JP2014026012A - Glasses-free stereoscopic (3d) video system and its adapter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable a user to enjoy natural 3D video that has depth perception and three-dimensional effect (volume effect) with less 3D fatigue without using special electronic apparatus due to an ordinary 2D video.SOLUTION: The foregoing problem is solved by a 3D adapter comprising an extremely thin Fresnel lens according to the invention and a compact frame able to hold the Fresnel lens between two shapes, one being a curved shape and the other a flat shape. Accordingly, both depth perception and three-dimensional effect required for 3D vision are achieved by the Fresnel lens that has a curved face designed in an appropriate shape.It can also be used as a focus adjustment function, providing a natural video with the result that fatigue is decreased.The device is designed for use in 3D viewing with, mainly, a portable video display (e.g., smart phone, tablet PC, and portable game machine). Therefore, portability is essential. The Fresnel lens with extreme thickness (not greater than 0.8 mm) makes it possible to decrease flexural stress and eliminates image distortion. Accordingly, when viewing, 3D viewing is enjoyed with the Fresnel lens curved, and when not viewing, it can be made flat. Therefore, natural 3D can be enjoyed even with a portable video device.

Description

The present invention relates to an autostereoscopic (3D) video apparatus and an adapter for the autostereoscopic (3D) video apparatus that can be viewed as if they are stereoscopic.

Stereoscopic images are transmitted using two different images (parallax) for the left eye and right eye, and the left and right eye images are transmitted and combined on the receiver side into a single stereoscopic image. On the other hand, stereoscopic viewing is performed using special glasses for stereoscopic viewing and a lens (lenticular lens) processed with high accuracy in the naked eye method. This method always requires two screens for the right eye and left eye, and requires special electronic equipment and optical parts processed with high precision. Furthermore, since the left and right screens are alternately displayed in a time-division manner or finely divided, the image quality is greatly degraded due to flickering of the screen, halving of the number of pixels, and the like. The present invention realizes a stereoscopic (3D) image without dividing a normal plane image electronically into separate left and right screens, no special electronic equipment, and no deterioration due to a reduction in the number of pixels with the naked eye. is there.

International Patent Literature Patent 4365435 European Patent Application Publication No. 1 636 631 GB2392808 (A) Patent Publication JP 07-333557 A Utility Model No. 3140743 Utility model No. 3147801 Patent publication JP 2000-56400 Patent 3579683

Japan Patent Office “FY2009 Patent Application Technology Trend Research Report Stereoscopic Television” H22.4 Quasar Technology Co., Ltd. “3D video with pseudo-parallax” / Masaharu Yamada / eizojoho industrial / June 2011) "Gathering for Gardner 3" / Jerry Andrus / Jan. 1998 "Make it mysterious! Trick art work" / Akika Kitaoka / Akane Shobo / 2011.07

The problem to be solved by the present invention is that normal 2D images can be enjoyed with natural 3D images with a sense of depth and three-dimensionality (volume feeling) with little “3D fatigue” without using special electronic devices. Is to do.

There are various factors that make people feel “3D”. Here, the reason for “3D sensation” is that when both “perspective” and “three-dimensional sensation” are both provided, the natural scenery is viewed. Both were considered as “3D (three-dimensional) feeling”. The following items (1) to (8) are elements of “perspective”, and the items (6) to (8) are elements that feel “stereoscopic” while overlapping. Even if it is a plane paper, if it is viewed obliquely, the 1D (one-dimensional) at the front side increases to 3D (three-dimensional) in addition to the upper, lower, left and right 2D (two-dimensional). Therefore, a sense of perspective (perspective) and a stereoscopic effect (volume) are combined to give a three-dimensional feeling (3D feeling).
(1) Perspective (perth) becomes narrower as it goes farther away, like a tree-lined road that continues straight away, and eventually disappears to one point (disappearance point).
(2) Even if it is the same size, the front is large and the back is small.
(3) Like the scenery seen from the train window, the foreground moves fast and the distance moves slowly.
(4) The overlapping object is hidden in the foreground and the hidden object is in the back.
(5) Since the light fluctuates in the air, the near area is clearly visible in the distance.
(6) When looking at nearby objects, the eye lens should be thicker and thinner and focused.
(7) A viewing angle effect that makes the object appear shorter than the actual angle as it becomes oblique to the line of sight. Drawing in short when performing two-dimensional projection is called a shortening method. When viewed with both eyes, the degree of shortening varies between the left and right eyes.
(8) When an object is viewed with the left and right eyes, the angle (convergence angle) formed by the lines of sight between the left eye and the object, and the right eye and the object is close and large. Therefore, the near part is a close eye and the far part is parallel. An object at a distance other than the convergence angle is doubled in front and back.
(9) When a relatively close object is viewed with the left and right eyes, the left eye looks wider on the left side than the right side of the object, and the right eye looks wider on the right side. Distant objects have small differences and cannot be distinguished further.

Among the above (1), the shortening method from (1) to (7) is an element that feels 3D feeling with one eye. If you look at the natural scenery with both eyes, you will feel 3D. At that time, even if one eye is closed, the 3D feeling disappears and the landscape does not suddenly become flat. This is because a 3D feeling is felt by the elements (1) to (7). A three-dimensional feeling (volume feeling) is not always necessary. Therefore, even with 2D (planar) photographs and video equipment, if you pay attention to these elements, you can create a 3D video. If the image is just a distant view, there is no need for a volume, so even a flat 2D image may have a 3D effect. If the image quality (dots of the pixels that make up the screen) is low, what you see is made up of dots, so the brain may recognize even if it is a plane because it is surely displayed on the display . If the image quality becomes high, the sense of dots disappears and the brain cannot be distinguished from seeing a natural landscape. Even if a display such as a movie or a television is flat and has a 3D feeling, the brain may be recognized as 3D even if there is a dot feeling.

The convergence angle of 8) is an element used by current 3D movies and 3D televisions. Perspective can be obtained by creating two images and changing the interval between the images visible to the left and right eyes. In order to make the two images look like only the left eye for the left eye and only the right eye for the right eye, 3D glasses are required. When the left and right images overlap each other, the image appears to be equal to the distance to the display. When the image for the right eye is moved to the right and the image for the left eye is moved to the left with reference to the display unit, the left and right line of sight are combined in the back rather than the display unit, so the image appears to be in the back. . On the contrary, when the image for the right eye is moved to the left and the image for the left eye is moved to the right, the left and right line of sight are combined in front of the display so that the image appears to be in front. However, since the display is flat, there is no element to move the lens for focus adjustment (6), and the 3D feeling is reduced, and the human has never experienced "the convergence angle is changed frequently without changing the thickness of the lens. (I often get close to it.) ” For this reason, it can cause “3D fatigue” and it can be tired when viewed for a long time.

Furthermore, in the distant view, the left and right images move away, but if the distance between the human eyes exceeds about 6 cm, the eyes will move which has never been experienced in human history. When looking at a close object, a person has a close eyesight and when looking at a distant object, the line of sight is almost parallel, and even when looking at the farthest star in the night sky, he has only moved to the point where the line of sight is parallel. Considering the size of the display screen, the farthest starry sky is 6cm, which is the distance between the eyes, and the child is narrow and 5cm, so the video should be made to be less than 5cm, but it is projected on an unexpectedly large screen. In that case, the left and right lines of sight are parallel and wide angle, so it is not known whether there is any adverse effect on the eyes.

The element (8) can be obtained by photographing with two cameras or two cameras separated by the same distance as the distance between eyes. However, since the convergence angle of (7) is fixed at a certain position, a certain distance can be expressed, but the other distance becomes an uncomfortable image. There is also a method of adjusting while photographing the angle corresponding to the convergence angle of two cameras or two eyes, but the viewer does not always look in the direction, so there is a possibility that the image will be unnatural. . Even in this case, the display device is flat and does not adjust the focus of the element (6). The integral photography method is expected to satisfy the elements (1) to (8) at the same time. However, as described above, it is still an experimental stage and requires complicated and expensive special electronic equipment. .

With the autostereoscopic (3D) video adapter of the present invention, the problem of satisfying all of the elements (1) to (8) that feel the 3D feeling with the naked eye without the need for conversion software or special electronic devices for ordinary 2D video is required. Solved. Unlike the conventional 3D video that relies on the “convergence angle (degree of crossing)”, the present invention changes the visible area according to the viewing angle in addition to the “convergence angle” and performs the eye focus adjustment operation so that the brain recognizes the 3D feeling. The ability is used to achieve a natural 3D feeling that has never been seen before.

With the autostereoscopic (3D) video apparatus and adapter of the present invention, a normal 2D display can be enjoyed as a pseudo 3D display. In addition, if the adapter of the present invention is attached to conventional video equipment such as a TV, a personal computer, and a tablet terminal, ordinary 2D video can be enjoyed as natural 3D video at low cost and easily. There is no need for expensive 3D-only video software, electronic equipment, 3D-compatible equipment, or glasses.

It is composition explanatory drawing of this invention apparatus. It is an example of the form at the time of non-viewing, carrying and operating the device of the present invention. It is another example of the form when the device of the present invention is not viewed, carried or operated. It is explanatory drawing of a perspective method. It is explanatory drawing of the three-dimensional effect by parallax. It is explanatory drawing of the perspective by a viewing angle. It is explanatory drawing which looked at the path of the light of the image | video of this invention from the upper surface. It is explanatory drawing of the principle from which a perspective appears in this invention. It is explanatory drawing of the principle which a three-dimensional effect (volume feeling) comes out near the center of an image | video by this invention. It is explanatory drawing of the principle in which a three-dimensional effect (volume feeling) comes out near the both ends of an image | video by this invention. FIG. 3 is a comprehensive explanatory diagram showing that a 2D image looks like a natural 3D image in the present invention. This is an example using one Fresnel lens having a relatively uniform thickness according to the present invention. The present invention is an embodiment in which a Fresnel lens is arranged on a curved surface portion of a kamaboko type whose one side is flat and the opposite side is semicylindrical. It is the Example which has arrange | positioned the Fresnel lens in the curved surface part of the concave lens shape opposite to the kamaboko type | mold of this invention. It is the Example which installed the some Fresnel lens of this invention. This is an example in which the display of the present invention and the Fresnel lens are relatively inclined and the vertical curvature is changed. It is explanatory drawing which looked at the path | route of the light at the time of installing the display and Fresnel lens of this invention inclining relatively, and changing up and down curvature, from the side. It is the example of the dimension of the implementation which installed the display and the Fresnel lens relatively inclined.

When viewing a 2D image (image on the display), humans usually see the left and right eyes at the same distance and in the same shape when viewing any part of the image. Strictly speaking, the right eye is seen from the right about 3 cm, which is half the width of the eye from the center, and the left eye is also seen from about 3 cm from the left. Therefore, it should be possible to recognize the displayed image as a three-dimensional image from the left and right parallaxes. However, since the display is flat, the brain recognizes the image as a flat plane even if the projected video has left and right parallax. Similarly, the brain is recognized as a flat surface even in a video image with a sense of depth or a stereoscopic effect on the display. Recognizing it as a solid is an “illusion”. Therefore, the key point is how to make the brain "illusion" with a flat display.

The present invention uses a Fresnel lens. The normal way to use a Fresnel lens is to place it in front of the screen at a distance of several centimeters to several tens of centimeters below the focal length, and from above the distance at which objects can be clearly seen from the eyes (defined as the clear vision distance is defined as 25 cm). When you look at the screen, the screen appears enlarged. However, the 2D image can only be seen as an enlarged 2D image. Invisible in 3D video. The Fresnel lens is a single focus lens (collected at one point when a parallel light beam is applied). A rectangular Fresnel lens with a long transverse direction is narrowed in the transverse direction and bent into a convex shape close to a semi-cylindrical shape. Since the focal distance from each point of the Fresnel lens remains the same, the focal position of the Fresnel lens follows the deformation of the Fresnel lens. When this Fresnel lens is placed in front of the flat display, the distance between the image and the Fresnel lens is far from the center and near the left and right edges. When the image is viewed through the Fresnel lens with this arrangement, the size, relative position, shape, etc. of the image are different between the left and right eyes.

When the increased left and right parallax reaches the brain, the displayed image cannot be recognized as a plane. Since the left and right parallax are small, the brain cannot recognize even two objects. In order for the brain to match the eyelids, it recognizes that “the right and left images are different, so there must be a perspective or a three-dimensional object.” When looking at "trick art" or "foolish picture", the brain will recognize and convince you in the past direction and experience in an easy direction even if the perspective and unevenness are reversed. This is the “illusion”. For this reason, it can be regarded as a 3D image with a sense of depth and volume in spite of 2D images. Unlike conventional 3D images that have been artificially processed and overexaggerated, the present invention appears to be a very natural 3D image with a sense of perspective and volume because of its slight parallax. Because it is a natural 3D feeling and glasses are unnecessary, there is little fatigue feeling called “3D fatigue” and you can enjoy it with very easy-to-view images.

The adapter of the present invention can enjoy natural 3D images when a frame is attached to the front of the screen of a display device such as a TV, a personal computer, a tablet PC, and a smartphone for 2D images that are widely used, and the adapter is arranged. Since the adapter is made of an optical mechanism, you can enjoy 3D images easily and inexpensively on your own video display device by simply attaching it.

Because it uses a flexible Fresnel lens, it can be deformed flat from a semi-cylindrical shape when not viewing or carrying, so it is not bulky. There is no problem with touch panel operations on smartphones and tablet PCs.

In recent years, one of the causes of sluggish 3D relations is the need for special 3D shooting and special 3D viewing equipment, which requires additional production costs and is difficult to put effort into. If it becomes 3D as it is, 2D and 3D compatibility will be created, and there will be no cost risk to create content that expects 3D. Color broadcasting began in the days when there was only black and white TV, but the black and white TV house was black and white as it was, and the house where the color TV was bought was in excellent vertical compatibility where both families could see the same content in color. The present invention is the same, and the same content can be enjoyed both with and without a 3D adapter. In recent products, the relationship between hardware and software is a new product and the old version works, but the old product does not work. We are only thinking about upward compatibility, not up-down compatibility like TV. We are approaching consumers for replacement. In view of that, the present invention is considered to have the power to change the world's video display devices to 3D so that televisions all over the world can shift from black and white to color without changing the content. There is no need to spend a lot of money on public relations alone for years when terrestrial digital transitions where old TV can no longer be seen.

In recent years, supermarket sales floors also have a small display at each corner, and are always playing promotional videos of products. By simply attaching the autostereoscopic (3D) video adapter of the present invention to this display, the 2D video becomes a 3D video and the effect of attracting customers and sales is greatly improved. Of course, customers do not need to wear glasses to view 3D images.

Since the autostereoscopic (3D) video adapter of the present invention can be attached to almost all conventional video display devices, it is said that “3D is normal” when 2D is normal for images projected on a display such as a television. It will change into the world.

FIG. 1 shows the mechanism of the device of the present invention. The adapter 11 is installed in front of the video display device 13. This adapter has a laterally curved curvature, a semi-cylindrical single-sided plane convex to the viewer side, and a concentric magnifying Fresnel lens 12 formed on the opposite side and a frame 14 for holding a display and a Fresnel lens. Consists of. The viewer views the video from the flat side without the groove of the Fresnel lens. The lens shape (groove side) of the Fresnel lens is the display side. The original image is a 2D image, but by passing through the Fresnel lens, the shape and distance of the images reaching the left and right eyes appear different due to the effect of the semi-cylindrical curvature at the same time. Viewing the different images on the left and right makes it possible to view the images in 3D by utilizing the fact that the brain recognizes that the viewer is viewing a three-dimensional object or an image with perspective.

At this time, since the image reaching the left and right eyes can be separated by the Fresnel lens, a left / right separation device such as glasses is not necessary. Conventional images for creating two screens for left and right can be taken with two cameras with lenses that are 6 to 7 centimeters in width, which is the same as the width of a human eye, or 2D images can be created by computer processing. However, the image is over-exaggerated due to artificial processing. In addition, when processing perspective, it is difficult to process smoothly, and the depth is changed step by step, so the image is like a picture with many picture-story shows in a perspective direction rather than a solid (layered image). turn into. Therefore, it feels unnatural and feels “3D fatigue”, which is not suitable for long-time viewing. Since the device according to the present invention uses the natural recognition ability of the brain, the 3D image is natural and the three-dimensional effect and the sense of perspective can be felt smoothly, so there is little fatigue. In principle, there is no phenomenon in which the left and right images in the conventional glasses method or the naked eye method appear double (crosstalk). You do n’t need to wear glasses to watch it.

FIG. 2 is an example of a shape when the device of the present invention is not viewed or carried and when a touch panel is operated on a smartphone or tablet PC. The semi-cylindrical Fresnel lens 22 has a planar shape and is arranged in parallel with the display screen 21. Flat shape overall, not bulky

FIG. 3 shows another example of the shape when the device of the present invention is not viewed or carried and when the touch panel is operated on a smartphone or tablet PC. The semi-cylindrical Fresnel lens 32 has a planar shape and is arranged in parallel to the back surface of the display 31. The whole shape is flat and not bulky.

FIG. 4 is an explanatory diagram of the perspective method. A small symbol 41 or a large symbol 42 imitating a tree is arranged on a line extending radially from one point 43 on the screen. A line connecting the vertices of the symbol also gathers at point 43 (vanishing point). The picture and image drawn in perspective using the size and arrangement of such objects appear to be close to the point 44 and close to the point 43 in spite of the plane, and the trees look like tree-lined roads lined up on both sides of a straight road.

FIG. 5 is an explanatory diagram of stereoscopic effect due to parallax. When viewing the relatively close cube 52 with the left eye 51L and the right eye 51R, the L face of the cube 52 appears wider than the R plane to the left eye 51L and looks like a cube 53L. On the contrary, the right eye 51R looks like a cube 53R. Since the left and right eyes are originally viewed separately, the brain determines whether the objects being viewed are the same or different. If you forcibly lean or distant here, the cube 52 appears to be two. In the case of a cross-over, the left image appears as a cube 53L, and the right image appears as 53R. The reverse is true when viewing from a distance. The normal brain recognizes a cube as one object. Here, since different cubes can be seen between the left and right eyes, this cube is recognized as a solid rather than a plane, and the degree of the solid is recognized from the magnitude of the parallax. A close object is easy to obtain a three-dimensional effect because of its large parallax, but since the human eye has a width of 6 cm to 7 cm, a parallax is very small for a object that is several meters or more away, making it difficult to obtain a three-dimensional effect due to the parallax. This three-dimensional effect is different from the perspective described below, which means that the brain recognizes the shape as a three-dimensional image by looking at the different shape in the parallax when looking at an object.

FIG. 6 is an explanatory diagram of perspective by viewing angle (convergence angle). When viewing a point 64 at a distant distance m1, the viewing angle (convergence angle) θ1 decreases, and at the same time, the thickness of the lens 62L / R of the eye 61L / R becomes thin and the image of the point 64 is formed on the retina 63L / R. To do. The longest distance of m1 is when looking at almost infinity, such as stars, and θ1 approximates zero. Both straight lines forming θ1 of both eyes are almost parallel. Humans usually do not move their eyes more than parallel. When viewing a point 68 at a nearby distance m2, the viewing angle (convergence angle) θ2 increases, and at the same time, the thickness of the lens 66L / R of the eye 65L / R becomes thicker t2 and an image of the point 68 is formed on the retina 67L / R. To do. This minimum distance of m2 is called the distance of clear vision as the distance at which objects can be clearly seen, and is conventionally defined as 25 cm. The distance of clear vision is usually 25cm or more for those who are naked or who have corrected myopia with glasses. Here, the relationship among m1, m2, θ1, θ2, t1, and t2 is m1> m2, θ1 <θ2, and t1 <t2. This simultaneous relationship recognizes perspective. This is different from the perspective method described above, and does not depend on the size or shape of the object. Therefore, even a small object such as a point light source or a sphere whose direction is unknown can recognize the perspective.

As described above with respect to the three-dimensional effect, when the distance to the object is several meters or more, the three-dimensional effect is reduced due to the parallax, but the perspective can be recognized by the viewing angle and the movement of the crystalline lens in conjunction with the viewing angle. Many conventional 3D images use the difference in viewing angle (convergence angle). Shooting with two cameras or a twin-lens camera can shoot images with different viewing directions due to parallax, but it is unnatural if the angle (viewing angle) of the two cameras and lenses does not change depending on the distance of the object. However, the viewer's viewpoint is not always there. Therefore, twin-lens shooting in a scene with a plurality of objects is very difficult. Further, when the operation of t1 <t2 is performed, the brain can recognize that the point 68 is closer than the point 64 even with one eye. If this lens can be operated on a video display, it becomes an important element to feel the perspective.

FIG. 7 is an explanatory view of the light path of the image of the present invention as viewed from above. There is a semi-cylindrical magnifying Fresnel lens 72 disposed in front of the screen 71 of the video display, and the left eye 73L and the right eye 73R are viewed from a distance from the screen 71 more than a clear distance s. Here, the distance s of clear vision is conventionally defined as 25 cm, and the distance D1 between the left eye 73L and the right eye 73R is 6 cm to 7 cm for an adult and about 5 cm for a child. When the magnifying Fresnel lens is planar, the focal points are on both sides of the lens. A normal camera or magnifying glass has a single focal point where the focal point f0 is only one point on each surface, but the focal point of the semi-cylindrical magnifying Fresnel lens is a radius (r + f0) obtained by adding f0 to the curvature radius r. It exists on the circumference 74 of. Further, a focal point on the opposite surface exists on the circumference at a distance f0 passing from the circumference 72 on the straight line extending from the circumference 74 to the circumference 72 and passing through the point O. Since the position of the point O may change from the center to the end of the Fresnel lens, the portion expressed as a circumference may be an elliptical circumference.

In FIG. 7, the path from the point a0 will be described in the path of light at the center of the screen 71. The light emitted from the point a0 passes through the point a1L of the Fresnel lens surface 72 while being refracted and enlarged, and reaches the eye 73L on the straight line L1. The light emitted from the piece or point a0 passes through the point a1R of the Fresnel lens surface 72 while being refracted and enlarged, and reaches the eye 73R on the straight line R1. The left and right images are displayed so as to face the direction of each eye because they are refracted with the same magnification. When the image is facing the front, if you close one eye, both will be facing this. This is illustrated in FIG. The position of the magnified virtual image will be described using the path from the eyes. From left eye 73L, a straight line L1 passes through point a1L of Fresnel lens surface 72, and further extends as shown by a broken line to a point a2L, where an enlarged virtual image is formed. The eye lens performs focus adjustment at this point a2L. Similarly, the virtual image viewed from the right eye 73R is made at point a2R, and the focus is adjusted here. However, since a2L and a2R are separated by a distance δ between the left and right eyes, the image position seen by both eyes is the intersection point a3 on the extension line of the straight lines L1 and R1. This point a3 is behind the point a0 of the image on the display.

In FIG. 7, the width in which the image of the screen 71 is displayed is D2. The path from the left end point b0 and the right end point c0 in the light path at the left and right end portions of the image will be described. First, the light emitted from the left end point b0 passes through the point b1L of the Fresnel lens surface 72 while being refracted and enlarged, and reaches the eye 73L on the straight line L2. The light emitted from the point b0 passes through the point b1R on the Fresnel lens surface 72 while being refracted and enlarged, and reaches the eye 73R on the straight line R2. The magnification of each of the left and right images is slightly larger when the distance between the display and the Fresnel lens is farther, and the image is slightly distorted vertically as the incident angle to the Fresnel lens is shallower (oblique). Since the distance from the screen 71 to the Fresnel lens surface 72 is smaller than the image at the center point a0, the image enlargement rate is small and the incident angle is large, so the image distortion is large. This is illustrated in FIG. The position of the magnified virtual image will be described using the path from the eyes. From left eye 73L, a straight line L2 passes through point b1L of Fresnel lens surface 72, and further extends as shown by a broken line to a point b2L, where an enlarged virtual image is formed. The eye lens performs focus adjustment at this point b2L. Similarly, the virtual image viewed from the right eye 73R is made at point b2R, and the focus is adjusted here. The point b2L is slightly left and slightly in front of the point b2R. Since the points b2L and b2R are separated from each other, the image position seen by both eyes is an intersection b3 on the extension line of the straight line L2 and the straight line R2. This point b3 is behind and outside the point b0 of the image on the display. Similarly, the right end point c0 of the video on the display 71 is an intersection c3.

In FIG. 7, when the positions of the images that can be seen with both eyes are connected at each position of the image on the screen 71, a curve 76 connecting the points a3, b3, and c3 is obtained. In summary, the center of the screen has a higher magnification than both ends, and you can see the image in the back with both eyes. The focus position of the lens is also deeper toward the center.

The numerical range of the concrete example carried out is as follows.
<Size independent of screen (constant)>
D1: About 50 mm to 70 mm between eyes. Slightly different depending on children, adults, gender and nationality.
<Depends on screen size (variable)>
s: Distance of clear vision. Conventionally, it is 250mm or more at a distance where people can clearly see things. When D2 is 500 mm or more, D2 x about 2 or more is easy to see.
D2: Width dimension of display screen 71. About 70mm to about 150mm for typical smartphones and portable game consoles, about 100mm to about 250mm for tablet PCs, about 200mm to 350mm for PCs, about 70mm to 1500mm for TVs, the height is narrower than the width 4: 3 and 16: 9).
f0: Focal length of the Fresnel lens 72. D2x 1 to 10
t: Thickness of Fresnel lens 72. D2 / About 150 to about 400 and up to 2mm.
k1: Maximum distance between screen 71 and Fresnel lens 72. D2 / 1.5 ~ 10
k2: Minimum distance between screen 71 and Fresnel lens 72. k1x about 0.01 to about 0.9
r: radius of curvature of Fresnel lens 72. It may be a circle, but it may be an ellipse, a sphere, or an aspherical surface. D2x about 0.5 to about 10

This is one example of a typical smartphone. A natural 3D-looking structure can be realized.
D1: About 60mm between eyes
s: Distance for clear vision 250mm
D2: Screen width 75mm (height is 50mm)
f0: The focal length of the Fresnel lens. D2x1.7 = about 125mm
t: Thickness of Fresnel lens. D2 / 250 = 0.3mm.
k1: Maximum distance between screen and Fresnel lens. D2 / 2.5 = 30mm
k2: Minimum distance between the screen and the Fresnel lens. k1x0.3 = 9mm
r: radius of curvature. It may be a circle, but it may be an ellipse, a sphere, or an aspherical surface. D2x0.9 = Approx 70mm

If the screen width D2 is doubled, f0, t, k1, k2, and r can be considered to be about doubled. t is a maximum of 2 mm. When D2 is 500 mm or more, s is a distance that is easy to see when D2 × about 2 or more. However, adjustment is necessary to obtain a natural 3D feeling. The reason is that the interval between eyes is the only constant. Just because the screen is large doesn't mean you can widen your eyes. If you wear special glasses with the same effect as an exceptionally wide range, you can get a natural 3D feeling that does not depend on the size of the screen, but because the present invention is based on the concept of naked eyes, it corrects myopia and hyperopia. Don't think about wearing anything other than glasses or contact lenses. Therefore, since the distance between the eyes cannot be changed, it is necessary to adjust the dimensions to obtain a natural 3D feeling. This may be adjusted according to individual differences even with the same screen size. The radius of curvature r is the easiest to adjust.

Although the present invention can handle a large screen, a diagonal smartphone with a screen size of 3 to 7 inches (screen width of 50 mm to 150 mm) or a tablet PC with a screen size of up to 12 inches (screen width of about 250 mm) Mainly targeted at mobile computers. Conventional patented technology separates one screen into two screens and obtains a 3D image with a sense of depth (depth) due to the difference in the shift width between the two screens at the center and the left and right ends of the screen. . However, a volumetric stereoscopic effect has not been obtained.

This is because the screen divided into left and right is moving horizontally on the plane. In order to obtain a three-dimensional effect, it is necessary to have at least an angle even if the elements constituting the three-dimensional object are flat, as can be seen in “The Staring Dragon” (Non-Patent Document 3) which is a trick three-dimensional art. This depends on the magnitude of the incident angle to the normal from the eye that can be formed by the curvature of the Fresnel lens. The larger this angle is, the larger the angle at which the two plane images move in parallel and face each other. When this angle increases, the illusion that the brain is looking at a three-dimensional object is generated, and a 3D image with a sense of volume (three-dimensional effect) is obtained. A natural 3D feeling can be obtained only when both the perspective (depth) and the volume (three-dimensionality) coexist. Since the distance between the eyes is constant, this angle decreases as the screen width increases. Therefore, a natural 3D feeling can be obtained with a smaller screen. Ideally, if the distance between the eyes is about 60mm, the screen width is 180%, which is three times the width.

Increasing the curvature at the center of the screen to obtain a sense of volume on a large screen increases the distance between the screen and the lens at the center and increases the difference between both ends of the screen. The center will be enlarged. Therefore, there is no choice but to be satisfied with a 3D screen with a sense of depth on a large screen but a lack of volume. Experimentally, if the magnification ratio of the virtual image by the convex lens effect is less than about 1.1 times the center image relative to the images at both ends, a natural 3D feeling can be obtained. At both ends of the screen, the viewing distance s is short on a small screen, and the difference between the distance from the eye to the screen end and the angle can be relatively large. At both ends of the screen, the brain recognizes that the right and left eyes look differently in the magnification and distortion of the image, and that the stereoscopic view is viewed from different angles. Since the distance between the eyes does not change, the difference in the distance and angle from the left and right eyes to both ends of the screen is reduced on a large screen. Therefore, the volume feeling is also reduced. Ideally at both ends of the screen, if the distance between the eyes is about 60 mm, the screen width is three times that width, up to 180 mm.

FIG. 8 is an explanatory diagram of the principle of producing perspective in the present invention. The details described in FIG. 7 will be described with reference to FIG. 8. The virtual image of the central portion of the screen 81 can be formed on the curved surface 84L / R, and the interval δ between the virtual images seen by the left and right eyes 83L and 83R is larger in the vicinity of the center. The visible image looks farther from the left and right ends toward the center. Since most of the images have a distant view at the center, a natural perspective can be felt by a synergistic effect with the perspective method of FIG. The radius of the semi-cylindrical shape of the Fresnel lens is adjusted so that the magnification in the center increases but the perspective in the image does not reverse.

FIG. 9 is an explanatory diagram of the principle of producing a three-dimensional effect (volume feeling) near the center of an image in the present invention. The details described in FIG. 7 will be described with reference to FIG. 9. In the image of the central portion of the screen 91, the virtual image of the left eye 93L is on the surface 94L, and the virtual image of the right eye 93R is formed on the surface 94R. The two virtual images are separated by a distance δ. Further, the surface 94L faces the direction of the eyes 93L, and the surface 94R faces the direction of the eyes 93R. A perpendicular between the surface 94L and the surface 94R forms an angle θ. In this state, the brain cannot be recognized as a plane, but is recognized as a three-dimensional object in order to fit the eyelids. Whether a solid is a convex surface or a concave surface is determined by experience based on the object.

There is a three-dimensional paper craft of “Dragon staring” (Non-Patent Document 3), which is a remarkable example based on experience. When assembled, the body is a cuboid solid, but the head is a concave surface with the center recessed, and the eyes, nose and mouth are drawn there. From experience, people assume that their heads are three-dimensional and their faces are convex. If you rotate the dragon to the left or right while looking at the dragon, your body will rotate in that direction, but your face will appear to be waving as if you are looking at it. This is a phenomenon that occurs due to the fact that it is concave but is recognized as a convex surface (illusion). Returning to FIG. 9, even if the unevenness is not clear, the brain makes a judgment based on the object, so that an image 95 with a natural stereoscopic effect can be seen when viewed with both eyes. Although it has been described in FIG. 8 that the vicinity of the center looks far away, if there is a large object in the vicinity of the center that can be determined by the left and right parallax, the stereoscopic effect is prioritized by canceling out the synergistic effect of the expansion of the Fresnel lens.

When the image separated into the left and right is viewed with both eyes, the virtual image appears to be in a deep position. According to the present invention, a 3D trick art (Non-Patent Document 4) like “Dragon staring” (Non-Patent Document 3) such that the image near the center can be seen in front of the left and right eyes by making the curvature appropriate. It creates a sense of volume. The image near the left and right edges is distorted in a good sense by making the curvature appropriate in order to reproduce that when viewing a three-dimensional object, the left eye looks wide and the right eye looks wide on the right eye . This distortion has a difference between right and left, and the brain recognizes the image as a three-dimensional object.

FIG. 10 is an explanatory diagram of the principle of producing a stereoscopic effect (volume feeling) near both ends of an image according to the present invention. The details described with reference to FIG. 7 will be described with reference to FIG. 10. Of the images at the left and right end portions of the screen 101, the left-eye image 103L has a virtual image of the left eye 103L on the surface 104L1, and the right eye 103R has a virtual image slightly behind the surface 104L1. It can be 104R1. The virtual image 106L1 of the left eye 103L is to the left of the virtual image 106R1 of the right eye 103R by a distance δ, and the compression strain WL1 in the width direction of the virtual image of the left eye 103L is smaller than WR1 of the virtual image of 103r. When viewed with both eyes, an image is formed on the surface 105, and the left and right shapes are different, so the brain cannot be recognized as a flat surface, and is recognized as a three-dimensional object in order to fit the eyelids. Whether the solid is convex or concave is determined by experience based on the object, and a three-dimensional image 105L can be seen. Similarly, the image 105R can be seen at the right end.

FIG. 11 is a comprehensive explanatory diagram showing that a 2D image looks like a natural 3D image in the present invention. Most of the images are located near the center and the object you want to see the most is located at a short distance. In addition, the background is often distant from the center. These come from a natural screen structure. The present invention can feel the perspective and the stereoscopic effect most in the case of this screen configuration. Even moving images often pass the above configuration, so you can feel the perspective and stereoscopic effect with the impression at that time, and the brain remains perspective and stereoscopic even if the configuration changes I can see it. Unlike viewing conventional flat images with only the viewing angle of both eyes changed by parallax while keeping the focus of the lens constant, the viewing angle of both eyes and the focus adjustment of the lens are linked in the same way as when viewing normal scenery. There is almost no “3D tiredness” because I watch it. Unlike the conventional layered 3D, which is overly exaggerated and does not have a 3D effect (volume), the present invention uses the recognition power of the brain to recognize the original 3D image from the 2D image. Therefore, it is an epoch-making invention that can enjoy extremely natural 3D video without special equipment or glasses while maintaining normal 2D video.

The following types of Fresnel lens types and shapes are possible.
(1) -1-1 A rectangular convex Fresnel lens with a curved surface in the center of the screen or a curved surface in both the vertical and horizontal directions.
-2 A rectangular convex Fresnel lens with a curved surface in the center of the viewer that has a concave horizontal or vertical and horizontal curved surface.
-3 Planar shape with rectangular convex Fresnel lens
-2-1 A rectangular concave Fresnel lens with the viewer's center having a convex horizontal curved surface or both vertical and horizontal curved surfaces
-2 A rectangular concave Fresnel lens with a curved surface in the center of the viewer that has a concave horizontal or vertical and horizontal curved surface.
-3 flat shape with rectangular concave Fresnel lens
(2) Shape of the above-mentioned (1) saddle-shaped Fresnel lens
(3) Shape of the drum-shaped Fresnel lens of (1) above
(4) Shape obtained by continuously changing the thickness of the Fresnel lens in (1), (2) and (3) above in the lateral direction

The following variations can be considered for the configuration of the Fresnel lens.
(1) Configuration using one Fresnel lens.
(2) Configuration using two same or different Fresnel lenses
(3) Configuration using three same or different Fresnel lenses
(4) Configuration using multiple same or different Fresnel lenses

Embodiment 1 and FIG. 12 are embodiments using a single bowl-shaped Fresnel lens 122 having a relatively uniform thickness. Since the curved surface shape of the Fresnel lens changes depending on the size of the screen, it is necessary to adjust it to an ideal curved surface. As the simplest method, there is a method in which the shape is rigidly manufactured or a guide having a desired shape is installed around if it is flexible. This is easy, but it becomes bulky considering mobility.

The second method is a structure in which a flexible Fresnel lens is bent with a curvature close to a semi-cylindrical shape, so that there are grooves processed outside the both ends of the screen, and both ends of the Fresnel lens are fitted into the grooves. The grooves are angled to achieve the desired curvature. When operating the touch panel, when not viewing, when placing it in a bag or pocket, remove it from the groove and carry it with the Fresnel lens flat, or store a pocket part to store the removed Fresnel lens in the display unit. Alternatively, there is a method of removing the other side and making it flat with the screen while keeping one side attached. Some of the drawbacks are that the curvature is determined by the angle of the groove, so the part inserted into the groove is a mechanically fixed end, and the stress is higher than other parts of the Fresnel lens, and the risk of damage is high. can give.

As a third method, there is a method of cutting the Fresnel lens into a saddle shape or a drum shape in which the width in the vertical direction is changed between the center and both ends. Inserting into the groove is the same as the second method, but the curvature is small in the wide part and the curvature is large in the narrow part, so the cut was added to achieve the desired curvature. Since the inserted part is a mechanically free end, there is no concentration of stress. However, depending on the screen size, there may be a part that is partially large and wide, and it may be good for viewing but may be flat even if it is flat, resulting in poor mobility. In that case, as the fourth method, the part to be increased depending on the curvature is slightly thicker, and to decrease the curvature, if a thin Fresnel lens is prepared, the curvature can be changed in a rectangular shape without using a saddle shape or a drum shape. The insertion parts at both ends were also free ends and there was no stress concentration. The method can be selected depending on ease, freedom of adjustment, cost, etc.

Example 2 and FIG. 13 show an example in which a Fresnel lens is arranged on a curved surface portion of a kamaboko type whose one side is flat and the opposite side is semi-cylindrical.

Example 3 and FIG. 14 are examples in which a Fresnel lens is arranged on the curved surface portion of the concave lens shape opposite to the kamaboko type.

Example 4 and FIG. 15 are examples in which a plurality of Fresnel lenses are installed.

Example 5 and FIG. 16 are examples in which the display and the Fresnel lens are installed relatively inclined. There are cases where the top is far and the bottom is close and vice versa. Also, the upper and lower curvatures may be the same or different. Patent No. 3579683 (P3579683) “Manufacturing method of stereoscopic print, stereoscopic print” (Patent Document 7) specially corrects the printed matter for 3D and sees the photograph printed from the upper side with red and blue glasses. I'm stereoscopic. When viewed from diagonally above, the upper side of the photo is far and the lower side is closer, so it is characterized by adjusting the focus when the eyes follow up and down. In conventional 3D, the screen position is directly opposite (perpendicular) to the eyes, and focus adjustment was not performed, so the stereoscopic view was uncomfortable.

In addition, the perspective of the photograph is specially corrected for 3D. By tilting the photo, the top of the photo is narrow and the bottom is wide. Considering this perspective and different perspectives for the right and left eyes, it is characterized by a 3D impression that is corrected by soft image processing. The present invention also displays a natural 3D feeling by arranging the screen diagonally and increasing the focus adjustment amount of the eyes. The difference is that the perspective correction is performed by software image processing (pre-processing), whereas the present invention performs optical processing of the Fresnel lens using a circular or elliptical cone plane. Since it is an optical process, it can be done in real time. Further, by setting the center position of the Fresnel lens to an appropriate position, the prism diopter effect is effectively used to prevent unnecessary distortion of the image. If the center position is bad, the distortion on the lower side of the image may increase or the image may not appear dark. There are cases where two screens divided into left and right cannot be seen as one.

FIG. 17 is an explanatory view of the light path in the case of FIG. 16 in which the display and the Fresnel lens are relatively inclined and the vertical curvature is changed, as viewed from the side. The right figure is a cross section at the center of the screen, and the image of the upper part of the image on the screen 173 is refracted when passing through the Fresnel lens 172 from the path T1, and reaches the eye 171 through the path T2. Similarly, the lower part passes through the routes B3 and B2 and reaches the eye 171. The virtual image that can be seen by the eyes 171 can be formed on the surface 174 through T2 and T3 and B2 and B3 of the light path. The thickness t of the crystalline lens of the eye 171 becomes a distance s1 when the upper part is viewed, and thus becomes thicker as far as possible. When looking at the lower part, the distance is s2, so it gets thinner. Therefore, the lens is less likely to get tired because it is close to natural focus adjustment. Also, in Japanese Patent No. 3579683 (Patent Document 7), the screen 173 is tilted and the screen itself is trapezoidal for the front view of the left figure, so the image is corrected by software calculation processing, so the display in real time is It is difficult to animate. In the present invention, the upper and lower curvatures are smoothly changed by the Fresnel lens 172 having an appropriate focal length so that the perspective is optically corrected, and the visible image 176 appears to be viewed as normal. Since the present invention optically corrects, correction processing is possible in real time, so software processing is not necessary, and natural 3D images can be viewed with both photographs and videos.

FIG. 18 shows an example of dimensions in which the display device and the Fresnel lens are installed relatively inclined. The mounting width W21 to the upper frame of the Fresnel lens 182 is set wider than W1 with respect to the width W1 of the display screen 183. The mounting width W22 of the Fresnel lens 182 to the lower frame is set wider than W1. W21 is wider than W22. Since the Fresnel lens 182 has a curved surface shape, the mounting height H2 can be slightly smaller than H1. Since the screen is inclined with respect to the eyes, the screen height H1 is apparently low. Since the magnification and angle correction are performed by the prism opticer effect of the Fresnel lens 182, the center height H3 of the Fresnel lens is greater than the visible screen height and is larger than the screen height H1. The distance from the screen 183 to the Fresnel lens 182 is related to the curvature, and the upper distance D1 is larger than the lower distance D2. By cutting the outer shape of the Fresnel lens 182 in accordance with the image viewed with both eyes, an image without vertical wrinkles can be obtained, and the width when the Fresnel lens 182 is carried around can be minimized.

This is one of the actual dimensions of a typical smartphone. A more natural 3D structure can be realized because the movement of the crystalline lens is increased by tilting the screen.
W1 = 75, H1 = 50, W21 = 100, W22 = 85, H2 = 50, H3 = 65, D1 = 40, D2 = 15 (unit is mm)

With the autostereoscopic (3D) video apparatus and adapter of the present invention, a normal 2D display can be enjoyed as a pseudo 3D display. In addition, if the adapter of the present invention is attached to conventional video equipment such as a TV, a personal computer, and a tablet terminal, ordinary 2D video can be enjoyed as natural 3D video at low cost and easily. There is no need for expensive 3D-only video software, electronic equipment, 3D-compatible equipment, or glasses.

FIG.
11 Adapter 12 of the Present Invention Fresnel Lens 13 Image Display 14 Frame 2
21 Video display 22 Fresnel lens 23 Frame 3
31 Video display 32 Fresnel lens 33 Frame 4
41, 42 Row of trees 43 Vanishing point 44 Row of trees road 5
51L / R Eye 52 Three-dimensional Object 53L Image Visible with Left Eye 53R Image Visible with Right Eye
61L / R, 65L / R Eye 62L / R, 66L / R Lens 63L / R, 67L / R Retina 64 Far point 68 Near point m1, m2 Distance θ1, θ2 Angle of convergence t1, t2 Lens thickness FIG.
71 Image Display Screen 72 Fresnel Lens 74 Curved Fresnel Lens Linear Focal Position 73L / R Eye 75L / R Virtual Image Surface Visible with Left and Right Eyes 76 Image Surface Visible with Both Eyes t Fresnel Lens Thickness
L1, R1, L2, R2, L3, R3 Light path
a0, b0, c0 Display image
a1L / R, b1L / R, c1L / R Refraction point
a2L / R, b2L / R, c2L / R Virtual image
a3, b3, c3 Images visible with both eyes
k1, k2 Distance to Fresnel lens δ Distance between virtual image of left eye and right eye
r Curvature radius
f0 Focal length
s Distance to eyes
D1 Distance between eyes
D2 Video display screen width Figure 8
81 Image display screen 82 Fresnel lens 83L / R Eye 84L / R Virtual image surface 85 Image surface 86L / R viewed with both eyes Image position δL1 / 2/3, δR1 / 2/3 Left and right eyes Image interval seen in Figure 9
91 Image Display Screen 92 Fresnel Lens 93L / R Eyes 94L, R Position and Orientation of Virtual Image Visible with Left and Right Eyes δ Spacing Between Left and Right Virtual Images 95 Video Surface 96L / R Visible with Both Eyes Virtual Image θ Visible with Left and Right Eyes Left and Right Angle formed by the perpendicular of the virtual image of
101 Image Display Screen 102 Fresnel Lens 103L / R Eye 104L1 / R1 Position and Angle of Virtual Image Visible with Left and Right Eyes 105 Image Surface 105L / R Viewed with Both Eyes Image 106L / R, 107L / R Left and Right Left and Right Eyes The position and distortion of the virtual image seen by the eyes
wL1 / R1, wL2 / R2 Width of virtual image seen by left and right eyes δ Distance of virtual image seen by left and right eyes
111 Screen 112 of Video Display 112 Fresnel Lens 113L / R Eyes 12, 13, 14
121, 131, 141 Adapters 122, 132, 142 according to the present invention Fresnel lenses 123, 133, 143 Video display 124, 134, 144 Frame FIG.
151 Adapter 152, 155, 156 according to the present invention Fresnel lens 153 Video display 154 Frame FIG.
161 Adapter 162 of the present invention Fresnel lens 163 Video display 164 Frame FIG.
171 Eye 172, 175 Video display screen 173 Virtual image plane 174, 176 Video plane t seen by both eyes t Thickness of the crystalline lens
T1, T2, T3, B1, B2, B3 Light path
s1, s2 Distance to the visible image Figure 18
181 Adapter 182 of the present invention Fresnel lens 183 Video display 184 Frame
W1, H1 screen dimensions
W21, W22, H2 Fresnel lens mounting dimensions
H3 Fresnel lens center width
Distance between D1 and D2 screen and Fresnel lens

Claims (11)

An autostereoscopic (3D) video apparatus characterized by creating a left-right parallax in a plane image and making it appear as a stereoscopic image with the naked eye, and an image apparatus characterized in that a Fresnel lens is arranged on a curved surface. The autostereoscopic (3D) video apparatus and adapter according to claim 1, wherein the Fresnel lens is arranged in a semi-cylindrical shape, a semi-elliptical cylindrical shape, a spherical shape, and an aspherical shape. The autostereoscopic (3D) video apparatus according to claim 2, wherein a single Fresnel lens is disposed in the autostereoscopic (3D) video apparatus and adapter according to claim 1. The autostereoscopic (3D) video apparatus according to claim 2, wherein a plurality of Fresnel lenses are arranged in the autostereoscopic (3D) video apparatus and adapter according to claim 1. The autostereoscopic (3D) video apparatus and adapter according to claim 1, wherein the Fresnel lens used in the 3D adapter is flexible. In the above-mentioned autostereoscopic (3D) video apparatus and adapter, the 3D adapter is a flexible Fresnel lens, and when viewed, the Fresnel lens has a semi-cylindrical curved surface, and has a frame that can be flat when not viewed or carried. 6. An autostereoscopic (3D) video apparatus and a stereoscopic image apparatus according to claim 5, 7. The adapter according to claim 1, wherein the thickness of the Fresnel lens sheet is 0.8 mm or less, and the autostereoscopic (3D) video apparatus and adapter. 3D adapter characterized in that the above-mentioned naked eye 3D adapter has a curved surface when viewed, and can be stored on the back of the main unit when operating a touch panel such as a tablet terminal or a smartphone or when carrying it when not viewing. In the above-mentioned naked eye 3D adapter, the ratio between the length of the long axis of the video screen and the thickness of the Fresnel lens is the length of the long axis: the thickness of the Fresnel lens = 100: 1 or more. In the above-mentioned naked eye 3D adapter, the screen of the video equipment is arranged obliquely in a direction away from the viewer, and the upper part, which is the far side of the screen, is arranged with an inclination to improve the perspective of being reduced more than the lower part. 3D adapter featuring a Fresnel lens with an open cone or elliptical cone shape. A 3D adapter characterized in that the shape of the autostereoscopic 3D adapter in a flat state is rectangular, saddle-shaped, drum-shaped or fan-shaped.