Three-dimensional glasses

Abstract

To provide three-dimensional glasses that can reduce a fatigue feeling of an operator in a three-dimensional endoscope surgery.SOLUTION: Three-dimensional glasses 10 include: a left eye optical filter 14a which transmits only a left-eye image in the left-eye image and a right-eye image displayed on a display screen of an image display device; a right eye optical filter 14b which transmits only the right-eye image in the left-eye image and the right-eye image; a left eye optical plate 16a which is arranged so as to overlap with the left eye optical filter 14a in the light transmission direction; and a right eye optical plate 16b which is arranged so as to overlap with the right eye optical filter 14b in the light transmission direction. The left eye and right eye optical plates 16a, 16b include a central region 21 where an average frequency varies to a minus side as being apart from an optical center O, and a peripheral region 22 in which a slope of the average frequency line per 1 degree of a visual angle is equal to or less than 0.01 diopter as an absolute value on an outer side relative to the central region 21.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to stereoscopic glasses suitable for use in stereoscopic endoscopic surgery. [Background technology]

[0002] Three-dimensional display of images, such as 3D movies and 3D televisions, has been put to practical use. Most of these are binocular 3D displays using 3D glasses. Visual fatigue caused by convergence accommodation conflict is considered to be a problem with such binocular 3D displays.

[0003] As a means for reducing visual fatigue caused by convergence accommodation conflict with a simple configuration, it is effective to incorporate a wide focal lens with a refractive power (power) changed in a direction perpendicular to the optical axis into the stereoscopic glasses, as proposed by the inventors of the present invention in the following Patent Document 1. By viewing stereoscopically through a wide focal lens, the range of stereoscopic images that can be viewed comfortably in stereoscopic view is expanded, and visual fatigue of the user can be reduced. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] International Publication No. WO2020 / 008804 Summary of the Invention [Problem to be solved by the invention]

[0005] Meanwhile, in the field of endoscopic surgery, stereoscopic endoscopes that display images of the surgical site in 3D are being used. In the case of 3D movies and 3D television, the user continues to watch the 3D images, whereas in 3D endoscopic surgery using a stereoscopic endoscope, the surgeon must perform surgery while watching multiple 3D monitors placed in different positions, and must obtain various information from the surrounding situation other than the 3D monitors during surgery, which requires the user, the surgeon, to move his or her line of sight widely. For this reason, if distortion occurs in the peripheral area of ​​the lenses built into the 3D glasses, it causes the surgeon to feel strange and uncomfortable, which is one of the factors that increases the surgeon's fatigue. SUMMARY OF THE PRESENT EMBODIMENT The present invention has been made to solve the above-mentioned problems, and has an object to provide stereoscopic glasses capable of reducing the fatigue felt by an operator during stereoscopic endoscopic surgery. [Means for solving the problem]

[0006] The stereoscopic glasses according to the first aspect of the present invention include: a left-eye optical filter that transmits only the left-eye image with respect to the left-eye image and the right-eye image displayed on a display screen of an image display device; an optical filter for a right eye that transmits only the image for the right eye with respect to the image for the left eye and the image for the right eye; a left-eye optical plate disposed so as to overlap the left-eye optical filter in a light transmission direction; A pair of stereoscopic glasses for use in stereoscopic endoscopic surgery, comprising: a right-eye optical filter and a right-eye optical plate arranged so as to overlap in a light transmission direction; The left-eye and right-eye optical plates are A central region where the average power changes to the negative side as the distance from the optical center increases; A peripheral region is provided outside the central region, in which the absolute value of the inclination of the mean power line per 1 degree of visual angle is 0.01 diopters or less.

[0007] According to the stereoscopic glasses of the first aspect defined in this manner, the range of convergence in which stereoscopic images can be viewed comfortably can be expanded in front of the image display device by observing the stereoscopic image through the central region of the optical plate, thereby reducing visual fatigue caused by convergence accommodation inconsistencies, and image distortion in the peripheral region of the optical plate can be suppressed, thereby preventing the occurrence of discomfort and odd sensations caused by image distortion, thereby reducing the fatigue of the surgeon during stereoscopic endoscopic surgery.

[0008] Here, the central area can be configured to include an imaginary circular area with a visual angle of 15 degrees. In this case, the amount of change in power within the range from the optical center to a visual angle of 15 degrees can be 0.25 to 0.40 diopters in absolute value.

[0009] The central area can be configured to include an imaginary circular area with a visual angle of 25 degrees. In this case, the amount of change in power within the range from the optical center to a visual angle of 25 degrees can be set to an absolute value of 0.49 to 0.64 diopters.

[0010] The central area can be configured to include an imaginary circular area with a visual angle of 35 degrees. In this case, the amount of change in power within the range from the optical center to a visual angle of 35 degrees can be set to an absolute value of 0.79 to 0.94 diopters.

[0011] The optical plates for the left and right eyes, whose powers have been changed as described above, have a z-axis that is the axis in the front-to-back direction passing through the optical center, and a positive z-axis that is the direction toward the rear of the optical plate. In this case, the z-coordinate value of at least one of the front and rear surfaces of the optical plate is a3r 3 +a4r 4 +a6r 6 +a8r 8 +a 10 r 10 (where r is the distance from the z-axis, a3, a4, a6, a8, a 10 This can be achieved by adding an aspheric component represented by (where, is a constant).

[0012] In the present invention, the optical plates for the left and right eyes may further include prescription power components for correcting at least one of myopia, hyperopia, and astigmatism. [Brief description of the drawings]

[0013] [Figure 1] FIG. 1 is a diagram showing a configuration of stereoscopic glasses according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a diagram showing the optical plate in FIG. 1, in which (A) is a front view and (B) is a vertical cross-sectional view. [Diagram 3] FIG. 1 is a diagram for explaining the relationship between accommodation and convergence. [Figure 4] 11 is a diagram showing a change in average dioptric power along a direction perpendicular to the optical axis of the optical plate. [Diagram 5] (A) is a photograph of the target at a different position without the optical plate, and (B) is a photograph of the target at a different position through the optical plate. [Figure 6] FIG. 5 is a diagram showing a change in average frequency different from that shown in FIG. 4. [Figure 7] FIG. 7 is a diagram showing a change in the average frequency different from that shown in FIG. 4 and FIG. [Figure 8] FIG. 13 is a diagram showing a modified example in which the left and right optical filters are configured as an integrated eye shield. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Next, stereoscopic glasses according to an embodiment of the present invention will be described with reference to the drawings. In FIG. 1, reference numeral 10 denotes stereoscopic glasses used for binocular stereoscopic display, more specifically, stereoscopic glasses used for stereoscopic endoscopic surgery. The stereoscopic glasses 10 have a frame 12 to which a left-eye optical filter 14a and a right-eye optical filter 14b are attached. A left-eye optical plate 16a and a right-eye optical plate 16b are attached in front of the left-eye optical filter 14a and the right-eye optical filter 14b (opposite side to the eyeball) or behind (toward the eyeball) the left-eye optical filter 14a and the right-eye optical filter 14b at positions overlapping the optical filters 14a and 14b, respectively. In the following description, the left-eye optical filter 14a and the right-eye optical filter 14b may be simply referred to as "optical filters 14". The left-eye optical filter 16a and the right-eye optical plate 16b may be simply referred to as "optical plate 16".

[0015] The optical filters 14a and 14b have a function of selectively transmitting the left-eye image and the right-eye image, respectively. In the stereoscopic glasses 10, for the left-eye image and the right-eye image displayed on the display screen of a 3D monitor (image display device) (not shown), the light related to the right-eye image is blocked by the left-eye optical filter 14a, and only the light related to the left-eye image is transmitted through the left-eye optical filter 14a. Also, the light related to the left-eye image is blocked by the right-eye optical filter 14b, and only the light related to the right-eye image is transmitted through the right-eye optical filter 14b. Therefore, the left eye image is seen by the user's left eye 18a, and the right eye image is seen by the user's right eye 18b.

[0016] In this example, the optical filters 14a and 14b are composed of polarizers corresponding to the polarization method. In the binocular stereoscopic display, the method for separating the left and right images includes the polarization method, the liquid crystal shutter method, and the spectral filter method, and it is also possible to compose the optical filters 14a and 14b with the liquid crystal shutter or the spectral filter.

[0017] 2 shows the optical plate 16, where (A) is a front view of the optical plate 16 and (B) is a vertical cross-sectional view of the optical plate 16. This optical plate 16 has a shape before its outer shape is processed to match the shape of the frame 12, and has a circular shape when viewed from the front. In the following description, the "upper" and "lower" directions of the optical plate 16 refer to the "upper" and "lower" directions of a user wearing the stereoscopic glasses.

[0018] As shown in FIG. 2(A), the optical plate 16 has a central region 21, a peripheral region 22 provided outside the central region 21, and an intermediate region 23 located between the central region 21 and the peripheral region 22.

[0019] The central area 21 is an area including the optical center O of the optical plate 16 and is used for stereoscopic vision. As described in the above Patent Document 1, in stereoscopic vision, if the convergence position and the accommodation position match, visual fatigue due to convergence accommodation conflict does not occur. However, in order to realize comfortable stereoscopic vision without visual fatigue, it is known that the convergence position and the accommodation position do not need to match perfectly, and there is a certain tolerance range for the match between the convergence position and the accommodation position.

[0020] FIG. 3 is a diagram showing the relationship between convergence and accommodation. In this figure, the horizontal axis shows convergence, and the vertical axis shows accommodation. The unit is diopter (D), which is the reciprocal of the distance expressed in meters. Even if convergence and accommodation do not match, they can be expressed as the diopter shown in FIG. far and D near In other words, there is a tolerance for the agreement of convergence and accommodation that realizes comfortable stereoscopic vision. Here, the display area of ​​a stereoscopic image that can be viewed comfortably is the distal end D, which corresponds to the depth Dv perceived by convergence. far and proximal end D near It can be expressed using D far ,D near Using Dv, D far =1.129D v +0.442...Equation (1) D near =1.035D v -0.626...Equation (2) It is given that:

[0021] For example, suppose the observation distance to the screen (display screen) of a 3D monitor in a stereoscopic endoscopic surgery is 1.4 m (0.71 D). If the eyes are focused at this observation distance, D is calculated by the formulas (1) and (2). far =0.71D, D near = 0.71D, where D v , the range of convergence M1 for comfortable stereoscopic vision is found to be 0.77 m (1.3D) to 4.1 m (0.24D). Considering that stereoscopic images are mainly displayed on the front side of the 3D monitor in stereoscopic endoscopic surgery, it is important to eliminate the uncomfortable area (area where convergence accommodation conflict occurs) that exists on the front side of the 3D monitor in order to reduce the surgeon's visual fatigue. In this case, by extending the range (depth of field) where the optical plate 16 is considered to be in focus on the front side of the 3D monitor, the area where comfortable stereoscopic vision without visual fatigue is possible can be expanded on the front side of the 3D monitor.

[0022] For example, when the focal length during observation through the optical plate 16 is changed in the range of 6.25 m (-0.16 D) to -∞ (0 D), the range in which the eye can focus is 0.71 D to 0.87 D. far =0.71D, D near = 0.87D as D v , the range of convergence M2 that allows comfortable stereoscopic viewing expands to 0.69 m (1.44D) to 4.1 m (0.24D). In other words, it can be seen that the comfortable area expands in front of the 3D monitor. For this reason, in this example, the average diopter in the central area 21 is changed to the negative side as it moves away from the optical center O, thereby extending the depth of field of the optical plate 16 to the front side of the 3D monitor.

[0023] FIG. 4 is a diagram showing the change in average power along the direction perpendicular to the optical axis of the optical plate 16. As shown in FIG. The visual angle α shown in the figure indicates the angle when the center of the eyeball is located 25 mm away from the refractive surface on the rear side of the lens on the optical axis of the optical plate 16, and the value of the visual angle α increases toward the peripheral edge of the optical plate 16 (see FIG. 2(B)).

[0024] 4, central region 21 including optical center O is sized to include an imaginary circular region with a visual angle of 25 degrees, and the average diopter in central region 21 changes approximately linearly on the negative side from optical center O toward the peripheral edge of the optical plate. More specifically, the amount of diopter change L1 (see FIG. 4) within the range from the optical center O to a visual angle of 15 degrees is an absolute value of 0.25 to 0.40 diopters, and the amount of diopter change L2 within the range from the optical center to a visual angle of 25 degrees is an absolute value of 0.49 to 0.64 diopters.

[0025] By increasing the amount of power change, the area in which comfortable stereoscopic vision is possible can be expanded, but if the amount of power change is too large, the image resolution decreases. For this reason, in this example, the amount of power change is specified as above, taking into consideration the range in which a stereoscopic image is actually displayed in a stereoscopic endoscopic surgery.

[0026] On the other hand, the peripheral region 22 outside the central region 21 is a region of constant power with reduced power change in order to reduce image distortion at the periphery of the optical plate. In this example, as shown in the partially enlarged view of FIG. 4, the slope β of the mean power line in the peripheral region 22 of the optical plate 16 is specified to be 0.01 diopters or less per 1 degree of visual angle in absolute value. It is preferably 0.005 diopters or less, and more preferably 0.0025 diopters or less. As shown in Figure 4, the mean power line gradually changes to the negative side at a substantially constant slope in the central region 21, and the slope gradually decreases in the intermediate region 23 between the central region 21 and the peripheral region 22, so that the mean power is substantially constant in the peripheral region 22. Such a change in the average power in the direction perpendicular to the optical axis can be obtained by adding an aspheric component to at least one of the front and rear surfaces of the optical plate 16.

[0027] Next, the shape of the optical plate 16 will be described. As shown in Fig. 2, the rear surface 25 of the optical plate 16 is a concave surface defined by formula (i), and the front surface 26 is a convex surface defined by formula (ii). The axis in the front-rear direction passing through the optical center O of the optical plate 16 (base point O1 on the rear surface 25, and base point O2 on the front surface 26) is defined as the z-axis, and the direction toward the rear of the optical plate 16 is defined as the positive direction of the z-axis. The z-axis coincides with the optical axis of the optical plate 16.

[0028] z=r 2 / (R1+(R1 2 -Kr 2 ) 1 / 2 ) + δ ... formula (i) z=r 2 / (R2+(R2 2 -Kr 2 ) 1 / 2 ) …Formula (ii)

[0029] In the formulas (i) and (ii), r is the distance from the z-axis. In other words, when considering an orthogonal coordinate system with the base point O1 at the rear surface 25 and the base point O2 at the front surface 26 as the center, and the left-right direction and the up-down direction perpendicular to the z-axis as the x-axis and y-axis, respectively, r=(x 2 +y 2 ) 1 / 2 where R1 and R2 are the radii of curvature at the vertices of the surface, and K is the Conic coefficient. The rear surface 25 of the optical plate 16 has a rotationally symmetric aspheric shape represented by the above formula (i). In the formula (i) that defines the rear surface 25, δ is a 3 +a4r 4 +a6r 6 +a8r 8 +a 10 r 10 (where r is the distance from the z-axis, a3, a4, a6, a8, a 10 is a constant). Therefore, in the optical plate 16 of this example, the front surface 26 is spherical and the rear surface 25 is aspheric. Note that R1 and R2 are determined by the prescribed power (0D in this example).

[0030] For example, the change in average power shown in FIG. 4 is obtained by defining the constants in the above formulas (i) and (ii) as follows for an optical plate 16 having a center thickness of 2.1 mm and made of a material with a refractive index n of 1.608: Rear radius of curvature R1: 146.78mm, front radius of curvature R2: 147.57mm, K: -0.6, a3: 1.84×10 -05 , A4:8.10×10 -08 , a6:-3.79×10 -10 , a8:2.79×10 -13 , a 10 :-7.42×10 -17

[0031] FIG. 5 shows the effect when the optical plate 16 is used. The evaluation was performed as follows. Optotype 1 labeled "SCREEN" was placed at a distance of 1.4 m (corresponding to the distance to the display screen of a 3D monitor) in front of the lens of a camera with an entrance pupil diameter of 5 mm, which is the average pupil diameter of a human being, and optotype 2 labeled "3D IMAGE" was placed at a distance of 1.15 m (corresponding to the distance to the displayed stereoscopic image). Optotype 1 and optotype 2 were photographed with the camera focused on optotype 2. (A) in FIG. 5 is a photograph of the optotype without the optical plate, and (B) is a photograph of the optotype through the optical plate 16.

[0032] Comparing (A) and (B) in Figure 5, in (A) without the optical plate, the characters of the visual target 1 look blurred, whereas in (B) with the optical plate, the appearance of the characters of the visual target 1 is clearer than in (A), and there is little change compared to the characters of the focused visual target 2, and it can be seen that there is a large difference in the depth of field between (A) and (B). In other words, the use of the optical plate 16 expands the range that can be focused, and therefore the range in which comfortable stereoscopic vision can be achieved when viewing in stereoscopic vision can also be expanded.

[0033] According to the stereoscopic glasses 10 configured as described above, by observing a stereoscopic image through the central region 21 of the optical plate 16, the area in which stereoscopic vision is good can be expanded, and image distortion in the peripheral region 22 of the optical plate 16 can be suppressed, thereby reducing the fatigue of the surgeon caused by convergence accommodation inconsistencies and image distortion during stereoscopic endoscopic surgery.

[0034] In the present invention, the size of the central region 21 in the optical plate 16 can be changed as appropriate. FIG. 6 is a diagram showing the change in average power when the central region 21 of the optical plate 16 is made smaller and the region with constant power provided around the optical plate is made larger. In this example, the central region 21 is sized to include a virtual circular region with a visual angle of 15 degrees, and the absolute value of the power change amount L1 within the range from the optical center to the visual angle of 15 degrees is 0.25 to 0.40 diopters. Therefore, in the example of Fig. 6, the inclination of the average power line in the central region 21 is approximately the same as in Fig. 4, and the effect of expanding the range of convergence that allows comfortable stereoscopic viewing through the central region 21 to the front of the 3D monitor can be obtained in the same way as in Fig. 4. On the other hand, the peripheral region 22 with reduced power change is provided over a wider area than in Fig. 4, and the effect of suppressing distortion can be obtained over a wider area of ​​the optical plate 16.

[0035] For example, the change in average power shown in Figure 6 can be achieved for an optical plate 16 having a center thickness of 2.1 mm and made of a material with a refractive index n of 1.608 by defining the constants in the above equations (i) and (ii) as follows: K:-3.0, a3:2.22×10 -05 , A4:-2.86×10 -07 , A6: 4.24×10 -11 , a8:3.56×10 -14 , a 10 :-1.72×10 -17

[0036] FIG. 7 is a diagram showing the change in average power when the central region 21 of the optical plate 16 is enlarged in contrast to FIG. 6, and the region with a constant power provided around the optical plate is narrowed. In this example, central region 21 is sized to include an imaginary circular area with a visual angle of 35 degrees, and the absolute value of the amount of power change L1 within the range from the optical center to a visual angle of 15 degrees is 0.25 to 0.40 diopters, the absolute value of the amount of power change L2 within the range from the optical center to a visual angle of 25 degrees is 0.49 to 0.64 diopters, and the absolute value of the amount of power change L3 within the range from the optical center to a visual angle of 35 degrees is 0.79 to 0.94 diopters. According to the example of Figure 7, it is possible to suppress image distortion around the optical plate, while achieving the effect of expanding the range of convergence in front of the 3D monitor, allowing comfortable stereoscopic viewing over a wider range than in the case of Figure 4 (i.e., even when the line of sight is shifted from the optical center).

[0037] For example, the change in average power shown in Figure 7 can be achieved in an optical plate 16 having a center thickness of 2.1 mm and made of a material with a refractive index n of 1.608 by defining the constants in the above equations (i) and (ii) as follows: K: 0.2, a3: 1.84 x 10 -05 , A4:-1.88×10 -08 , a6:-6.21×10 -12 , a8:-6.85×10 -14 , a 10 :3.53×10 -17

[0038] Although the embodiment of the present invention has been described in detail above, this is merely an example, and the present invention can be embodied in various modified forms without departing from the spirit of the present invention. For example, in the above embodiment, separate left and right optical filters are attached to the frame, but it is also possible to configure the left and right optical filters as an integrated eye shield 40 as shown in Fig. 8. This can improve the effect of protecting the eyes of the surgeon from splashes of blood and the like. In the above embodiment, an aspherical component is added to the rear surface of the optical plate, but in some cases an aspherical component may be added to the front surface of the optical plate, or it is also possible to add aspherical components to both the front and rear surfaces. In the above embodiment, the peripheral region of the optical plate is an area with constant power over the entire circumference, but in some cases it is possible to provide an area with constant power only over a portion of the circumference. In the above embodiment, plano lenses with essentially no prescription are used as the optical plates for the stereoscopic glasses, but it is also possible to further add a power component to the optical plate to correct at least one of myopia, hyperopia, and astigmatism. In addition, in the above embodiment, the optical filter and the optical plate are configured as separate bodies, but in some cases it is also possible to configure the optical filter and the optical plate as a single body by, for example, laminating a polarizing film equivalent to the optical filter inside the optical plate. [Explanation of symbols]

[0039] 10 Stereoscopic Glasses 14, 14a, 14b Optical filters 16,16a,16b Optical plate 21 Central area 22 Surrounding Areas L1, L2, L3 degree change O optical center α viewing angle β Slope of the mean frequency line

Claims

1. a left-eye optical filter that transmits only the left-eye image with respect to the left-eye image and the right-eye image displayed on a display screen of an image display device; an optical filter for a right eye that transmits only the image for the right eye with respect to the image for the left eye and the image for the right eye; a left-eye optical plate disposed so as to overlap the left-eye optical filter in a light transmission direction; A pair of stereoscopic glasses for use in stereoscopic endoscopic surgery, comprising: a right-eye optical filter and a right-eye optical plate arranged so as to overlap in a light transmission direction; The left-eye and right-eye optical plates are A central region where the average power changes to the negative side as the distance from the optical center increases; The stereoscopic glasses further include a peripheral region on the outside of the central region, the peripheral region having an absolute value of a gradient of the mean power line per 1 degree of visual angle of 0.01 diopters or less.

2. 2. The stereoscopic glasses according to claim 1, wherein the central region includes an imaginary circular region having a visual angle of 15 degrees, and the amount of change in power within a range from the optical center to the visual angle of 15 degrees is 0.25 to 0.40 diopters in absolute value.

3. 3. The stereoscopic glasses according to claim 2, wherein the central region includes an imaginary circular region having a visual angle of 25 degrees, and the absolute value of the change in power within a range from the optical center to the visual angle of 25 degrees is 0.49 to 0.64 diopters.

4. 4. The stereoscopic glasses according to claim 3, wherein the central region includes an imaginary circular region having a visual angle of 35 degrees, and the absolute value of the change in power within a range from the optical center to a visual angle of 35 degrees is 0.79 to 0.94 diopters.

5. The optical plates for the left and right eyes have a z-axis that is a front-back axis passing through the optical center, and a positive direction of the z-axis that is a direction toward the rear of the optical plate. In this case, the z-coordinate value of at least one of the front surface and the rear surface of the optical plate is a 3 r 3 +a 4 r 4 +a 6 r 6 +a 8 r 8 +a 10 r 10 (where r is the distance from the z axis, a 3 , a 4 , a 6 , a 8 , a 10 5. The stereoscopic glasses according to claim 2, further comprising an aspheric component expressed by:

6. The stereoscopic glasses according to claim 5, wherein the left-eye and right-eye optical plates further include prescription power components for correcting at least one of myopia, hyperopia, and astigmatism.

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