Eye pad and equipment capable of tracking eye movement

Abstract

The utility model relates to the technical field of eye movement tracking, in particular to an eye pad and equipment capable of tracking eye movement, and the eye pad comprises an eye pad body which is provided with a first position and a second position corresponding to the temples of a user, a third position and a fourth position corresponding to the lower parts of the eyes of the user, and a fifth position corresponding to the nose of the user; the flexible piezoelectric sensor is used for sensing the deformation of the skin during eye movement and outputting a voltage signal, adopts an asymmetric multi-layer structure, adopts a piezoelectric film layer formed by aluminum nitride, and comprises a first sensor, a second sensor, a third sensor and a fourth sensor which are respectively attached to the first position, the second position, the third position and the fourth position; the flexible integrated chip is located at the fifth position and used for processing the voltage signal to track eyeball movement. According to the eye pad and the device capable of tracking the eye movement, integration and miniaturization are achieved while accuracy and real-time performance are guaranteed, and the eye pad and the device have the advantages of being convenient and comfortable to wear.

Description

Technical Field

[0001] The utility model relates to the technical field of eye tracking, in particular to an eye patch and a device capable of eye tracking. Background Art

[0002] Eye tracking technology records the time, position, trajectory and other indicators of eye movement (eye movement) to understand people's acquisition and processing of real-time information. The main forms of eye movement include fixation, smooth pursuit movement, blinking, eye tremor, etc. These eye movement behaviors can provide a lot of valuable information, such as revealing a person's cognitive function, emotional state, eye health and fatigue level.

[0003] Currently, commonly used eye tracking devices are mainly divided into the following three types: devices based on electrooculogram (EOG), devices based on eye video analysis, and devices based on scleral contact lenses (search coil method).

[0004] Among them, the output signal of EOG-based devices is relatively weak and easily affected by the surrounding environment, such as light intensity, and is also easily interfered by muscle electrical signals; devices based on eye video analysis have difficulty tracking eye movements in dark conditions. The enlargement of the pupil and the drooping of eyelashes or eyelids in the dark will cover the pupil, affecting the accuracy of eye tracking; devices based on scleral contact lenses are extremely invasive, easily causing discomfort to the wearer, and are prone to slipping during use, which greatly limits the usage time, generally not exceeding 60 minutes.

[0005] At the same time, most devices require expensive and bulky components, such as a large number of high-resolution cameras, infrared light source settings, power supplies, optical sensors, etc., which makes their miniaturization quite challenging, affecting the convenience of daily wear and limiting application expansion. Utility Model Content

[0006] The technical problem to be solved by the present invention is that the prior art lacks an eye tracking device that is accurate, miniaturized and comfortable to wear. An eye patch and device capable of eye tracking are provided, which achieve integration and miniaturization while ensuring accuracy and real-time performance, and have the advantages of convenience and comfort when worn.

[0007] In the first aspect, in order to solve the above technical problems, the utility model provides an eye patch capable of eye tracking, comprising:

[0008] The eye patch body is configured with a first position and a second position corresponding to the user's temple, a third position and a fourth position corresponding to the user's eyes, and a fifth position corresponding to the user's nose;

[0009] A flexible piezoelectric sensor for sensing skin deformation during eye movement and outputting a voltage signal; the flexible piezoelectric sensor adopts an asymmetric multilayer structure, and uses aluminum nitride to construct a piezoelectric film layer; the flexible piezoelectric sensor comprises a first sensor and a second sensor respectively attached to the first position and the second position, and a third sensor and a fourth sensor respectively attached to the third position and the fourth position;

[0010] A flexible integrated chip is used to process the voltage signal to track the movement of the eyeball; the flexible integrated chip is located at the fifth position.

[0011] In one embodiment of the present invention, according to the distance from the skin, the asymmetric multilayer structure is, from far to near, a first packaging layer, a top electrode layer, an aluminum nitride piezoelectric film layer, a semi-crystalline polymer layer, a bottom electrode layer and a second packaging layer.

[0012] In one embodiment of the present invention, the thickness of the semi-crystalline polymer layer is 20 times the thickness of the aluminum nitride piezoelectric film layer.

[0013] In one embodiment of the present invention, the piezoelectric performance of the aluminum nitride piezoelectric film layer is related to the sputtering conditions; the aluminum nitride piezoelectric film layer is deposited by a low-temperature sputtering technique below 400°C.

[0014] In one embodiment of the utility model, the flexible integrated chip includes a signal amplifier, a filter and a micro signal processor; the signal amplifier amplifies the voltage signal; the filter reduces noise on the amplified voltage signal and then transmits it to the micro signal processor for processing.

[0015] In one embodiment of the present invention, the eye patch body comprises a support layer, an application layer and a release layer;

[0016] The support layer is located on a side of the eye patch body away from the user's skin;

[0017] The pasting layer is used to fix the flexible piezoelectric sensor and the flexible integrated chip; the pasting layer is located between the supporting layer and the release layer; when in use, the release layer is torn off, and the pasting layer can be pasted on the skin surface of the user.

[0018] In one embodiment of the present invention, the support layer is provided with an aluminum nose strip on a side away from the application layer; the aluminum nose strip is used to fix the eye patch body on the nose of the user.

[0019] In one embodiment of the present invention, the application layer is made of a gelatin-based material; and the release layer is a single-layer silicon-sprayed release film.

[0020] In one embodiment of the present invention, wireless transmission is performed between the flexible integrated chip and the computer via Bluetooth.

[0021] In a second aspect, in order to solve the above-mentioned technical problem, the utility model also provides a device capable of eye tracking, including the eye patch capable of eye tracking.

[0022] The above technical solution of the utility model has at least the following advantages compared with the prior art:

[0023] The utility model discloses an eye patch and device capable of eye movement tracking, which adopts a flexible piezoelectric sensor to sense the deformation of the skin during eye movement and output a voltage signal. The asymmetric multi-layer structure is adopted, and the piezoelectric film layer is constructed using aluminum nitride, thereby improving the accuracy and real-time performance of eye movement tracking. No external battery power is required, and integration and miniaturization are achieved. The main body is in the form of an eye patch, which has the advantages of convenience and comfort when worn. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to make the content of the utility model more clearly understood, the utility model is further described in detail below based on specific embodiments of the utility model in combination with the accompanying drawings.

[0025] Figure 1 This is a wearable surface structure diagram of an eye patch capable of eye tracking in an embodiment of the utility model;

[0026] Figure 2 It is a multi-layer structure diagram of the flexible piezoelectric sensor in the embodiment of the utility model;

[0027] Figure 3 It is a side view structural diagram of an eye patch capable of eye tracking in an embodiment of the utility model;

[0028] Figure 4 It is a flow chart of eye tracking in an embodiment of the present utility model.

[0029] Description of the Figures in the Specification:

[0030] S11 first sensor; S12 second sensor; S21 third sensor; S22 fourth sensor;

[0031] S3 flexible integrated chip; S4 aluminum nose clip;

[0032] S5 pasting layer; S6 supporting layer; S7 release layer;

[0033] 111 a first packaging layer; 112 a second packaging layer;

[0034] 121 top electrode layer; 122 bottom electrode layer;

[0035] 13: aluminum nitride piezoelectric film layer; 14: semi-crystalline polymer layer. DETAILED DESCRIPTION

[0036] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments so that those skilled in the art can better understand the present invention and implement it, but the embodiments are not intended to limit the present invention.

[0037] Eye tracking technology records the time, position, trajectory and other indicators of eye movement to understand how people acquire and process real-time information. The main forms of eye movement include fixation, smooth pursuit movement, blinking, eye vibration, etc. These eye movement behaviors can provide a lot of valuable information, such as revealing a person's cognitive function, emotional state, eye health and fatigue level.

[0038] With the development of optical information technology, sensor technology, computer technology, etc., especially the latest progress in wearable technology, such as soft materials, manufacturing technology and electronic chip packaging, the development of eye tracking devices has been greatly promoted, and its application in health care, human-computer interaction and virtual reality has been expanded. Commonly used eye tracking devices are mainly divided into: EOG-based devices, eye video analysis-based devices, and scleral contact lens (search coil method)-based devices.

[0039] (1) EOG-based devices:

[0040] The output signal of EOG is a weak bioelectric signal generated by eye movement, which comes from the potential difference between the positively charged cornea and the negatively charged retina. This difference is due to the different metabolic rates between the retina and the cornea. When the eye moves, the potential around the eye changes accordingly, and the eye movement can be tracked by measuring the potential.

[0041] However, the output signal of EOG is relatively weak and easily affected by the surrounding environment, such as light intensity, and is also easily interfered by muscle electrical signals.

[0042] (2) Devices based on eye video analysis:

[0043] Eye video analysis-based devices are currently the most popular eye tracking technology, which uses the reflection of the pupil and cornea to track eye movements in a non-invasive way through a camera. The camera captures the reflected image after infrared light is irradiated on the eye. Due to the physiological characteristics of the cornea protruding from the surface of the eyeball, the principle of bright pupil and dark pupil is used, and through computer processing, the corneal reflection point is used as the base point of the relative position of the camera and the eyeball. The coordinates of the center of the pupil represent the gaze point position.

[0044] However, eye-based video analysis devices have difficulty tracking eye movements in dark conditions. The enlargement of the pupil in the dark relatively increases the chance of the eyelid covering the pupil. The drooping of eyelashes or eyelids can also cover the pupil, thereby affecting the accuracy of eye tracking.

[0045] (3) Scleral contact lens-based devices:

[0046] Scleral contact lens-based devices record the three-dimensional trajectory of eye movement through electromagnetic induction coils, which is a very accurate eye tracking method, but it is extremely invasive. The electromagnetic coil is composed of a suction ring made of medical silicone that matches the curvature of the corneoscleral limbus and an induction coil made of insulated copper wire buried in the ring.

[0047] However, the invasive nature of scleral contact lens-based devices can easily cause discomfort to the wearer, and they are prone to slipping during use, which greatly limits their usage time, generally not exceeding 60 minutes.

[0048] In addition, most devices require expensive and bulky components, such as a large number of high-resolution cameras, infrared light source settings, power supplies, optical sensors, etc., which makes their miniaturization quite challenging, affects the convenience of daily wear and limits the expansion of applications.

[0049] To solve the above problems, this embodiment provides an eye patch and a device capable of eye tracking.

[0050] Embodiment 1

[0051] This embodiment provides an eye patch capable of eye tracking, including:

[0052] The eye patch body is configured with a first position and a second position corresponding to the user's temple, a third position and a fourth position corresponding to the user's eyes, and a fifth position corresponding to the user's nose;

[0053] A flexible piezoelectric sensor for sensing skin deformation during eye movement and outputting a voltage signal; the flexible piezoelectric sensor adopts an asymmetric multilayer structure, and uses aluminum nitride to construct a piezoelectric film layer; the flexible piezoelectric sensor comprises a first sensor and a second sensor respectively attached to the first position and the second position, and a third sensor and a fourth sensor respectively attached to the third position and the fourth position;

[0054] A flexible integrated chip is used to process the voltage signal to track the movement of the eyeball; the flexible integrated chip is located at the fifth position.

[0055] This embodiment uses a flexible piezoelectric sensor to sense the deformation of the skin during eye movement and output a voltage signal. It adopts an asymmetric multi-layer structure and uses aluminum nitride to construct the piezoelectric film layer, which improves the accuracy and real-time performance of eye tracking. It does not require external battery power supply, and achieves integration and miniaturization. The main body is in the form of an eye patch, which has the advantages of convenience and comfort when worn.

[0056] Next, an eye patch capable of eye tracking described in this embodiment is described in detail:

[0057] 1. Flexible piezoelectric sensor

[0058] The flexible piezoelectric sensor is used to sense the deformation of the skin during eye movement and output a voltage signal; the flexible piezoelectric sensor adopts an asymmetric multilayer structure, and uses aluminum nitride to construct the piezoelectric film layer; the flexible piezoelectric sensor includes a first sensor and a second sensor respectively attached to the first position and the second position, and a third sensor and a fourth sensor respectively attached to the third position and the fourth position;

[0059] Specifically, the flexible piezoelectric sensor can be in conformal contact with the skin without leaving the skin surface, output different voltages for different eye movements such as lateral, vertical, and rotational, has the characteristics of high sensitivity and fast response time, and can achieve long-term real-time tracking of eye movements without calibration; it has the characteristics of self-poweredness and does not require an external battery. By designing it into an ultra-thin form at the micron level, it can be highly integrated and miniaturized.

[0060] Specifically, refer to Figure 1 As shown, the flexible piezoelectric sensor includes a first sensor S11 and a second sensor S12 attached to the user's temple, and a third sensor S21 and a fourth sensor S22 attached under the user's eyes. It does not need to be attached to the eyelids, thus avoiding the more sensitive skin around the eyes and improving wearing comfort.

[0061] It should be noted that the “first sensor S11”, “second sensor S12”, “third sensor S21” and “fourth sensor S22” are only distinguished by their different locations, and their structural materials are the same. In the following description, “the flexible piezoelectric sensor” is used to refer to them collectively.

[0062] Furthermore, the flexible piezoelectric sensor adopts an asymmetric multilayer structure, and uses aluminum nitride (AlN) to construct the piezoelectric film layer;

[0063] Specifically, compared with commonly used piezoelectric materials such as lead zirconate titanate, polyvinylidene fluoride, etc., the aluminum nitride AlN has the advantages of non-toxicity, thermal stability, mechanical stability, chemical stability and complementary metal oxide semiconductor compatibility.

[0064] Specifically, the piezoelectric properties of the AlN piezoelectric thin film layer mainly depend on the sputtering conditions and the electrode material, and the crystallinity of the underlying layer has a significant effect on the c-axis orientation of AlN.

[0065] Optionally, the AlN piezoelectric film layer is deposited by a low-temperature sputtering technique below 400°C.

[0066] It is worth mentioning that compared with organic piezoelectric materials that require additional polarization and mechanical stretching to enhance piezoelectric properties, the AlN piezoelectric film layer deposited by low-temperature sputtering technology greatly reduces the production cost.

[0067] Optional, such as Figure 2 As shown, according to the distance from the skin, the asymmetric multilayer structure is, from far to near, the first packaging layer 111, the top electrode layer 121, the AlN piezoelectric film layer 13, the semi-crystalline polymer layer 14, the bottom electrode layer 122 and the second packaging layer 112;

[0068] When the eyeball moves toward the side of the flexible piezoelectric sensor, the skin bends and planar tensile strain occurs, and the top electrode layer 121 measures a positive potential; when the eyeball moves away from the flexible piezoelectric sensor, the skin flattens and planar compressive strain occurs, and the top electrode layer 121 measures a negative potential; the output voltage of the flexible piezoelectric sensor increases as the degree of skin bending increases. Combined with the different positions of the flexible piezoelectric sensor, different eye movements (such as left and right lateral movements, up and down vertical movements, clockwise and counterclockwise rotation, rapid scanning, etc.) and eyelid movements (such as closure time, blinking frequency, etc.) will generate specific output voltage signal patterns.

[0069] It can be seen that the asymmetric multilayer structure makes the output voltage only undergo positive and negative changes during the process of skin bending and flattening. Compared with the piezoelectric sensor with a symmetrical structure, the output voltage signal of the flexible piezoelectric sensor can be analyzed more accurately and quickly.

[0070] Optionally, the thickness of the semi-crystalline polymer layer 14 is 20 times the thickness of the AlN piezoelectric film layer 13;

[0071] Furthermore, the thickness of the AlN piezoelectric film layer is 1 μm, and the thickness of the semi-crystalline polymer layer 14 is 20 μm;

[0072] Specifically, the 20 μm thick semi-crystalline polymer layer provides good electrical isolation between the top electrode layer 121 and the bottom electrode layer 122 , thereby reducing the risk of short circuit.

[0073] Optionally, the semi-crystalline polymer layer 14 is a semi-crystalline N-polyparaxylene film layer; the semi-crystalline N-polyparaxylene film layer has good flexibility and can improve the crystallinity of the AlN piezoelectric film layer, thereby improving the piezoelectric performance and sensitivity;

[0074] Furthermore, the top electrode layer 121 and the bottom electrode layer 122 are platinum (Pt) electrode layers; the AlN piezoelectric film layer 13 is deposited on the semi-crystalline N-polyparaxylene film layer 14, and considering the lattice mismatch, the Pt electrode layer is selected to promote the c-axis orientation of the AlN piezoelectric film layer 13 to improve the piezoelectric performance.

[0075] Optionally, the first encapsulation layer 111 and the second encapsulation layer 112 are polyimide film layers; the polyimide has the advantages of good thermal stability, mechanical properties, chemical stability, dielectric properties, insulation, adhesion and water resistance.

[0076] Optionally, a brief description of the preparation process of the flexible piezoelectric sensor is given below:

[0077] First, semi-crystalline N-polyparaxylene is deposited on a silicon wafer, and then an AlN film is sputtered using an aluminum target in a mixture of argon and nitrogen. A metal Pt top electrode is deposited by electron beam evaporation. The prepared composite material is then separated from the silicon wafer, and a metal Pt bottom electrode is deposited on the semi-crystalline N-polyparaxylene film by electron beam evaporation, which is then encapsulated with polyimide.

[0078] 2. Eye patch body

[0079] Optional, such as Figure 3 As shown, the eye patch body includes a support layer S6, an application layer S5 and a release layer S7;

[0080] The support layer S6 is located on the side of the eye patch body away from the user's skin; the support layer S6 has a protective and supporting function for the eye patch body;

[0081] The pasting layer S5 is used to fix the flexible piezoelectric sensor and the flexible integrated chip S3; the pasting layer S5 is located between the supporting layer S6 and the release layer S7; when in use, the release layer S7 is torn off, and the pasting layer S5 can be applied to the user's skin surface.

[0082] Optional, such as Figure 3As shown, the support layer S6 is provided with an aluminum nose clip S4 on the side away from the application layer S5; the aluminum nose clip S4 is used to fix the eye patch body on the user's nose.

[0083] Optionally, the support layer S6 is made of polydimethylsiloxane material; the polydimethylsiloxane material is non-toxic and biocompatible.

[0084] Optionally, the application layer S5 is made of a gelatin-based material; the gelatin-based material has non-toxicity, biocompatibility and good air permeability;

[0085] Furthermore, based on the material properties, the patch layer S5 can absorb heat and cool down, which to a certain extent alleviates the temperature rise of the flexible piezoelectric sensor during operation, and greatly reduces the possibility of skin damage after wearing the eye patch capable of eye tracking for a long time.

[0086] Optionally, the release layer S7 is a single-layer silicon-sprayed release film; the single-layer silicon-sprayed release film is non-toxic and biocompatible.

[0087] Specifically, when using the eye patch capable of eye tracking described in this embodiment, first tear off the release film, fix the eye patch body on the user's nose through the aluminum nose clip S4, then slowly unfold the eye patch to both sides of the face, and attach the flexible piezoelectric sensors under the eyes and on the temples in turn to sense and detect the deformation of the skin during eye movement.

[0088] It can be seen that the eye patch capable of eye tracking described in this embodiment has the advantages of convenience and comfort when worn, and is easy to detach after use, without causing discomfort such as pulling and pain to the skin.

[0089] 3. Flexible integrated chips

[0090] Optional, such as Figure 4 As shown, the flexible integrated chip includes a signal amplifier, a filter and a micro signal processor;

[0091] Specifically, the signal amplifier amplifies the voltage signal output by the flexible piezoelectric sensor; the filter reduces the noise of the amplified voltage signal, and then transmits it to the micro signal processor for processing.

[0092] Optional, such as Figure 4 As shown, the flexible integrated chip and the computer perform wireless transmission via Bluetooth; combined with the voltage signal, the computer performs modeling and analysis on the eye movement.

[0093] In summary, this embodiment provides an eye patch capable of eye movement tracking, which uses a flexible piezoelectric sensor to sense the deformation of the skin during eye movement and output a voltage signal. It adopts an asymmetric multi-layer structure and uses aluminum nitride to construct the piezoelectric film layer, which improves the accuracy and real-time performance of eye movement tracking; no external battery power is required, and integration and miniaturization are achieved; the main body is in the form of an eye patch, which has the advantages of convenience and comfort when worn.

[0094] Embodiment 2

[0095] This embodiment provides a device capable of eye tracking, including the eye patch capable of eye tracking.

[0096] For an introduction to an eye tracking device provided in this embodiment, please refer to the above embodiment, and this embodiment will not be described in detail here.

[0097] The eye tracking device provided in this embodiment has the same beneficial effects as the above-mentioned eye patch capable of eye tracking.

[0098] Obviously, the above embodiments are merely examples for the purpose of clear explanation and are not intended to limit the implementation methods. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the implementation methods here. The obvious changes or modifications derived from these are still within the scope of protection of the invention of the utility model.

Claims

1. An eye patch capable of eye tracking, characterized in that: include: The eye patch body is configured with a first position and a second position corresponding to the user's temple, a third position and a fourth position corresponding to the user's eyes, and a fifth position corresponding to the user's nose; A flexible piezoelectric sensor for sensing skin deformation during eye movement and outputting a voltage signal; the flexible piezoelectric sensor adopts an asymmetric multilayer structure, and uses aluminum nitride to construct a piezoelectric film layer; the flexible piezoelectric sensor comprises a first sensor and a second sensor respectively attached to the first position and the second position, and a third sensor and a fourth sensor respectively attached to the third position and the fourth position; A flexible integrated chip is used to process the voltage signal to track the movement of the eyeball; the flexible integrated chip is located at the fifth position.

2. The eye patch capable of eye tracking according to claim 1, characterized in that: According to the distance from the skin, the asymmetric multilayer structure is, from far to near, a first packaging layer, a top electrode layer, an aluminum nitride piezoelectric film layer, a semi-crystalline polymer layer, a bottom electrode layer and a second packaging layer.

3. The eye patch capable of eye tracking according to claim 2, characterized in that: The thickness of the semi-crystalline polymer layer is 20 times the thickness of the aluminum nitride piezoelectric film layer.

4. The eye patch capable of eye tracking according to claim 2, characterized in that: The piezoelectric performance of the aluminum nitride piezoelectric film layer is related to the sputtering conditions; the aluminum nitride piezoelectric film layer is deposited by a low-temperature sputtering technique below 400°C.

5. The eye patch capable of eye tracking according to claim 1, characterized in that: The flexible integrated chip includes a signal amplifier, a filter and a micro signal processor; the signal amplifier amplifies the voltage signal; the filter reduces noise on the amplified voltage signal and then transmits it to the micro signal processor for processing.

6. The eye patch capable of eye tracking according to claim 1, characterized in that: The eye patch body comprises a support layer, an application layer and a release layer; The support layer is located on a side of the eye patch body away from the user's skin; The pasting layer is used to fix the flexible piezoelectric sensor and the flexible integrated chip; the pasting layer is located between the supporting layer and the release layer; when in use, the release layer is torn off, and the pasting layer can be pasted on the skin surface of the user.

7. The eye patch capable of eye tracking according to claim 6, characterized in that: The support layer is provided with an aluminum nose clip on a side away from the application layer; the aluminum nose clip is used to fix the eye patch body on the nose of the user.

8. The eye patch capable of eye tracking according to claim 6, characterized in that: The application layer is made of a gelatin-based material; the release layer is a single-layer silicon-sprayed release film.

9. The eye patch capable of eye tracking according to claim 1, characterized in that: The flexible integrated chip and the computer perform wireless transmission via Bluetooth.

10. A device capable of eye tracking, characterized in that: It comprises an eye patch capable of eye tracking as described in any one of claims 1-9.

Images