TW202107158A - Virtual reality optical device with two focusing planes - Google Patents

Abstract

A virtual reality (VR) optical apparatus having two focusing planes is provided. The VR optical apparatus includes a display panel, and a first lens, a second lens, a quarter-wave plate, and a reflective polarizer that are sequentially arranged. The display panel is configured to emit first light having a first polarization and second light having a second polarization. The first lens includes a first surface and a second surface. The second surface is close to the display panel, and the first surface is close to the second lens, and the first surface is a transmissive-reflective surface. The reflective polarizer is configured to allow light having P polarization to pass through.

Description

Virtual reality optical device with dual focus planes

The present invention relates to an optical system, in particular to a virtual reality (VR) optical device with dual focus planes.

Stereoscopic image displays, such as virtual reality (VR) display devices, generally project left-eye and right-eye images with different viewing angles to the left and right eyes of the user, and the left and right eyes of the user are respectively Focus on different planes to produce stereo vision.

Although this kind of stereo vision allows users to perceive a stereo scene, the human eyes still focus on different planes at the same depth. Compared with the human eyes observing objects in the actual three-dimensional space, the stereo vision produced by the stereo image display It is different from the visual effect actually felt by the human eye. For example, when the human eye is viewing an object in the actual three-dimensional space, the focus position and imaging position 110 of the left eye and the right eye are the same, and the image near the imaging position 110 is clear, but on the left and right sides of the human eye The viewing angle of the picture is more blurred, but the visual distance and the focus distance are equal, as shown in Figure 1A.

However, the image projected by the 3D image display is clear in each viewing angle range, and the imaging position 140 of the image object felt by the user is behind the display panel 150 of the 3D image display, as shown in FIG. 1B. However, the visual distance and the focusing distance are not the same, and this visual difference may also cause dizziness for some users. This effect is called the vergence-accommodation conflict (VAC). In addition, the human eye can select the focus range when viewing objects in the actual scene, but the existing stereoscopic image display does not have this function, which causes a poor user experience.

The present invention provides a virtual reality optical device with dual focus planes to solve the above-mentioned problems. The aforementioned virtual reality optical device includes: a display panel, and a first lens, a second lens, a quarter wave plate, and a polarizing mirror arranged in sequence. The display panel is used to emit a first light with a first polarization and a second light with a second polarization. The first lens includes a first surface and a second surface. The second surface is close to the display panel, the first surface is close to the second lens, and the first surface is a semi-transmissive mirror surface. The polarizing mirror is used to let light with P polarization pass through.

In the above embodiment, the first polarization is R polarization and the second polarization is L polarization. The first light emitted by the display panel sequentially passes through the first lens, the second lens, the quarter wave plate and the polarizing mirror to form a first image in the eyes of a user. The second light emitted by the display panel passes through the first lens, the second lens, and the quarter wave plate in sequence, and the second light having the second polarization is transmitted by the quarter wave The plate is converted to S polarization. The second light with S polarization is reflected by the polarizing mirror, and is converted into R polarization through the quarter wave plate, and the second light with R polarization passes through the second lens and is The first surface of the first lens reflects. The second light reflected by the first surface passes through the second lens and the quarter wave plate to be converted into P polarization, and the second light with P polarization passes through the polarizing mirror and is The user's eyes form a second image.

In the above embodiment, the first image formed by the first light on the user’s eyes has a first image distance, and the second image formed by the second light on the user’s eyes has a second image distance, The second image distance is greater than the first image distance.

In some embodiments, the first polarization is P polarization and the second polarization is S polarization, and the virtual reality optical device further includes a half-wave plate disposed between the first lens and the display panel. The first light emitted by the display panel sequentially passes through the half-wave plate, the first lens, the second lens, the quarter-wave plate, and the polarizing mirror to form a first image in the eyes of the user.

In the above embodiment, the second light with S polarization is converted to L polarization after passing through the half-wave plate, and the second light with L polarization passes through the first lens, the second lens, and the quarter wave in sequence. The second light with L polarization is converted into S polarization by the quarter wave plate. The second light with S polarization is reflected by the polarizing mirror, and is converted into R polarization after passing through the quarter-wave plate, and the second light with R polarization passes through the second lens and is passed through the second lens of the first lens. A surface reflection. The second light reflected by the first surface passes through the second lens and the quarter wave plate to be converted into P polarization, and the second light with P polarization passes through the polarizing reflector and forms in the eyes of the user The second image.

In the above embodiment, the first image formed by the first light on the user's eyes has a first image distance, and the second image formed by the second light on the user's eyes has a second image distance, wherein The second image distance is greater than the first image distance.

In some embodiments, the display panel emits the first light and the second light at the same time. In other embodiments, the display panel uses time division multiplexing to emit the first light and the second light in turn.

In some embodiments, the first lens may be a lens group composed of multiple optical lenses.

In some embodiments, the first surface of the first lens can be independent of the first lens, and can be realized by a separate semi-transmissive and semi-reflective lens.

In some embodiments, the second lens may be a lens group composed of multiple optical lenses.

The following description is a preferred implementation of the invention, and its purpose is to describe the basic spirit of the invention, but is not intended to limit the invention. The actual content of the invention must refer to the scope of the claims that follow.

It must be understood that the words "including", "including" and other words used in this specification are used to indicate the existence of specific technical features, values, method steps, operations, elements, and/or components, but they do not exclude Add more technical features, values, method steps, job processing, components, components, or any combination of the above.

Words such as "first", "second", and "third" used in the claims are used to modify the elements in the claims, and are not used to indicate that there is an order of priority, antecedent relationship, or an element Prior to another element, or the chronological order of execution of method steps, is only used to distinguish elements with the same name.

FIG. 2A is a schematic diagram showing a virtual reality optical device according to an embodiment of the present invention. In one embodiment, the virtual reality optical device 200 includes a display panel 210, a lens 212, a lens 214, a quarter-wave plate 216, and a polarizing mirror 218, wherein the virtual reality optical device 200 The elements 212-218 can be regarded as a stacked optical lens structure arranged in sequence, and can be arranged in an optical component.

The display panel 210 can be, for example, a liquid crystal panel, a light-emitting diode panel, an organic light-emitting diode panel, liquid crystal on silicon , LCoS) panel, or micro light emitting diode (Micro LED) panel, but the present invention is not limited to this.

The display panel 210 can emit, for example, light with R polarization and light with L polarization, which respectively represent images at different distances, such as a distant image and a near image. Wherein, the display panel 210 can output light with R polarization and light with L polarization at the same time, or switch between the light with R polarization and the light with L polarization by means of time multiplexing.

The lens 214 may be, for example, a general optical lens. The lens 212 is, for example, a special lens, where the surface 2121 (for example, the first surface) of the lens 212 close to the lens 213 is, for example, a half-transmitting semi-reflective mirror surface (for example, it can be realized by a special coating), and the lens 213 is close to the surface 2122 of the display panel 210 ( For example, the second surface) is, for example, a normal lens surface. The reflectance/transmittance of the surface 2121 can be expressed as 50R/50T, for example, which means that 50% of the light from the left side of the surface 2121 will be reflected by the surface 2121, and 50% of the light will pass through the surface 2121. In addition, the surfaces 2121 and 2122 of the lens 212 can be matched with different types of surfaces. For example, the surfaces 2121 and 2122 can be flat-convex, concave-convex, convex-flat, or convex-concave surfaces, respectively, but the invention does not Limited to this.

In some embodiments, the lens 212 may be a lens group composed of multiple optical lenses, and all lens surfaces in the lens group may be concave, convex, aspherical, free-form surface, and Fresnel lens (Fersnel lens). ).

In addition, the semi-transmissive and semi-reflective mirror of the surface 2121 of the lens 212 can be independently derived from the first lens, and can be realized by a separate semi-transmissive and semi-reflective lens.

In some embodiments, the lens 214 may be a lens group composed of multiple optical lenses, and all lens surfaces in the lens group may be concave, convex, aspherical, free-form surface, and Fresnel lenses.

The quarter wave plate 216 can also be called a phase retarder, which is used to retard the phase of the incident light by 90 degrees. Whether it is incident light from the right side surface or the left side surface of the quarter wave plate 216, after passing through the quarter wave plate 216, its phase will be delayed by 90 degrees.

The polarizing mirror 218 is used to allow a light with a specific polarization to pass through, for example, a light with a P polarization.

FIG. 2B is a schematic diagram of the traveling path of R-polarized light according to an embodiment of the present invention. FIG. 2C is a schematic diagram of the traveling path of L-polarized light according to an embodiment of the present invention.

In an embodiment, the R-polarized light emitted by the display panel 210 represents a near image, and the L-polarized light represents a distant image. The R-polarized light output from the display panel 210 may directly pass through the lenses 212 and 214, and be converted into P-polarized light after passing through the quarter-wave plate 216. If the polarizing reflector 218 is designed to pass P-polarized light, the P-polarized light generated after conversion by the quarter-wave plate 216 can pass through the polarizing reflector 218 and enter the user's eye 220, and is in the user's eye 220 produces a virtual image with a shorter image distance. The image distance of the virtual image is, for example, 295 millimeters (mm), and the position where the user's eyes 220 observe the virtual image is behind the display panel 210, as shown in FIG. 3A.

The imaging path of the R-polarized light emitted by the display panel 210 in the eyes of the user 220 can be referred to, for example, Figure 2B, where the light paths 305, 306, and 307 represent the emission at different positions 301, 302, and 303 in the display panel 210. The travel path of the outgoing R-polarized light. The R-polarized light emitted from different positions 301, 302, and 303 of the display panel 210 can directly pass through the lenses 212 and 214, the quarter wave plate 216 (converted to P-polarized light), and the polarizing mirror 218 (allowing P-polarized light passes through), and a virtual image with a shorter image distance is generated in the user's eye 220.

In addition, the L-polarized light output from the display panel 210 can directly pass through the lenses 212 and 214, and pass through the quarter-wave plate 216 before being converted into S-polarized light. Because the polarizing mirror 218 is designed to pass P-polarized light, the S-polarized light generated after conversion by the quarter-wave plate 216 will be reflected by the polarizing mirror 218, and the reflected S-polarized light will pass through a quarter. A wave plate 216 is converted into R polarized light and passes through the lens 214. However, a part (about 50%) of the above-mentioned R-polarized light will be reflected by the side surface 2121 of the lens 212. The reflected R-polarized light passes through the lens 214 and the quarter wave plate 216 again, and then is converted into P-polarized light. At this time, the P-polarized light generated after the conversion can enter the user's eye 220 through the polarizing mirror 218, and produce a virtual image with a longer image distance in the user's eye 220, as shown in FIG. 2C. The image distance of the above virtual image has undergone multiple refractions, so the converted image distance in Figure 2C is, for example, 1726 millimeters (mm), which is longer than the image distance in Figure 2B. The user’s eyes 220 observe the above The virtual image is formed behind the display panel 210, as shown in FIG. 3B.

The imaging path of the L-polarized light emitted by the display panel 210 in the eyes of the user 220 can be referred to, for example, Figure 2C, where the light paths 315, 316, and 317 indicate that the light paths 315, 316, and 317 are emitted at different positions 311, 312, and 313 in the display panel 210. The travel path of the L polarized light out. After the L-polarized light passes through the lenses 212 and 214 and the quarter wave plate 216 directly, it is converted into S-polarized light and is reflected by the polarizing mirror 218 (allowing P-polarized light to pass through). The reflected S-polarized light After passing through the quarter wave plate 216, it will be converted into R-polarized light and pass through the lens 214, and be reflected by the side surface 2121 of the lens 212. The reflected R-polarized light passes through the lens 214 and the quarter-wave plate 216 again, and then is converted into P-polarized light, and a virtual image with a shorter image distance is generated in the user's eye 220.

In simple terms, the 3A and 3B images can be drawn together as the 3C image according to the actual ratio of the image distance, which means that the user's eyes 220 can receive images of different image distances from the display panel 210 at the same time, and the user's eyes 220 The focus point can be adjusted to align the image with a longer image distance (for example, 1726mm) or an image with a shorter image distance (for example, 295mm), but the invention is not limited to this.

It should be noted that the different image distances used in Figures 2 to 3 of this case are for illustrative purposes only, and those with ordinary knowledge in the field of the present invention can adjust the lens in the virtual reality optical device 200 according to actual conditions. Configure and focus to obtain images with longer image distances and images with shorter image distances.

FIG. 4A is a schematic diagram of a virtual reality optical device according to another embodiment of the present invention.

As shown in Figure 4A, the virtual reality optical device 400 is similar to the virtual reality optical device 200 in Figure 2A. The difference is that the display panel 410 in the virtual reality optical device 400 can simultaneously emit P-polarized light. And S-polarized light, and the virtual reality optical device 400 is further equipped with a half-wave plate 411 between the display panel 410 and the lens 412.

In detail, the display panel 410 and the half-wave plate 411 in the virtual reality optical device 400 are different from the virtual reality optical device 200. Because the polarizing refractor 418 also allows P-polarized light to pass through, if the half-wave plate 411 is not provided between the display panel 410 and the lens 412, the P-polarized light and S-polarized light emitted by the display panel 410 pass through a quarter. The polarized light generated by the first conversion and the third conversion of the wave plate 416 is not P-polarized light, so it cannot pass through the polarizing mirror 418 and present images with different image distances in the user's eyes 420. When the half-wave plate 411 is arranged between the display panel 410 and the lens 412, the P-polarized light and S-polarized light emitted by the display panel 410 are converted into R-polarized light by the half-wave plate 411 before entering the lens 412. Therefore, the light paths of the R-polarized light and the L-polarized light after entering the lens 412 are similar to those in FIG. 2B and FIG. 2C, respectively, so the details will not be repeated here.

FIG. 4B is a schematic diagram of a virtual reality optical device according to another embodiment of the present invention.

In some embodiments, the virtual reality optical device 400 may include display panels 410A and 410B, and a polarization beam splitter 424. Among them, the display panels 410A and 410B are used to respectively emit P-polarized and S-polarized light, and the P-polarized light and S-polarized light can be synthesized by a polarizing beam splitter (PBS) 424, and then enter the half-wave plate 411. And lens 412, as shown in Figure 4B. When the half-wave plate 411 is arranged between the display panel 410 and the lens 412, the P-polarized light and S-polarized light emitted by the display panel 410 are converted into R-polarized light by the half-wave plate 411 before entering the lens 412. Therefore, the light paths of the R-polarized light and the L-polarized light after entering the lens 412 are similar to those in FIG. 2B and FIG. 2C, respectively, so the details will not be repeated here.

FIG. 5A is a schematic diagram of a virtual reality device according to an embodiment of the invention.

The virtual reality optical devices 200 and 400 shown in Figure 2A or Figures 4A-4B, for example, can be set in a head-mounted display (HMD) 500, so that the head-mounted display can be worn Users can watch Virtual Reality (VR).

As shown in FIG. 5A, the head-mounted display 500 includes two sets of virtual reality virtual reality optical devices 500-1 and 500-2, a transmission interface 540, and a display controller 550. In some embodiments, the virtual reality optical devices 510-1 and 510-2 can be implemented by the virtual reality optical device 200 in FIG. 2A. In some embodiments, the virtual reality optical devices 510-1 and 510-2 can be implemented by the virtual reality optical device 400 in FIG. 4.

For example, in order to present 3D vision in virtual reality, the two sets of virtual reality optical devices 500-1 and 500-2 configured in the head-mounted display 400 can be arranged on the head-mounted display 500 in a predetermined manner, for example. In the outer shell 530 of, and used for left eye and right eye imaging respectively. The housing 530 may include a strap or other auxiliary device (not shown) for the user to wear on the head to view the screen through the head-mounted display 500. In the embodiment of FIG. 5A, the display panels 510-1 and 510-2 in the virtual reality optical devices 500-1 and 500-2 are, for example, independent display panels, and there is an angle difference between the two.

FIG. 5B is a schematic diagram of a virtual reality device according to another embodiment of the present invention. In another embodiment, the display panels 510-1 and 510-2 in the virtual reality optical devices 500-1 and 500-2 are side by side and parallel, and there is no angle difference between the two, as shown in Fig. 5B Show. In other embodiments, the display panels 510-1 and 510-2 in the virtual reality optical devices 500-1 and 500-2 can be implemented by the same display panel, for example.

Regardless of whether the head mounted display 500 is implemented by the configuration shown in Figure 5A or Figure 5B, the paths of the R polarized light and L polarized light displayed by the virtual reality optical devices 500-1 and 500-2 are similar to those shown in the first Figures 2B to 2C, so the details will not be repeated here.

The display controller 550 is used to control the display screens on the display panel 510-1 and the display panel 510-2. For example, the display controller 550 can be a general-purpose processor (general-purpose processor), a digital signal processor (DSP), an image signal processor (ISP) or a circuit with equivalent functions, which can be accessed from the transmission interface 540 A host receives image data, including, for example, left-eye images and right-eye images, and the display controller 550 transmits the received left-eye images and right-eye images on the virtual reality optical devices 500-1 and 500-2, respectively Display, so that users can watch a three-dimensional virtual reality scene. In addition, because of the special design of the virtual reality optical devices 500-1 and 500-2 of the present invention, the user's eyes can simultaneously receive two virtual reality scenes with different image distances, and the user's eyes can focus on their own Choose to view the 3D images in image planes with different image distances.

The transmission interface 540 is used to receive image data (for example, including left-eye images and right-eye images, such as RGB images) from a host, and transmit the image data on the display panel 510-1 and through the display controller 550. The display panel 510-2 performs playback. For example, the transmission interface 540 can be a High Definition Multimedia Interface (HDMI) or a DisplayPort (DP) interface, but the invention is not limited to this.

Although the present invention is disclosed as above in a preferred embodiment, it is not intended to limit the scope of the present invention. Anyone with ordinary knowledge in the technical field can make some changes and modifications without departing from the spirit and scope of the present invention. Retouching, therefore, the scope of protection of the present invention shall be subject to the scope of the attached patent application.

110, 140: imaging position 150: display panel 200, 400, 500-1, 500-2: virtual reality optical device 210, 410, 510-1, 510-2: display panel 212, 412, 512-1, 512-2: lens 214, 414, 514-1, 514-2: lens 216, 416, 516-1, 516-2: quarter wave plate 218, 418, 518-1, 518-2: Polarizing mirror 220, 420: user's eyes 2121, 2122: surface 301-303, 311-313: location 305-307, 315-317: light path 410A, 410B: display panel 411: Half Wave Plate 500: Head-mounted display 530: Shell 540: Transmission interface 550: display controller

Figure 1A is a schematic diagram of an object in a three-dimensional space being imaged by the human eye. Figure 1B is a schematic diagram of an object displayed by a stereoscopic image display being imaged by the human eye. FIG. 2A is a schematic diagram showing a virtual reality optical device according to an embodiment of the present invention. FIG. 2B is a schematic diagram of the traveling path of R-polarized light according to an embodiment of the present invention. FIG. 2C is a schematic diagram of the traveling path of L-polarized light according to an embodiment of the present invention. FIG. 3A is a schematic diagram of the image distance of R polarized light in the embodiment of FIG. 2A of the present invention. FIG. 3B is a schematic diagram of the image distance of L polarized light in the embodiment of FIG. 2A of the present invention. Fig. 3C is a schematic diagram of the actual image distance in the embodiment according to Figs. 3A-3B. FIG. 4A is a schematic diagram showing a virtual reality optical device according to another embodiment of the present invention. FIG. 4B is a schematic diagram of a virtual reality optical device according to another embodiment of the present invention. FIG. 5A is a schematic diagram of a virtual reality device according to an embodiment of the invention. FIG. 5B is a schematic diagram of a virtual reality device according to another embodiment of the present invention.

200: Virtual reality optical device

210: display panel

212: lens

214: lens

216: quarter wave plate

218: Polarizing mirror

220: User's eyes

2121, 2122: surface

Claims (10)

A virtual reality optical device with dual focus planes, comprising: a display panel, and a first lens, a second lens, a quarter wave plate, and a polarizing mirror arranged in sequence, Wherein, the display panel is used to emit a first light with a first polarization and a second light with a second polarization, The first lens includes a first surface and a second surface, the second surface is close to the display panel, the first surface is close to the second lens, and the first surface is a semi-transmissive mirror surface, The polarizing mirror is used to allow light with P polarization to pass through. The virtual reality optical device with dual focus planes as described in item 1 of the scope of patent application, wherein the first polarization is R polarization and the second polarization is L polarization, Wherein, the first light emitted by the display panel sequentially passes through the first lens, the second lens, the quarter wave plate, and the polarizing reflector to form a user’s eye. An image. The virtual reality optical device with dual focus planes as described in item 2 of the scope of patent application, wherein the second light rays sequentially pass through the first lens, the second lens, and the quarter wave plate, and The second light with the second polarization is converted into S polarization by the quarter wave plate, Wherein, the second light with S polarization is reflected by the polarizing mirror, and is converted into R polarization by passing through the quarter wave plate, and the second light with R polarization passes through the second lens, And reflected by the first surface of the first lens, Wherein, the second light reflected by the first surface passes through the second lens and the quarter wave plate to be converted into P polarization, and the second light with P polarization passes through the polarizing mirror, And a second image is formed in the eyes of the user. The virtual reality optical device with dual focus planes as described in item 3 of the scope of patent application, wherein the first image formed by the first ray of the user’s eyes has a first image distance, and the second ray The second image formed by the user's eyes has a second image distance, wherein the second image distance is greater than the first image distance. The virtual reality optical device with dual focus planes as described in the first item of the scope of patent application, wherein the first polarization is P polarization and the second polarization is S polarization. As described in item 5 of the scope of patent application, the virtual reality optical device with dual focus planes further includes a half wave plate arranged between the first lens and the display panel, Wherein, the first light emitted by the display panel passes through the half-wave plate, the first lens, the second lens, the quarter-wave plate and the polarizing mirror in order to a user The eyes proceed to form a first image. The virtual reality optical device with dual focus planes as described in item 6 of the scope of patent application, wherein the second light with S polarization is converted into L polarization after passing through the half-wave plate, and the second light with L polarization is Two rays of light pass through the first lens, the second lens, and the quarter wave plate in sequence, and the second light with L polarization is converted into S polarization by the quarter wave plate, Wherein, the second light with S polarization is reflected by the polarizing mirror, and is converted into R polarization by passing through the quarter wave plate, and the second light with R polarization passes through the second lens, And reflected by the first surface of the first lens, Wherein, the second light reflected by the first surface passes through the second lens and the quarter wave plate to be converted into P polarization, and the second light with P polarization passes through the polarizing mirror, And a second image is formed in the eyes of the user. The virtual reality optical device with dual focus planes as described in item 7 of the scope of patent application, wherein the first image formed by the first light in the eyes of the user has a first image distance, and the second The second image formed by the light in the eyes of the user has a second image distance, wherein the second image distance is greater than the first image distance. In the virtual reality optical device with dual focus planes as described in item 1 of the scope of patent application, the display panel emits the first light and the second light at the same time. In the virtual reality optical device with dual focus planes as described in claim 1, wherein the display panel uses time multiplexing to emit the first light and the second light in turn.

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