positions of the iris 203, pupil 204, and Purkinje image 210, the line of sight can be detected.

[0014] Figure 1C shows an example of gaze detection. The leftmost part of the figure shows the iris 203, pupil 204, and Purkinje image 210 in the case of right rotation. The center of the figure shows the iris 203, etc., when the gaze is directed towards the center. The rightmost part of the figure shows the iris 203, etc., in the case of left rotation. In this way, the position and shape of the iris 203, pupil 204, and Purkinje image 210 change according to the orientation of the eyeball 200. Therefore, the orientation of the eyeball can be estimated from the position and shape of the iris 203, pupil 204, and Purkinje image 210. For example, gaze can be detected using a polynomial fitting method for pupil-corneal reflex or a model estimation method for pupil-corneal reflex.

[0015] Figure 2 is a diagram showing an example configuration of an eye information detection system according to the first embodiment of this disclosure. The figure is a block diagram showing an example configuration of the eye information detection system 10. The eye information detection system 10 is attached to an HMD or the like to detect the user's gaze. The figure further shows the user's eyeballs 200. The eye information detection system 10 comprises an image display unit 110, an optical system 120, a light source unit 130, an imaging unit 140, a polarization state adjustment unit 150, a control unit 181, a gaze detection unit 182, and an iris authentication unit 183. The optical system 120, light source unit 130, imaging unit 140, polarization state adjustment unit 150, control unit 181, gaze detection unit 182, and iris authentication unit 183, other than the image display unit 110, constitute an eye information detection device 100.

[0016] The image display unit 110 displays an image for the user to observe. This image display unit 110 displays an image based on an image signal input from an external source. The image display unit 110 can be configured, for example, as an organic EL display device. The thick arrows in Figure 2 represent the image light, which is the light based on the display of the image display unit 110.

[0017] The optical system 120 guides the image from the image display unit 110 to the eyeball 200. Details of the configuration of the optical system 120 will be described later.

[0018] The light source unit 130 emits light for line-of-sight detection. This light source unit 130 can use a light source that emits invisible light such as infrared light. The white arrows in Figure 2 represent the infrared light emitted by the light source unit 130.

[0019] The imaging unit 140 acquires ambient light, including reflected light from the light source unit 130 that has been reflected by the eyeball 200, and performs imaging to generate imaging data. The imaging unit 140 can use an image sensor that captures infrared light. The imaging unit 140 outputs the generated imaging data to the gaze detection unit 182 or the iris authentication unit 183.

[0020] The polarization state adjustment unit 150 adjusts the polarization state of the light based on the light emitted from the light source unit 130. This polarization state adjustment unit 150 adjusts the polarization state of the light emitted from the light source unit 130 and the reflected light reflected by the eyeball 200. The reflected light includes the reflected light from the light emitted by the glasses worn by the user. When this reflected light from the glasses is reflected by the optical system 120, multiple reflections may occur, where the light is reflected repeatedly between the glasses and the optical system. When such reflected light enters the imaging unit 140, the aforementioned outlier occurs. The polarization state adjustment unit 150 adjusts the polarization state of this light and reduces multiple reflections. Details of the configuration of the polarization state adjustment unit 150 will be described later.

[0021] The control unit 181 controls the entire eye information detection device 100. The control unit 181 also outputs control signals to the imaging unit 140.

[0022] The gaze detection unit 182 detects the gaze based on the imaging data from the imaging unit 140. The gaze detection unit 182 outputs the gaze detection result to an external device. The known methods described above can be applied to detect the gaze.

[0023] The iris authentication unit 183 performs iris authentication based on imaging data from the imaging unit 140. The iris authentication unit 183 outputs the authentication result to an external device. Known methods can be applied to iris authentication.

[0024] <Optical System Configuration> Figure 3 is a diagram showing an example of the configuration of an optical system according to the first embodiment of the present disclosure. The same figure is a cross-sectional view showing an example of the configuration of the optical system 120. The optical system 120 comprises two lenses 124 and 126 and a glass plate 121. A polarizer 122 and a polarization state changing unit 123 are arranged on the glass plate 121. A first semi-transparent reflecting unit 125 is arranged on lens 124. A polarization state changing unit 127 and a second semi-transparent reflecting unit 128 are arranged on lens 126.

[0025] The polarizer 122 transmits light in a predetermined polarization direction. The polarization state changing unit 123 and the polarization state changing unit 127 change the polarization state of the incident light between linear polarization and circular polarization. For example, a quarter polarizer can be used for the polarization state changing unit 123 and the polarization state changing unit 127. The first semi-transparent reflecting unit 125 transmits at least a portion of the incident light and reflects the other portion. For example, a half mirror can be used for the first semi-transparent reflecting unit 125. The second semi-transparent reflecting unit 128 reflects one portion of incident linearly polarized light with polarization directions that differ by approximately 90 degrees and transmits the other portion. For example, a reflective polarizer can be applied to the second semi-transparent reflecting unit 128.

[0026] The arrows in Figure 3 represent the trajectory of the image light from the image display unit 110 to the eyeball 200. As shown in Figure 3, the image light follows a trajectory that is folded back between the second semi-transparent reflecting unit 128 and the first semi-transparent reflecting unit 125. At this folding point, the incident light passes through the lens 124 twice. Such an optical system 120 is called a "pancake optical system".

[0027] Figure 4 is a diagram showing an example of the optical path of an optical system according to the first embodiment of the present disclosure. The diagram shows the polarization of incident light in the optical path from the image display unit 110 to the eyeball 200. The diagram shows a polarizer 122, a polarization state changing unit 123, a first semi-transparent reflecting unit 125, a polarization state changing unit 127, and a second semi-transparent reflecting unit 128 included in the optical system 120. The white arrows in the diagram represent the optical path of the incident light.

[0028] Light emitted from the image display unit 110 enters the polarizer 122 in an unpolarized state. This incident light is converted into linearly polarized light by the polarizer 122. Next, the incident light enters the polarization state changing unit 123. This polarization state changing unit 123 converts the incident light into circularly polarized light. This incident light passes through the first semi-transparent reflecting unit 125 and enters the polarization state changing unit 127. The polarization state changing unit 127 converts the incident light into linearly polarized light, and it enters the second semi-transparent reflecting unit 128. The second semi-transparent reflecting unit 128 reflects the incident light, and the polarization state changing unit 127 converts it into circularly polarized light. At this time, it is converted into circularly polarized light in a different direction than when it was transmitted previously. This incident light is reflected by the first semi-transparent reflecting unit 125 and enters the polarization state changing unit 127 again. This converted incident light is converted back into linearly polarized light by the polarization state changing unit 127. At this point, the light is converted to linear polarization in a direction approximately 90 degrees different from that of the previous transmission. The incident light with this polarization direction passes through the second semi-transparent reflecting section 128 and reaches the eyeball 200.

[0029] <Unwanted Light> Figures 5A-5C show an example of unwanted light according to the first embodiment of this disclosure. Figure 5A shows reflected light from invisible light from the light source 130 reflected by the glasses 300. This reflected light is referred to as primary reflected light.

[0030] Figure 5B shows the reflected light that is reflected again by the spectacle 300 after the primary reflected light is reflected at the interface of the optical system 120. This reflected light is called secondary reflected light.

[0031] Figure 5C shows the reflected light that is reflected again by the eyeglasses 300 after the primary reflected light has been reflected inside the optical system 120. This reflected light is called the third-order reflected light. Because the optical system 120 includes a first semi-transparent reflecting section 125 and a second semi-transparent reflecting section 128, it generates more third-order reflected light compared to an optical system composed of a single lens. When the third-order reflected light is captured by the imaging unit 140, the image contains many outliers, which reduces the accuracy of gaze detection.

[0032] <Basic Configuration of Eye Information Detection Device> Figure 6 is a diagram showing an example configuration of an eye information detection device according to the first embodiment of this disclosure. The same figure shows the configuration of the eye information detection device 100 when the polarization state adjustment unit 150 is not included, and is a diagram showing a comparative example. The eye information detection device 100 in the same figure includes an optical system 120, a light source unit 130, and an imaging unit 140. The same figure also shows an image display unit 110.

[0033] Unpolarized light 310 is emitted from the light source 130. This emitted light 310 is reflected by the glasses 300 to produce reflected light 311. When this reflected light 311 is incident on the second semi-transparent reflecting part 128, a portion is reflected according to the polarization direction, and another portion is transmitted through the second semi-transparent reflecting part 128. The reflected light 312 reflected by the second semi-transparent reflecting part 128 becomes the second reflected light. On the other hand, the reflected light 313 that has been transmitted through the second semi-transparent reflecting part 128 reaches the first semi-transparent reflecting part 125, where a portion is reflected and another portion is transmitted. The reflected light 314 reflected by the first semi-transparent reflecting part 125 is transmitted through the second semi-transparent reflecting part 128 and emitted as reflected light (reflected light 319) from the optical system 120. This reflected light 319 becomes the third reflected light. On the other hand, the reflected light that has passed through the first semi-transparent reflecting section 125 is emitted from the optical system 120. The second reflected light has approximately 50% of the light intensity of the reflected light 311. Similarly, the third reflected light has approximately 25% of the light intensity.

[0034] The above-mentioned light intensity was calculated assuming that the transmittance of the first semi-transparent reflecting section 125 to infrared light is 50%, the second semi-transparent reflecting section 128 is capable of completely separating linearly polarized infrared light, and the polarization state changing sections 123 and 127 do not act on infrared light. If each component has characteristics different from these assumptions, the light intensity of the second reflected light and the third reflected light will be different values.

[0035] <Configuration of the eye information detection device> Figure 7 is a diagram showing an example of the configuration of an eye information detection device according to the first embodiment of the present disclosure. The diagram shows the configuration of the eye information detection device 100 including the polarization state adjustment unit 150. The diagram shows an example in which the light source unit 130 is arranged in an area other than between the optical system 120 and the image display unit 110.

[0036] The polarization state adjustment unit 150 in Figure 7 is composed of an invisible light polarizer 151. This invisible light polarizer 151 is a polarizer that transmits invisible light in a predetermined polarization direction. The invisible light polarizer 151 is positioned between the light source unit 130 and the eyeball 200. The invisible light polarizer 151 adjusts the polarization state by transmitting the emitted light from the light source unit 130 in a polarization direction that is reflected by the second semi-transparent reflecting unit 128.

[0037] As shown in Figure 7, the reflected light 311 based on the outgoing light 310 that has passed through the invisible light polarizer 151 is completely reflected by the second semi-transparent reflector 128 to become reflected light 312. Since the reflected light does not penetrate the inside of the optical system 120, a third reflected light (reflected light 319) is not generated.

[0038] Thus, the eye information detection device 100 of the first embodiment of this disclosure can reduce the generation of reflected light due to multiple reflections between the eyeglasses 300 and the optical system 120 by arranging a polarization state adjustment unit 150 to adjust the polarization state of the emitted light 310. This prevents a decrease in gaze detection accuracy.

[0039] (2. Second Embodiment) The eye information detection device 100 of the first embodiment described above used a polarization state adjustment unit 150 consisting of a non-visible light polarizer 151 located near the light source unit 130. In contrast, the eye information detection device 100 of the second embodiment of this disclosure differs from the first embodiment described above in that it uses a polarization state adjustment unit 150 consisting of a non-visible light polarizer 152 and a non-visible light polarization direction changing unit 153 located near the optical system 120.

[0040] <Configuration of the eye information detection device> Figure 8 is a diagram showing an example configuration of an eye information detection device according to the second embodiment of the present disclosure. This diagram, like Figure 7, shows an example configuration of the eye information detection device 100. The eye information detection device 100 in this figure differs from the eye information detection device 100 in Figure 7 in that it includes a polarization state adjustment unit 150 composed of a non-visible light polarizer 152 and a non-visible light polarization direction changing unit 153.

[0041] The non-visible light polarizer 152 is a polarizer that transmits the reflected light in the polarization direction that passes through the second semi-transmissive reflection part 128 of the reflected light 311. Also, the non-visible light polarization direction changing part 153 rotates the polarization direction of the reflected light transmitted through the non-visible light polarizer 152 by approximately 90 degrees. A 1 / 2 polarizing plate corresponding to infrared light can be used for the non-visible light polarization direction changing part 153. The non-visible light polarizer 152 and the non-visible light polarization direction changing part 153 are arranged between the eyeball 200 and the optical system 120. The polarization state adjusting part 150 in FIG. 8 adjusts the polarization state by transmitting the reflected light in the polarization direction reflected by the second semi-transmissive reflection part 128, which is light based on the emitted light 310.

[0042] As shown in FIG. 8, the reflected light 311 becomes the reflected light 320 in the polarization direction reflected by the second semi-transmissive reflection part 128 through the non-visible light polarizer 152 and the non-visible light polarization direction changing part 153. This reflected light 320 is all reflected by the second semi-transmissive reflection part 128 to become the reflected light 321, and then becomes the reflected light 312 through the non-visible light polarizer 152 and the non-visible light polarization direction changing part 153. Since the reflected light does not enter the interior of the optical system 120, the third reflected light (reflected light 319) is not generated.

[0043] Since the configuration of the eye information detection device 100 other than that described above is the same as the configuration of the eye information detection device 100 in the first embodiment of the present disclosure, the description thereof is omitted.

[0044] Thus, the eye information detection device 100 of the second embodiment of the present disclosure adjusts the polarization state of the emitted light 310 using the polarization state adjusting part 150 arranged near the optical system 120. Thereby, the generation of the reflected light due to multiple reflections between the glasses 300 and the optical system 120 can be reduced, and the decrease in the line-of-sight detection accuracy can be prevented.

[0045] (3. Third Embodiment) The eye information detection device 100 of the first embodiment described above used the polarization state adjustment unit 150 including the non-visible light polarizer 151 disposed near the light source unit 130. In contrast, the eye information detection device 100 of the third embodiment of the present disclosure is different from the first embodiment described above in that it uses the polarization state adjustment unit 150 configured by the non-visible light polarization state changing unit 154 disposed inside the optical system 120.

[0046] <Configuration of Eye Information Detection Device> FIG. 9 is a diagram showing a configuration example of an eye information detection device according to the third embodiment of the present disclosure. This figure is a diagram showing a configuration example of the eye information detection device 100, similar to FIG. 7. The eye information detection device 100 in this figure is different from the eye information detection device 100 in FIG. 7 in that it includes the polarization state adjustment unit 150 configured by the non-visible light polarization state changing unit 154.

[0047] The non-visible light polarization state changing unit 154 in FIG. 9 is disposed between the second semi-transmissive reflection unit 128 and the first semi-transmissive reflection unit 125. The polarization state adjustment unit 150 in FIG. 9 adjusts the polarization state by converting the reflected light 311 transmitted through the first semi-transmissive reflection unit 125 into circularly polarized light.

[0048] As shown in FIG. 9, part of the reflected light (reflected light 313) converted into circularly polarized light by the non-visible light polarization state changing unit 154 is reflected by the first semi-transmissive reflection unit 125 to become the reflected light 314. This reflected light 314 is converted by the non-visible light polarization state changing unit 154 into linearly polarized reflected light 315 and enters the second semi-transmissive reflection unit 128. This reflected light 315 travels back and forth between the second semi-transmissive reflection unit 128 and the first semi-transmissive reflection unit 125 (reflected light 316 to reflected light 318) and becomes the reflected light 319. Thus, the reflected light that has entered the optical system 120 is attenuated by the folded optical path.

[0049] The configuration of the eye information detection device 100 other than that described above is the same as the configuration of the eye information detection device 100 in the first embodiment of the present disclosure, and thus the description thereof is omitted.

[0050] Thus, the eye information detection device 100 of the third embodiment of this disclosure adjusts the polarization state of the emitted light 310 using a polarization state adjustment unit 150 located inside the optical system 120. This reduces the generation of reflected light due to multiple reflections between the eyeglasses 300 and the optical system 120, and prevents a decrease in gaze detection accuracy.

[0051] (4. Fourth Embodiment) The eye information detection device 100 of the third embodiment described above used a polarization state adjustment unit 150 consisting of a non-visible light polarization state changing unit 154. In contrast, the eye information detection device 100 of the fourth embodiment of this disclosure differs from the third embodiment described above in that it further comprises a non-visible light polarizer 151.

[0052] <Configuration of the eye information detection device> Figure 10 is a diagram showing an example configuration of an eye information detection device according to the fourth embodiment of the present disclosure. This diagram, like Figure 9, shows an example configuration of the eye information detection device 100. The eye information detection device 100 in this figure differs from the eye information detection device 100 in Figure 9 in that it includes a polarization state adjustment unit 150 composed of a non-visible light polarizer 151 and a non-visible light polarization state changing unit 154.

[0053] The invisible light polarization state changing unit 154 is positioned between the second semi-transparent reflecting unit 128 and the first semi-transparent reflecting unit 125, as in Figure 9. The invisible light polarizer 151 is positioned between the light source unit 130 and the eyeball 200.

[0054] As shown in Figure 10, the reflected light 311, based on the outgoing light 310 converted to linear polarization by the invisible light polarizer 151, is entirely transmitted through the second semi-transparent reflector 128. This transmitted reflected light is converted to circular polarization by the invisible light polarization state changer 154 to become reflected light 313, which then enters the first semi-transparent reflector 125. After that, it follows the same trajectory as reflected light 314 in Figure 9, becoming reflected light 319. In this way, no second reflected light is generated, and the reflected light that enters the interior of the optical system 120 is attenuated by the folded optical path.

[0055] The configuration of the eye information detection device 100 other than that described above is the same as that of the eye information detection device 100 in the third embodiment of this disclosure, so a description will be omitted.

[0056] As described above, the eye information detection device 100 of the fourth embodiment of this disclosure adjusts the polarization state of the emitted light 310 using a polarization state adjustment unit 150 which consists of a non-visible light polarizer 151 arranged near the light source unit 130 and a non-visible light polarization state changing unit 154 arranged in the optical system 120. This reduces the generation of reflected light due to reflection between the eyeglasses 300 and the optical system 120 and reflected light due to multiple reflections between the eyeglasses 300 and the optical system 120, thereby preventing a decrease in gaze detection accuracy.

[0057] (5. Fifth Embodiment) The eye information detection device 100 of the first embodiment described above used an imaging unit 140 located near the optical system 120. In contrast, the eye information detection device 100 of the fifth embodiment of this disclosure differs from the first embodiment described above in that it uses an imaging unit 140 located between the optical system 120 and the image display unit 110.

[0058] <Configuration of the eye information detection device> Figure 11 is a diagram showing an example configuration of an eye information detection device according to the fifth embodiment of the present disclosure. This figure, like Figure 7, shows an example configuration of the eye information detection device 100. An eyeball 200 is shown in this figure. The eye information detection device 100 in this figure differs from the eye information detection device 100 in Figure 7 in that the imaging unit 140 is positioned between the optical system 120 and the image display unit 110.

[0059] The polarization state adjustment unit 150 in Figure 11 is composed of the invisible light polarization direction changing unit 153 described in Figure 8. The invisible light polarization direction changing unit 153 in Figure 11 is positioned between the first semi-transparent reflecting unit 125 and the second semi-transparent reflecting unit 128. The polarization state adjustment unit 150 in Figure 11 adjusts the polarization state by changing the polarization direction of the light that has passed through the second semi-transparent reflecting unit 128, which is reflected light 320 based on the emitted light 310. Specifically, the polarization state adjustment unit 150 in Figure 11 adjusts the polarization state by changing the polarization direction of the light that has been further reflected by the first semi-transparent reflecting unit 125, which is reflected light that has passed through the second semi-transparent reflecting unit 128, to the polarization direction that passes through the second semi-transparent reflecting unit 128.

[0060] The reflected light 320, which is emitted from the light source 130 and reflected by the eyeball, partially passes through the second semi-transparent reflector 128, where its polarization direction is changed by the invisible light polarization direction changing unit 153 to become reflected light 323, which then enters the first semi-transparent reflector 125. A portion of this reflected light 323 passes through the first semi-transparent reflector 125 and reaches the imaging unit 140. Another portion of the reflected light 323 is reflected by the first semi-transparent reflector 125 to become reflected light 324, which then passes through the invisible light polarization direction changing unit 153 and the second semi-transparent reflector 128 to become reflected light 325. This reflected light is reflected by the eyeglasses 300 (not shown) to become reflected light 326, which then enters the optical system 120. This incident light is attenuated as it passes through the optical system 120. In this way, the third reflected light is attenuated. Furthermore, since the reflection of the reflected light 324 at the second semi-transparent reflecting portion 128 is reduced, it is possible to prevent the generation of stray light directed toward the imaging portion 140.

[0061] The configuration of the eye information detection device 100 other than that described above is the same as that of the eye information detection device 100 in the first embodiment of this disclosure, so a description will be omitted.

[0062] Thus, in the eye information detection device 100 of the fifth embodiment of this disclosure, even when the imaging unit 140 is positioned between the optical system 120 and the image display unit 110, the polarization state adjustment unit 150 can reduce reflected light due to reflection between the eyeglasses 300 and the optical system 120. This prevents a decrease in gaze detection accuracy.

[0063] (6. Sixth Embodiment) The eye information detection device 100 of the fifth embodiment described above used an imaging unit 140 positioned between the optical system 120 and the image display unit 110. In contrast, the eye information detection device 100 of the sixth embodiment of this disclosure differs from the fifth embodiment described above in that it diffracts the incident light to the imaging unit 140 using a diffracting element.

[0064] <Configuration of the eye information detection device> Figures 12A and 12B are diagrams showing an example configuration of an eye information detection device according to the sixth embodiment of the present disclosure. Figures 12A and 12B are diagrams illustrating the outline of the eye information detection device 100 according to the sixth embodiment of the present disclosure. The eye information detection device 100 in Figures 12A and 12B further comprises a polarization state changing unit 157, a diffraction element 156, a non-visible light polarization state changing unit 154, and a non-visible light polarizer 152. The polarization state changing unit 157, the diffraction element 156, the non-visible light polarization state changing unit 154, and the non-visible light polarizer 152 are arranged between the optical system 120 and the image display unit 110. The diffraction element 156 diffracts incident light in a direction corresponding to the rotation direction of circularly polarized light.

[0065] In Figure 12A, the arrows represent the trajectory of the image light from the image display unit 110. The image light can be represented by a superposition of left-handed circularly polarized light and right-handed circularly polarized light. This light is separated into left-handed and right-handed circularly polarized light by the diffraction element 156 and diffracted in different directions. These lights are then converted into two types of linearly polarized light perpendicular to each other by the polarization state changing unit 157 and incident on the optical system 120. One of these incident lights is cut off by the polarizer 122 of the optical system 120, and only the light in the required diffraction direction is propagated to the eyeball 200.

[0066] In Figure 12B, the arrows represent the trajectory of reflected light emitted from the light source 130 and reflected by the eyeball 200. The reflected light that has passed through the optical system 120 becomes circularly polarized light due to the action of the polarization state changing unit 157. At this time, due to the difference in wavelength, it contains both left-handed and right-handed circularly polarized light, and the optical path is separated by the diffraction element 156. One of these paths passes through the invisible light polarization state changing unit 154 and the invisible light polarizer 152 and is incident on the imaging unit 140. The other light separated by the diffraction element 156 is converted into linearly polarized light by the invisible light polarization state changing unit 154 and then cut off by the invisible light polarizer 152. In this way, by arranging the invisible light polarization state changing unit 154, one of the two optical paths generated by the diffraction element 156 can be eliminated.

[0067] Figure 13 is a diagram showing an example configuration of an eye information detection device according to the sixth embodiment of the present disclosure. This figure, like Figure 11, shows an example configuration of the eye information detection device 100. The eye information detection device 100 in this figure differs from the eye information detection device 100 in Figure 11 in that it comprises a polarization state changing unit 157, a diffraction element 156, a non-visible light polarization state changing unit 154, and a non-visible light polarizer 152.

[0068] Of the reflected light 320, the reflected light 331 that has passed through the optical system 120 and been converted to circular polarization by the polarization state changing unit 157 is diffracted by the diffraction element 156 and split into two lights with different rotation directions. Subsequently, it is polarized to linear polarization by the invisible light polarization state changing unit 154, and one of them is cut off by the invisible light polarizer 152.

[0069] The reflected light 326 from the glasses 300 also passes through the optical system 120 and becomes reflected light 332, which is similarly split into two by the diffraction element 156. One of these is cut off by the invisible light polarizer 152. As a result, secondary reflected light incident on the imaging unit 140 can be reduced.

[0070] The configuration of the eye information detection device 100 other than that described above is the same as that of the eye information detection device 100 in the fifth embodiment of this disclosure, so a description will be omitted.

[0071] Thus, the eye information detection device 100 of the fifth embodiment of this disclosure can reduce the reflected light incident on the imaging unit 140 by separating the reflected light into two using the diffraction element 156 and cutting one of them. This prevents a decrease in the accuracy of gaze detection.

[0072] (7. Seventh Embodiment) The eye information detection device 100 of the fifth embodiment described above used a non-visible light polarization direction changing unit 153 arranged inside the optical system 120. In contrast, the eye information detection device 100 of the seventh embodiment of this disclosure differs from the fifth embodiment described above in that a plurality of polarization state changing units are arranged inside the optical system 120.

[0073] <Configuration of the eye information detection device> Figure 14 is a diagram showing an example configuration of the eye information detection device according to the seventh embodiment of this disclosure. The same figure shows an example configuration of the eye information detection device 100 according to the seventh embodiment of this disclosure.

[0074] The polarization state adjustment unit 150 in Figure 14 is composed of a non-visible light polarization state changing unit 154 and a polarization state changing unit 167. This polarization state changing unit 167 is positioned in place of the polarization state changing unit 127 of the optical system 120, and changes the polarization state of visible and non-visible light between linear polarization and circular polarization. The polarization state adjustment unit 150 in Figure 14 adjusts the polarization state by changing the polarization direction of the light reflected by the first semi-transparent reflecting unit 125 to the polarization direction that passes through the second semi-transparent reflecting unit 128.

[0075] Furthermore, the eye information detection device 100 in Figure 14 further comprises a non-visible light polarizer 152, a polarization state changing unit 168, and a polarization state changing unit 169. The non-visible light polarizer 152 is positioned between the eyeball 200 and the optical system 120, similar to the eye information detection device 100 in Figure 8. The polarization state changing units 168 and 169 change the polarization state of visible and non-visible light between linear polarization and circular polarization. The polarization state changing unit 168 is positioned in place of the polarization state changing unit 123 of the optical system 120. The polarization state changing unit 169 is positioned between the optical system 120 and the imaging unit 140. Quarter polarizers corresponding to visible light and infrared light can be used for the polarization state changing units 167, 168, and 169.

[0076] Of the reflected light 320, the reflected light that has passed through the invisible light polarizer 152 and the second semi-transparent reflector 128 is converted to circular polarization by the invisible light polarization state changing unit 154, and then converted to linearly polarized reflected light 323 by the polarization state changing unit 167. A portion of this reflected light 323 passes through the first semi-transparent reflector 125, is converted back to circular polarization by the polarization state changing unit 168, is converted to linear polarization by the polarizer 122, passes through the polarization state changing unit 169, and enters the imaging unit 140.

[0077] On the other hand, the reflected light 324 of the reflected light 323 reflected by the first semi-transparent reflecting part 125 is changed to circular polarization by the polarization state changing part 167, and then changed to linear polarization by the invisible light polarization state changing part 154 before passing through the second semi-transparent reflecting part 128. This reflected light is cut off by the invisible light polarizer 152. In this way, since the reflected light does not shine on the glasses 300 (not shown), multiple reflected light is reduced. In addition, since the reflection of the reflected light 324 at the second semi-transparent reflecting part 128 is reduced, the generation of stray light directed toward the imaging unit 140 can be prevented.

[0078] The configuration of the eye information detection device 100 other than that described above is the same as that of the eye information detection device 100 in the fifth embodiment of this disclosure, so a description will be omitted.

[0079] Thus, in the eye information detection device 100 of the seventh embodiment of this disclosure, even when the imaging unit 140 is positioned between the optical system 120 and the image display unit 110, the polarization state adjustment unit 150 can reduce reflected light due to reflection between the eyeglasses 300 and the optical system 120. This prevents a decrease in gaze detection accuracy.

[0080] (8. Eighth Embodiment) The eye information detection device 100 of the seventh embodiment described above used a polarization state adjustment unit 150 composed of a non-visible light polarization state changing unit 154 and a polarization state changing unit 167. In contrast, the eye information detection device 100 of the eighth embodiment of the present disclosure differs from the seventh embodiment described above in that it further includes a diffraction element 156.

[0081] <Configuration of the eye information detection device> Figure 15 is a diagram showing an example configuration of an eye information detection device according to the eighth embodiment of this disclosure. This diagram, like Figure 14, shows an example configuration of the eye information detection device 100. It differs from the eye information detection device 100 of Figure 14 in that it further includes a diffraction element 156.

[0082] The imaging unit 140 in Figure 15 acquires the reflected light that has passed through the polarization state changing unit 169 and the diffraction element 156 of the reflected light 320, and generates imaging data. The diffraction element 156 in Figure 15 splits the optical path of the reflected light, which has been changed to circular polarization by the polarization state changing unit 169, into two. However, due to the action of the polarization state changing unit 169, only circularly polarized light in one direction is incident, so diffraction occurs in only one direction. This reduces the generation of stray light. The polarization state changing unit 169 is an example of a "visible light / invisible light polarization state changing unit" in this disclosure.

[0083] The configuration of the eye information detection device 100 other than that described above is the same as that of the eye information detection device 100 in the seventh embodiment of this disclosure, so a description will be omitted.

[0084] Thus, the eye information detection device 100 of the eighth embodiment of this disclosure can reduce the generation of stray light by arranging the polarization state changing unit 169 and the diffraction element 156.

[0085] (9. Ninth Embodiment) In the eye information detection device 100 of the first embodiment described above, the light source unit 130 was located outside the optical system 120. In contrast, the eye information detection device 100 of the ninth embodiment of this disclosure differs from the first embodiment described above in that the light source unit 130 is located between the optical system 120 and the image display unit 110.

[0086] <Configuration of the eye information detection device> Figure 16 is a diagram showing an example configuration of an eye information detection device according to the ninth embodiment of the present disclosure. This diagram, like Figure 7, shows an example configuration of the eye information detection device 100. The eye information detection device 100 in this figure differs from the eye information detection device 100 in Figure 7 in that the light source unit 130 is arranged between the optical system 120 and the image display unit 110.

[0087] The polarization state adjustment unit 150 in Figure 16 is composed of a non-visible light polarization state changing unit 154. This non-visible light polarization state changing unit 154 is positioned between the eyeball 200 and the optical system 120. The polarization state adjustment unit 150 in Figure 16 adjusts the polarization state by converting the emitted light 310 into circularly polarized emitted light and converting the reflected light 320, which is reflected by the eyeball 200 from the emitted light 310, into linearly polarized light in the polarization direction reflected by the second semi-transparent reflecting unit 128.

[0088] Of the light 310 emitted from the light source unit 130, the emitted light in the polarization direction that passes through the polarizer 122 passes through the optical system 120 and is converted into circularly polarized emitted light 327 by the invisible light polarization state conversion unit 154 and irradiated onto the eyeball 200 (not shown). The circularly polarized reflected light 320 from the eyeball 200 is converted into linearly polarized light by the invisible light polarization state conversion unit 154 and incident on the second semi-transparent reflecting unit 128. This incident light is completely reflected by the second semi-transparent reflecting unit 128 and converted into circularly polarized reflected light 328 by the invisible light polarization state conversion unit 154 and irradiated onto the eyeglasses 300. In this way, since multiple reflections do not occur, unwanted light can be reduced.

[0089] The configuration of the eye information detection device 100 other than that described above is the same as that of the eye information detection device 100 in the first embodiment of this disclosure, so a description will be omitted.

[0090] Thus, in the ninth embodiment of the present disclosure, the eye information detection device 100 adjusts the polarization state of the emitted light 310 using the polarization state adjustment unit 150, even when the light source unit 130 is positioned between the optical system 120 and the image display unit 110. This reduces the generation of reflected light due to multiple reflections between the eyeglasses 300 and the optical system 120, and prevents a decrease in gaze detection accuracy.

[0091] (10. Tenth Embodiment) The eye information detection device 100 of the ninth embodiment described above used a light source unit 130 positioned between the optical system 120 and the image display unit 110. In contrast, the eye information detection device 100 of the tenth embodiment of this disclosure differs from the ninth embodiment described above in that an imaging unit 140 is further positioned between the optical system 120 and the image display unit 110.

[0092] <Configuration of the eye information detection device> Figure 17 is a diagram showing an example configuration of an eye information detection device according to the tenth embodiment of the present disclosure. The same figure shows an example configuration of an eye information detection device 100 according to the tenth embodiment of the present disclosure. The eye information detection device 100 in the same figure differs from the eye information detection device 100 of Figure 16 in that the imaging unit 140 is arranged between the optical system 120 and the image display unit 110, and an invisible light polarization state changing unit 158 ​​is used instead of an invisible light polarization state changing unit 154. This invisible light polarization state changing unit 158 ​​is an element that can switch between a mode that changes the polarization state of incident light and a mode that does not change the polarization state of incident light. For example, an active retarder can be used for this invisible light polarization state changing unit 158.

[0093] Figure 17 shows the case where the polarization control of the non-visible light polarization state changing unit 158 ​​is in the ON state, i.e., the mode in which the polarization state is changed.

[0094] Furthermore, the upper part of Figure 17 represents the case of Fresnel reflection. In this type of Fresnel reflection, polarization is maintained in both the incident and reflected light. Examples of Fresnel reflection include corneal reflection and reflection in eyeglasses 300.

[0095] In the upper eye information detection device 100 of Figure 17, the light 310 emitted from the light source unit 130 is converted to circularly polarized light 327, similar to Figure 16. The reflected light 320 is converted to linearly polarized light by the invisible light polarization state changing unit 158 ​​and reflected by the second semi-transparent reflecting unit 128. As a result, the reflected light 320 cannot penetrate into the optical system 120.

[0096] The lower part of Figure 17 illustrates the case of diffuse reflection. In this type of diffuse reflection, the polarization state of the incident light is not maintained, and the reflected light becomes unpolarized. Examples of this type of diffuse reflection include iris reflection and reflection by the skin.

[0097] In the lower eye information detection device 100 shown in Figure 17, unpolarized reflected light 320 passes through the invisible light polarization state changing unit 158 ​​and enters the second semi-transparent reflecting unit 128. A portion of this incident light passes through the second semi-transparent reflecting unit 128 and reaches the imaging unit 140.

[0098] Figure 18 shows an example of the configuration of an eye information detection device according to the tenth embodiment of the present disclosure. This figure shows the case when the polarization control of the invisible light polarization state changing unit 158 ​​is in the off state, i.e., in a mode in which the polarization state is not changed. The light 310 emitted from the light source unit 130 becomes linearly polarized light 327 and irradiates the eyeball 200. The linearly polarized reflected light 320 passes through the invisible light polarization state changing unit 158 ​​and the optical system 120 and reaches the imaging unit 140.

[0099] In this way, by switching the mode of the invisible light polarization state changing unit 158, it is possible to select the acquisition of the Fresnel reflection component. Switching the mode of the invisible light polarization state changing unit 158 ​​can be performed based on the control of the control unit 181. For example, when iris authentication is performed or when glasses 300 are worn, the invisible light polarization state changing unit 158 ​​is turned on to perform imaging with suppressed reflected light. Alternatively, during calibration, the invisible light polarization state changing unit 158 ​​can be turned off to estimate the corneal radius and the position of glasses 300 based on reflected light.

[0100] <Eye Information Detection Method> Figure 19 is a diagram showing an example of the processing procedure for eye information detection according to the tenth embodiment of the present disclosure. The same figure is a flowchart showing an example of the processing procedure by the control unit 181. First, the control unit 181 starts up the imaging unit 140 (step S101). Next, the control unit 181 turns off the polarization control of the invisible light polarization state changing unit 158 ​​(step S102). Next, the control unit 181 causes the gaze detection unit 182 to perform gaze detection processing (step S103). Next, the control unit 181 determines whether to perform iris authentication or glasses detection (step S104). If, as a result, iris authentication or glasses detection is to be performed (step S104, Yes), the control unit 181 turns on the polarization control of the invisible light polarization state changing unit 158 ​​(step S105) and proceeds to the processing in step S103. On the other hand, if iris recognition or glasses detection is not performed in step S104 (step S104, No), the control unit 181 proceeds to the process in step S102.

[0101] The configuration of the eye information detection device 100 other than that described above is the same as that of the eye information detection device 100 in the ninth embodiment of this disclosure, so a description will be omitted.

[0102] Thus, the eye information detection device 100 of the tenth embodiment of this disclosure uses an element that can switch between a mode that changes the polarization state of the incident light and a mode that does not change the polarization state of the incident light. This makes it possible to select the reflected light to be detected.

[0103] (11. Eleventh Embodiment) In the eye information detection device 100 of the first embodiment described above, the light source unit 130 was located outside the optical system 120. In contrast, the eye information detection device 100 of the eleventh embodiment of this disclosure differs from the first embodiment described above in that the light source unit 130 is located inside the optical system 120.

[0104] <Configuration of the eye information detection device> Figure 20 is a diagram showing an example configuration of an eye information detection device according to the eleventh embodiment of the present disclosure. This diagram, like Figure 7, shows an example configuration of the eye information detection device 100. The eye information detection device 100 in this figure differs from the eye information detection device 100 in Figure 7 in that the light source unit 130 is arranged between the second semi-transparent reflecting unit 128 and the polarization state changing unit 127. In addition, the polarization state adjustment unit 150 in this figure is composed of a non-visible light polarization direction changing unit 153.

[0105] The invisible light polarization direction changing unit 153 is located near the optical system 120 and changes the polarization direction of the light 310 emitted from the light source unit 130. The polarization state adjustment unit 150 in Figure 20 adjusts the polarization state by changing the polarization direction of the emitted light that has passed through the second semi-transparent reflecting unit 128.

[0106] Of the emitted light 310, the emitted light 327 that has passed through the second semi-transparent reflecting section 128 has its polarization direction changed by the invisible light polarization direction changing section 153 and is incident on the eyeball 200. The reflected light 312 from the eyeball 200 is incident on the second semi-transparent reflecting section 128 without passing through the invisible light polarization direction changing section 153. This reflected light 312 is completely reflected by the second semi-transparent reflecting section 128 and becomes reflected light 328. In this way, since the reflected light does not enter the inside of the optical system 120, a third reflected light is not generated.

[0107] The configuration of the eye information detection device 100 other than that described above is the same as that of the eye information detection device 100 in the first embodiment of this disclosure, so a description will be omitted.

[0108] Thus, in the eye information detection device 100 of the eleventh embodiment of this disclosure, even when the light source unit 130 is located inside the optical system 120, the polarization state of the emitted light 310 is adjusted using the polarization state adjustment unit 150. This reduces the generation of reflected light due to multiple reflections between the eyeglasses 300 and the optical system 120, and prevents a decrease in gaze detection accuracy.

[0109] In addition, in the eye information detection device 100 shown in Figures 7, 8, 9, and 10, the light source unit 130 can also be placed on the image display unit 110. Furthermore, in the eye information detection device 100 shown in Figures 11, 13, 14, and 15, a configuration in which a non-visible light polarization state changing unit 158 ​​is further added is also possible.

[0110] Furthermore, the effects described herein are merely illustrative and not limiting, and other effects may also occur.

[0111] Furthermore, this technology can also take the following configurations: (1) An eye information detection device comprising: a first semi-transparent reflecting part that transmits at least a portion of incident light and reflects the other portion; a second semi-transparent reflecting part that reflects one side of linearly polarized incident light with polarization directions differing by approximately 90 degrees and transmits the other side; a lens disposed between the first semi-transparent reflecting part and the second semi-transparent reflecting part; and a polarization state changing part that mutually changes the polarization state of the incident light between linearly polarized and circularly polarized light; an optical system into which image light from an image display unit that displays an image is incident on the side of the first semi-transparent reflecting part and guides said image light to the user's eyeball; a light source unit that emits invisible light to the eyeball; an imaging unit that acquires reflected light reflected by the eyeball from the invisible light emitted from the light source unit and generates imaging data; and a polarization state adjustment unit that adjusts the polarization state of light based on the emitted light. (2) The eye information detection device according to (1), wherein the light source unit is disposed in a region other than between the optical system and the image display unit. (3) The eye information detection device according to (2), wherein the polarization state adjustment unit is composed of an invisible light polarizer that transmits invisible light in a predetermined polarization direction and is placed between the light source and the eyeball, and the invisible light polarizer adjusts the polarization state by transmitting the emitted light in a polarization direction that is reflected at the second semi-transparent reflecting unit of the emitted light. (4) The eye information detection device according to (2), wherein the polarization state adjustment unit is composed of a polarizer that transmits the reflected light in a polarization direction that is transmitted at the second semi-transparent reflecting unit of the reflected light which is light based on the emitted light, and an invisible light polarization direction changing unit that rotates the polarization direction of the reflected light of invisible light that has been transmitted through the polarizer by approximately 90 degrees, the polarizer is placed between the eyeball and the optical system, and the invisible light polarization direction changing unit is placed between the polarizer and the optical system. (5) The eye information detection device according to (2), wherein the polarization state adjustment unit is composed of an invisible light polarization state changing unit which is arranged between the second semi-transparent reflecting unit and the first semi-transparent reflecting unit and changes the polarization state of the invisible light, and adjusts the polarization state by converting the reflected light, which is light based on the emitted light, into circularly polarized light.(6) The eye information detection device according to (5), wherein the polarization state adjustment unit is composed of an invisible light polarizer that transmits invisible light in a predetermined polarization direction and an invisible light polarization state changing unit, which are arranged between the eyeball and the optical system, and transmits the emitted light in a polarization direction that is reflected by the second semi-transparent reflecting unit of the emitted light, and converts the reflected light based on the emitted light into circularly polarized light. (7) The eye information detection device according to (2), wherein the imaging unit is arranged between the optical system and the image display unit. (8) The eye information detection device according to (7), wherein the polarization state adjustment unit is composed of an invisible light polarization direction changing unit that rotates the polarization direction of the reflected light, which is invisible light, by approximately 90 degrees, which are arranged between the second semi-transparent reflecting unit and the first semi-transparent reflecting unit, and adjusts the polarization state by changing the polarization direction of the light that has been transmitted through the second semi-transparent reflecting unit of the reflected light, which is light based on the emitted light. (9) The eye information detection device according to (8), further comprising a diffracting element disposed between the optical system and the imaging unit, an invisible light polarization state changing unit for changing the polarization state of invisible light, and an invisible light polarizer which transmits invisible light in a predetermined polarization direction, wherein the imaging unit acquires the reflected light diffracted by the diffracting element and transmitted through the invisible light polarization state changing unit and generates imaging data. (10) The eye information detection device according to (7), wherein the polarization state changing unit changes the polarization state of visible light and invisible light, and the polarization state adjustment unit is composed of the polarization state changing unit and the invisible light polarization state changing unit for changing the polarization state of invisible light, wherein the invisible light polarization state changing unit is disposed between the second semi-transparent reflecting unit and the polarization state changing unit. (11) The eye information detection device according to (10), further comprising a polarizer disposed between the eyeball and the optical system which transmits the reflected light in a polarization direction that transmits through the second semi-transparent reflecting unit, which is the reflected light based on the emitted light. (12) The eye information detection device according to (11), further comprising a visible light / invisible light polarization state changing unit and a diffraction element disposed between the polarizer and the imaging unit, wherein the imaging unit acquires the reflected light that has passed through the visible light / invisible light polarization state changing unit and the diffraction element and generates imaging data.(13) The eye information detection device according to (1), wherein the light source unit irradiates the eyeball with emitted light via the optical system, and the polarization state adjustment unit is composed of an invisible light polarization state changing unit that changes the polarization state of the invisible light, and the invisible light polarization state changing unit is positioned between the eyeball and the second semi-transparent reflecting unit and adjusts the polarization state by converting the emitted light into circularly polarized light and converting the reflected light reflected by the eyeball from the converted emitted light into linearly polarized light in the polarization direction reflected by the second semi-transparent reflecting unit. (14) The eye information detection device according to (1), wherein the light source unit irradiates the eyeball with emitted light via the optical system, and the optical system further comprises a polarizer that transmits incident light in a predetermined polarization direction and a polarization state changing unit that changes the polarization state of the incident light, positioned between the first semi-transparent reflecting unit and the image display unit. (15) The eye information detection device according to (14), wherein the polarization state adjustment unit is composed of an invisible light polarization state changing unit that changes the polarization state of the invisible light, and the invisible light polarization state changing unit is positioned between the eyeball and the second semi-transparent reflecting unit, and adjusts the polarization state by converting the emitted light into circular polarization and converting the reflected light reflected by the eyeball from the converted emitted light into linear polarization in the polarization direction reflected by the second semi-transparent reflecting unit. (16) The eye information detection device according to (15), wherein the invisible light polarization state changing unit has a mode for changing the polarization state of the invisible light and a mode for not changing the polarization state of the invisible light. (17) The eye information detection device according to (1), wherein the light source is positioned between the second semi-transparent reflecting unit and the polarization state changing unit, and the polarization state adjustment unit is composed of an invisible light polarization direction changing unit that rotates the polarization direction of the emitted light, which is invisible light, by approximately 90 degrees, positioned between the eyeball and the second semi-transparent reflecting unit, thereby adjusting the polarization state by changing the polarization direction of the emitted light that has passed through the second semi-transparent reflecting unit. (18) The eye information detection device according to any one of (1) to (17), further comprising a gaze detection unit that detects the line of sight of the eyeball based on the generated imaging data.(19) An eye information detection device according to any one of (1) to (18), further comprising an iris authentication unit that performs iris authentication of the eyeball based on the generated imaging data. (20) An eye information detection system comprising: an image display unit for displaying an image; a first semi-transparent reflecting unit that transmits at least a portion of incident light and reflects the other portion; a second semi-transparent reflecting unit that reflects one portion of linearly polarized incident light with polarization directions differing by approximately 90 degrees and transmits the other portion; a lens disposed between the first semi-transparent reflecting unit and the second semi-transparent reflecting unit; and a polarization state changing unit that mutually changes the polarization state of the incident light between linearly polarized and circularly polarized light, wherein the image light from the image display unit is incident on the side of the first semi-transparent reflecting unit and guides the image light to the user's eyeball; a light source unit that emits invisible light to the eyeball; an imaging unit that acquires reflected light from the invisible light emitted from the light source unit that is reflected by the eyeball and generates imaging data; and a polarization state adjustment unit that adjusts the polarization state of the light based on the emitted light.

[0112] 10 Eye Information Detection System 100 Eye Information Detection Device 110 Image Display Unit 120 Optical System 122 Polarizer 123, 127, 157, 167-169 Polarization State Changing Unit 125 First Semi-Transparent Reflector 128 Second Semi-Transparent Reflector 130 Light Source Unit 140 Imaging Unit 150 Polarization State Adjustment Unit 151, 152 Invisible Light Polarizer 153 Invisible Light Polarization Direction Changing Unit 154, 158 Invisible Light Polarization State Changing Unit 156 Diffractive Element 181 Control Unit 182 Gaze Detection Unit 183 Iris Recognition Unit

Claims

1. An eye information detection device comprising: a first semi-transparent reflecting section that transmits at least a portion of incident light and reflects the other portion; a second semi-transparent reflecting section that reflects one portion of linearly polarized incident light with polarization directions approximately 90 degrees different and transmits the other; a lens disposed between the first semi-transparent reflecting section and the second semi-transparent reflecting section; and a polarization state changing section that mutually changes the polarization state of the incident light between linearly polarized and circularly polarized light; an optical system into which image light from an image display section that displays an image is incident on the side of the first semi-transparent reflecting section and guides said image light to the user's eyeball; a light source section that emits invisible light to the eyeball; an imaging section that acquires reflected light from the invisible light emitted from the light source section that is reflected by the eyeball and generates imaging data; and a polarization state adjustment section that adjusts the polarization state of light based on the emitted light.

2. The eye information detection device according to claim 1, wherein the light source is arranged in a region other than between the optical system and the image display unit.

3. The eye information detection device according to claim 2, wherein the polarization state adjustment unit is composed of an invisible light polarizer that transmits invisible light in a predetermined polarization direction and is placed between the light source unit and the eyeball, and the invisible light polarizer adjusts the polarization state by transmitting the emitted light in a polarization direction that is reflected by the second semi-transparent reflecting unit of the emitted light.

4. The eye information detection device according to claim 2, wherein the polarization state adjustment unit comprises a polarizer that transmits the reflected light, which is light based on the emitted light, in a polarization direction that transmits through the second semi-transparent reflector, and an invisible light polarization direction changing unit that rotates the polarization direction of the reflected light, which is invisible light transmitted through the polarizer, by approximately 90 degrees, wherein the polarizer is disposed between the eyeball and the optical system, and the invisible light polarization direction changing unit is disposed between the polarizer and the optical system.

5. The eye information detection device according to claim 2, wherein the polarization state adjustment unit is composed of an invisible light polarization state changing unit that changes the polarization state of the invisible light and is located between the second semi-transparent reflecting unit and the first semi-transparent reflecting unit, and the polarization state is adjusted by converting the reflected light, which is light based on the emitted light, into circularly polarized light.

6. The eye information detection device according to claim 5, wherein the polarization state adjustment unit is composed of an invisible light polarizer that transmits invisible light in a predetermined polarization direction and an invisible light polarization state changing unit, which is arranged between the eyeball and the optical system, and transmits the emitted light in a polarization direction that is reflected by the second semi-transparent reflecting unit of the emitted light, and converts the reflected light based on said emitted light into circularly polarized light.

7. The eye information detection device according to claim 2, wherein the imaging unit is disposed between the optical system and the image display unit.

8. The eye information detection device according to claim 7, wherein the polarization state adjustment unit is composed of an invisible light polarization direction changing unit that rotates the polarization direction of the reflected light, which is invisible light, by approximately 90 degrees, and the polarization state is adjusted by changing the polarization direction of the reflected light, which is light based on the emitted light, that has passed through the second semi-transparent reflecting unit.

9. The eye information detection device according to claim 8, further comprising a diffracting element disposed between the optical system and the imaging unit, an invisible light polarization state changing unit that changes the polarization state of the invisible light, and an invisible light polarizer which is a polarizer that transmits the invisible light in a predetermined polarization direction, wherein the imaging unit acquires the reflected light that has been diffracted by the diffracting element and transmitted through the invisible light polarization state changing unit and generates imaging data.

10. The eye information detection device according to claim 7, wherein the polarization state changing unit changes the polarization state of visible light and invisible light, the polarization state adjustment unit is composed of the polarization state changing unit and an invisible light polarization state changing unit that changes the polarization state of invisible light, and the invisible light polarization state changing unit is arranged between the second semi-transparent reflecting unit and the polarization state changing unit.

11. The eye information detection device according to claim 10, further comprising a polarizer disposed between the eyeball and the optical system, which transmits the reflected light having a polarization direction that transmits through the second semi-transparent reflecting portion of the reflected light, which is light based on the emitted light.

12. The eye information detection device according to claim 11, further comprising a visible light / invisible light polarization state changing unit and a diffraction element disposed between the polarizer and the imaging unit, wherein the imaging unit acquires the reflected light transmitted through the visible light / invisible light polarization state changing unit and the diffraction element and generates imaging data.

13. The eye information detection device according to claim 1, wherein the light source unit irradiates the eyeball with emitted light through the optical system, the polarization state adjustment unit is composed of an invisible light polarization state changing unit that changes the polarization state of the invisible light, and the invisible light polarization state changing unit is positioned between the eyeball and the second semi-transparent reflecting unit, and adjusts the polarization state by converting the emitted light into circularly polarized light and converting the reflected light reflected by the eyeball from the converted emitted light into linearly polarized light in the polarization direction reflected by the second semi-transparent reflecting unit.

14. The eye information detection device according to claim 1, wherein the light source unit irradiates the eyeball with emitted light through the optical system, and the optical system further comprises a polarizer that transmits incident light in a predetermined polarization direction and a polarization state changing unit that changes the polarization state of the incident light, which are arranged between the first semi-transparent reflecting unit and the image display unit.

15. The eye information detection device according to claim 14, wherein the polarization state adjustment unit is composed of an invisible light polarization state changing unit that changes the polarization state of the invisible light, and the invisible light polarization state changing unit is positioned between the eyeball and the second semi-transparent reflecting unit, and adjusts the polarization state by converting the emitted light into circularly polarized light and converting the reflected light reflected by the eyeball from the converted emitted light into linearly polarized light in the polarization direction reflected by the second semi-transparent reflecting unit.

16. The eye information detection device according to claim 15, wherein the non-visible light polarization state changing unit has a mode for changing the polarization state of the non-visible light and a mode for not changing the polarization state of the invisible light.

17. The eye information detection device according to claim 1, wherein the light source is arranged between the second semi-transparent reflecting unit and the polarization state changing unit, and the polarization state adjustment unit is composed of an invisible light polarization direction changing unit that rotates the polarization direction of the emitted light, which is invisible light, by approximately 90 degrees, and adjusts the polarization state by changing the polarization direction of the emitted light that has passed through the second semi-transparent reflecting unit.

18. The eye information detection device according to claim 1, further comprising a gaze detection unit that detects the line of sight of the eyeball based on the generated imaging data.

19. The eye information detection device according to claim 1, further comprising an iris authentication unit that performs iris authentication of the eyeball based on the generated imaging data.

20. An eye information detection system comprising: an image display unit for displaying an image; a first semi-transparent reflecting unit that transmits at least a portion of incident light and reflects the other portion; a second semi-transparent reflecting unit that reflects one side of linearly polarized incident light with polarization directions differing by approximately 90 degrees and transmits the other; a lens disposed between the first semi-transparent reflecting unit and the second semi-transparent reflecting unit; and a polarization state changing unit that mutually changes the polarization state of the incident light between linearly polarized and circularly polarized light; an optical system to which image light from the image display unit is incident on the side of the first semi-transparent reflecting unit and guides said image light to the user's eyeball; a light source unit that emits invisible light to the eyeball; an imaging unit that acquires reflected light from the invisible light emitted from the light source unit reflected by the eyeball and generates imaging data; and a polarization state adjustment unit that adjusts the polarization state of light based on the emitted light.

Images