JP7188749B2 - Underwater goggle frequency determination method and underwater goggle supply system - Google Patents

Description

The present invention provides a method for determining the lens power of underwater goggles worn to cover the user's eyes during swimming, diving, etc., and provides underwater goggles with the lens power determined according to the method. about the system to do.

As described in Japanese Patent Application Laid-Open No. 4-332571 (Patent Document 1 below), a prescription lens having an arbitrary power is liquid-tightly fitted and fixed inside a lens cylinder having a flat outer surface (front surface, front surface). In addition, underwater goggles are known that allow even a nearsighted person to see well underwater.

JP-A-4-332571

In the underwater goggles, since the outer surface of the lens barrel is flat (radius of curvature ≈∞), the water in contact with the outer surface is also flat, and the refractive index n ₁ =1.33, which is different from that of air (refractive index=1.0). The refractive power in water and the refractive power in air do not differ, and the same refractive correction effect can be given when worn in air and when worn in water. This is true whether the goggles are intended for refractive correction or not.
Here, equation (1) for the refractive power (lens surface) D is shown below. In equation ( ₁ ), n1 is the refractive index of the object _- side medium, n2 is the refractive index of the lens, _R1 is the radius of curvature of the lens surface, and f is the focal length.

However, even if the outer surface of the lens barrel is flat, the appearance of an object at a finite distance in front of the eye differs between underwater and air. Because the refractive index of water is greater than the refractive index of air, objects in water appear closer than in air with an apparent distance of 1.0/1.33, and are actually at the same distance as in air. Some objects require more accommodation.
However, Japanese Patent Application Laid-Open No. 4-332571 makes no mention of such adjusting power, and only mentions that an arbitrary degree is selected. That is, Japanese Patent Application Laid-Open No. 4-332571 does not disclose any criteria for selecting a dioptric power in consideration of visibility in water.
Especially in recent years, the number of middle-aged and older swimmers and divers has been increasing, and due to the decline in eye accommodation due to aging, there is a situation where an object that is visible in the air cannot be seen at the same distance underwater. becoming more likely to occur.
SUMMARY OF THE INVENTION It is therefore a primary object of the present invention to provide a method for determining the power of underwater goggles with consideration for visibility in water, and a system for supplying the power of underwater goggles with consideration for visibility in water. to do.

In order to achieve the above object, the invention described in claim 1 is a method for determining the power of underwater goggles, wherein the power in the air and the distance |a| The power of the goggles is added to the power in air by adding _a correction amount calculated by Equation (8) (na is the refractive index of air and _nw is the refractive index of water) related to the distance |a| It is characterized by being determined by
According to a second aspect of the invention, in the above invention, the power of the underwater goggles includes a distance power and an addition power related to progressive multifocal, and the distance power or the addition power is determined by the correction amount. It is characterized by being
In order to achieve the above object, the invention according to claim 3 is a system for supplying underwater goggles, comprising: means for receiving a frequency in air and a distance |a| The power of the underwater goggles is determined by adding the correction amount calculated by the following formula (8) (na is the refractive index of air and _nw is the refractive index of water) related to the distance | _a | and means for selecting or forming the underwater goggles or lenses of the underwater goggles for the determined power.
According to a fourth aspect of the invention, in the above invention, the power of the underwater goggles includes a distance power and an addition power related to progressive multifocal, and the distance power or the addition power is determined by the correction amount. It is characterized by being

The main advantage of the present invention is to provide a method by which the visibility-friendly underwater goggle power is determined, and a system by which the underwater visibility-friendly power is supplied. That's what it is.

It is a schematic diagram concerning the imaging formula of a lens. 1 is a block diagram of an underwater goggle delivery system and related equipment according to the present invention; FIG. 4 is a flowchart of an operation example (an example of an underwater goggle supply method) of the underwater goggle supply system according to the present invention;

Hereinafter, examples of embodiments according to the present invention will be described. The present invention is not limited to the following forms.

Underwater goggles according to the present invention include translucent lenses.
Two lenses may be used so as to correspond to the left and right eyes, respectively (underwater goggles), or one lens may be used to commonly cover the left and right eyes (diving mask). In the former case, each lens has a surface for power correction, and in the latter case, a lens portion having a surface for power correction is provided in a portion positioned in front of each eye when worn.
The lens is made of a translucent material such as glass, preferably plastic.
In the case of swimming goggles, each lens is placed in a corresponding opening in a goggle frame with openings on the left and right sides, and in the case of diving masks, the lenses have openings sized to encompass about one-third of the face. It is put into an opening in the goggle frame. In either case, a goggle body is formed by the lens and the goggle frame, and headbands are provided so as to connect the left and right ends of the goggle body. The user wears the goggles main body and the headband by wrapping them around the head, with the lenses in front of the eyes, the ends of the headband above the ears, and the headband crossing the back of the head.
The lens may be a single plate, or may be a combination of a plurality of members such as a front lens body and a rear lens body joined together. The front or rear lens body may be a flat plate that does not involve power correction, or may be integral with the goggle frame and receive the rear or front lens body.

The power of the lens is given by making at least one of the front surface (surface on the object side) and the rear surface (surface on the eye side) of the lens a predetermined curved surface, preferably refractive power in water and refractive power in air The front surface is flattened and the shape of the rear surface is adjusted so as not to differ from the .
As shown in the following [Table 1], the power of the lens is 1.0/1.33 when an object in water appears closer than in the air, which is more than an object in the air at the same distance. is determined in consideration of the need for the adjustment power of "D" in [Table 1] is a unit of frequency (diopter).

The amount of power correction required to see an object at a finite distance in front of the eye with the same accommodative power in water and in air is calculated by the lens imaging formula given by the following equation (2).
FIG. 1 shows a schematic diagram relating to the imaging formula of the lens. In the imaging formula of the lens, n is the object-side refractive index (1 for air, 1.33 for water), n' is the image-side refractive index, a is the object point distance, that is, the distance from the lens L to the object point O (m , positive to the right and negative to the left), b is the image point distance, that is, the distance from the lens L to the image point P (m, positive to the right and negative to the left), and D is the power of the lens. is.
In the case of underwater goggles, since the image side, ie, the eye side, is air, n'=1, and further modifying the equation (2) yields the following equation (3). In equation (3), b is the image point distance, which corresponds to the object point distance after passing through the lens. The reciprocal of b, 1/b, is the accommodation power (D) required to see the object through the lens.

In the following, the case of viewing an object at a certain finite distance a with the same accommodation power in air and in water will be described.
First, in air, the accommodation force represented by the following equation (4) is required, where n=1 in equation (3). where _D1 is the lens power associated with the accommodation power required in air.

The following equation (5) is obtained by applying 1/b, which is the left side of equation (4), to the n'/b part in equation (2), which is the imaging formula of the lens. Here, _D2 is the lens power for viewing an object at a predetermined finite distance a with the same accommodative power in air and in water.

When 1.33, which is the refractive index of water, is substituted for n in Equation (5) and further rearranged, Equation (6) below is obtained.

D ₂ -D ₁ corresponds to the power correction amount required to see an object at a finite distance a in air and in water with the same accommodation power, which is -0.33/a and depends on the distance a from the lens to the object. Since −0.33 in equation (6) is the refractive index of air n _a (=1) minus the refractive index of water n _w (=1.33) (n _a −n _w ), the equation (6) can also be expressed as the following equation (7).
Furthermore, in equations (6) and (7), the finite distance a becomes a negative number on the object side, which is different from the usual concept of "distance" in other fields. If the value |a| (distance |a|) is used, the sign of (n _a −n _w ) also changes and becomes −(n _a −n _w )=n _w −n _a , so the following equation (8 ) can also be written as

Therefore, by setting a specific finite distance a at which the user mainly wants to see well in water as well as in air, it follows from equations (6) and (7) that A correction amount of the power of the underwater goggles with respect to the power of the spectacles (ordinary spectacles) is calculated. Since the finite distance a is the distance on the object side of the lens L, it is a negative number obtained by adding a minus sign to the actual distance value in the equations (6) and (7). Note that the calculated correction amount may be finely adjusted according to at least one of the user's actual vision and ease of handling (such as the lens being stocked every 0.50D).
For example, when the user attaches great importance to the visibility at a distance of 2 m (meters) ahead in diving or swimming, the specific finite distance a is 2 m on the object side of the lens L, so a=-2. is set as a negative number, and the power shifted by +0.165D (diopter) from the normal power is determined as the power of the underwater goggles from equations (6) and (7). This is the same as the shift amount (correction amount) calculated by setting |a|=2 in Equation (8).
Alternatively, if the visibility of 1 m (meter) ahead is important, a = -1 is set, and the power shifted by +0.33D from the normal power from equations (6) and (7) is the underwater goggles. is determined as the frequency of This is the same as the shift amount (correction amount) calculated by setting |a|=1 in Equation (8).
In addition, when the visibility of 50 cm (centimeter) ahead is important due to the desire to see fish swimming nearby during diving, a = -0.5 is set, and from the equations (6) and (7), normal The power shifted by +0.66D from the power of is determined as the power of the underwater goggles. This is the same as the shift amount (correction amount) calculated by setting |a|=0.5 in Equation (8).

Further, the normal eyeglass power may be the power related to the progressive multifocal lens, and the correction amount of the underwater goggles power for the normal eyeglass power may be related to the progressive multifocal lens.
Alternatively, when normal eyeglasses are single-focal powers and underwater goggles are progressive multifocal powers, progressive The power of multifocal underwater goggles may be determined.
The power of underwater goggles related to progressive multifocal may include distance power and addition power, the correction amount is applied to the distance power, and the near power is added to the distance power after applying the correction amount. It may be added, or it may be applied to the addition power while maintaining the distance power at the normal power.

Thus, in the method of determining the power of the underwater goggles, the power in the air (normal power) and the distance a to be viewed mainly in the water are specified, and the power of the underwater goggles is compared to the power in the air, It is determined by adding the correction amount calculated by Equation (8) (na is the refractive index of air and _nw is the refractive index of water) for the distance | _a |. Therefore, it is possible to determine the degree that can visually recognize an underwater object at a distance |a| that you want to see mainly with the same adjustment power as the normal power, and the visibility in the water is considered. A method is provided in which the power of underwater goggles is determined.
Further, the power of the underwater goggles includes the distance power and the addition power related to the progressive multifocal, and at least one of the distance power and the addition power is determined by the correction amount. Thus, a method is provided for determining the power of underwater goggles that provide excellent visibility in the water both near and far.

A system for supplying underwater goggles having lens powers determined according to such a method for determining the power of underwater goggles will be described below.
FIG. 2 is a block diagram of the underwater goggle supply system 1 and related equipment.
The underwater goggle supply system 1 is a server computer, and includes display means 2 , input means 4 , storage means 6 , communication means 7 and control means 8 .
The underwater goggle supply system 1 is installed, for example, in a lens manufacturer, a laboratory (warehouse) stocked with various lenses, or a store.

The display means 2 displays various information, and is, for example, a liquid crystal display or an organic electroluminescence display.
The input means 4 receives input of various kinds of information, and is at least one of a keyboard and a pointing device, for example.
The display means 2 and the input means 4 may be integrated like a touch panel.

The storage means 6 stores various information, and is at least one of a hard disk, a memory, and a disk drive, for example.
The communication means 7 communicates various information with an external device, and here communicates with the Internet IN.
The control means 8 controls these means, and is, for example, a central processing unit (CPU). The control means 8 sequentially reads out the underwater goggle supply program stored in the storage means 6, and performs processing related to the supply of the underwater goggles according to the program.

The communication means 7 of the underwater goggle supply system 1 is communicably connected to one or more terminals T via the Internet IN. Incidentally, the communication means 7 and 17 may communicate via other networks such as dedicated lines. Also, the communication means 7 and 17 may be connected by a local area network. Furthermore, communication between the communication means 7, 17 may be wireless and/or wired.
The terminal T is a computer and, like the underwater goggle supply system 1, has a display means 12, an input means 14, a storage means 16, a communication means 17, and a control means .
The terminal T is installed on the user side, for example, in the same store as or different from the store where the underwater goggle supply system 1 is installed, or in the user's home (personal computer, etc.) or at hand (tablet, smart device, etc.). .

FIG. 3 is a flowchart relating to an operation example of the underwater goggle supply system 1 (an example of an underwater goggle supply method).
The control means 18 of the terminal T executes the underwater goggle ordering program stored in the storage means 16 (based on the user's input to start the program), and displays on the display means 12 the desired to see well with the underwater goggles (highest visibility is emphasized). ) display an input section prompting for input of the distance |a| The normal power may be at least one of distance power and add power for progressive multifocal. Also, instead of inputting the distance |a|, a distance a, which is a negative number on the object side, may be input.
When the distance |a| and the normal frequency are input, the control means 18 stores the distance |a| It is transmitted to the underwater goggle supply system 1 via the means 17 and the Internet IN.

When the control means 8 of the underwater goggle supply system 1 receives the terminal ID-attached distance |a| By substituting a| into the equation (8), the correction amount of the power of the underwater goggles is calculated and stored in the storage means 6 (step S3). Equation (8) is stored in the storage means 6 as a component of the underwater goggle supply program. At least one of formulas (6) and (7) may be used.

Further, the control means 8 determines the power related to the lenses of the underwater goggles by applying the correction amount of the power of the underwater goggles to the normal power, and stores it in the storage means 6 (step S4). Selection of goggles is performed by at least a command to a warehouse system (a system that automatically transports a predetermined stocked item to a predetermined location or guides the storage location of the stocked item) and a command to the worker by displaying on the display means 2. One side etc. is made to perform (step S5). The power correction amount may be applied to at least one of the distance power and the addition power related to the progressive multifocal.
Incidentally, the control means 8 may instruct the machine for manufacturing the underwater goggles or the lenses thereof to form the underwater goggles or the lenses thereof according to the dioptric power. If the lenses are formed, they may be fitted to the underwater goggle body in situ or at the user's side or at points therebetween.

The control means 8 instructs the shipping of the underwater goggles thus selected (formed) in order to supply them directly to the user through a shop or by a carrier (step S6).
The command to ship is performed by at least one of a command to the shipping system and a command to the operator by display on the display means 2, like the command to select (form) the underwater goggles.
The destination can be identified by the terminal ID.
When the underwater goggle supply system 1 and the terminal T are installed in the same store, the selected (formed) underwater goggles may be handed over to the user by the store clerk. Further, in this case, the underwater goggle supply system 1 and the terminal T may be configured by one computer.
Further, the fact that the underwater goggles have been shipped may be displayed on the display means 12 of the terminal T in response to a command from the control means 8 to the terminal T via the communication means 7 and the Internet IN.

In this way, the user can be supplied with underwater goggles having a degree of good visibility at a desired distance |a| by the underwater goggle supply system 1 .

That is, the underwater goggle supply system 1 includes means (input means 4, communication means 7) for receiving power in air and distance |a| (8) (na is the refractive index of air, _nw is the refractive index of water) for determining the power of the underwater goggles by adding _a correction amount (control means 8) for determining and means for selecting or configuring underwater goggles for said power. Thus, there is provided a system in which underwater goggles are supplied with a power that takes into consideration visibility in the water.
Further, the power of the underwater goggles includes the distance power and the addition power related to the progressive multifocal, and at least one of the distance power and the addition power is determined by the correction amount. Therefore, there is provided an underwater goggle supply system that has a power that is excellent in underwater visibility both in the near and far distances.

Next, Examples 1 and 2 of the present invention will be described. Examples 1 and 2 relate to a method for determining power of underwater goggles.
In addition, the present invention is not limited to the following examples. Also, depending on how the present invention is perceived, the example may become a comparative example that does not belong to the present invention.

[Example 1]
Example 1 relates to a case where the user U1 designates 50 cm as the distance |a| that he wants to see frequently during diving and orders a diving mask.
User U1's normal refractive power is S power -4.00D (R: S-4.00) in the right eye and similarly L: S-4.00 in the left eye.
In order to see an object 50 cm ahead with the same accommodation power as in the air, a = -0.5 in equation (6) or |a| = 0.5 in equation (8) gives 0.33/0 A correction of .50 = +0.66D needs to be added. Then, from the viewpoint of ease of handling, the shift amount (correction amount) was finely adjusted from +0.66D to +0.50. .50.
In this case, theoretically, there is -0.43D myopic uncorrected for distance vision in air. For example, a correction of 0.33/5=+0.066D is enough to see an object 5m ahead, but a correction of +0.66D is added.
However, in reality, when viewed from a distance in water, it is seen much closer than in the air.
The visual acuity of the user U1 was measured while the user U1 wore underwater goggles (diving mask) of R: S-3.50, L: S-3.50, and the actual visual acuity was about 1.0. Therefore, the determination of R: S-3.50, L: S-3.50 (prescription power for user U1) was also good for distance vision. In addition to the visual acuity measurement, it was confirmed that the visibility of an object 50 cm ahead of the user U1 was extremely good.

[Example 2]
Example 2 relates to a case where the user U2 designates 33 cm as the distance |a| that he wants to see frequently during diving and orders a diving mask.
User U2's normal refractive powers are R: S-4.00 and L: S-4.00. Also, the residual accommodation power is 3.00D, which is enough to see an object 33 cm in front of the eyes in the air.
In order for the user U2 to see an object 33 cm in front of his/her eyes underwater, an accommodative power of 3.00+0.33/0.33=4.00D is required, and the normal dioptric power can only be seen in a blurred state.
Therefore, in the diving mask, a = -0.5 in equation (6) or |a| It is conceivable to shift to R: S-3.00 and L: S-3.00.
However, with such a power, myopia is uncorrected in distant vision. For example, in visual recognition of an object 5 m away, correction of 0.33/5 = +0.066 is sufficient, so myopia is uncorrected by -0.93D. .
Therefore, a progressive multifocal lens is selected as the diving mask lens, and the power of the progressive multifocal lens is 1.00D for the distance power R: -4.00 and L: -4.00. The near power is -3.00D, which makes it easier to see objects 33 cm in front of the eye, and the distance power is -4.00D, which provides good visibility in the distance. and to be supplied for the designated dives.
By wearing a diving mask with such power, the user U2 can see both far and near underwater with the same adjustment power as in the air.

DESCRIPTION OF SYMBOLS 1.. Underwater goggle supply system, 4.. Input means, 7.. Communication means, 8.. Control means, L.. Lens.

Claims (4)

A method for determining the power of underwater goggles, comprising:
The frequency in the air and the distance |a| that you want to see mainly in the water are specified,
A method for determining power of underwater goggles, wherein the power of underwater goggles is determined by adding a correction amount calculated by the following formula (A) regarding said distance |a| to said power in air.

where _na is the refractive index of air and _nw is the refractive index of water. The power of underwater goggles includes distance power and addition power related to progressive multifocal,
2. The method of determining the power of underwater goggles according to claim 1, wherein the distance power or the addition power is determined by the correction amount. A system for supplying underwater goggles, comprising:
means for receiving power in air and distance |a|
By adding a correction amount calculated by the following formula ( _A ) (na is the refractive index of air, _nw is the refractive index of water) related to the distance |a| to the power in air, the power of the underwater goggles a means for determining

means for selecting or forming underwater goggles or lenses for underwater goggles according to the determined power;
An underwater goggle supply system comprising: The power of underwater goggles includes distance power and addition power related to progressive multifocal,
4. The underwater goggle supply system according to claim 3, wherein the distance power or the addition power is determined by the correction amount.

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