Device to prevent vision deterioration due to the use of display devices

Abstract

To provide a device for preventing the lowering of eyesight and asthenopia of a user by using a display device such as a portable terminal.SOLUTION: A device for preventing the lowering of eyesight of the present invention is provided in a display device having a front camera provided on a surface side on which a display screen is present. The device for preventing the lowering of eyesight includes: a congestion state measuring device that measures a congestion state of eyes of a user who views the display screen of the display device; an alert unit that issues a predetermined alert; and an alert instruction determination unit that compares the congestion state measured by the congestion state measuring device with an alert congestion state stored in advance and instructs the alert unit to issue an alert when it is determined that a predetermined condition is satisfied.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a device or method for preventing vision loss, eye fatigue, etc. by using a display device such as a personal computer, a mobile terminal such as a tablet or a smartphone.

[0002] Conventionally, it is known that the number of blinks decreases due to long-term use of a display device. When the number of blinks decreases, dry eye may occur, which may cause eye fatigue and vision loss. Therefore, there is a device that measures the presence or absence and the number of blinks of the user's eyes by the display device being used, and restricts the use of the display device in a predetermined case (Patent Document 1).

[0003] In addition, vision loss and the like caused by the use of a display device may occur not only due to blinks but also when the display device is used for a long time. Therefore, for example, there is a way to prevent eye fatigue and the like by looking at an object more than 20 feet away for 20 seconds after looking at the display screen for 20 minutes (20-20-20 rule).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, particularly in the case of a mobile terminal that holds a display image by hand, during use, the display device may be increasingly viewed close to the eyes, which may cause vision loss and eye fatigue.

[0006] Therefore, as a result of various studies, the inventor focused on the convergence of the eyes, grasped the state of the eyes from this convergence (convergence state), and aimed to prevent vision loss and the like. [Means for solving the problem]

[0008] The present invention provides a vision deterioration prevention device for a display device having a front camera provided on the side with the display screen, the vision deterioration prevention device comprising: a convergence state measuring device for measuring the convergence state of the eyes of a user viewing the display screen of the display device; an alert unit for issuing predetermined alerts; and an alert instruction determination unit for instructing the alert unit to issue an alert when it determines that predetermined conditions are met by comparing the convergence state measured by the convergence state measuring device with a pre-stored alert convergence state. The above-mentioned convergence state is the convergence angle of the user's eyes, and the convergence state measuring device comprises a pupil direction measuring device unit that measures the left and right pupil directions as seen from the display screen, and a convergence angle calculation device unit that calculates the angle between the pupil of the left eye and the pupil of the right eye as seen from the display screen based on the measured pupil directions, and the above-mentioned predetermined condition is characterized in that the calculated convergence angle is determined to be greater than or equal to a pre-stored alert convergence angle.

[0009] Also, The above alert convergence angle is characterized by being a value obtained by multiplying a predetermined reference convergence angle by a predetermined multiplier, or by adding a predetermined angle.

[0010] Also, The present invention provides a vision deterioration prevention device for a display device having a front camera provided on the side with the display screen, the vision deterioration prevention device comprising: a convergence state measuring device for measuring the convergence state of the eyes of a user viewing the display screen of the display device; an alert unit for issuing predetermined alerts; and an alert instruction determination unit for instructing the alert unit to issue an alert when it determines that predetermined conditions are met by comparing the convergence state measured by the convergence state measuring device with a pre-stored alert convergence state. The above-mentioned convergence state is the convergence angle of the user's eyes, and the convergence state measuring device comprises a screen distance measuring device unit that measures the screen distance between the display screen and the user's eyes, and a convergence angle calculation unit that calculates the convergence angle from the interpupillary distance of the user's left and right eyes and the screen distance measured by the screen distance measuring device unit, and the above-mentioned predetermined condition is characterized in that the calculated convergence angle is determined to be greater than or equal to a pre-stored alert convergence angle.

[0011] Also, The above alert convergence angle is characterized by being set according to the interpupillary distance. Furthermore, the above alert convergence angle is characterized by being a value obtained by adding a predetermined angle to a reference convergence angle calculated from a reference screen distance at which convergence is considered not to occur and the interpupillary distance at said reference screen distance. Furthermore, the above alert convergence angle is characterized by being a value obtained by multiplying a predetermined magnification or adding a predetermined angle to a reference convergence angle calculated from a predetermined reference screen distance at said reference screen distance and the interpupillary distance at said reference screen distance. Furthermore, the above alert convergence angle is a value obtained by multiplying a predetermined magnification or adding a predetermined angle to a reference convergence angle calculated from a predetermined reference screen distance at said reference screen distance and the interpupillary distance at said reference screen distance, and the predetermined reference screen distance is characterized by being the screen distance when the user extends their arm to its maximum extent and is furthest from the display screen, or the screen distance when the user starts using the device, or the furthest screen distance during use.

[0012] Furthermore, the alert convergence angle is characterized in that the alert convergence angle determination unit provided in the convergence state measuring device calculates a reference convergence angle from a preset screen separation and the interpupillary distance of the user at the screen distance, and the alert convergence angle is calculated from the calculated reference convergence angle.

[0013] Furthermore, the interpupillary distance is calculated by the image processing unit from the image captured by the front camera through image processing.

[0014] Furthermore, it is characterized by having a storage unit that stores the amount of time the user spends viewing the display screen (VDT time).

[0017] Also, The present invention provides a vision deterioration prevention device for a display device having a front camera provided on the side with the display screen, the vision deterioration prevention device comprising: a convergence state measuring device for measuring the convergence state of the eyes of a user viewing the display screen of the display device; an alert unit for issuing predetermined alerts; and an alert instruction determination unit for instructing the alert unit to issue an alert when it determines that predetermined conditions are met by comparing the convergence state measured by the convergence state measuring device with a pre-stored alert convergence state. The above-mentioned convergence state is the interpupillary distance of the user's left and right eyes, and the above-mentioned convergence state measuring device consists of an interpupillary distance measuring device that measures the interpupillary distance of the user. The above-mentioned predetermined condition is that the measured interpupillary distance is determined to be less than or equal to the pre-stored interpupillary distance.

[0018] Also, The above alert interpupillary distance is characterized by being a value obtained by multiplying a predetermined standard interpupillary distance by a predetermined reduction ratio, or by subtracting a predetermined distance from it.

Advantages of the Invention

[0020] According to the present invention, based on convergence, visual acuity decline, eye fatigue, etc. are judged, so that it becomes possible to prevent visual acuity decline and eye fatigue more effectively.

Brief Description of the Drawings

[0021] [Figure 1] It is an explanatory diagram of the display device of the visual acuity decline prevention device of the present invention. [Figure 2] It is an explanatory diagram of the visual acuity decline prevention device of the present invention. [Figure 3] It is an explanatory diagram of another embodiment of the visual acuity decline prevention device of the present invention. [Figure 4] It is an explanatory diagram of still another embodiment of the visual acuity decline prevention device of the present invention. [Figure 5] It is an explanatory diagram of still another embodiment of the visual acuity decline prevention device of the present invention.

Modes for Carrying Out the Invention

[0022] Hereinafter, the present invention will be described with reference to the drawings.

Examples

[0023] (1. Explanation of the overall configuration of the visual acuity decline prevention device)

[0024] As shown in Figures 1 and 2, the present invention relates to a vision deterioration prevention device 2 provided on a display device 1, such as a personal computer, tablet, or smartphone, which has a front camera 1b on the side with a display screen 1a. The vision deterioration prevention device 2 comprises a convergence state measuring device 3 that calculates the convergence state of the left and right eyes of a user looking at the display screen 1a of the display device 1, and an alert instruction judgment unit 4 that instructs an alert unit, such as the display screen 1a or speaker unit (not shown) of the display device 1, to issue an alert when it determines that predetermined conditions have been met, by comparing the convergence state calculated by the convergence state measuring device 3 with a pre-stored alert convergence state.

[0025] Reference numeral 5 denotes a calculation and storage unit that performs calculations and storage to enable the operation of various devices of the display device 1, such as the display screen 1a and the front camera.

[0026] Furthermore, the congestion state measuring device 3 and the alert instruction judgment unit 4 may be entirely or partially composed of, for example, computer programs (applications) and provided within the calculation memory unit 5. Alternatively, a device may be used in which all or part of these components are separately connected to the display device 1.

[0027] The convergence state described above includes, for example, the convergence angle (the angle between the left and right eyes as viewed from the display screen (this concept also includes the front camera; the same applies hereafter)).

[0028] Furthermore, the convergence state measuring device 3 includes a convergence angle calculation device, which comprises, for example, a pupil direction measuring device unit 3a that measures the left and right pupil directions as seen from the display screen, and a convergence angle calculation device unit 3b that calculates the angle between the pupils of the left eye and the right eye as seen from the display screen (calculated from the angle between them) based on the measured pupil directions, and the convergence angle is measured using this convergence angle calculation device.

[0029] Furthermore, the convergence angle measuring device described above may be configured in whole or in part by a computer program (app), for example, in addition to separately providing a commercially available device capable of measuring the convergence angle of the user. For example, there are no particular limitations as long as the app can calculate the convergence angles of the user's left and right eyes. For example, the user's left and right eyes may be captured by the front camera, the direction of the left and right pupils as seen from the front camera may be calculated from the captured images, and the angle between the left and right eyes as seen from the front camera from this calculated direction may be calculated and used as the convergence angle.

[0030] Alternatively, for example, the pupil direction measuring device 3a may be provided separately on the display device 1 using a commercially available angle measuring device, rather than as a computer program.

[0031] Furthermore, the convergence angle calculation device described above may also be configured to measure the convergence angle by measuring the direction of the left and right pupils, or, for example, as shown in Figure 3, to measure the screen distance between the display screen 1a and the user's eyes (midway between the left and right pupils), and to calculate the convergence angle (calculated from the screen distance) using a calculation formula described later, based on the interpupillary distance between the user's left and right eyes (distance between the centers of the black parts of the left and right eyes) and the screen distance measured by the screen distance measurement device 3c, and the convergence angle may be measured using this convergence angle calculation device.

[0032] In addition, the screen distance measuring device 3c may utilize a commercially available distance measuring device, such as one using laser light, installed in the display device, or it may utilize a commercially available computer program.

[0033] The above screen distance may be calculated, for example, by capturing images of the user's left and right eyes with the front camera, and then determining the distance from the captured images to the part of the face corresponding to the midpoint between the front camera and the left and right pupils, or the shortest distance between the front camera and the face.

[0034] Furthermore, the alert instruction determination unit 4 comprises a determination unit 4a that compares congestion conditions such as the congestion angle to determine whether or not the predetermined conditions are met, and an instruction unit 4b that, when the determination unit 4a determines that the predetermined conditions are met, instructs the alert unit to display an alert or the like.

[0035] Furthermore, the alert unit includes, in addition to the display screen and speaker unit (including the earphone unit), a light-up unit and a vibrating main unit provided on the display device 1. Examples of alerts include the display of characters or shapes on the display screen 1a, sounds, the illumination or flashing of lights, and vibration of the display device itself.

[0036] The above alerts also include cases where the screen is not displayed.

[0037] In addition to issuing alerts when predetermined conditions are met, the alert may also be issued intermittently at predetermined intervals, such as during rest periods, or at pre-set intervals, or again at the end of the predetermined period.

[0038] (2. Explanation of the calculation of the convergence angle)

[0039] Furthermore, when calculating the convergence angle from the interpupillary distance and screen distance as described above, the calculation formula is "Convergence angle △(prism) = 100 × interpupillary distance (cm) ÷ screen distance between the display screen and the eye (cm)" and the calculation formula is "1△(prism) = 0.57°", so the convergence angle (°) is calculated as "Convergence angle (°) = 100 × interpupillary distance (cm) ÷ screen distance between the display screen and the eye (cm) × 0.57°".

[0040] Furthermore, the interpupillary distance between the user's left and right eyes used when calculating the convergence angle may be a predetermined value, such as 6.5 cm for adults (the average interpupillary distance for adults) or 5 cm for children (the average interpupillary distance for children). However, other values ​​may also be used.

[0041] Furthermore, if the screen distance is, for example, 20 cm, the convergence angle can be calculated from the above formula as 18° for adults and 14° for children.

[0042] Furthermore, since a screen distance of 20 cm may lead to vision problems, the alert convergence angle should be set to, for example, 17° for adults and 13° for children, referring to the convergence angle values ​​mentioned above. However, the values ​​are not limited to these numbers. Also, the values ​​for adults and children may be the same.

[0043] In addition to using the average interpupillary distance of a typical person's eyes as a reference for the interpupillary distance of the user's left and right eyes, as shown in Figure 4, for example, the convergence state measuring device 3 may be equipped with an interpupillary distance calculation unit 3e, and the image processing unit of the interpupillary distance calculation unit 3e may use the image captured by the front camera to perform image processing on the image and determine the user's interpupillary distance.

[0044] One method for calculating the interpupillary distance using image processing in the image processing unit described above is to identify the pupil in the captured image through image processing, treat the pupil as a circle, and calculate the distance between the left and right pupils using the center of that circle as the pupil center. However, this method is not limited to this one, as long as the interpupillary distance can be measured.

[0045] Furthermore, the interpupillary distance may be measured in real time, and the convergence angle may be calculated in real time.

[0046] Alternatively, a predetermined value from the measured interpupillary distance may be set as the interpupillary distance, and the convergence angle may be calculated based on this set value.

[0047] For example, the value measured when the display device is first used, or a value measured before use, may be considered as the interpupillary distance, and the user may always use that value as the interpupillary distance when using the device. Alternatively, the interpupillary distance measured at the reference screen distance described later may be used.

[0048] (3. Explanation of specified conditions)

[0049] Furthermore, the above-mentioned predetermined conditions are determined from the relationship between the calculated congestion angle and the previously stored alert congestion angle, for example, that the calculated congestion angle is greater than or equal to the previously stored alert congestion angle.

[0050] The alert convergence angle mentioned above is pre-stored as a convergence angle that may result in decreased visual acuity, as described above. The alert convergence angle may also be stored according to the interpupillary distance.

[0051] In addition, as shown in Figure 5, for example, a separate alert convergence angle determination unit 6 may be used to determine a screen distance at which convergence is not considered to occur (but is not limited to cases where it does occur), such as a screen distance at which convergence is not considered to occur, or even if there is a possibility of convergence, a predetermined screen distance set in advance, for example, a screen distance of 30 cm or more, or the screen distance when the user extends their arm to its maximum extent and is furthest from the display screen, or the screen distance at which the user starts using the device, or the furthest screen distance during use. The system may then set a reference screen distance at this reference screen distance, a predetermined interpupillary distance, or a convergence angle calculated from the interpupillary distance measured by the interpupillary distance measurement unit, as the reference convergence angle. Based on this reference convergence angle, the system may set a value obtained by multiplying the reference convergence angle by a predetermined magnification (a magnification greater than 1), for example, 110%, as the alert convergence angle, or it may store an angle obtained by adding a predetermined angle (a positive angle), for example, +1°, to the reference convergence angle as the alert ventral angle.

[0052] Alternatively, the system may store the relationship between interpupillary distance and screen distance that can lead to decreased visual acuity, calculate the screen distance that can lead to decreased visual acuity based on the measured interpupillary distance of the user and the above relationship, and set and store the convergence angle at this screen distance as the alert convergence angle.

[0053] Furthermore, as an additional predetermined condition, for example, the alert instruction determination unit 4 may be further equipped with a timer unit (not shown) for measuring time, and the alert congestion angle may be set to a predetermined time, for example, 20 minutes or more.

[0054] The timer unit described above may also utilize the built-in timer unit provided in the arithmetic memory unit 5 of the display device 1.

[0055] Furthermore, the specified time mentioned above may be a continuous period of time or an accumulated period of time.

[0056] Furthermore, the alert congestion angle may be set to a different value depending on whether the desired time is taken into consideration or not.

[0057] Alternatively, the above alert congestion angle may be divided into several stages, and a predetermined time may be set for each stage of the alert congestion angle.

[0058] Alternatively, an alert may be issued if the sum of the product of the alert congestion angle at each stage and the time during which the alert congestion angle was at the corresponding stage exceeds a predetermined amount.

[0059] Furthermore, the above-mentioned vision deterioration prevention device may be equipped with a separate storage device (not shown), or the arithmetic memory device 5 of the display device 1 may be used to store the captured images being monitored, as well as the screen distance, interpupillary distance, number of alerts, VDT time (Visual Display Terminals), etc., and to output various information such as VDT time for a day or a week as needed.

[0060] Next, the method of using the present invention will be described.

[0061] As an initial setting for the above-mentioned vision deterioration prevention device, the device stores the alert convergence angle and, if necessary, the predetermined time for issuing an alert at that alert convergence angle.

[0062] Additionally, the user's interpupillary distance, which is necessary for calculating the convergence angle, is stored as needed. However, when calculating the user's interpupillary distance in real time, storing the interpupillary distance may be omitted.

[0063] Furthermore, the above-mentioned predetermined conditions are set.

[0064] Furthermore, users may be allowed to change the above initial values.

[0065] Then, when the user uses a mobile device or the like, the convergence angle is calculated, for example, by the convergence angle measuring device described above, either continuously or periodically.

[0066] Furthermore, when calculating the convergence angle using the screen distance and interpupillary distance, the screen distance measuring device measures the image distance continuously or periodically, and the convergence angle calculation unit 3b calculates the user's convergence angle continuously or periodically from the image distance and the interpupillary distance of the user stored in advance, or the interpupillary distance calculated by the interpupillary distance calculation unit.

[0067] Then, if the calculated convergence angle satisfies the predetermined conditions as determined by the determination unit 4a, the alert unit will, for example, display predetermined characters on the display screen, or the speaker unit will emit a sound.

[0068] Furthermore, for example, an alert could be set to be issued again after a predetermined rest period has elapsed.

[0069] Furthermore, the above-mentioned memory unit can store various information, such as VDT time, as needed, and make it possible to output it as needed.

[0070] According to the present invention, since vision loss and eye strain are judged based on convergence, it becomes possible to better prevent vision loss and eye strain. [Examples]

[0071] As an embodiment 2 of the present invention, the congestion state may be defined as, for example, the screen distance between the display screen and the user's eyes, and the congestion state measuring device may be defined as a screen distance measuring device unit that measures the screen distance, and an alert may be issued when it is determined that the measured image distance is less than or equal to a pre-stored alert screen distance.

[0072] Furthermore, an alert may be issued if the measured image distance is determined to be less than or equal to a pre-stored alert screen distance for a predetermined period of time or longer.

[0073] Note that the same parts as in Example 1 will have the same configuration.

[0074] Furthermore, the alert screen distance can be set to various values, such as 20cm or 10cm, which may cause congestion.

[0075] Additionally, the usage time may be adjusted according to the distance from the alert screen.

[0076] In this case as well, since vision loss and eye strain are being assessed, it becomes possible to better prevent vision loss and eye strain. [Examples]

[0077] As a third embodiment of the present invention, the convergence state may be, for example, the interpupillary distance between the left and right eyes of the user, and the convergence state measuring device may be configured as an interpupillary distance measuring device that measures the interpupillary distance of the user, and may issue an alert when it is determined that the measured interpupillary distance is less than or equal to a pre-stored interpupillary distance.

[0078] Furthermore, the system may be configured to issue an alert if the measured interpupillary distance is determined to be less than or equal to a pre-stored interpupillary distance for a predetermined period of time or longer.

[0079] Note that the same parts as in Example 1 will have the same configuration.

[0080] Furthermore, as an alert interpupillary distance, in addition to pre-memorizing interpupillary distances that may cause vision loss, the interpupillary distance of the user may be measured at a screen distance where convergence is not thought to have an effect, for example, with the screen distance relatively far away, and this may be used as the reference interpupillary distance. Based on this reference interpupillary distance, for example, a value obtained by a predetermined reduction ratio (e.g., 90%) may be used as the alert interpupillary distance, or a value obtained by subtracting a predetermined distance (e.g., 0.5 cm) may be used as the alert interpupillary distance.

[0081] In this case as well, since vision loss and eye strain are being assessed, it becomes possible to better prevent vision loss and eye strain. [Explanation of symbols]

[0082] 1 Display device 1a Display screen 1b Front camera 2 Visual deterioration prevention device 3. Congestion State Measurement Device 3a Pupil direction measuring device section 3b Vergence angle calculation unit 3c Screen distance measuring device section 3D Convergence Angle Calculation Unit 3e Pupillary distance calculation section 4. Alert Instruction Decision Unit 4a Judgment part 4b Instruction section 5 Arithmetic storage section 6. Alert Congestion Angle Determination Unit

Claims

[Claim 1] A device for preventing vision loss, provided for a display device having a front camera located on the side with the display screen, The vision deterioration prevention device includes a convergence state measuring device that measures the convergence state of the user's eyes when viewing the display screen of the above-mentioned display device, An alert unit that issues a predetermined alert, The system consists of an alert instruction determination unit that compares the congestion state measured by the above-mentioned congestion state measuring device with a pre-stored alert congestion state, and instructs the alert unit to issue an alert if it determines that predetermined conditions are met. The above convergence state is the convergence angle of the user's eyes. The above-mentioned convergence state measuring device comprises a screen distance measuring device unit that measures the screen distance between the display screen and the user's eyes, and a convergence angle calculation unit that calculates the convergence angle from the interpupillary distance between the user's left and right eyes and the screen distance measured by the screen distance measuring device unit. The above predetermined condition is when the calculated congestion angle is determined to be greater than or equal to a pre-stored alert congestion angle. The above alert convergence angle is a value obtained by multiplying a predetermined magnification by a predetermined factor, or by adding a predetermined angle, the reference convergence angle calculated from a predetermined reference screen distance and the interpupillary distance at said reference screen distance. The device for preventing vision deterioration is characterized in that the predetermined reference screen distance is the screen distance when the user extends their arm to its maximum extent and is furthest from the display screen, or the screen distance when the user starts using the device, or the furthest screen distance during use.

Images