Laser light irradiation device and eyeglass lens positioning device using the same

Abstract

To provide a laser beam irradiation device which is used to correct the difference in scale between an image on a display of a mobile terminal and an image formed on the basis of the inner edge contour data of an eyeglass frame having been acquired by a frame tracer, and an eyeglass lens positioning device using this laser beam irradiation device.SOLUTION: Provided is a laser beam irradiation device for irradiating the face of a subject with a laser beam, which is used to measure the scale of an image displayed on a display to the actual stuff. The laser beam irradiation device comprises: at least two laser resonators for causing at least two bright points to appear on the face of the subject by laser beams; support means for supporting the laser resonators; and attachment means for attaching the support means to the mobile terminal such that the distance between the camera lens of the mobile terminal and the subject and the distance between the laser resonators and the subject are equal.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a laser light irradiation device and a spectacle lens positioning device using the same. More specifically, the present invention relates to a laser light irradiation device used for aligning the pupil center position and the optical center position of a lens during spectacle manufacturing and for processing and adjusting spectacle lenses, and a spectacle lens positioning device using the same.

Background Art

[0002] When positioning a spectacle lens as described above, for example, as shown in WO2020249643, the face of a subject wearing a spectacle frame without a spectacle lens is photographed by a camera of a mobile terminal (tablet terminal), and the image is displayed on a display. Conventionally, a pupil center position discrimination / measurement device that discriminates and measures the pupil center position of the subject with respect to the inner edge contour of the rim of the spectacle frame has been used.

[0003] When using a mobile terminal as described above, the discrimination / measurement can be performed easily. However, depending on the type of spectacle frame or the shooting state, there is a problem that it may be difficult to obtain accurate data because the image of the spectacle frame is unclear or distorted.

[0004] To solve such a problem, it is conceivable to form a virtual image of the rim using the data of the inner edge contour of the rim of the spectacle frame obtained by a conventionally used frame tracer, and to correct the image on the display of the mobile terminal using this virtual image. However, the data of the inner edge contour of the rim of the spectacle frame obtained by the frame tracer is the data of the original size of the spectacle frame, while the image of the spectacle frame on the display is a scaled image according to the distance between the camera and the subject. Therefore, the image formed based on the data of the inner edge contour of the rim of the spectacle frame obtained by the frame tracer cannot be used as it is. [Prior art documents] [Patent Documents]

[0005] [Patent Document 1] WO2020249643 publication [Overview of the project] [Problems that the invention aims to solve]

[0006] Therefore, the present invention aims to provide a laser light irradiation device used to correct the difference in scaling ratio between an image on the display of a mobile terminal and an image formed based on data of the inner edge contour of the rim of an eyeglass frame acquired by a frame tracer, and an eyeglass lens positioning device using the laser light irradiation device. [Means for solving the problem]

[0007] The above issues are as follows (1)~( 7 This is achieved by a laser beam irradiation device and an eyeglass lens positioning device configured as follows. (1) The subject's face, wearing eyeglass frames without lenses, is photographed by a camera and displayed as an image on a screen. It is a tablet PC. A laser light irradiation device used in conjunction with a pupil center position determination and measurement device that uses a mobile terminal to determine and measure the pupil center position of the subject relative to the inner edge contour of the rim of an eyeglass frame, for irradiating the face of the subject with laser light used to measure the scale ratio of an image displayed on the display relative to the actual object, wherein the laser light irradiates the face of the subject 4 points To make the bright spots appear 4 laser oscillator Casing equipped , and the distance between the camera lens of the mobile terminal and the subject and the distance between the laser oscillator and the subject are the same, Casing For attaching to the aforementioned mobile terminal Mounting adapter It is equipped with, The four laser oscillators consist of a central first laser oscillator that emits a first laser beam representing a first bright spot on the subject's face, second and third laser oscillators positioned one on each side of a horizontal line including the central laser oscillator, which emit second and third laser beams representing a second and third bright spot on the subject's face, and a fourth laser oscillator positioned directly below the first laser oscillator in a vertical direction, which emits a fourth laser beam diagonally downward to represent a fourth bright spot on the subject's face. The aforementioned mounting adapter attaches the casing to the mobile terminal by clamping the frame portion of the mobile terminal between the upper and lower adapter members. The upper adapter member and the lower adapter member have a variable distance between them due to an expandable / contractible member, thereby allowing them to accommodate the size of the mobile device, and further The mounting adapter has an upper adapter member and a lower adapter member, and the distance between them is variable by an expandable / contractable member. This allows for adjustment of the lateral position of the casing. This adjustment function allows the mounting adapter to be positioned so that the optical axes of the first and fourth laser beams emitted by the first and fourth laser oscillators lie on a vertical line that includes the optical axis of the camera lens of the mobile terminal. A laser light irradiation device characterized by the following features. (2) The interval between the first laser oscillator and the second laser oscillator, and the interval between the first laser oscillator and the third laser oscillator are equal. A laser beam irradiation device. (3) The aforementioned The distance between the two laser oscillators is 10 mm to 100 mm. 2 A laser light irradiation device. (4) The aforementioned The distance between the two laser oscillators is 50 mm. 2 A laser light irradiation device. (5) When the laser light irradiation device is located at a predetermined distance from the subject, the fourth laser oscillator is positioned at an angle such that the distance between the fourth bright spot and the first bright spot is equal to the distance between the second, third, and first bright spots. 4th The above ( is configured to emit laser light) 1 A laser light irradiation device. (6) The aforementioned each The laser light emitted from the laser oscillator is of Class 1 according to JIS C 6802:2014 and is visible light that meets safety standards. 1 A laser light irradiation device. (7) The aforementioned each The oscillation wavelength of the laser oscillator is in the 635 nm band. 1 A laser light irradiation device. [Effects of the Invention]

[0008] According to the laser light irradiation device of the present invention and the spectacle lens positioning device using the laser light irradiation device, it has high portability, does not require auxiliary instruments for measurement, is easy to operate and has high portability, can precisely position the spectacle lens with respect to the spectacle frame, and has the effect of improving the accuracy of lens positioning and processing adjustment during spectacle production. Therefore, when wearing a spectacle frame in which a spectacle lens produced using the laser light irradiation device of the present invention and the spectacle lens positioning device using the laser light irradiation device is fitted, the optical center of the spectacle lens coincides with the pupil center of the wearer, and the wearer can obtain a good visual field. Furthermore, since non-contact measurement is performed on the subject, it is also effective in reducing the measurement load on the subject.

Brief Description of Drawings

[0009] [Figure 1] Explanatory drawing for explaining the outline of the spectacle lens positioning device of the present invention. [Figure 2] Front view of the mobile terminal. [Figure 3] Front view showing the state where the laser light irradiation device is attached to the mobile terminal. [Figure 4] Side view of the laser light irradiation device in FIG. 3. [Figure 5] Explanatory drawing showing the face of the subject irradiated with four laser lights by the laser light irradiation device. [Figure 6] Explanatory drawing for explaining the laser light irradiated by the laser light irradiation device, (a) is a plan view, and (b) is a side view. [Figure 7] Block diagram for explaining the configuration of the processing circuit of the mobile terminal. [Figure 8] Flowchart for explaining the procedure of positioning to the pupil center position of the boxing center using the spectacle lens positioning device of the present invention. [Figure 9] Explanatory drawing for explaining the deviation amount between the boxing center position and the pupil center position in the image on the display. Embodiment of the Invention

[0010] The following describes a laser light irradiation device according to an embodiment of the present invention and a spectacle lens positioning device using the laser light irradiation device, with reference to the attached drawings. In this invention, the boxing center position of the rim of the spectacle frame coincides with the optical center position of the spectacle lens. As shown in Figure 1, the spectacle lens positioning device 1 comprises a mobile terminal 10 (which may be a tablet, for example), a laser light irradiation device 40, and a frame tracer 50. As shown in Figure 1, the mobile terminal 10 and the frame tracer 50 are connected to a control PC 100 via LAN (wired, wireless, etc.) and their operation is controlled. The control PC 100 also primarily transfers data from the frame tracer 50 to the mobile terminal 10. The control PC 100 is also connected to a control device 110 (Figure 1) for a lens processing machine via the Internet, VPN (Virtual Private Network), or other communication lines. The processing machine is used by a business that provides entire spectacles or lenses. The control device is used by the business or a third party closely related to the business.

[0011] Mobile device 10 Next, with reference to Figure 2 and other figures, the mobile terminal 10 used in this spectacle lens positioning device will be described. In this specification, a mobile terminal refers to a device that uses a camera to photograph the face of a subject wearing spectacle frames without spectacle lenses and displays the image on a display, and includes a camera, display, memory, and processing circuitry for running various applications (shown as reference numeral 20 in Figure 6), such as a tablet, tablet PC, mobile PC, or smartphone. Each component and part may be built-in or external, but for simplicity, built-in types are preferred. The above-mentioned "spectacle frames without spectacle lenses" also includes cases where dummy (temporary) lenses, such as lenses without prescription, are installed.

[0012] As shown in Figure 2, the mobile terminal 10 includes a camera 12 for taking pictures, and a display 16 surrounded by a frame 14, which consists of a large number of pixels arranged vertically and horizontally to represent the subject captured by the camera 12 as an image I. To obtain more detailed data from mobile devices, a high resolution is desirable, and currently, a resolution of 3840 x 2160 pixels has been announced.

[0013] Laser light irradiation device 40 Next, with reference to Figure 3 and subsequent figures, a laser light irradiation device 40 according to an embodiment of the present invention will be described. As described in the section on the mobile terminal 10, the laser light irradiation device 40 irradiates the face of a subject wearing eyeglass frames without lenses with the camera 12 of the mobile terminal 10 when displaying the image I on the display 14, thereby representing bright spots Aa, Ab, Ac, and Ad as shown in Figure 5. As a result, bright spot images 12a, 12b, 12c, and 12d caused by the laser light are displayed on the image I.

[0014] To achieve the above, the irradiation device body 41 is equipped with a casing 42, which contains four laser oscillators. These four laser oscillators consist of a central first laser oscillator 43 that irradiates the subject's face with a first laser beam L1 (see figure; the same applies hereinafter) and represents the first bright spot Aa (center of the forehead), second and third laser oscillators 44 and 45, one on each side of a horizontal line including the central first laser oscillator 43, that irradiate the subject's face with second and third laser beams L2 and L3, respectively and represent the second bright spot Ab and third bright spot Ac (both sides of the forehead), and a fourth laser oscillator 46 positioned directly below the first laser oscillator 36 that irradiates the subject's face with a fourth laser beam L4 and represents the fourth bright spot Ad, located vertically below the first bright spot Aa (on the bridge of the nose).

[0015] The first interval between the first laser oscillator 43 and the second laser oscillator 44, and the second interval between the first laser oscillator 43 and the third laser oscillator 45 may be different values, but it is preferable that they be equal intervals. The first and second intervals are preferably 10 mm to 100 mm, and particularly preferably 50 mm, considering the width of a human forehead. In the following descriptions in this specification, this interval will be assumed to be 50 mm.

[0016] The fourth laser oscillator 46 is positioned diagonally downward so that it emits laser light diagonally downward and can display a fourth bright spot Ad vertically below the first bright spot Aa on the subject's face. For example, when the distance between the fourth laser oscillator and the subject is 50 cm, the distance between the first bright spot and the second and third bright spots (50 mm) is set to be equal to the third distance, which is the distance between the first and fourth bright spots. This third distance is 50 mm. For this reason, the fourth laser oscillator emits the fourth laser light L4 at an angle of approximately 5.7° downward with respect to the first laser light L1. The operation and function of this fourth laser light L4 will be explained later.

[0017] The laser light emitted from the four laser oscillators is of Class 1 according to JIS C 6802:2014 and is visible light that meets safety standards. Specifically, the oscillation wavelength of the laser oscillators is preferably in the 635 nm range.

[0018] The laser light irradiation device 40 includes an attachment adapter 50 for attaching the irradiation device body 41 to the mobile terminal 10, as shown in Figure 3. The mounting adapter 50 attaches the laser beam irradiation device 40 to the mobile terminal 10 by clamping the frame portion 14 of the mobile terminal 10 between the upper adapter member 52 and the lower adapter 54 at its upper and lower edges. The distance between the upper adapter member 52 and the lower adapter 54 is adjustable by an expandable member 56, thereby accommodating the size of the mobile terminal 10.

[0019] Furthermore, since this mounting adapter 50 is of the type that clamps the mobile terminal 10 from above and below, the lateral position of the laser beam irradiation device 40 can be adjusted. This adjustment function allows the device to be positioned so that the optical axes of the first and fourth laser beams L1 and L4 emitted by the first and fourth laser oscillators lie on a vertical line that includes the optical axis of the lens of the camera 12 of the mobile terminal 10.

[0020] Frame Tracer 60 The frame tracer used in the spectacle lens positioning device according to the embodiment of the present invention may have any structure, but for example, the frame tracer provided by HOYA Corporation (product number: GT5000) can be used.

[0021] Using the frame tracer described above, the frame shape data is obtained, for example, as follows, in order to process the lenses that will be fitted into the frame.

[0022] (1) The measurer uses a frame tracer to perform a three-dimensional measurement of the frame shape, and the frame tracer calculates the frame's tilt angle. (2) Once the tilt angle of the frame is calculated, the tilt mechanism of the frame tracer tilts the frame by the same angle as that tilt angle, so that the frame is horizontal for one eye. (3) The frame tracer measures the external shape of the frame while it is held horizontally. For example, the frame tracer measures the external shape of the frame by tracing the base (groove) of the rim into which the lens is fitted, and obtains the measurement result as the first frame shape. (4) The frame tracer acquires the second frame shape. For example, the frame tracer moves the contactor along the concave rim of the frame while pressing it against the inner circumference of the frame. The frame tracer maintains contact between the contactor and the frame and moves around the inner circumference of the frame to acquire the three-dimensional shape data of the frame. (5) The frame tracer converts the two acquired shape data into conventional frame shape data, and converts the shape data of the concave side of the frame rim into radius data in polar coordinates (r(θ)) (actually, it is the difference data at the previous measurement point) with the frame center of the outer shape data as the reference point. Based on the above, the frame tracer 50 generates contour data of the inner rim of the eyeglass frame.

[0023] Processing circuit 20 The following explanation of the treatment circuit 20 will be given using Figure 7 and other figures. Normally, this treatment circuit 20 processes both eye eyeglass lenses, but the following explanation will focus on the right eye. The processing circuit 20 built into the mobile terminal 10 includes: a subject image data acquisition means 21 that acquires image I data displayed on the display 16 from the camera 12 or the display 16; a rim inner edge contour data acquisition means 22 that acquires rim inner edge contour data from the frame tracer 50; a rim inner edge contour image data adjustment means 23 that receives data from the subject image data acquisition means 21 and the rim inner edge contour data acquisition means 22 and adjusts the rim inner edge contour image data so that the rim inner edge contour image on the display 16 becomes an accurate and clear image; and a conversion coefficient calculation means 24 that recognizes bright spot images 12a, 12b, 12c, and 12d from the data from the subject image data acquisition means 21, calculates the distance between the bright spot images (between bright spot images 12a and 12b, and between bright spot images 12a and 12c) from the coordinates of their pixels, and calculates a conversion coefficient between the distance in the real object (based on data such as the distance between laser oscillators stored in memory M) and the distance in the image by comparing this with the actual distance.

[0024] The processing circuit 20 further includes a boxing center position XY coordinate calculation means 25 that calculates the XY coordinates of the boxing center position 8R (see Figure 8) based on the adjusted rim inner edge contour image data from the rim inner edge contour image data adjustment means 23; a pupil center position XY coordinate acquisition means 26 that recognizes the pupil center position 16R based on image data from the subject image data acquisition means 21 and acquires the XY coordinates of the pupil center position in pixels based on this recognition; a displacement amount calculation means 27 that receives boxing center position coordinate data from the boxing center position XY coordinate calculation means 25 and pupil center position coordinate data from the pupil center position XY coordinate acquisition means 26 and calculates the displacement amount of the pupil center position from the boxing center position (displacement amounts 17R, 18R (shown as representative of the right eye) expressed by the number of pixels in the X and Y directions); and a positioning means 28 that positions the boxing center at the pupil center position based on this calculated displacement amount.

[0025] The following describes the procedure for positioning the optical center of an eyeglass lens (the boxing center of the rim of the eyeglass frame) at the center of the pupil using a laser light irradiation device and an eyeglass lens positioning device using the same, with reference to Figure 8 (procedure flowchart), etc. First, the subjects are asked to select their preferred eyeglass frames (without lenses), put them on, and then remain in a designated position. The operator places the mobile terminal 10, to which the laser beam irradiation device 40 is attached, approximately 50 cm in front of the subject, and activates the laser beam irradiation device 40 to irradiate the subject's face with four laser beams (step S1). At this time, the laser beams L1 to L3 are positioned horizontally to the subject's forehead, and the central laser beam is positioned horizontally to the center of the forehead. As a result, bright spots Aa, Ab, and Ac appear as shown in Figure 5. Additionally, a bright spot Ad appears 50 mm below bright spot Aa (on the bridge of the subject's nose). This can be used to give instructions to correct problems such as the tilt of the subject's face. For example, based on the position of bright spot Ad, instructions such as "Your head is tilted to the right" can be given.

[0026] Next, the subject's face in this state is photographed with the camera 12 of the mobile device 10 (step S2). The resulting image is as shown in image I in Figure 2. The bright spots Aa, Ab, Ac, and Ad are displayed on the display 16 as bright spot images 12a, 12b, 12c, and 12d.

[0027] Next, in step S3, the conversion factor for image I on the display 16 is calculated. This calculation of the conversion factor begins by acquiring subject image data on image I from the mobile terminal 10 using the subject image acquisition means 21 of the processing circuit 20. From this data, the bright spot interval distance calculation means 22 measures the interval between bright spot images 12a and 12b, and between bright spot images 12a and 12c, as the number of pixels on the display 16. Then, the average value of these is calculated. If this average value is, for example, 500 pixels, then the interval between bright spots Aa and Ab, and between bright spots Aa and Ac is 50 mm, so 1 pixel corresponds to 0.1 mm, and from this, the conversion factor for 1 pixel of image I on the display 16 is 0.1 (by the conversion factor calculation means 23).

[0028] Once the aforementioned imaging is complete, the subject is asked to remove the eyeglass frames, and then the data (tracer data) of the inner edge contour of the rim of the eyeglass frames is acquired using the frame tracer 50 as described above (step S4). (Note that if there is a large discrepancy between the measurement center and the boxing center as measured by the frame tracer, the tracer data is corrected by the magnitude of the discrepancy between the measurement center and the boxing center, and the tracer data corrected to match the boxing center is used.)

[0029] Next, the tracer data is sent to the processing circuit 20 of the mobile terminal 10. In the processing circuit 20, the rim inner edge contour image data adjustment means 24 converts the values ​​of the tracer data into XY coordinate values ​​(unit: mm), and further converts them into the number of pixels in the XY direction using the conversion coefficient. This converted data is used to form tracer data-derived rim inner edge contour image data for displaying the rim inner edge contour on the display 16 (step S5).

[0030] Next, the rim inner edge contour image obtained from this tracer data is superimposed on the display 16 showing the subject's image captured by the camera. This display position is predetermined (default position), and if there is a discrepancy with the image captured by the camera, a person grips the subject to make fine adjustments to the discrepancy in the image to form a single image, thereby creating the most accurate final rim inner edge contour image possible (step S6). For this reason, it is preferable that the display 16 of the mobile terminal 10 used is a touch panel type.

[0031] Next, the XY coordinates of the boxing center position are calculated based on the image data obtained from the final inner rim contour image displayed and formed on the display 16 (step S7), and in parallel with this, the XY coordinates of the pupil center position are obtained from the pupil image on the display 16 (step S8). Generally, the XY origin of an image processed is in the upper left corner of the screen. For example, on a 1920 x 1080 pixel display image, the upper left corner is the point X=0 Y=0, and the lower right corner is the point X=1919 Y=1079. The explanation in this specification follows this convention. Here, let's assume that the coordinates of the boxing center position on the right eye side are X=700, Y=400, and the coordinates of the pupil center position are X=730, Y=380. The XY coordinates of the boxing center position are calculated as follows. First, for the X-direction, the value of the X-axis is obtained by dividing the sum of the largest and smallest values ​​of the X-axis from the XY coordinates of the entire circumference of the inner edge contour of the rim by 2. Similarly, for the Y-direction, the value of the Y-axis is obtained by dividing the sum of the largest and smallest values ​​of the Y-axis from the XY coordinates of the entire circumference of the inner edge contour of the rim by 2. Based on the above, the XY coordinate values ​​of the boxing center position are determined.

[0032] Calculating the displacement from the above XY coordinates (step S9), we get a displacement of dX = +30 in the X direction and a displacement of dY = -20 in the Y direction (see Figure 9). In terms of actual measurements, since the conversion factor is 0.1, the actual displacements are dX = +3 mm and dY = -2 mm. By canceling out the X and Y displacements of the pupil center from the boxing center, and making the coordinates of the pupil center coincide with the coordinates of the boxing center, the boxing center (optical center of the lens) can be positioned at the XY coordinates of the pupil center (step S10).

[0033] The cutting of the material lens is performed based on processing tracer data obtained by reflecting the data acquired as described above (the data on the amount of deviation) into the tracer data.

[0034] The spectacle lens positioning device of the present invention, having the above configuration, is highly portable, does not require auxiliary tools for measurement, is easy to operate and highly portable, and can precisely position spectacle lenses relative to spectacle frames, thereby improving the accuracy of lens positioning and processing adjustment during spectacle manufacturing. Furthermore, since the measurements are performed without contact with the subjects, it is also effective in reducing the burden of measurement on the subjects.

[0035] Although the above description has focused on single-focus lenses, the present invention is also applicable to progressive multifocal lenses. In the case of progressive multifocal lenses, for example, the pupillary center and optical center should be defined as the pupillary center and optical center for distance vision, and the near vision optical center should be considered (so that the near vision optical center of the lens fits within the rim of the eyeglass frame) when performing the positioning described above. [Explanation of symbols]

[0036] 10 Mobile devices 12 cameras 16 displays 20 Processing Circuits 40 Laser light irradiation device 41 Irradiation device main unit 42 Casing 43-46 First, second, third, and fourth laser oscillators 50 Mounting Adapters 52 Upper adapter 54 Lower adapter 56 Expandable member 60 Frame Tracer 8R Right eye lens, boxing focused 8L left eye lens, boxing-focused. 12a, 12b, 12c, 12d bright spots 16R, 16L pupil center 17R, 17L: X-axis displacement (inward shift) of the pupil center relative to the boxing center. 18R, 18L: Y-axis deviation of the pupil center relative to the boxing center (elevation height)

Claims

1. A laser beam irradiation device is used in conjunction with a pupil center position determination and measurement device that uses a mobile terminal, which is a tablet PC, to determine and measure the position of the pupil center of a subject's eye relative to the inner edge contour of the rim of an eyeglass frame, and is used to measure the scale ratio of the image displayed on the screen relative to the actual object, and the device irradiates the face of a subject with laser light, which is used to determine the scale ratio of the image displayed on the screen relative to the actual object, and comprises a casing equipped with four laser oscillators to cause four bright spots to appear on the subject's face with the laser light, and a mounting adapter for attaching the casing to the mobile terminal so that the distance between the camera lens of the mobile terminal and the subject is the same as the distance between the laser oscillators and the subject. The four laser oscillators consist of a central first laser oscillator that emits a first laser beam representing a first bright spot on the subject's face, second and third laser oscillators positioned one on each side of a horizontal line including the central laser oscillator, which emit second and third laser beams representing a second and third bright spot on the subject's face, and a fourth laser oscillator positioned directly below the first laser oscillator in a vertical direction, which emits a fourth laser beam diagonally downward to represent a fourth bright spot on the subject's face. The aforementioned mounting adapter attaches the casing to the mobile terminal by clamping the frame portion of the mobile terminal between the upper and lower adapter members. The upper adapter member and the lower adapter member have a variable distance between them due to an expandable / contractible member, thereby allowing them to accommodate the size of the mobile device, and further The mounting adapter has an upper adapter member and a lower adapter member, and the distance between them is variable by an expandable / contractable member. This allows for adjustment of the lateral position of the casing. This adjustment function allows the mounting adapter to be positioned so that the optical axes of the first and fourth laser beams emitted by the first and fourth laser oscillators lie on a vertical line that includes the optical axis of the camera lens of the mobile terminal. A laser light irradiation device characterized by the following features.

2. The laser light irradiation device according to claim 1, wherein the distance between the first laser oscillator and the second laser oscillator, and the distance between the first laser oscillator and the third laser oscillator are equal.

3. The laser light irradiation device according to claim 2, wherein the distance between the two laser oscillators is 10 mm to 100 mm.

4. The laser light irradiation device according to claim 2, wherein the distance between the two laser oscillators is 50 mm.

5. The laser light irradiation device according to claim 1, wherein when the laser light irradiation device is located at a predetermined distance from the subject, the fourth laser oscillator emits the fourth laser light at an angle such that the distance between the fourth bright spot and the first bright spot is equal to the distance between the second, third bright spots and the first bright spot.

6. The laser light irradiation device according to claim 1, wherein the laser light emitted from each of the aforementioned laser oscillators is of Class 1 according to JIS C 6802:2014 and is visible light that meets safety standards.

7. The laser light irradiation device according to claim 1, wherein the oscillation wavelength of each of the laser oscillators is in the 635 nm band.

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