A foldable optical waveguide near-eye display device

Abstract

The present invention discloses a foldable optical waveguide near-eye display device, comprising: an image source (111), a prism (121) with a cylindrical surface, a curved lens (131), a prism (141), and a prism group (151) composed of two or more prisms glued together in sequence, wherein a prism face of the prism (121) is partially or entirely a cylindrical surface, and the cylindrical surface faces the image source (111); the prism (121) is connected to the prism (141) via a prism face other than the cylindrical surface to form a first glued surface; the prism (121) is connected to the surface opposite to the curved surface of the curved lens (131) via another prism face other than the cylindrical surface to form a second glued surface; the prism (141) and each prism of the prism group (151) are glued together in sequence.

Description

Technical Field

[0001] The present invention relates to an optical waveguide near-eye display device, and in particular to a foldable optical waveguide near-eye display device. Background Art

[0002] At present, the existing optical machine technologies of optical waveguide near-eye display devices mostly adopt the technical solutions of lens imaging and adding multi-layer coated small-angle array reflective lenses.

[0003] However, this technical solution has the following disadvantages:

[0004] 1. The imaging part of the lens is too large, which makes it impossible to reduce the size of the entire near-eye display device and makes it too heavy;

[0005] 2. The field of view is small, with the maximum vertical field of view less than 25 degrees and the maximum horizontal field of view less than 40 degrees;

[0006] 3. The reflected light of the array sheets after the first reflective array sheet must penetrate the previous array reflective film at least 3 times, which will cause serious brightness attenuation;

[0007] 4. It needs to go through multiple layers of coating, the coating process is complicated, the yield is not high, and the light and dark stripes of the reflected image cannot be completely improved;

[0008] 5. To achieve a horizontal field of view angle close to 40 degrees, high-refractive-index optical glass is required, but optical plastic resin cannot currently achieve high refractive index and high optical performance. Summary of the invention

[0009] In order to overcome the above-mentioned deficiencies in the prior art, one of the purposes of the present invention is to provide a foldable optical waveguide near-eye display device, which greatly reduces the volume of the near-eye display device by adopting a prism plus curved surface reflection method.

[0010] Another object of the present invention is to provide a foldable optical waveguide near-eye display device, which can increase the vertical field of view angle from less than 25 degrees to more than 36 degrees by adopting a cylindrical lens plus a prism plus a curved surface transmission reflective imaging method, and by adopting the left and right image sources to transmit partial images to form a complete large field of view angle image in the human eye, the horizontal field of view angle can be increased from less than 40 degrees to more than 55 degrees.

[0011] Another object of the present invention is to provide a foldable optical waveguide near-eye display device. By adopting a reflective lens with a horizontal deflection angle greater than or equal to 30 degrees, the reflected light from the array sheet after the first reflective array sheet only needs to pass through the array reflective film before it once, thereby greatly reducing the brightness attenuation.

[0012] Another object of the present invention is to provide a foldable optical waveguide near-eye display device. By increasing the angle of the reflective lens, any imaging light of the image to be displayed is reflected or transmitted at most once on each array reflective lens, which can greatly reduce the number of coating layers of the array reflective lens, improve the yield, and ensure the purity and uniformity of the reflected image on each array reflective lens, providing users with high-quality image enjoyment.

[0013] To achieve the above-mentioned purpose, the present invention provides a foldable optical waveguide near-eye display device, comprising: an image source (111), a prism (121) with a cylindrical surface, a curved lens (131), a prism (141), and a prism group (151) composed of two or more prisms glued together in sequence, wherein a prism face of the prism (121) is partially or entirely a cylindrical surface, and the cylindrical surface faces the image source (111); the prism (121) is connected to the prism (141) via a prism face other than the cylindrical surface to form a first glued surface; the prism (121) is connected to the surface opposite to the curved surface of the curved lens (131) via another prism face other than the cylindrical surface to form a second glued surface; the prism (141) and each prism of the prism group (151) are glued together in sequence.

[0014] Preferably, the concave surface of the cylinder faces the image source (111).

[0015] Preferably, the radius of curvature of the cylindrical surface is less than 40 mm.

[0016] Preferably, the angles formed by the first gluing surface and the axial direction of the cylindrical surface and the second gluing surface are both between 35 and 55 degrees.

[0017] Preferably, the first bonding surface is coated with a partially transmissive and partially reflective film or a reflective polarizing film.

[0018] Preferably, if the first bonding surface is coated with a reflective polarizing film, a quarter phase delay film is additionally coated on the second bonding surface.

[0019] Preferably, the curved surface of the curved lens (131) is coated with an inwardly directed high-reflection film.

[0020] Preferably, the bonding surfaces of the array bonding surface group formed by sequentially bonding the prisms (141) and the prisms of the prism group (151) are parallel to each other, and the angle between the bonding surfaces and the lower surface is greater than 30 degrees.

[0021] Preferably, the array bonding surface is coated with a partially transmissive and partially reflective film.

[0022] Preferably, the prism (141) is synthesized by gluing a trapezoidal prism and a quadrangular prism whose facets are not perpendicular to each other; a side surface between two bottom surfaces of the trapezoidal prism is glued to the first prism of the prism group (151); another side surface opposite to the side surface is glued to the facet of the quadrangular prism whose facets are not perpendicular to each other relative to the first gluing surface to form a third gluing surface; after gluing, at least one facet of the quadrangular prism whose facets are not perpendicular to each other is on the same plane as a bottom surface of the trapezoidal prism.

[0023] Compared with the prior art, the foldable optical waveguide near-eye display device of the present invention effectively shortens the optical path space by using a prism plus a curved lens for multiple refractions and reflections, thereby achieving the purpose of reducing the volume and weight of the device. The vertical and horizontal field of view angles are greatly increased by using a cylindrical lens in front of the image source and combining the left and right conductive parts of the picture into a complete high-quality picture with a large horizontal field of view. The present invention also uses an array reflective film with a horizontal tilt angle greater than 30 degrees, which reduces the attenuation of brightness, improves the uniformity of the picture, simplifies the coating process, and improves the yield of the product. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic structural diagram of a foldable optical waveguide near-eye display device of the present invention. DETAILED DESCRIPTION

[0025] The following describes the implementation of the present invention through specific examples and in conjunction with the accompanying drawings. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific examples, and the details in this specification can also be modified and changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention.

[0026] Figure 1 FIG. 1 is a cross-sectional schematic diagram of a foldable optical waveguide near-eye display device of the present invention. Figure 1 As shown, a foldable optical waveguide near-eye display device of the present invention comprises: an image source 111, a cylindrical lens 121, a curved lens 131, a prism 141, and a prism group 151 in which two or more prisms are glued and connected in sequence.

[0027] Among them, part or all of a prism face of the prism 121 facing the image source 111 is set as a cylinder, that is, the cylinder can occupy the entire surface of the prism 121, or it can occupy part of the surface to reduce the volume. The concave surface of the cylinder faces the image source 111. The prism 121 is glued to one side of the prism 141 through a prism face other than the cylinder. In a specific embodiment of the present invention, the prism 121 adopts a cylinder with a curvature radius of less than 40mm. The connection surface between the prism 121 and the prism 141 is a first glued surface (the prism face of the prism 141 used for gluing can be greater than or equal to the surface of the prism 121 used for gluing), in order to better achieve transmission The first bonding surface is coated with a partially transmissive and partially reflective film (i.e., a spectroscopic film, which is to split the same beam of light so that part of the light is reflected and the remaining part is transmitted) or a reflective polarizing film. The prism 121 is also bonded to the curved lens 131 via another prism facet relative to the curved surface coated with a high-reflective film. The connecting surface between the prism 121 and the curved lens 131 is a second bonding surface. The second bonding surface is coated with a phase delay film or is not coated. If the first bonding surface is coated with a partially transmissive and partially reflective film, the second bonding surface may not be coated. If the first bonding surface is coated with a reflective polarizing film, the second bonding surface needs to be coated with a phase delay film. Preferably, a quarter phase delay film is applied to the second bonding surface. The angles formed by the first bonding surface and the axial direction of the cylindrical surface and the second bonding surface are preferably between 35 and 55 degrees. In a specific embodiment of the present invention, the prism 121 can be a cylindrical prism. In simple terms, part or all of one face of the prism is set as a cylindrical surface, and the other two faces are bonded to the prism 141 and the curved lens 131 respectively. In order to better achieve reflection, the curved surface of the curved lens 131 is coated with an inwardly high reflective film. In a specific embodiment of the present invention, the prism 141 is an unconventional prism, which can be formed by bonding two quadrangular prisms, one of which is a quadrangular prism. The prism is a trapezoidal prism. One side surface between the two bottom surfaces of the trapezoidal prism is glued to the first prism of the prism group 151, and the other side surface opposite to the side surface is glued to the prism surface of a quadrangular prism whose prism surfaces are not perpendicular to each other relative to the first glued surface to form a third glued surface. The size of the glued surface of the quadrangular prism whose prism surfaces are not perpendicular to each other is the same as that of the trapezoidal prism. After gluing, at least one prism surface is on the same plane as a bottom surface of the trapezoidal prism. In a specific embodiment of the present invention, the angle between the prism surface and the first glued surface is preferably not greater than 30 degrees. Of course, the quadrangular prism in the present invention can also be made into a non-cold-processed prism as shown in the figure, and the present invention is not limited thereto.The prism group 151 can be formed by gluing one or more parallelogram prisms and one trapezoidal prism in sequence, that is, the prism 141 is glued and connected with each prism in the prism group 151 in sequence, that is, the prism 141 is glued and connected with the first prism in the prism group 151, and the second prism in the prism group 151 is glued and connected with the first prism, and so on, each prism is glued and connected in sequence, and the last one to be glued is the trapezoidal prism. The connecting surfaces of the prism 141 and each prism in the prism group 151 are an array glued surface group, and each glued surface of the array glued surface group is parallel to each other, and the angle with the lower surface (which can refer to the surface close to the eye side or the surface away from the eye side) is greater than 30 degrees. The array glued surface is coated with a partially transmissive and partially reflective film. The present invention uses a reflector film with a horizontal tilt angle greater than 30 degrees, so that any imaging light of the image to be displayed is reflected or transmitted at most once on each array reflector lens, which can greatly reduce the attenuation of brightness. ;

[0028] The image source 111 may be a micro display screen, that is, an object surface of an imaging optical device. Light emitted from any field of view point of the object surface enters the prism 121 through the cylindrical surface of the prism 121. Since the concave surface of the cylindrical surface faces the image source 111, the incident angle scattered to both sides is reduced relative to the plane. Therefore, the use of a cylindrical surface with a curvature radius of less than 40 mm can increase the vertical field of view angle to more than 36 degrees. The image light is transmitted to the first bonding surface through the cylindrical surface. Since the first bonding surface is coated with a partially reflective and partially transmissive film or a reflective polarizing film (if it is a reflective polarizing film, it is required to A quarter phase delay film is coated on the second bonding surface), so most of the light is reflected by the first bonding surface and then enters the curved lens 131 through the second bonding surface. Since the curved surface of the curved lens is coated with an inward high-reflection film, an enlarged virtual image is formed after high reflection on the curved surface. The light reflected from the curved surface passes through the second bonding surface and the first bonding surface, and reaches the array bonding surface group of the prism group 151 after one or more total reflections in the prism 141. The array bonding surface group reflects the light to the human eye 161, so that a complete, high-quality, large-field-angle image can be seen.

[0029] Compared with the prior art, the present invention has the following advantages:

[0030] 1. The present invention adopts a reflection method of prism plus curved lens, which is significantly smaller and lighter than the lens imaging components of the prior art.

[0031] 2. The present invention adopts a reflective imaging method of cylindrical prism plus prism plus curved surface transmission, which can increase the vertical field angle from less than 25 degrees to more than 36 degrees, thereby further expanding the field angle without increasing the cost, and by using the left and right image sources to transmit partial images to combine into a complete large field angle image in the human eye, the horizontal field angle can be increased from less than 40 degrees to more than 55 degrees.

[0032] 3. The present invention uses a reflector film with a horizontal tilt angle greater than 30 degrees, so that any imaging light of the image to be displayed is reflected or transmitted at most once on each array reflector lens, which can greatly reduce the attenuation of brightness.

[0033] 4. The present invention adopts a reflector film with a horizontal tilt angle greater than 30 degrees. The image light is reflected or transmitted at most once through any array reflector, ensuring the brightness uniformity of reflection and transmission, thereby reducing the number of coating layers of the array reflective lens, improving the yield, and ensuring the purity of the reflected image on each array reflective lens, providing users with high-quality image enjoyment.

[0034] The above embodiments are only illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Any person skilled in the art may modify and change the above embodiments without violating the spirit and scope of the present invention. Therefore, the scope of protection of the present invention shall be as set forth in the claims.

Claims

1. A foldable optical waveguide near-eye display device, comprising: An image source (111), a prism (121) with a cylindrical surface, a curved lens (131), a prism (141), and a prism group (151) composed of two or more prisms glued together in sequence, wherein a prism face of the prism (121) is partially or entirely a cylindrical surface, and the cylindrical surface faces the image source (111); the prism (121) is connected to the prism (141) via a prism face other than the cylindrical surface to form a first glued surface; the prism (121) is connected to the surface opposite to the curved surface of the curved lens (131) via another prism face other than the cylindrical surface to form a second glued surface; the prism (141) and each prism of the prism group (151) are glued together in sequence; The connecting surfaces of the prism (141) and each prism of the prism group (151) are an array bonding surface group, and the bonding surfaces of the array bonding surface group are parallel to each other and have an angle greater than 30 degrees with the lower surface.

2. A foldable optical waveguide near-eye display device as claimed in claim 1, characterized in that: The concave surface of the cylinder faces the image source (111).

3. A foldable optical waveguide near-eye display device as claimed in claim 2, characterized in that: The curvature radius of the cylindrical surface is less than 40 mm.

4. The foldable optical waveguide near-eye display device according to claim 1, characterized in that: The angles formed by the first bonding surface and the axial direction of the cylindrical surface and the second bonding surface are both between 35 and 55 degrees.

5. A foldable optical waveguide near-eye display device as claimed in claim 4, characterized in that: The first bonding surface is coated with a partially transmissive and partially reflective film or a reflective polarizing film.

6. A foldable optical waveguide near-eye display device as claimed in claim 5, characterized in that: If the first bonding surface is coated with a reflective polarizing film, a quarter phase delay film is additionally coated on the second bonding surface.

7. The foldable optical waveguide near-eye display device according to claim 1, characterized in that: The curved surface of the curved lens (131) is coated with an inwardly directed high-reflection film.

8. The foldable optical waveguide near-eye display device according to claim 1, characterized in that: The prisms (141) and the prism group (151) are sequentially glued to form an array of glued surfaces, and the glued surfaces are parallel to each other and have an angle greater than 30 degrees with the lower surface.

9. A foldable optical waveguide near-eye display device as claimed in claim 8, characterized in that: The array bonding surface is plated with a partially transmissive and partially reflective film.

10. The foldable optical waveguide near-eye display device according to claim 1, characterized in that: The prism (141) is synthesized by gluing a trapezoidal prism and a quadrangular prism whose facets are not perpendicular to each other; a side surface between two bottom surfaces of the trapezoidal prism is glued to the first prism of the prism group (151); another side surface opposite to the side surface is glued to the facet of the quadrangular prism whose facets are not perpendicular to each other relative to the first gluing surface to form a third gluing surface; after gluing, at least one facet of the quadrangular prism whose facets are not perpendicular to each other is on the same plane as a bottom surface of the trapezoidal prism.

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