JP7424099B2 - Optical devices, retinal projection display devices, head-mounted display devices, and optometry devices - Google Patents

Description

The present invention relates to an optical device, a retinal projection display device, a head-mounted display device, and an optometry device.

The development of detection technology for pupil position (line of sight) is progressing, and it is now being used in a variety of applications such as interfaces for controlling electronic devices, image formation support for wearable display devices such as head-mounted displays, collection of gaze data from skilled engineers, and analysis of product attention. It is expected that it will be applied to various uses. Pupil position detection devices are required to have high detection responsiveness and to be compact and lightweight.

In response to these demands, a technology has been disclosed that detects the temporal change in the reflected light intensity of a laser beam scanned at high speed on the eyeball surface, and detects the pupil position at high speed using a non-imaging method that does not use an imaging system (for example, , see Patent Documents 1 and 2).

However, with the techniques of Patent Documents 1 and 2, the diameter of the laser beam expands on the light receiving surface of the photodetector due to reflection from the eyeball or cornea, which has a large curvature, and the pupil position may not be detected properly. .

The disclosed technology aims to appropriately detect the pupil position.

An optical device according to one aspect of the disclosed technology includes a light source unit that emits light, a focusing and reflecting unit that focuses light from the light source unit and reflects it toward an eyeball , and detects the position of the reflected light from the eyeball . and a position detection means , and the focusing reflection means has a curvature determined so as to offset the divergence of the reflected light from the eyeball .

According to the disclosed technology, the pupil position can be appropriately detected.

FIG. 1 is a diagram illustrating an example of the configuration of a pupil position detection device according to a first embodiment. FIG. 4 is a diagram illustrating the relationship between rotation of the eyeball and the incident position of the laser beam on the PSD, in which (a) is a diagram illustrating a state in which the eyeball is not rotated, and (b) is a diagram illustrating a state in which the eyeball is rotated. FIG. FIG. 3 is a diagram illustrating conditions that an off-axis optical system should satisfy, in which (a) is a diagram illustrating distances between elements, and (b) is a diagram illustrating geometric distance relationships expressed in a coaxial optical system. FIG. 3 is a diagram showing an example of the relationship between the effective area diameter of a concave mirror and the beam radius of a laser beam on a PSD light receiving surface. FIG. 2 is a block diagram illustrating an example of the hardware configuration of a processing unit according to the first embodiment. FIG. 2 is a block diagram illustrating an example of the functional configuration of a processing section according to the first embodiment. 7 is a flowchart illustrating an example of processing by the pupil position detection device according to the first embodiment. FIG. 3 is a diagram (part 1) illustrating an example of the configuration of the main parts of the pupil position detection device according to the first modification, in which (a) is an arrangement where the optical path from the VCSEL to the concave mirror and the optical path from the eyeball to the PSD intersect; (b) is a diagram showing an arrangement in which the optical path from the VCSEL to the concave mirror and the optical path from the eyeball to the PSD do not intersect. FIG. 7 is a diagram (part 2) illustrating an example of the configuration of the main parts of the pupil position detection device according to the second modification. FIG. 7 is a diagram (part 3) illustrating an example of the configuration of a main part of a pupil position detection device according to a third modification. FIG. 4A is a diagram (part 4A) illustrating an example of the configuration of a main part of a pupil position detection device according to a modification 4A, in which (a) is a view of the main part seen from above, and (b) is a part of (a). It is a figure which looked at B from the eyeball side. FIG. 4B is a diagram (part 4B) illustrating an example of the configuration of the main part of the pupil position detection device according to the 4B modification, in which (a) is a view of the main part seen from above, and (b) is the part in (a). Part B is seen from the eyeball side, and (c) is a diagram of part B in (a) seen from the side opposite to the eyeball. FIG. 12 is a diagram (part 5) illustrating an example of the configuration of a main part of a pupil position detection device according to a fifth modification. FIG. 6 is a diagram (part 6) illustrating an example of the configuration of a main part of a pupil position detection device according to a sixth modification, in which (a) is a diagram of a concave mirror viewed from the direction facing the concave surface, and (b) is It is a figure which shows the AA' cross section of a). FIG. 7 is a diagram (part 7) illustrating an example of the configuration of the main part of the pupil position detection device according to the seventh modification, in which (a) is a view of the main part seen from above, and (b) is the part in (a). It is a figure which looked at C from the eyeball side. FIG. 3 is a diagram illustrating an example of the configuration of a non-coaxial concave mirror. It is a figure explaining an example of a undiffracted beam. 2A and 2B are diagrams illustrating an example of the configuration of an off-axis optical system using an HOE, in which (a) is a diagram illustrating a case in which the HOE generates one focused laser beam, and (b) is a diagram illustrating a case in which the HOE generates a plurality of focused laser beams. FIG. FIG. 3 is a diagram illustrating a focusing reflection means including a liquid crystal reflective light focusing structure. FIG. 2 is a diagram illustrating the alignment state of liquid crystal molecules within a liquid crystal reflective light condensing structure. FIG. 3 is a diagram illustrating the polarization states of incident and outgoing light rays by a liquid crystal reflective light condensing structure. FIG. 3 is a diagram illustrating a light guiding means coupling optical system using a liquid crystal reflection type condensing structure. FIG. 7 is a diagram illustrating an example of the configuration of a retinal projection display device according to a second embodiment. 1 is a diagram showing the configuration of an eye tracking device described in Patent Document 1. FIG.

Hereinafter, embodiments for carrying out the invention will be described with reference to the drawings. In each drawing, the same components are designated by the same reference numerals, and redundant explanations may be omitted.

As an example of an optical device, a pupil position detecting device of an eyeball will be described in the embodiment, and a case where the pupil position detecting device is mounted on a glasses-type support will be described as an example.

In each embodiment, the right eyeball of a "person" will be described as an example, but the same applies to the left eyeball. It is also possible to provide two optical devices or two retinal projection display devices and apply them to the eyeballs of both eyes.

[First embodiment]
<Configuration of pupil position detection device according to first embodiment>
FIG. 1 is a diagram illustrating an example of the configuration of a pupil position detection device according to this embodiment.

As shown in FIG. 1, the pupil position detection device 10 includes a VCSEL (Vertical Cavity Surface Emitting Laser) 1, a concave mirror 2, a PSD (Position Sensitive Detector) 3, and a processing unit 100. has.

The VCSEL 1, concave mirror 2, and PSD 3 are arranged on an optical system support 4. The optical system support 4 is tiltably fixed to a spectacle frame 22 of a spectacle-type support 20 including a spectacle lens 21 and a spectacle frame 22 via a ball joint 4a. The inclination of the optical system support 4 can be adjusted via the ball joint 4a. The ball joint 4a constituting the installation fine adjustment mechanism can be fixed by using mechanical pressure between the spherical structure and its outer shell structure, or by fixing the ball joint 4a between the magnetized spherical structure and the metal opening structure. A fixing method using magnetic force can be used.

The glasses-type support 20 can be worn on a person's head. When the glasses-type support 20 is attached, the optical system including the VCSEL 1, the concave mirror 2, and the PSD 3 is placed close to the eyeball 30 (in front of the eye).

The VCSEL 1 as an example of "light source means" has a plurality of light emitting parts arranged two-dimensionally within a plane. Each light emitting section emits laser light having directivity and a finite spread angle. Here, the emitted laser light is an example of "light". Moreover, "a plurality of light emitting parts" is synonymous with "a plurality of light emitting points" or "a plurality of light emitting elements".

However, the light source means is not limited to a VCSEL as long as it can emit light. The light source means may be configured by two-dimensionally arranging a plurality of LDs (laser diodes) or LEDs (light emitting diodes) in a plane that emit laser light. Alternatively, a pulsed laser that emits pulsed laser light may be used. Furthermore, the light source means may be configured by combining a plurality of types of light sources.

Further, the wavelength of the laser light emitted from the VCSEL 1 is preferably the wavelength of near-infrared light, which is invisible light, so as not to obstruct the visibility of the "person" whose pupil position is being detected. However, the light is not limited to this, and visible light may be used.

The laser beam L0 emitted from the VCSEL 1 directs the space in front of the eyes toward the concave mirror 2 in a direction substantially parallel to the face of the person wearing the spectacle-type support 20 or the lens surface of the spectacle lens 21 worn. propagate. Further, the laser beam L0 is a diverging beam that propagates while expanding the beam diameter due to diffraction at the exit opening of the VCSEL 1. The divergence angle of the diverging light can be controlled by the shape of the aperture of the exit section. The laser beam L0 propagates while diverging and enters the concave mirror 2.

The concave mirror 2, which is an example of a focusing and reflecting means, has a reflecting surface with curvature, reflects the incident laser beam L0, and irradiates the eyeball 30 with a focused laser beam (also expressed as focused light) L1. The focused laser beam L1 enters the vicinity of the pupil 31 of the eyeball 30. The center of curvature of the concave surface of the concave mirror 2 is located off the optical axis of the optical path from the VCSEL 1 to the concave mirror 2, and the optical system including the VCSEL 1, the concave mirror 2, and the PSD 3 constitutes a so-called off-axis optical system. ing.

In the off-axis optical system according to the present embodiment, the light before reaching the eyeball 30 propagates through the space in front of the eye adjacent to the eyeball 30 by turning around at least once or more without being reflected or scattered by the eyeball 30. After that, the eyeball 30 is reached.

The angle of incidence of the focused laser beam L1 on the eyeball 30 is adjusted so that it enters the center of the pupil 31 of the eyeball 30 at a predetermined angle during normal vision. Further, the VCSEL 1 can emit laser light from a plurality of light emitting parts, and the laser light emitted from the plurality of light emitting parts is irradiated to a plurality of places on the eyeball 30 or irradiated to the eyeball 30 at a plurality of angles. Ru.

In addition to having a plurality of light emitting sections as described above, the VCSEL 1 is capable of high-speed modulation. By time-modulating the laser light irradiated to the eyeball 30 and extracting a component with a modulation frequency that matches the incident laser light from the output signal obtained by the PSD 3, the influence of light from the external environment (without modulation) can be eliminated. can be removed. As a result, the SN ratio can be improved, which is advantageous in detecting the pupil position in a bright environment. Furthermore, the amount of laser light irradiated onto the eyeball can also be reduced.

The pupil surface (corneal surface) of the eyeball 30, which is an example of the irradiated surface, is a transparent body containing water and generally has a reflectance of about 2 to 4%. The focused laser beam L1 that has entered the vicinity of the pupil 31 of the eyeball 30 is reflected (also expressed as reflected light) on the surface of the pupil 31 of the eyeball 30, and the reflected light propagates toward the PSD 3. In addition, below, in order to simplify description, the surface of the eyeball 30 may be called the eyeball 30, the surface of the pupil 31 may be called the pupil 31, and the surface of the cornea 32 may be called the cornea 32.

Here, the curvature of the reflective surface of the concave mirror 2 is determined so as to offset the divergence of the reflected laser light due to the curvature of the eyeball 30 or the cornea 32. By doing so, it is possible to prevent the beam diameter of the laser light L2 propagating toward the PSD 3 from expanding on the light receiving surface of the PSD element.

Although a concave mirror is shown as an example of a focusing/reflecting means, it is not limited to this as long as it can focus (converge) light; A wavefront control element using a diffractive optical element, a diffractive optical element, etc. may also be used.

Furthermore, if an anamorphic aspheric surface with different curvatures in two orthogonal directions within a plane intersecting the optical axis of the focused laser beam L1 is used as the concave surface of the concave mirror, the beam diameter of the laser beam L2 can be further miniaturized. The beam can be shaped into an isotropic state.

Furthermore, the irradiated surface is not limited to the eyeball 30, and the present embodiment can be applied to any three-dimensional object having a curvature.

The PSD 3, which is an example of a "position detection means", detects the current value according to the distance of the incident light to the electrode in two orthogonal directions within the light receiving surface, and calculates the current value of the incident light from the ratio of the current values in the two orthogonal directions. This is a two-dimensional optical position detecting element that calculates and outputs a detection signal indicating the position of the object. The PSD 3 can output a detection signal indicating the position of a beam spot formed on the light receiving surface of the PSD 3.

More specifically, the PSD 3 includes four output terminals, a resistive film is disposed on a continuous light receiving surface (a light receiving surface not divided into pixels), and electrode pairs are provided in two orthogonal directions. The photocurrent generated at the beam spot position is divided into four parts depending on the distance from each output terminal. At this time, the electrical resistance caused by the resistive film acts so that the longer the distance between the beam spot position and the output terminal, the smaller the current. The PSD 3 can detect the electrical signal that has passed through the resistive film through four terminals, and can output a detection signal indicating the position within the light receiving surface obtained by electrical post-processing.

Further, the PSD 3 can convert the current generated by photoelectric conversion into an analog voltage signal and output it as a detection signal from four terminals. In other words, the PSD 3 can detect the position of incidence by determining the distance to each terminal using surface resistance.

By the way, when an image sensor (imaging device) is used as a position detection means instead of the PSD 3, the output result of the image sensor changes depending on the intensity of light incident on each pixel, and when the intensity is low, the output current decreases. In order to reduce the influence of noise light such as sunlight, it is necessary to increase the output of the light source to increase the intensity of the light incident on the image sensor. In this case, increasing the intensity of the incident light is not preferable from the viewpoint of safety for the eyes.

Furthermore, in the case of an image sensor, image processing is required to detect the position, but a positional accuracy error may occur during the processing, and the processing load also increases.

By using PSD3 as a position detection means, the position is detected using the current division ratio (ratio) divided between the output terminals, so the position of the incident light can be detected without depending on the intensity of the incident light. This method is suitable because it does not require image processing.

However, the configuration of the PSD 3 described above is just an example, and other configurations may be used. Although an example of a two-dimensional PSD that detects a two-dimensional position within the light-receiving surface is shown as the PSD 3, a one-dimensional PSD that detects a one-dimensional position within the light-receiving surface may also be used.

The processing unit 100 outputs a control signal to drive the VCSEL 1 to emit light. Furthermore, the processing unit 100 receives a detection signal from the PSD 3 and executes a process of detecting the position of the pupil 31 of the eyeball 30, as described later. For example, the processing unit 100 can be placed in the eyeglass frame 22 or the like.

Since the position of the beam spot formed by the laser beam L2 on the light receiving surface of the PSD 3 changes depending on the inclination of the eyeball 30, the processing unit 100 detects the pupil position of the eyeball 30 by converting the detection signal of the PSD 3 into coordinate information. can do.

The PSD 3 can detect the position of the reflection point and the direction of the normal vector on the eyeball 30, and the pupil position detection device 10 can detect the position and normal vector of the detected reflection point and the surface shape model of the eyeball. Based on the correspondence, the pupil position can be "estimated".

Although FIG. 1 shows an example in which the optical system and the processing unit are arranged in the eyeglass frame 22, the present invention is not limited to this, and a head-mounted display, a headgear-type holding structure, or the like may be used.

<Following operation of the pupil position detection device according to the first embodiment to eye movement>
Next, the operation of the pupil position detection device 10 to follow eyeball movements will be described.

Since the eyeball 30 makes eyeball movements such as rotation, the direction of the laser light L2 changes due to the rotation, which may cause the laser light L2 to deviate from the light receiving surface of the PSD 3. In contrast, the pupil position detection device 10 can prevent the laser beam L2 from deviating from the light receiving surface of the PSD 3 by performing control to sequentially or selectively change the light emitting portion that causes the VCSEL 1 to emit light.

FIG. 2 is a diagram illustrating the relationship between the rotation of the eyeball 30 and the incident position of the laser beam L2 on the PSD 3, in which (a) is a diagram illustrating a state where the eyeball is not rotated (during normal vision), and (b) ) is a diagram illustrating a state in which the eyeball is rotating.

FIG. 2 shows the propagation of laser light emitted from the two light emitting parts of the VCSEL 1. Laser light 11 emitted from one light emitting part is shown by a solid line, and laser light 12 emitted from the other light emitting part is shown by a broken line.

In FIG. 2A, the laser beam 11 reflected by the eyeball 30 is incident near the center of the light receiving surface of the PSD 3. In FIG. Therefore, the PSD 3 can detect the position of the laser beam 11 on the light receiving surface, and the pupil position detection device 10 can detect the position of the pupil 31 based on the detection signal of the PSD 3.

On the other hand, since the laser beam 12 reflected by the eyeball 30 is not incident on the light receiving surface of the PSD 3, the PSD 3 cannot detect the position of the laser beam 12 on the light receiving surface, and the pupil position detection device 10 detects the position of the pupil 31. Unable to detect location.

Moreover, when the eyeball 30 rotates significantly, the laser beam 11 reflected by the eyeball 30 does not enter the light receiving surface of the PSD 3, as shown in FIG. 2(b). Therefore, the PSD 3 cannot detect the position of the laser beam 11 on the light receiving surface, and the pupil position detection device 10 cannot detect the position of the pupil 31.

On the other hand, since the laser beam 12 reflected by the eyeball 30 is incident near the center of the light receiving surface of the PSD 3, the PSD 3 can detect the position of the laser beam 12 on the light receiving surface, and the pupil position detection device 10 can detect the position of the pupil 31 based on the detection signal of the PSD 3.

In this way, the pupil position of the eyeball 30 can only be detected in a limited angular range with light from only one light emitting section, but by changing the light emitting section of the VCSEL 1, it is possible to detect the position of the pupil of the eyeball 30 using light emitted from any one of the light emitting sections. Laser light can be made incident on the light receiving surface of the PSD 3. Thereby, even if the eyeball 30 rotates, it is possible to reduce the situation in which the laser light reflected by the eyeball 30 does not enter the light receiving surface of the PSD 3, and to expand the range in which the pupil position can be detected.

In other words, the PSD 3 detects the slight movement of the laser beam 12 based on the rotational movement of the eyeball 30, and the array of the plurality of light emitting parts of the VCSEL 1 detects the coarse movement of the laser beam 12 based on the rotational movement of the eyeball 30. In detecting the rotational angle of the rotational movement of 30, it is possible to achieve both high detection resolution and a wide detection range.

The light emitting section of the VCSEL 1 can be changed in time series according to (following) the eye movement of the eyeball 30 using a drive signal from the processing section 100. Furthermore, by controlling the light emitting section according to the rotational movement of the eyeball 30, it is possible to improve the efficiency of light use and shorten the estimation time.

However, it is not necessarily necessary to change the light emitting part of the VCSEL 1 according to the rotational movement of the eyeball. For example, the pupil position detection device 10 causes the light emitting part of the VCSEL 1 to raster scan (sequentially emit light) at predetermined time intervals independently of eye movement, and determines the coarse movement position of the eyeball 30 based on the detection signal of the PSD 3 in that case. It may also be possible to detect.

In addition, in FIG. 2, in order to simplify the explanation, only the laser light emitted from two light emitting parts is illustrated, but more light emitting parts of the VCSEL 1 can be used according to the rotation of the eyeball 30. In this case, it is preferable to optimize the number and position of the light emitting parts of the VCSEL 1 according to the size of the light receiving surface of the PSD 3 and the size of the eyeball 30 so that the position of the pupil 31 can be detected appropriately.

<Conditions for off-axis optical system>
Next, conditions to be satisfied by the off-axis optical system including the VCSEL 1, concave mirror 2, and PSD 3 will be described.

In this embodiment, a concave mirror is used as a condition for the laser beam emitted from the VCSEL 1 to enter the light receiving surface of the PSD 3, and as a condition for the focused laser beam L1 to be converted into parallel light after being reflected by the cornea 32. The diameter of the effective area (area that can reflect laser light; effective diameter) of No. 2 is determined.

FIG. 3 is a diagram explaining the conditions that an off-axis optical system should satisfy, where (a) is a diagram explaining the distance between elements, and (b) is a diagram explaining the geometric distance relationship expressed in a coaxial optical system. It is a diagram.

As shown in FIG. 3A, the distance from the VCSEL 1 to the concave mirror 2 is d0, the distance from the concave mirror 2 to the cornea 32 is d1, and the distance from the cornea 32 to the PSD 3 is d2. Further, focusing on the curvature and effective area of the concave mirror 2, for simplicity, a coaxial optical system in which the VCSEL 1, the concave mirror 2, and the PSD 3 are coaxially arranged is assumed.

FIG. 3(b) shows that the diverging laser beam from the VCSEL 1 enters the concave mirror 2, the laser beam reflected by the concave mirror 2 enters the cornea 32 while converging, and then the laser beam reflected by the cornea 32 The figure shows how the light enters the PSD3. A position 41 indicates the position of the light emitting part of the VCSEL 1, a position 42 indicates the position of the surface of the cornea 32, and a position 43 indicates the position of the surface of the concave mirror 2.

The beam radius hPSD can be calculated using the following equation (1) derived by ray tracing using the ABCD matrix.

・・・（１）
（１）式において、ｒｃは角膜３２の曲率半径、ｈＰＳＤはＰＳＤ３の受光面でのレーザ光のビームの半径、Ｄｍは凹面ミラー２の有効領域の直径、λはＶＣＳＥＬ１の波長、ｈＵＬはＰＳＤ３の受光面でのレーザ光の、設計者が決定するビームの半径の上限値である。また、中央の式の第２項で、凹面ミラー２で反射後のレーザ光の回折によるレーザ光の広がりの効果が重畳されている。

...(1)
In equation (1), rc is the radius of curvature of the cornea 32, hPSD is the radius of the laser beam on the light receiving surface of the PSD 3, Dm is the diameter of the effective area of the concave mirror 2, λ is the wavelength of the VCSEL 1, and hUL is the radius of the PSD 3. This is the upper limit value of the radius of the laser beam on the light receiving surface, determined by the designer. Furthermore, in the second term of the central equation, the effect of the spread of the laser beam due to the diffraction of the laser beam after being reflected by the concave mirror 2 is superimposed.

Based on equation (1), the diameter Dm of the effective area of the concave mirror 2 can be determined from equation (2).

・・・（２）
ここで、図４は、（２）式に基づき取得された、凹面ミラー２の有効領域の直径Ｄｍと、ＰＳＤ３の受光面でのレーザ光のビームの半径ｈＰＳＤとの関係の一例を示す図である。

...(2)
Here, FIG. 4 is a diagram showing an example of the relationship between the diameter Dm of the effective area of the concave mirror 2 and the radius hPSD of the laser beam on the light receiving surface of the PSD 3, obtained based on equation (2). be.

In the relationships shown in FIG. 4, the upper limit of the radius hPSD of the laser beam on the light receiving surface of the PSD 3 is hUL = 200 um, the distance d1 from the concave mirror 2 to the cornea 32 is 24 mm, the radius of curvature rc of the cornea 32 is 8 mm, The wavelength λ of the laser light is 940 nm. Although these values are values assuming the glasses-type support body 20, arbitrary values may be set depending on the purpose and environment of use.

In FIG. 4, as the diameter Dm of the effective area of the concave mirror 2 becomes smaller, the radius hPSD of the beam on the light receiving surface of the PSD 3 rapidly expands due to diffraction. Furthermore, as the diameter Dm of the effective area of the concave mirror 2 increases, the radius hPSD of the beam on the light receiving surface of the PSD 3 gradually increases. As the beam radius hPSD increases, the position detection resolution of the laser beam by the PSD 3 decreases.

As shown in FIG. 4, the diameter Dm of the effective area of the concave mirror 2 has an appropriate range in order to minimize the radius hPSD of the beam on the light receiving surface of the PSD 3. The gray hatched area is an appropriate range, which is the range of the diameter Dm of the effective area of the concave mirror 2 that satisfies equation (2). Applying equation (2), the diameter Dm of the effective area of the concave mirror 2 is determined by 0.225 mm≦Dm≦2.574 mm. By satisfying this condition, the radius hPSD of the beam on the light receiving surface of the PSD 3 can be set to 200 μm or less, and the position detection resolution of the laser beam by the PSD 3 can be made appropriate.

If d0 = 24√3 (mm) as a condition for the laser beam to enter the eyeball 30 at an incident angle of 60°, then the laser beam emitted from the VCSEL 1 has a divergence angle of approximately 7.1° or less in full width. Although necessary, this divergence angle can be realized by controlling the aperture of the VCSEL 1.

<Configuration of processing section of pupil position detection device according to first embodiment>
Next, the hardware configuration of the processing unit 100 according to this embodiment will be explained. FIG. 5 is a block diagram illustrating an example of the hardware configuration of the processing unit 100.

The processing unit 100 includes a CPU (Central Processing Unit) 101, a ROM (Read Only Memory) 102, a RAM (Random Access Memory) 103, an SSD (Solid State Drive) 104, a light source drive circuit 105, and an A/D. It has an (Analog/Digital) conversion circuit 106 and an input/output I/F (Interface) 107. Each of them is interconnected by a system bus 108.

The CPU 101 reads programs and data from a storage device such as the ROM 102 and the SSD 104 onto the RAM 103 and executes processing, thereby controlling the entire processing unit 100 and realizing functions described below. Note that some or all of the functions of the CPU 101 may be realized by hardware such as an ASIC (application specific integrated circuit) or an FPGA (field-programmable gate array).

The ROM 102 is a nonvolatile semiconductor memory (storage device) that can retain programs and data even when the power is turned off. The ROM 102 stores programs and data such as a BIOS (Basic Input/Output System) and OS settings that are executed when the processing unit 100 is started. The RAM 103 is a volatile semiconductor memory (storage device) that temporarily holds programs and data.

The SSD 104 is a nonvolatile memory that stores programs for executing processing by the processing unit 100 and various data. Note that the SSD may be an HDD (Hard Disk Drive).

The light source drive circuit 105 is an electric circuit that is electrically connected to the VCSEL 1 and outputs a drive signal such as a drive voltage to the VCSEL 1 according to an input control signal. The light source drive circuit 105 can drive a plurality of light emitting parts included in the VCSEL 1 to emit light simultaneously or sequentially. Furthermore, by modulating the cycle of the drive voltage, it is possible to drive the light emission with different light emission cycles.

As the drive voltage, a voltage waveform of a rectangular wave, a sine wave, or a predetermined waveform can be used. The light source drive circuit 105 can modulate the cycle of the drive voltage signal by changing the cycle (frequency) of the voltage waveform.

The A/D conversion circuit 106 is an electric circuit that is electrically connected to the PSD 3 and outputs a digital voltage signal obtained by A/D converting the analog voltage signal output from the PSD 3.

The input/output I/F 107 is an interface for connecting to external devices such as a PC (Personal Computer) and video equipment.

Next, the functional configuration of the processing unit 100 according to this embodiment will be explained. FIG. 6 is a block diagram illustrating an example of the functional configuration of the processing unit 100. As shown in FIG. 6, the processing section 100 includes a light emission driving section 110, a detection signal input section 111, a calculation section 120 as an example of calculation means, and a pupil position output section 130.

The light emitting drive unit 110 outputs a drive signal with a cycle T1 to the VCSEL1, and drives the light emitting unit included in the VCSEL1 to emit light with a cycle T1. The light emission driving section 110 can be realized by the light source driving circuit 105 or the like.

The detection signal input unit 111 is realized by the A/D conversion circuit 106 and the like, and outputs a digital voltage signal obtained by A/D converting the analog voltage signal input from the PSD 3 to the eyeball rotation angle estimation unit 121 included in the calculation unit 120. .

The calculation unit 120 includes an eye rotation angle estimation unit 121 and a pupil position acquisition unit 122, and executes calculation processing to acquire the pupil position of the eyeball 30 based on the input signal from the detection signal input unit 111.

The eyeball rotation angle estimation section 121 estimates the rotation angle of the eyeball 30 based on the input signal from the detection signal input section 111 and outputs the estimated rotation angle data to the pupil position acquisition section 122. The pupil position acquisition unit 122 executes a process of acquiring the position of the pupil 31 based on the estimated rotation angle of the eyeball 30. The acquired position data of the pupil 31 is output to an external device or the like via the pupil position output unit 130 realized by the input/output I/F 107 or the like.

<Processing by the pupil position detection device according to the first embodiment>
Next, processing by the pupil position detection device according to this embodiment will be explained.

Here, in the pupil position detection device 10, as a preliminary preparation for pupil position detection, calculation formulas for the incident angle at which the laser beam irradiated onto the eyeball 30 by the VCSEL 1 enters the eyeball 30 and the rotation angle of the eyeball 30 are determined in advance. Therefore, these will be explained first.

The formula for calculating the rotation angle of the eyeball 30 is a linear function or a quadratic function. However, the formula is not limited to this, and the format of the formula is not limited as long as it can determine the rotation angle from the incident angle of the laser beam and the position on the light receiving surface of the PSD 3. As a simple approximation formula, this embodiment employs a calculation formula using a quadratic function.

A surface shape model of the eyeball 30 can be used to determine the angle at which the laser beam enters the eyeball 30. For example, a schematic model of the eye that has been known for a long time as a general eyeball surface shape model (see, for example, "Optical Mechanism of the Eye", Precision Instruments 27-11, 1961), etc. can be used.

On the other hand, the angle of incidence of the laser light on the eyeball 30 is determined in advance by ray tracing calculation or the like so that the position of incidence of the laser light on the PSD 3 is at the center of the light receiving surface.

In addition, the incident position of the laser beam on the light receiving surface of the PSD 3 should be theoretically analyzed based on the incident angle of the laser beam on the eyeball 30, the reflection position of the laser beam on the eyeball 30, and the inclination of the contact surface of the eyeball 30. Can be done. Then, from the solution of the theoretical analysis, it is possible to determine an inverse calculation formula (approximate formula) for estimating the rotation angle of the eyeball 30 by polynomial approximation.

The inverse calculation formula for estimating the incident angle of the laser beam on the eyeball 30 and the rotation angle of the eyeball 30 is stored in a memory such as the ROM 102 or the SSD 104 of the processing unit 100, and is used to change the light emitting unit by the light emission driving unit 110 or perform calculations. It is referred to in the pupil position acquisition processing performed by the unit 120.

Next, FIG. 7 is a flowchart showing an example of processing by the pupil position detection device according to this embodiment.

First, in step S71, the light emission driving section 110 drives the VCSEL 1 to emit light at the light emission period T1.

Subsequently, in step S72, the detection signal input unit 111 inputs the detection signal of the PSD 3 and outputs it to the eyeball rotation angle estimation unit 121 included in the calculation unit 120.

Subsequently, in step S73, the eyeball rotation angle estimation unit 121 calculates the eyeball rotation angle by substituting the input signal from the detection signal input unit 111 into an inverse calculation formula for estimating the rotation angle. Then, the calculated eyeball rotation angle data is output to the pupil position acquisition unit 122.

Subsequently, in step S74, the pupil position acquisition unit 122 acquires the pupil position using the eyeball surface shape model based on the input eyeball rotation angle data. The acquired pupil position data is output to an external device via the pupil position output unit 130.

In this way, the processing unit 100 can acquire the position of the pupil 31 of the eyeball 30 based on the detection signal output by the PSD 3, and can output the acquired position data to an external device.

<Effects, etc.>
The development of technology to detect pupil position (line of sight) has progressed, and it has become useful as an interface for controlling electronic devices using line of sight, image formation support in wearable video display devices such as head-mounted displays or near-eye displays, and line of sight for skilled engineers in factories, etc. It is expected to be applied to a variety of applications, including data collection and product attention analysis (logging). In particular, pupil position detection devices that function as an interface between electronic devices and people require real-time performance and a reduction in size and weight.

With conventional technology, the reflected image of the eyeball is acquired under a lighting environment, and the pupil position is detected by an image processing unit based on pattern matching, which requires a large image processing load.Also, real-time performance and detection resolution of the pupil position are insufficient. There was a trade-off relationship between the two. Furthermore, it was necessary to install an imaging device, a processor, a driving power source, etc., making it difficult to make the device smaller and lighter.

Further, as a conventional technique, a technique has been disclosed in which the pupil position is detected at high speed by a non-imaging method that does not use an imaging system by detecting the temporal change in the reflected light intensity of a laser beam scanned at high speed on the eyeball surface. However, with this technique, the diameter of the laser beam expands on the light receiving surface of the photodetector due to reflection from the eyeball or cornea, which has a large curvature, and the pupil position may not be detected properly.

In this embodiment, a VCSEL 1 that emits light, a concave mirror 2 that converts the light into focused light and returns the focused light toward an irradiated surface having a curvature, and a concave mirror 2 that converts the reflected light of the focused light from the irradiated surface. An off-axis optical system including a PSD 3 that receives light and detects the position of the reflected light is placed in front of the eye.

More specifically, before reaching the eyeball 30, the light propagates through the space in front of the eye adjacent to the eyeball 30, turning around at least once or more without being reflected or scattered by the eyeball 30, and then reaches the eyeball 30. . Further, the concave mirror 2 emits focused laser light toward the eyeball 30.

Thereby, the curvature of the eyeball 30 or the cornea 32 can be offset by the curvature of the focused laser beam, so that the laser light reflected by the eyeball 30 or the cornea 32 can be prevented from spreading.

Furthermore, by determining the diameter (aperture) Dm of the effective area of the concave mirror 2 so as to satisfy the condition of equation (2), the diameter Dm of the effective area of the concave mirror 2 can be increased, and the large aperture allows the laser beam to be emitted. Since the beam can be focused, the diameter of the beam at the light receiving surface of the PSD 3 can be reduced.

In this way, by miniaturizing the diameter of the laser beam on the light receiving surface of the PSD 3, the position detection resolution of the PSD 3 and the detection accuracy of the pupil position can be ensured, and the pupil position can be detected appropriately. .

Here, since the pupil position detection device according to the present embodiment can be modified in various ways, these modifications will be described below.

(First modification)
FIG. 8 is a diagram (part 1) illustrating an example of the configuration of a main part of the pupil position detection device according to the first modification. (a) is a diagram showing the arrangement where the optical path of the laser beam from the VCSEL 1 to the concave mirror 2 and the optical path from the eyeball 30 to the PSD 3 intersect, and (b) is the optical path of the laser beam from the VCSEL 1 to the concave mirror 2 and the eyeball. 30 is a diagram showing an arrangement in which optical paths from PSD 30 to PSD 3 do not intersect. FIG.

The off-axis optical system in FIG. 8(a) has an optical path 81 (indicated by a broken line) of the laser beam from the VCSEL 1 to the concave mirror 2, and an optical path 82 (indicated by a dashed line) from the concave mirror 2 to the eyeball 30 or cornea 32. and an optical path 83 from the cornea 32 to the PSD 3 (the optical path shown by a two-dot chain line).

When the eyeball 30 is in a normal vision state, the optical path 81, the optical path 82, and the optical path 83 are in the same plane, and the optical path 81 and the optical path 83 intersect. Note that although there are cases where the light emitting portion of the VCSEL 1 deviates from the same plane depending on the position, such a case is also included in "within the same plane."

In FIG. 8A, the VCSEL 1 is arranged perpendicularly to the optical path 81, and the PSD 3 is arranged perpendicularly to the optical path 83. By doing so, the length of each optical path can be increased, and the beam spot of the laser beam on the light receiving surface of the PSD 3 can be prevented from becoming oval. Thereby, the diameter of the beam can be miniaturized and the position detection resolution by the PSD 3 can be improved.

On the other hand, the off-axis optical system in FIG. 8(b) has an optical path 84 (the optical path indicated by a broken line) of the laser beam from the VCSEL 1 to the concave mirror 2, and an optical path 85 (one point) from the concave mirror 2 to the eyeball 30 or cornea 32. and an optical path 86 from the cornea 32 to the PSD 3 (an optical path indicated by a two-dot chain line). The point that optical paths 84, 85, and 86 are in the same plane is the same as in FIG. 8(a).

The optical path 84 is arranged parallel to the reference illuminated surface 90, which is a tangential plane on which the inclination of the eyeball 30 in the emmetropic state is zero. Here, the reference irradiated surface 90 is an example of a "reference plane." By doing so, the exit surface of the VCSEL 1 can be made perpendicular to the reference irradiated surface 90, and the light receiving surface of the PSD 3 and the exit surface of the VCSEL 1 can be arranged in the same plane. This makes it possible to arrange the VCSEL 1 and PSD 3 on the same substrate, making it easy to mount both.

(Second modification)
FIG. 9 is a diagram (part 2) illustrating an example of the configuration of main parts of the pupil position detection device according to the second modification.

In FIG. 9, the off-axis optical system includes an optical path 91 of the laser beam from the VCSEL 1 to the concave mirror 2 (the optical path indicated by a broken line), and an optical path 92 from the concave mirror 2 to the eyeball 30 or the cornea 32 (the optical path indicated by the dashed line). ), and an optical path 93 from the cornea 32 to the PSD 3 (the optical path indicated by a two-dot chain line). By intersecting the optical path 91 and the optical path 93, the optical path length can be increased.

The VCSEL 1 is arranged at an angle with respect to the normal viewing direction of the eyeball 30 indicated by the white arrow 80 so that the laser light emitted perpendicularly to the exit surface is incident near the center of the concave mirror 2.

Further, the VCSEL 1 and the PSD 3 are mounted on an FFC (flexible flat cable) 52 fixed to the element support 50. By mounting the VCSEL 1 and PSD 3 on the same FFC 52, power supply lines and signal lines can be efficiently arranged. Here, the FFC 52 is an example of an "electronic board."

Further, a battery 53 for driving the VCSEL 1 and the PSD 3, a circuit group 55, and other driving units are fixed on an FPC (flexible substrate) 51. The FPC 51 is fixed to the surface of the element support 50 opposite to the mounting surface of the VCSEL 1 and PSD 3. By wiring the FFC 51 to the FPC 51 via the connector 54, the drive section can save space.

Here, the circuit group includes an IV conversion circuit using a transimpedance amplifier (TIA) or the like, an AD conversion circuit, a pupil position estimation circuit, an arithmetic operation circuit, an FPGA circuit, a wireless transmission circuit, and the like.

Further, the PSD 3 can be easily mounted by being arranged in a direction parallel to the normal viewing direction of the eyeball 30. However, the PSD 3 may be arranged so that the light receiving surface is perpendicular to the optical path 93. This prevents the beam spot of the laser beam on the light receiving surface of the PSD 3 from becoming elliptical, reduces the beam diameter, and improves the position detection resolution of the PSD 3.

(Third modification)
FIG. 10 is a diagram (Part 3) illustrating an example of the configuration of the main parts of the pupil position detection device according to the third modification.

In FIG. 10, the off-axis optical system includes an optical path 94 of the laser beam from the VCSEL 1 to the concave mirror 2 (the optical path indicated by a broken line), and an optical path 95 from the concave mirror 2 to the eyeball 30 or the cornea 32 (the optical path indicated by the dashed line). ), and an optical path 96 from the cornea 32 to the PSD 3 (the optical path indicated by a two-dot chain line). By intersecting the optical path 94 and the optical path 96, the optical path length can be increased.

In the second modification, an example is shown in which the VCSEL 1 is tilted with respect to the normal viewing direction of the eyeball 30 so that the laser beam emitted perpendicularly to the exit surface is incident near the center of the concave mirror 2. In this modification, a triangular prism 56 is provided between the VCSEL 1 and the concave mirror 2, and by deflecting the laser beam emitted from the VCSEL 1, the laser beam emitted perpendicularly to the exit surface is directed to the center of the concave mirror 2. It is injected into the vicinity. Here, the triangular prism 56 is an example of a "deflection means". However, the deflection means is not limited to the triangular prism 56, but may be a diffraction grating or the like.

Furthermore, in the second modification example, an example was shown in which the VCSEL 1 and PSD 3 are mounted on the FFC 52, but in this modification example, since the VCSEL 1 and the PSD 3 can be arranged in the same plane, the FPC 57 fixed to the element support 50 can be mounted. VCSEL1 and PSD3 are mounted on the . This facilitates power supply and peripheral circuit mounting. In FIG. 10, an FPC 57 is fixed to one side of the element support 50, and an FPC 51 on which a battery 53 and a circuit group 55 are mounted is fixed to the opposite side of the element support 50 to the side to which the FPC 57 is fixed. There is. FPC51 and FPC57 are electrically connected by FFC52. The FPCs 51 and 57 are each an example of an "electronic board".

(Fourth modification)
FIG. 11A is a diagram (part 4A) illustrating an example of the configuration of a main part of the pupil position detection device according to the fourth modification. (a) is a view of the main part viewed from above (positive Y direction), (b) is a view of part B (encircled by a dashed line) in (a) viewed from the eyeball side (positive X direction) It is.

In this modification, a package 59, a battery 53, and a circuit group 55 are mounted on a circuit board 58 fixed to the eyeglass frame 22. Moreover, the package 59 includes a cover glass 59a and a support frame 59b, and houses and seals the VCSEL 1 and PSD 3 therein.

By accommodating the VCSEL 1 and the PSD 3 in one package 59, it becomes possible to arrange the VCSEL 1 and the PSD 3 in close proximity. Further, by mounting the package 59, the battery 53, and the circuit group 55 on one circuit board 58, the module including the package 59, the battery 53, and the circuit group 55 can be downsized.

Furthermore, it is also possible to include a wireless transmission circuit in the circuit group 55 to wirelessly connect the module to an external terminal such as a smartphone or a tablet. Thereby, the detection signal of the PSD 3 can be wirelessly transmitted to an external terminal, and the external terminal can be operated and pupil position data can be collected.

In FIG. 11A, the circuit group 55 includes a light emission drive circuit, a detection signal amplification and extraction circuit, a pupil position calculation circuit, a wireless transmission circuit, and the like in order to realize the functional configuration of FIG. In addition, there are various functions that can be integrated, such as an interface circuit with external hardware, a memory recording circuit, a sensor circuit such as an acceleration sensor that determines the direction of the irradiated surface, and a feedback circuit that controls the operation of the light emission drive circuit. Implement. Here, the Y direction in FIG. 11A is an example of the "longitudinal direction of the glasses-shaped support". Further, as an example of the "longitudinal direction of the spectacle-shaped support", it can also be referred to as the direction connecting the ear and nose when a human wears the spectacle-shaped support.

FIG. 11B is a diagram (4B) illustrating an example of the configuration of a main part of the pupil position detection device according to the 4B modification. (a) is a view of the main part viewed from above (positive Y direction), (b) is a view of part B (encircled by a dashed line) in (a) viewed from the eyeball side (positive X direction) , (c) are views of portion B in (a) viewed from the side opposite to the eyeball (negative X direction).

In this modification, a circuit board 58 is fixed inside the eyeglass frame 22, a package 59 containing the VCSEL 1 and PSD 3 is arranged on the eyeball side, and a battery 53 and a circuit group 55 are arranged on the opposite side from the eyeball. . That is, it has the structure of a double-sided circuit board. Moreover, the package 59 includes a cover glass 59a and a support frame 59b, and houses and seals the VCSEL 1 and PSD 3 therein. Further, the opening on the outside side is provided with a cover structure made of a resin material of the same color as the eyeglass frame 22. Here, the X direction in FIG. 11B is an example of the "thickness direction of the glasses-shaped support". Further, as an example of the "thickness direction of the glasses-type support", it can also be referred to as a direction perpendicular to the direction connecting the ears and nose and the normal viewing direction when a person wears the glasses-type support.

Although FIG. 11B describes an example in which the circuit board 58, package 59, circuit group 55, and battery 53 are completely embedded in the eyeglass frame 22, these may be partially embedded. Furthermore, the circuit group 55 does not have to be configured completely on the back side of the package 59.

By using such a configuration, it is possible to eliminate the protrusion of the package 59 portion and the dent of the circuit board installation portion, and to achieve an appearance comparable to that of a normal eyeglass frame. Further, by adopting a double-sided substrate configuration, the installation space of the present pupil position detection device can be reduced.

(Fifth modification)
FIG. 12 is a diagram (part 5) illustrating an example of the configuration of main parts of the pupil position detection device according to the fifth modification.

The pupil position detection device according to this modification includes a plane mirror 2 a that reflects the laser beam emitted from the VCSEL 1 toward the concave mirror 2 . The off-axis optical system includes optical paths 97a and 97b of the laser beam from the VCSEL 1 to the concave mirror 2 (the optical path indicated by the broken line), and an optical path 98 from the concave mirror 2 to the eyeball 30 or the cornea 32 (the optical path indicated by the dashed-dotted line). , and an optical path 99 from the cornea 32 to the PSD 3 (the optical path indicated by a two-dot chain line). The laser light emitted from the VCSEL 1 is incident on the eyeball 30 after reciprocating in the space in front of the eye.

By providing the plane mirror 2a, the optical path length from the VCSEL 1 to the concave mirror 2 can be increased. Some advantages of increasing the optical path length will be explained. First, it is possible to widen the beam diameter of the laser light reaching the focusing and reflecting means. By controlling the wavefront of laser light with the beam diameter widened, the degree of freedom in designing optical systems and optical elements, such as the adoption of aspherical shapes and anisotropic shapes (anamorphic aspherical surfaces, etc.), can be improved. Can be done. Second, it is possible to shorten the distance from the focusing reflection means provided at the final stage of the folded optical system to the eyeball, which is the irradiated surface. In other words, even if the angle of the laser beam incident on the focusing and reflecting means is small, by adjusting the optical path length until it reaches the focusing and reflecting means, a small beam diameter can be obtained at the irradiated surface and the PSD receiving surface. be able to. Thirdly, the change in the position of the beam spot on the PSD light receiving surface, which depends on the eyeball line angle, can be controlled by the optical path length. By designing the optical path length so that the size of the PSD light-receiving surface matches the measurement range of the eyeball line angle, a pupil position detection device having a desired viewing angle and angular resolution can be realized.

Note that the planar mirror 2a and the concave mirror 2 may be arranged in reverse. Further, a second concave mirror may be provided in place of the plane mirror 2a. However, as explained in FIG. 3, the radius of curvature of the concave mirror 2 and the arrangement of the plane mirror 2a and the concave mirror 2 should be adjusted appropriately so that the laser beam after being reflected by the eyeball 30 or cornea 32 becomes parallel light. It is preferable to

(Sixth variation)
The pupil position detection device according to the sixth modification includes a position adjustment means 131 that adjusts the position of the concave mirror 2, and an inclination adjustment means 132 that adjusts the inclination.

FIG. 13 is a diagram (part 6) illustrating an example of the configuration of the main parts of the pupil position detection device according to the present modification, in which (a) is a diagram of the concave mirror 2 viewed from the direction facing the concave surface; b) is a diagram showing a cross section taken along line AA' in (a).

As shown in FIG. 13(a), the position adjustment means 131 has push screws 131a, 131b, and 131c, and a frame portion 131d, and each of the push screws 131a to 131c has three points on the side surface of the concave mirror 2. It constitutes a three-point support mechanism that supports the By moving each of the push screws 131a to 131c back and forth independently, the position in the YZ plane and the inclination in the YZ plane can be changed.

Further, as shown in FIG. 13(b), the inclination adjusting means 132 includes a substrate 132a, a spring 132b, and a push screw 132c. The substrate 132a is a plate-like member having a flat portion along the YZ plane, and a protrusion 133 is formed at the center of the flat portion. The tip of the protrusion 133 in the negative X direction is in contact with a surface included in the frame 131d of the position adjustment means 131 on the negative X direction side.

The springs 132b are provided at two locations on the substrate 132a in the Y direction, and each applies a negative biasing force to the concave mirror 2 in the X direction. Further, the substrate 132a and the frame portion 131d are connected by a spring 132b.

The push screw 132c is provided at one location in the Y direction. By moving the push screw 132c back and forth in the negative X direction and pushing the concave mirror 2 through the frame 131d, the concave mirror 2 is moved in the out-of-plane direction of the YZ plane using the lever principle using the tip of the projection 133 as a fulcrum. It can be tilted (made to speak).

In order to more finely adjust the inclination of the concave mirror 2 in the out-of-plane direction of the YZ plane, the two locations where the springs 132b are provided are preferably located as far apart as possible in the Y direction. Similarly, the location where the push screw 132c is provided is preferably close to the end of the substrate 132a in the Y direction.

Here, a mechanism has been described in which a push screw 132c is provided at one location in the Y direction to tilt the concave mirror 2 around the Z axis. However, a push screw 132c is also provided at one location in the Z direction to tilt the concave mirror 2 around the Y axis. It may also be possible to tilt it.

In this modification, the position and inclination of the laser beam irradiated from the concave mirror 2 toward the eyeball 30 or the cornea 32 can be adjusted using the position adjustment means 131 and the inclination adjustment means 132.

Although FIG. 13 shows means for adjusting the position and inclination of the concave mirror 2, even when an optical element such as a diffraction element is provided in place of the concave mirror 2, the position and inclination of the optical element can be adjusted using the same adjustment means. Can be adjusted.

(Seventh modification)
FIG. 14 is a diagram (Part 7) illustrating an example of the configuration of the main parts of the pupil position detection device according to the seventh modification. (a) is a view of the main part viewed from above (positive Y direction), (b) is a view of part C (encircled by a dashed line) in (a) viewed from the eyeball side (positive X direction) It is.

As shown in FIG. 14, the pupil position detection device according to this modification includes a light guiding means 150 arranged between the VCSEL 1 and the concave mirror 2 in front of the eyes of a person wearing the glasses-type support 20. The light guiding means 150 can guide the laser beam emitted from the VCSEL 1 to the concave mirror 2 by causing light to propagate inside.

The light guiding means 150 is, for example, a transparent cylindrical member. The light emitted from the VCSEL 1 enters the inside of the light guiding means 150 from the end surface of the light guiding means 150 in the negative X direction, passes through the inside, and is formed at the end surface of the light guiding means 150 in the positive X direction. The light is incident on the reflective curved surface 150a. The reflective curved surface 150a is a surface that functions as a concave mirror, and can reflect the incident laser light and irradiate the eyeball 30 with a focused laser light.

Note that "transparent" of the light guiding means 150 means that it is transparent to visible light and light emitted from the VCSEL 1. By making it transparent to visible light, a person wearing the glasses-type support 20 can see what is ahead without being obstructed by the light guiding means 150. Furthermore, by making the light emitted from the VCSEL 1 transparent, it is possible to reduce loss due to light absorption and propagate the light inside. Note that the light guiding means 150 is not limited to a cylindrical member, and may have any cross-sectional shape as long as it is a columnar member.

As shown in FIG. 14, the light guiding means 150 is supported by a light guiding means support 151. Further, the light guide means support 151 is fixed to a circuit board support 58a that supports a circuit board 58 on which the VCSEL 1, PSD 3, etc. are mounted. Therefore, the VCSEL 1, the concave mirror 2, and the PSD 3 are supported as an L-shaped structure in a fixed positional relationship.

The light guiding means support 151 and the circuit board support 58a can rotate in the direction of the outer periphery of the cylindrical shape, and can also move forward and backward in the direction of the optical axis. This makes it possible to adjust the position at which the laser beam reflected by the reflective curved surface 150a at the end of the light guiding means 150 enters the eyeball 30 or the cornea 32.

Note that an opening is provided in the light guiding means support 151 so that the positions of the VCSEL 1 and the PSD 3 mounted on the circuit board 58 do not change as the position of the light guiding means supporting body 151 is adjusted.

In the pupil position detecting device according to this modification, the optical elements such as the VCSEL 1, the light guiding means 150, and the PSD 3 can be integrated, so that the pupil position detecting device can be downsized.

(Eighth modification)
The pupil position detection device according to the eighth modification includes a non-coaxial concave mirror 2b instead of the concave mirror 2.

FIG. 15 is a diagram illustrating an example of the configuration of the non-coaxial concave mirror 2b. The non-coaxial concave mirror 2b includes a shape that is axially symmetrical with respect to the central axis D shown by a broken line in FIG. Including shape.

More specifically, as shown in FIG. 15, the non-coaxial concave mirror 2b includes a curved surface 2b1 and a curved surface 2b2 at symmetrical positions across the central axis D, and a center of curvature 2b21 of the curved surface 2b1 and a curved surface 2b2. The center of curvature 2b22 of is located at a position shifted in the direction intersecting the central axis D. Note that the curved surface 2b1 and the curved surface 2b2 may each be a spherical surface or an aspherical surface.

By optimizing the shapes of the curved surfaces 2b1 and 2b2 of the non-coaxial concave mirror 2b, the laser beam reflected by the eyeball 30 or the cornea 32 can be converted into a non-diffracted beam and propagated to the PSD 3. An example of the non-diffracted beam is a Bessel beam having a concentric beam profile.

FIG. 16 is a diagram illustrating an example of a undiffracted beam. The diverging laser beam emitted from the VCSEL 1 is converted into a focused laser beam by the non-coaxial concave mirror 2b, and enters the eyeball 30 or cornea 32.

In the non-coaxial concave mirror 2b of FIG. 16, the laser beam L3 shown by a solid line and the laser beam L4 shown by a broken line are two beams having slightly different angles after being reflected by the eyeball 30 or the cornea 32 when viewed in a two-dimensional plane. They propagate as two parallel laser beams (in an actual three-dimensional space, the projected components on the optical axis have the same size, and the light rays have wave number vectors of the same size pointing inward in the same radial direction).

Such a laser beam has a beam profile in the shape of a Bessel function in the diagonally hatched area of FIG. 16 as a result of interference by light of wave number vector components opposite to the optical axis. Furthermore, the beam can be propagated over a long distance in the optical axis direction without changing its diameter.

The mounting position of the PSD 3 can be made robust by making the laser beam L5 (hatched portion) incident on the light receiving surface of the PSD 3 a non-diffracted beam. Note that the formation region of the non-diffracted beam may be a position before the laser beam is reflected by the eyeball 30. In this case, robustness with respect to the position of the spectacle-shaped support 20 can be improved.

(9th modification)
The pupil position detection device according to this modification includes a HOE (Holographic Optical Device) 2b instead of the concave mirror 2. Here, the HOE2b is an example of a "diffractive reflective optical element."

FIG. 17A is a diagram illustrating an example of the configuration of an off-axis optical system using an HOE. FIG. 2 is a diagram illustrating a case in which a focused laser beam is generated. Here, the HOEs 2b and 2c are each an example of a "focusing reflection means" and an example of a "diffraction type reflection means."

The HOE can reflect light incident perpendicularly to the surface in an inclined direction. Therefore, as shown in FIG. 17A(a), the HOE 2b can be placed with its plane portion facing the exit surface of the VCSEL 1 while irradiating the eyeball 30 with laser light. This facilitates positioning during mounting. Furthermore, since the HOE 2b can be made thin, the pupil position detection device can be downsized.

Moreover, a plurality of focused laser beams can be generated from the laser beam emitted by one light emitting part of the VCSEL 1, and a plurality of positions of the eyeball 30 can be irradiated with the focused laser beams at the same time. FIG. 17A(b) shows an example in which three focused laser beams are generated by the 0th-order light L90, +1st-order diffracted light L91, and −1st-order diffracted light L92 by the HOE 2d.

In FIG. 2, it has been explained that the detection range is expanded by shifting the light emitting part of the VCSEL 1 in response to a large rotational movement of the eyeball 30, but in this modification, the number of focusing positions by one light emitting part of the VCSEL 1 is set to three. be able to. Thereby, even if the eyeball 30 makes a larger rotational movement, the laser beam reflected by the eyeball 30 or the cornea 32 can be prevented from deviating from the light receiving surface of the PSD 3, and the detection range of the rotational angle can be expanded. .

Note that in addition to the HOE, a diffractive optical element (DOE) element or a Fresnel lens can be used.

(10th modification)
The pupil position detection device according to this modification includes, in place of the concave mirror 2, a first reflective condensing element 200 having a liquid crystal part 202 filled with an anisotropic molecular material. Here, the anisotropic molecular material refers to a liquid crystal material and the like.

FIG. 17B is a diagram illustrating an example of the configuration of an off-axis optical system using the first reflective condensing element 200. As shown in FIG. 17B, the first reflective condensing element 200 includes a support substrate 201, a liquid crystal section 202, and a quarter wavelength shift section 203. Here, the first reflective condensing element 200 is an example of a "focusing reflection means", and the liquid crystal section 202 is an example of an "encapsulating section".

The linearly polarized light emitted from the VCSEL 1 is converted into circularly polarized light by the quarter wavelength shift section 203 and enters the liquid crystal section 202 . The light reflected by the liquid crystal section 202 toward the eyeball 30 passes through the quarter wavelength shift section 203 in the opposite direction, is converted into linearly polarized light again, and enters the corneal surface of the eyeball 30 . Thereafter, the light reflected on the corneal surface enters the PSD 3.

Further, as shown in FIG. 17C, the liquid crystal section 202 includes a support substrate 2021, an alignment film 2022, an alignment film 2023, and a transmission support substrate 2024 that transmits light.

The space inside the film formed by the alignment film 2022 and the alignment film 2023 contains liquid crystal molecules 2025. The liquid crystal molecules 2025 are spirally arranged in a direction perpendicular to the planes of the alignment films 2022 and 2023.

The alignment of liquid crystal molecules 2025 is spatially controlled by alignment films 2022 and 2023. Specifically, the inside of each of the alignment films 2022 and 2023 is divided into minute spatial regions, and each region is irradiated with UV light polarized in a specific direction to perform optical alignment. The alignment of liquid crystal molecules 2025 in each minute spatial region is controlled.

In other words, the liquid crystal molecules 2025 are oriented to form a three-dimensional quasi-periodic structure inside the liquid crystal section 202. Here, the quasi-periodic structure refers to a structure in which the structural period or its phase is spatially adjusted so as to exhibit light-gathering properties.

From the right to the left in FIG. 17C, the light incident on the liquid crystal section 202 passes through the transparent support substrate 2024 and the alignment film 2023, is reflected by the action of the liquid crystal molecules 2025, and then passes through the alignment film 2023 and the transmission support substrate 2024. The light passes through in the opposite direction to the forward direction and is emitted from the liquid crystal section 202.

In the example of FIG. 17C, by adjusting the orientation direction on the surface of the alignment film 2022 or 2023 corresponding to the starting position of the helical structure by the liquid crystal molecules 2025, the equiphase plane 2026 of the curve representing the helical structure is aligned with the incident direction of light. It is curved in a concave shape. Thereby, the liquid crystal molecules 2025 function as a lens, and the light reflected by the action of the liquid crystal molecules 2025 and traveling to the right in the figure can be focused. Since a known technique (for example, see Nature Photonics Vol. 10 (2016) p. 389) can be applied to the technique of making liquid crystal molecules function as an optical element such as a lens, further detailed explanation will be omitted here. Note that in FIG. 17B, 2027 indicated by a dashed dotted line indicates light that enters the liquid crystal section 202, and 2028 indicated by a dashed double dotted line indicates light reflected by the liquid crystal section 202 and condensed.

Next, the optical characteristics of the liquid crystal section 202 will be further described with reference to FIG. 17D. FIGS. 17D (a) and (b) show a liquid crystal section 202 that focuses right-handed circularly polarized light. The liquid crystal section 202 has different reflection or transmission characteristics for right-handed polarized light and left-handed polarized light, depending on the rotation direction of the liquid crystal molecules 2025.

In FIG. 17D(a), light that has been converted into circularly polarized light by the quarter wavelength shifter 203 is incident on the liquid crystal section 202. In FIG. The light reflected by the liquid crystal section 202 is returned to linearly polarized light by passing through the quarter-wave plate again in the opposite direction, and is irradiated onto the eyeball 30. In order to reduce the penetration of laser light into the eyeball 30 as much as possible, the linearly polarized light is preferably S-polarized light having an electric field vibration plane in a direction perpendicular to the plane of the drawing.

On the other hand, FIG. 17D(b) shows an example in which the light beam from the VCSEL 1 is randomly polarized light without polarization control. Of the randomly polarized light incident on the liquid crystal section 202, only the right-handed circularly polarized light is reflected by the support substrate 2021 and collected, passes through the quarter wavelength shift section 203, and is converted into linearly polarized light. On the other hand, the left-handed polarized light component passes through the support substrate 201 as it is and is not irradiated onto the corneal surface.

In the pupil position detection device according to this modification, the three-dimensional alignment distribution of the liquid crystal molecules 2025 can be controlled by two-dimensional alignment control of the alignment films 2022 and 2023, and as a result, the reflection and diffraction efficiency is high, and the thin The first reflective condensing element 200 can be provided. Further, it is possible to impart polarization selectivity to the first reflective condensing element 200, and it is possible to provide a pupil position detection device that reduces the number of optical components and ensures eye safety against laser light.

(11th modification)
The pupil position detection device according to this modification includes a second reflective condensing element 210 containing an anisotropic molecular material.

FIG. 17E is a diagram illustrating an example of the configuration of an off-axis optical system using the second reflective condensing element 210. As shown in FIG. 17E, the second reflective condensing element 210 includes a liquid crystal section 211, a light guiding means 212, and a quarter wavelength shift section 213. Here, the second reflective condensing element 210 is an example of a "focusing reflection means", and the liquid crystal section 211 is an example of an "anisotropic molecular material section".

The liquid crystal section 211 is provided so as to be in contact with the light guiding region interface of the light guiding means 212. Inside the liquid crystal section 211, like the liquid crystal section 202 described above, liquid crystal molecules are oriented to form a three-dimensional quasi-periodic structure inside the liquid crystal section 211.

The light emitted from the VCSEL 1 is coupled into the light guiding means 212 via the slope of the incident end of the light guiding means 212. Although it may be coupled into the light guiding means 212 via a grating, in consideration of the simplicity and accuracy of mounting, it is preferable to arrange the mounting board surface of the VCSEL 1 and the light guiding means 212 at right angles. .

The light coupled into the light guiding means 212 undergoes repeated total reflection at the interface of the light guiding means 212 and propagates inside the light guiding means 212 to the vicinity in front of the eyes. Of the light internally propagated through the light guiding means 212, right-handed circularly polarized light or left-handed circularly polarized light is selectively reflected by the liquid crystal section 211 and condensed by the lens function of the liquid crystal section 211, and the light is focused at 1/4 wavelength. After being converted into linearly polarized light (S-polarized light) by the shift unit 213, the corneal surface of the eyeball 30 is irradiated with the light.

Note that when using the light guiding means 212, it is difficult to irradiate the corneal surface with light at a shallow angle, so the light is reflected by the liquid crystal section 211 near the front of the eyeball 30. In this case, in order to make the light enter the PSD 3, it is necessary to condense the light at a position (specular reflection position) shifted toward the PSD 3 from the pupil center position on the cornea.

In the pupil position detection device according to this modification, the light emitted from the VCSEL 1 can be irradiated onto the corneal surface after securing the optical path length within the light guiding means 212, so that the device can be miniaturized. Further, by using the same casing configuration as in FIG. 14, the VCSEL 1, the light guiding means 212, the PSD 3, etc. can be configured integrally.

[Second embodiment]
Next, a retinal projection display device according to a second embodiment will be described with reference to FIG. 18.

FIG. 18 is a diagram illustrating an example of the configuration of a retinal projection display device according to this embodiment.

The retinal projection display device 60 includes an RGB (Red, Green, Blue) laser light source 61, a scanning mirror 62, a plane mirror 63, a half mirror 64, an image generation section 65, and a pupil position detection device 10.

The RGB laser light source 61 temporally modulates and outputs laser light of three colors of RGB. The scanning mirror 62 two-dimensionally scans the light from the RGB laser light source 61. The scanning mirror 62 is a MEMS mirror or the like. However, the present invention is not limited to this, and any mirror that has a reflecting part that scans light, such as a polygon mirror or a galvano mirror, may be used. MEMS mirrors are advantageous in terms of size and weight reduction. Note that the driving method of the MEMS mirror may be any of electrostatic, piezoelectric, electromagnetic, and the like.

The plane mirror 63 reflects the scanning light from the scanning mirror 62 toward the half mirror 64 . The half mirror 64 transmits a portion of the incident light and reflects a portion toward the eyeball 30 . The half mirror 64 has a concave curved shape, focuses the reflected light near the pupil 31 of the eyeball 30, and forms an image at the position of the retina 33. As a result, an image formed by the scanning light is projected onto the retina 33. Light 61a indicated by a broken line in the figure represents light that forms an image on the retina 33. Note that in the half mirror 64, the amount of reflected light and transmitted light does not necessarily have to be one to one.

The pupil position detection device 10 detects the position of the pupil 31 according to eye movement, and transmits a feedback signal of the position of the pupil 31 to the image generation unit 65.

The image generation unit 65 has a deflection angle control function of the scanning mirror 62 and a light emission control function of the RGB laser light source 61. The image generation unit 65 also receives a feedback signal of the position of the pupil 31 from the pupil position detection device 10. According to the position of the pupil 31 detected by the pupil position detection device 10, the deflection angle of the scanning mirror 62 and the light emission of the RGB laser light source 61 are controlled, and the projection angle of the image or the image content is rewritten. Thereby, it is possible to form an image on the retina 33 that follows (eye tracking) the change in the position of the pupil 31 due to eyeball movement.

In the above description, an example is shown in which the retinal projection display device 60 is a head mounted display (HMD), which is a wearable terminal. However, the retinal projection display device 60 as a head-mounted display is one that is not only attached directly to a person's head, but also one that is indirectly attached to a person's head via a member such as a fixing part. It may also be a head-mounted display device). Alternatively, a binocular retinal projection display device may be used, in which a pair of retinal projection display devices 60 are provided for left and right eyes.

[Comparison between the pupil position detection device according to the embodiment and the device described in Patent Document 1]
Here, the device described in Patent Document 1 and the pupil position detection device 10 according to the embodiment will be compared. FIG. 19 is a diagram showing the configuration of an eye tracking device described in Patent Document 1.

In the device described in Patent Document 1, a laser light source is used, the laser light is scanned by a MEMS mirror, and the incident angle of the light to the eyeball is changed. In contrast, in the embodiment, a VCSEL having a plurality of light emitting parts is used as a light source, and the incident angle of light to the eyeball is changed by changing the light emitting parts of the VCSEL. In the embodiment, the angle of incidence of light on the eyeball is changed in this way without using a movable part. Therefore, compared to a structure having a movable part, it is stronger against vibrations, external shocks, etc.

In the device described in Patent Document 1, a photodetector detects the reflected light intensity of the light irradiated to the cornea, whereas in the embodiment, a PSD is used to detect the light reflected by the eyeball and incident on the light receiving surface of the PSD. Detect the position of. PSD detects the position of the incident light without depending on the light intensity, so even if there is a difference in the amount of reflected light due to the position of light reflection on the eyeball, etc., the PSD can detect the position of the incident light without being affected by the difference in the amount of reflected light. Sensitive position detection is possible. As a result, the tilted position of the eyeball, such as the pupil, can be detected with high precision.

In the embodiment, a light emitting drive unit 110 is provided, and the light emitting drive unit 110 shifts the positions of the light emitting parts of the VCSEL and the light emission timing between the light emitting parts and lights them up individually. This allows coarse movements of the eyeballs to be captured so that reflected light from the eyeballs falls on the light-receiving surface of the PSD, and minute movements of the eyeballs can be captured by position detection using the PSD.

In the device described in Patent Document 1, the eyeball position is estimated from two peak intensities (reflection positions on the cornea at two points) on the time axis of light reflected by the eyeball. In the embodiment, the eyeball position is estimated based on the reflection position of one point on the eyeball, such as the cornea. Therefore, the VCSEL and PSD do not necessarily have to be in symmetrical positions. In embodiments, the PSD may not be placed near the specular (specular) angle of the eye, but may be placed on the same side as the VCSEL.

Although examples of embodiments of the present invention have been described above, the present invention is not limited to such specific embodiments, and various modifications may be made within the scope of the gist of the present invention as described in the claims. It is possible to transform and change.

Further, information on the pupil position detected by the pupil position detection device 10 can also be used for eye tracking in an input device of an electronic device. For example, the output of the pupil position detection device 10 shown in FIG. 1 may be used for eye tracking as input information to an electronic device. This makes it possible to realize eye tracking that is robust against head position deviations and the like.

It can also be used in optometry equipment that has the function of detecting the tilt of the eyeball and the position of the pupil (cornea). An optometry device refers to a device that can perform various tests such as a visual acuity test, an eye refractive power test, an intraocular pressure test, and an axial length test. An optometry device is a device that can perform eye examinations without contacting the eyeballs, and includes a support part that supports the subject's face, an optometry window, and a display that keeps the subject's eyeball direction (direction of line of sight) constant during the eye exam. It has a display section, a control section, and a measurement section. In order to improve the measurement accuracy of the measurement unit, the test subject is required to stare at a single point without moving his or her eyes (line of sight), and the subject fixes his or her face on the support and stares at the object displayed on the display through the optometry window. . At this time, when detecting the tilt position of the eyeball, the eyeball tilt position detection device of this embodiment can be used. The eyeball tilt position detection device is placed on the side of the measurement unit so as not to interfere with the measurement. The eyeball tilt position (line of sight) information obtained by the eyeball tilt position detection device can be fed back to the control unit, and measurements can be made in accordance with the eyeball tilt position information.

1 VCSEL (an example of light source means)
2 Concave mirror (an example of focusing reflection means)
2a Plane mirror 2b Non-coaxial concave mirror (an example of focusing reflection means)
2c, 2d HOE (an example of a focusing reflection means, an example of a diffractive reflection means)
3 PSD (an example of position detection means)
10 Pupil position detection device 20 Eyeglass type support 21 Eyeglass lens 22 Eyeglass frame 30 Eyeball (an example of irradiated surface)
31 Pupil 32 Cornea 33 Retina 50 Element support 51 FPC (an example of a drive board)
52 FFC (an example of a drive board)
53 Battery 54 Connector 55 Circuit group 56 Triangular prism (an example of deflection means)
57 FPC
58 Circuit board 59 Package 60 Retinal projection display device 61 RGB laser light source 62 Scanning mirror 63 Plane mirror 64 Half mirror 65 Image generation unit 90 Reference illuminated surface 100 Processing unit 101 CPU
102 ROM
103 RAM
104 SSD
105 Light source drive circuit 106 A/D conversion circuit 107 Input/output I/F
110 Light emission drive unit 111 Detection signal input unit 120 Calculation unit (an example of calculation means)
121 Eyeball rotation angle estimation section 122 Pupil position acquisition section 130 Pupil position output section 131 Position adjustment means 132 Tilt adjustment means 150 Light guide means 151 Light guide means support

US2016/0166146 US2017/0276934

Claims (26)

a light source means for emitting light;
a focusing and reflecting means that focuses the light from the light source means and reflects it toward the eyeball ;
a position detection means for detecting the position of the reflected light from the eyeball ,
The focusing reflection means has a curvature determined to offset the divergence of the reflected light from the eyeball.
optical equipment. 2. The optical device according to claim 1, wherein the light before reaching the eyeball is propagated by being propagated at least once before reaching the eyeball . The distance between the focusing reflection means and the eyeball is d1,
The diameter of the effective area of the focusing reflection means is Dm,
The radius of curvature in the eyeball is rc,
The wavelength of the light from the light source means is λ,
When the radius of the light beam on the light receiving surface of the position detection means is hUL, the following formula is satisfied.

The optical device according to claim 1 or 2. 4. The optical device according to claim 1, wherein the optical path from the light source means to the focusing and reflecting means intersects the optical path from the eyeball to the position detecting means. 5. The optical device according to claim 4, further comprising a deflecting means for deflecting the light from the light source means on the optical path from the light source means to the focusing and reflecting means. 4. The optical device according to claim 1, wherein the optical path from the light source means to the focusing and reflecting means is parallel to a predetermined reference plane in contact with the eyeball . the light source means;
the position detection means;
7. The optical device according to claim 1, further comprising a support body that supports an electrical equipment board on which a light source driving circuit for driving the light source means is mounted. The focusing reflection means includes:
A direction parallel to a plane including an optical axis of light propagating from the focusing reflection means to the eyeball and an optical axis of light propagating from the eyeball to the position detection means, and a direction perpendicular to the plane. The optical device according to any one of claims 1 to 7, comprising surfaces having different curvatures in different directions. 9. The optical device according to claim 1, further comprising at least one of a position adjusting means for adjusting the position of the focusing and reflecting means, and an inclination adjusting means for adjusting the inclination of the focusing and reflecting means. 10. Any one of claims 1 to 9, further comprising a light guiding means disposed between the light source means and the focusing/reflecting means to propagate the light from the light source means to the focusing/reflecting means. Optical device as described in section. 11. The optical device according to claim 10, wherein the focusing and reflecting means is formed on one end surface of the light guiding means. 12. The optical device according to claim 1, wherein the focusing and reflecting means includes a non-coaxial concave mirror. 12. The optical device according to claim 1, wherein the focusing reflection means includes a diffractive reflection means. 14. The optical device according to claim 13, wherein the diffractive reflecting means irradiates light to a plurality of positions on the eyeball . The optical path from the light source means to the eyeball is longer than the optical path from the time it is reflected by the eyeball to the time the optical path is incident on the position detection means.
The optical device according to any one of claims 1 to 14. a light source means for emitting light;
a focusing and reflecting means that focuses the light from the light source means and reflects it toward the eyeball;
a position detection means for detecting the position of the reflected light from the eyeball,
The diameter of the light incident on the position detection means is less than or equal to the diameter of the light incident on the focusing reflection means.
optical equipment. A retinal projection display device comprising the optical device according to any one of claims 1 to 16 . A head-mounted display device comprising the optical device according to claim 1 . An optometry device comprising the optical device according to any one of claims 1 to 16 . The focusing reflection means includes an enclosure in which an anisotropic molecular material is enclosed,
12. The optical device according to claim 1, wherein the anisotropic molecular material is oriented to form a three-dimensional quasi-periodic structure inside the enclosure. The focusing reflection means includes:
comprising: a light guiding means for internally propagating light from the light source means; and an enclosing part provided in contact with a light guiding region interface of the light guiding means and encapsulating an anisotropic molecular material;
11. The optical device according to claim 1, wherein the anisotropic molecular material is oriented to form a three-dimensional quasi-periodic structure inside the enclosure. 22. The optical device according to claim 1, wherein the focusing and reflecting means and the position detecting means are arranged in angular directions that are symmetrical with respect to the normal direction of the eyeball . The light source means, the focusing reflection means, and the position detection means each have an optical axis of light propagating from the focusing reflection means to the eyeball , and an optical axis of light propagating from the eyeball to the position detection means, is placed in a plane containing
The light source means and the focusing reflection means are arranged close to one side with respect to the normal direction of the eyeball ,
22. The optical device according to claim 1, wherein the focusing and reflecting means is arranged on the other side with respect to the normal direction of the eyeball . The light source means, the focusing reflection means , and the position detection means are all arranged in the thickness direction of the eyeglass-type support and arranged on the eyeglass-type support . The optical device according to any one of the above. 20. The light source means, the focusing reflection means, and the position detection means are all arranged in the longitudinal direction of the spectacle- shaped support and arranged on the spectacle-shaped support. 22. The optical device according to any one of Item 21 . The light source means and the position detection means are provided on one surface of the electrical equipment board,
8. The optical device according to claim 7, further comprising, on the other surface of the electrical equipment board, at least one of a light source driving circuit for driving the light source means and an arithmetic means for processing the output from the position detecting means.

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