CN114740600A - Optical projection system and electronic equipment - Google Patents
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B13/00—Optical objectives specially designed for the purposes specified below
- G02B13/001—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras
- G02B13/0015—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras characterised by the lens design
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B13/00—Optical objectives specially designed for the purposes specified below
- G02B13/001—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras
- G02B13/0055—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras employing a special optical element
- G02B13/006—Miniaturised objectives for electronic devices, e.g. portable telephones, webcams, PDAs, small digital cameras employing a special optical element at least one element being a compound optical element, e.g. cemented elements
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B13/00—Optical objectives specially designed for the purposes specified below
- G02B13/16—Optical objectives specially designed for the purposes specified below for use in conjunction with image converters or intensifiers, or for use with projectors, e.g. objectives for projection TV
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- G—PHYSICS
- G02—OPTICS
- G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
- G02B27/00—Optical systems or apparatus not provided for by any of the groups G02B1/00 - G02B26/00, G02B30/00
- G02B27/01—Head-up displays
- G02B27/0101—Head-up displays characterised by optical features
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- G—PHYSICS
- G03—PHOTOGRAPHY; CINEMATOGRAPHY; ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ELECTROGRAPHY; HOLOGRAPHY
- G03B—APPARATUS OR ARRANGEMENTS FOR TAKING PHOTOGRAPHS OR FOR PROJECTING OR VIEWING THEM; APPARATUS OR ARRANGEMENTS EMPLOYING ANALOGOUS TECHNIQUES USING WAVES OTHER THAN OPTICAL WAVES; ACCESSORIES THEREFOR
- G03B21/00—Projectors or projection-type viewers; Accessories therefor
- G03B21/14—Details
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Abstract
The application discloses an optical projection system and an electronic device. From the magnification side to the reduction side, the optical projection system includes: the optical projection system comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens, wherein the effective focal length of the optical projection system is as follows: 4.5mm < eff <6.7mm, the optical projection system satisfying the following relation: 3.5< TL/D <5, where TL is the total optical length of the optical projection system and D is the maximum lens aperture in the optical projection system.
Description
Technical Field
The present application relates to the field of optical devices, and more particularly, to an optical projection system and an electronic device.
Background
At present, the optical projection system is developed rapidly and has wide application fields. For example, projection optical systems are applied to Digital Light Processing (DLP) projection apparatuses, Augmented Reality (AR) apparatuses, and Virtual Reality (VR) apparatuses. The image definition, the picture size and the picture distortion image quality of the projection product are directly determined by the design quality of the optical projection system.
Therefore, in the case of reducing the volume of the imaging system, it is one of the urgent needs to solve the problem in the optical design field to design an optical system with a light emitting surface size of 0.2 inch DMD, a projection ratio of 1.1, and good imaging quality.
Disclosure of Invention
An object of the present application is to provide a new technical solution for an optical projection system and an electronic device.
According to a first aspect of embodiments herein, there is provided an optical projection system. The optical projection system includes:
the device comprises the following components in sequence from an amplification side to a reduction side: the optical projection system comprises a first lens, a second lens, a third lens, a fourth lens, a fifth lens and a sixth lens, wherein the effective focal length of the optical projection system is as follows: 4.5mm < eff <6.7mm, the optical projection system satisfying the following relationship: 3.5< TL/D <5, where TL is the total optical length of the optical projection system and D is the maximum lens aperture in the optical projection system.
Optionally, the optical projection system has, in order from the magnification side to the reduction side: negative positive/positive negative positive.
Optionally, the fourth lens and the fifth lens are cemented to form a first cemented lens, or the fourth lens and the fifth lens are cemented to form a first cemented lens, and the second lens and the third lens are cemented together to form a second cemented lens.
Optionally, a distance between the second lens and the third lens is d1, and a distance between the first lens and the sixth lens is L, where: d1/L < 0.2.
Optionally, a distance between the first lens and the sixth lens is L, and a distance between the third lens and the fourth lens is d2, wherein d2/L < 0.5.
Optionally, a diaphragm is disposed between the third lens and the fourth lens, a distance between the third lens and the diaphragm is d3, and a distance between the fourth lens and the diaphragm is d4, wherein 0.7< d3/d4< 1.3.
Optionally, the first lens has a first face facing away from the second lens, and the first lens has a second face disposed adjacent to the second lens, the first face having a radius D1, the second face having a radius D2, wherein 2 ≦ D1/D2 ≦ 5.
Optionally, the optical projection system satisfies the following relationship: -10mm < f1< -6.6mm, -20mm < f2< -16.7mm, 6mm < f3<11mm, 9mm < f4<13mm, -15mm < f5< -9mm, 7mm < f6<12.6 mm;
wherein f1 is the effective focal length of the first lens element, f2 is the effective focal length of the second lens element, f3 is the effective focal length of the third lens element, f4 is the effective focal length of the fourth lens element, f5 is the effective focal length of the fifth lens element, and f6 is the effective focal length of the sixth lens element.
Optionally, the first surface of the first lens is a convex surface, and the second surface of the first lens is a concave surface; the second surface of the second lens is a concave surface; the first surface and the second surface of the third lens are convex surfaces; the first surface of the fourth lens is a concave surface or a plane, and the second surface of the fourth lens is a convex surface; the first surface of the fifth lens is a concave surface, and the second surface of the fifth lens is a convex surface; the first surface and the second surface of the sixth lens are convex surfaces; wherein the first surface of each lens is disposed closer to the magnification side than the second surface thereof.
According to a second aspect of embodiments of the present application, there is provided an electronic device comprising the optical projection system according to the first aspect.
In the embodiment of the application, an optical projection system is provided, and the number of lenses in the optical projection system, the effective focal length of the optical projection system, and the ratio of the total optical length of the optical projection system to the maximum lens aperture are limited, so that the optical projection system is compact in structure, the volume of the optical projection system is reduced, and the imaging quality of the optical projection system is improved.
Other features of the present application and advantages thereof will become apparent from the following detailed description of exemplary embodiments thereof, which proceeds with reference to the accompanying drawings.
Drawings
The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the application and together with the description, serve to explain the principles of the application.
Fig. 1 is a schematic structural diagram of an optical projection system according to the present application.
Fig. 2 is a schematic structural diagram of an optical projection system according to the present application.
FIG. 3 is a first plot of modulation transfer functions for each field of view for an embodiment of the optical projection system of the present application.
FIG. 4 is a diagram of the modulation transfer function for each field of view of an embodiment of the optical projection system of the present application.
FIG. 5 is a defocus plot of an embodiment of the optical projection system of the present application.
FIG. 6 is a diagram illustrating modulation transfer functions for each field of view of another embodiment of an optical projection system of the present application.
FIG. 7 is a defocus plot of another embodiment of the optical projection system of the present application.
Description of reference numerals:
1. a first lens; 2. a second lens; 3. a third lens; 4. a fourth lens; 5. a fifth lens; 6. a sixth lens; 7. a diaphragm; 8. an image source; 9. a plate glass; 10. a prism; 20. a first lens group; 30. a second lens group.
Detailed Description
Various exemplary embodiments of the present application will now be described in detail with reference to the accompanying drawings. It should be noted that: the relative arrangement of the components and steps, the numerical expressions, and numerical values set forth in these embodiments do not limit the scope of the present application unless specifically stated otherwise.
The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the application, its application, or uses.
Techniques and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail, but are intended to be considered a part of the specification where appropriate.
In all examples shown and discussed herein, any particular value should be construed as merely illustrative, and not limiting. Thus, other examples of the exemplary embodiments may have different values.
It should be noted that: like reference numbers and letters refer to like items in the following figures, and thus, once an item is defined in one figure, further discussion thereof is not required in subsequent figures.
The application provides an optical projection system, which is applied to a projection device. For example, the optical projection system can be applied to a projection light machine, an illumination light machine and the like. Or the optical projection system may be applied to an AR (augmented reality) device or a VR (virtual reality) device.
VR (Virtual Reality) is a computer simulation system that can create and experience Virtual worlds, which uses computers to create a simulated environment, which is a systematic simulation of multi-information-fused, interactive, three-dimensional dynamic views and physical behaviors, to immerse users in the environment. The application of the optical projection system is applied to VR, and the imaging picture of VR equipment is improved under the condition that the size of the VR equipment is reduced.
AR (Augmented Reality) is a technology for increasing a user's perception of the real world by generating virtual image information using a computer system. The AR technology aims to superimpose information such as virtual objects, images, characters and the like generated by a computer onto a real scene to create a virtual-real combined world, and realize interaction of the virtual-real scene through image recognition, tracking, registration technology, cloud technology and the like, thereby realizing 'enhancement' of the real world. The application of the optical projection system to VR has the advantages that the imaging picture of AR equipment is improved under the condition that the size of the AR equipment is reduced.
Referring to fig. 1 and 2, the optical projection system includes, from an enlargement side to a reduction side: a first lens 1, a second lens 2, a third lens 3, a fourth lens 4, a fifth lens 5 and a sixth lens 6, wherein the effective focal length of the optical projection system is as follows: 4.5mm < eff <6.7mm, the optical projection system satisfying the following relationship: 3.5< TL/D <5, where TL is the total optical length of the optical projection system and D is the maximum lens aperture in the optical projection system.
In this embodiment, the image source 8, the plate glass 9, the prism 10, the sixth lens 6, the fifth lens 5, the fourth lens 4, the third lens 3, the second lens 2, and the first lens 1 in the optical projection system are disposed between the reduction side and the enlargement side in this order along the same optical axis, including the reduction side and the enlargement side in the light transmission direction. Wherein, the reduction side is the side where the image source 8 (such as a DMD chip) generating the projection light is located in the projection process, namely the image side; the enlargement side is the side where a projection surface (such as a projection screen) for displaying a projection image is located during projection, i.e., the object side. The transmission direction of the projection light is from the reduction side to the enlargement side. However, in designing an optical projection system in practice, light rays are simulated from the actual enlargement side to the actual reduction side based on the principle of reversible optical paths.
Specifically, in an actual projection process, projection light is emitted from an image source 8, emitted from a reduction side toward an enlargement side, and passes through a plate glass 9, a prism 10, a sixth lens 6, a fifth lens 5, a fourth lens 4, a third lens 3, a second lens 2, and a first lens 1 in this order to display a projection image.
In the embodiment of the present application, the image source 8 may be a Digital Micromirror Device (DMD) chip. The DMD is composed of many digital micromirrors arranged in a matrix, and each micromirror can deflect and lock in both forward and reverse directions during operation, so that light is projected in a predetermined direction and swings at a frequency of tens of thousands of hertz, and light beams from an illumination light source enter an optical system through the inverted reflection of the micromirror to be imaged on a screen. The DMD has the advantages of high resolution, no need of digital-to-analog conversion for signals and the like. This embodiment is suitable for a 0.2 "DMD, with a throw ratio of 1:1, 160% offset (off-axis) design. Specifically, the present embodiment is suitable for a 0.2 "DMD with a size aspect ratio of 16:9, specifically 4.6116 × 2.592mm, a design throw ratio of 1.1, and a max _ offset of 160%. Of course, the image source 8 may also be a Liquid Crystal On Silicon (LCOS) chip or other display elements that can be used to emit light, which is not limited in this application.
In this embodiment, the optical projection system of the present application is designed based on the light emitting surface size of a DMD (0.2 ″ digital micromirror device) and the optical path architecture of the imaging design with a projection ratio of 1.1, which is different from the current architecture of seven lenses or more, and the optical projection system of the present application only includes six lenses, so as to reduce the volume of the optical projection system; meanwhile, the optical projection system of the present embodiment satisfies the following relationship: 3.5< TL/D <5, where TL is the total optical length of the optical projection system (the total optical length is the distance between the vertex of the light-emitting surface of the first lens 1 and the back surface of the image source 8 (the surface facing away from the sixth lens 6) along the optical axis direction), and D is the maximum lens aperture in the optical projection system, and the total length and the radius of the optical projection system can be controlled, so that the optical projection system has a compact structure, and the volume and the size of the optical projection system are ensured to be small to a certain extent, and the optical projection system is convenient to carry and use.
In the embodiment, the effective focal length of the optical projection system is limited in the range, and the imaging effect of the optical projection system is improved under the condition of reducing the volume of the optical projection system. Specifically, the effective focal length of the optical projection system is limited, so that the MTF of the full field of view of the optical projection system is more than 0.5@96lp/mm, and the imaging quality of the optical projection system is improved.
In one embodiment, the optical power sequence of the optical projection system from the magnification side to the reduction side is: negative positive/positive negative positive.
In this embodiment, the optical projection system has a power order of negative positive/positive negative positive. That is, in the optical projection system, the first lens 1, the second lens 2, and the third lens 3 constitute a first lens group 20. The fourth lens 4, the fifth lens 5, and the sixth lens 6 constitute a second lens group 30. In this embodiment, the power of the first lens group 20 is negative, and the power of the second lens group 30 is positive. The powers of the first lens group 20 and the second lens group 30 are reasonably distributed to balance the overall power of the optical projection system.
In one embodiment, the fourth lens 4 and the fifth lens 5 are cemented to form a first cemented lens, or the fourth lens 4 and the fifth lens 5 are cemented to form a first cemented lens, and the second lens 2 and the third lens 3 are cemented to form a second cemented lens.
In this embodiment, the first lens 1, the second lens 2, and the third lens 3 are combined to form a first lens group 20, and the first lens group 20 is a lens front group of the optical projection system. The fourth lens 4, the fifth lens 5 and the sixth lens 6 are combined to form a second lens group 30, and the second lens group 30 is a lens rear group of the optical projection system.
In one embodiment, referring to fig. 2, in the second lens group 30, the fourth lens 4 and the fifth lens 5 are cemented to form a first cemented lens. Namely, the rear lens group comprises a cemented lens, which can effectively reduce chromatic aberration generated in the optical imaging process.
In another embodiment, referring to fig. 1, in the first lens group 20, the second lens 2 and the third lens 3 are cemented to form a second cemented lens, while in the second lens group 30, the fourth lens 4 and the fifth lens 5 are cemented to form a first cemented lens. That is, in the front lens group, one cemented lens is included, while in the rear lens group, one cemented lens is included. Specifically, the optical projection system comprises six lenses, and two lenses close to the diaphragm 7 in the front lens group are cemented, and two lenses close to the diaphragm 7 in the rear lens group are cemented, so that the chromatic aberration generated in the optical imaging process can be further reduced under the condition of combining the 0.2 ″ DMD size requirement and 160% offset requirement.
In this embodiment, the first lens 1 is mainly used for less than imaging distortion for the entire optical projection system. The sixth lens 6 and the first lens 1 are mainly used for eliminating spherical aberration of imaging. The second lens 2 and the third lens 3 are connected in a gluing mode and are mainly used for further eliminating imaging chromatic aberration; the fourth lens 4 and the fifth lens 5 are connected by gluing and are mainly used for eliminating imaging chromatic aberration.
In one embodiment, referring to fig. 2, a distance between the second lens 2 and the third lens 3 is d1, and a distance between the first lens 1 and the sixth lens 6 is L, wherein: d1/L < 0.2.
In this embodiment, the second lens 2 is provided separately from the third lens 3. In this embodiment, based on the optical projection system architecture described above, the optical projection system includes six lenses, from the enlargement side to the reduction side, the power order of the six lenses is negative positive/positive negative positive, and the effective focal length of the optical projection system is 4.5mm < eff <6.7mm, and the optical projection system satisfies the relationship of 3.5< TL/D <5, where TL is the total optical length of the optical projection system and D is the maximum lens aperture in the optical projection system), and further the ratio of the distances between the lenses is defined to optimize the optical projection system.
Specifically, in the first lens group 20, if the second lens 2 and the third lens 3 are not glued together, that is, the second lens 2 and the third lens 3 are disposed separately, the distance between the second lens 2 and the third lens 3 is d1, that is, the distance between two surfaces of the second lens 2 and the third lens 3 disposed adjacent to each other is d 1. A distance between the first lens 1 and the sixth lens 6 is L, that is, a distance between the light incident surface of the first lens 1 and the light emitting surface of the sixth lens 6 in the optical axis direction is L, and referring to fig. 2, that is, a distance between the S2 surface and the S11 surface is L.
The present embodiment defines the ratio of the distance between the second lens 2 and the third lens 3 to the distance between the first lens 1 and the sixth lens 6, and optimizes the optical projection system parameters. Specifically, the optical imaging system can obtain a high-quality picture under the condition that the optical imaging system is matched with the requirements of 0.2' DMD size and 160% offset design, and the distortion and the chromatic aberration of the imaged picture are small. If d1/L is not within this range, the optical projection system will have poor image quality.
In an alternative embodiment, the distance between the second lens 2 and the third lens 3 is d1, and the distance between the first lens 1 and the sixth lens 6 is L, wherein: d1/L <0.2, while the distance between the first lens 1 and the sixth lens 6 is L, the distance between the third lens 3 and the fourth lens 4 is d2, where d2/L < 0.5. The optical imaging system can obtain a high-quality picture under the condition that the optical imaging system is matched with 0.2' DMD size requirement and 160% offset design requirement, and the distortion of the imaged picture is small, the chromatic aberration is small, and the spherical aberration is small.
In one embodiment, referring to fig. 1, a distance between the first lens 1 and the sixth lens 6 is L, and a distance between the third lens 3 and the fourth lens 4 is d2, wherein d2/L < 0.5.
In this embodiment, the second lens 2 and the third lens 3 are cemented. In this embodiment, based on the optical projection system architecture described above, the optical projection system includes six lenses, from the enlargement side to the reduction side, the power order of the six lenses is negative positive/positive negative positive, and the effective focal length of the optical projection system is 4.5mm < eff <6.7mm, and the optical projection system satisfies the relationship of 3.5< TL/D <5, where TL is the total optical length of the optical projection system and D is the maximum lens aperture in the optical projection system), and further the ratio of the distances between the lenses is defined to optimize the optical projection system.
In this embodiment, the distance between the third lens 3 and the fourth lens 4 is d2, i.e., the distance between the third lens 3 and the fourth lens 4 on the optical axis is d 2. In the optical projection system, the first lens 1, the second lens 2, and the third lens 3 constitute a first lens group 20. The fourth lens 4, the fifth lens 5, and the sixth lens 6 constitute the second lens group 30, i.e., the distance between the first lens group 20 and the second lens group 30 is d 2. Referring to fig. 1, the distance between the S5 plane and the S8 plane is d 2. A distance between the first lens element 1 and the sixth lens element 6 is L, that is, a distance between the light incident surface of the first lens element 1 and the light emitting surface of the sixth lens element 6 in the optical axis direction, and referring to fig. 2, a distance between the S2 surface and the S11 surface in the optical axis direction is L.
The present embodiment defines the ratio of the distance between the third lens 3 and the fourth lens 4 to the distance between the first lens 1 and the sixth lens 6, and further optimizes the imaging parameters of the optical projection system. Specifically, the optical imaging system is suitable for the size requirement of a 0.2' DMD, the design of 160% offset improves the imaging quality of the optical imaging system, and reduces the spherical aberration and chromatic aberration of imaging.
In one embodiment, referring to fig. 1 and 2, a stop 7 is disposed between the third lens 3 and the fourth lens 4, a distance between the third lens 3 and the stop 7 is d3, and a distance between the fourth lens 4 and the stop 7 is d4, wherein 0.7< d3/d4< 1.3.
In this embodiment, a stop 7 is disposed between the third lens 3 and the fourth lens 4, i.e., the stop 7 is disposed between the first lens group 20 and the second lens group 30. The third lens 3 closest to the stop 7 in the first lens group 20 is at a distance d3 from the stop 7, and the fourth lens 4 closest to the stop 7 in the second lens group 30 is at a distance d4 from the stop 7. Wherein 0.7< d3/d4< 1.3. In this embodiment, the ratio of the distance between the third lens 3 and the diaphragm 7 to the distance between the fourth lens 4 and the diaphragm 7 is limited, so that the total optical length is reduced, the optical projection system is miniaturized, and spherical aberration and image distortion can be better corrected.
In one embodiment, as shown with reference to FIGS. 1 and 2, the first lens 1 has a first face facing away from the second lens 2, and the first lens 1 has a second face disposed adjacent to the second lens 2, the first face having a radius D1, the second face having a radius D2, wherein 2 ≦ D1/D2 ≦ 5.
In this embodiment, the ratio of the radius of the first face in the first lens 1 to the radius of the second face in the first lens 1 is defined, the radius of the first face being larger than the radius of the second face, while 2 ≦ D1/D2 ≦ 5, e.g. D1/D2 ═ 2, or D1/D2 ≦ 3; D1/D2 is 4; D1/D2 is 5.
Specifically, the ratio of the radius of the first surface in the first lens 1 and the radius of the second surface in the first lens 1 is defined to define the first lens 1 shape. The first lens 1 is of a meniscus shape, a large field angle can be achieved, distortion can be better eliminated by the first lens 1, and imaging quality of the optical projection system is improved.
In one embodiment, the optical projection system satisfies the following relationship: -10mm < f1< -6.6mm, -20mm < f2< -16.7mm, 6mm < f3<11mm, 9mm < f4<13mm, -15mm < f5< -9mm, 7mm < f6<12.6 mm;
wherein f1 is an effective focal length of the first lens element 1, f2 is an effective focal length of the second lens element 2, f3 is an effective focal length of the third lens element 3, f4 is an effective focal length of the fourth lens element 4, f5 is an effective focal length of the fifth lens element 5, and f6 is an effective focal length of the sixth lens element 6.
In this embodiment, the effective focal length of each lens is defined to improve the optical projection system side image quality.
In one embodiment, the first surface of the first lens 1 is a convex surface, and the second surface of the first lens 1 is a concave surface; the second surface of the second lens 2 is a concave surface; the first surface and the second surface of the third lens 3 are convex surfaces; the first surface of the fourth lens 4 is a concave surface or a plane, and the second surface of the fourth lens 4 is a convex surface; the first surface of the fifth lens 5 is a concave surface, and the second surface of the fifth lens 5 is a convex surface; the first surface and the second surface of the sixth lens 6 are convex surfaces; wherein the first surface of each lens is disposed closer to the magnification side than the second surface thereof.
Specifically, the first lens 1 is a meniscus lens having a negative power; the second lens 2 is a lens having negative power, for example, the second lens 2 is a biconcave lens having negative power, or a meniscus lens having negative power; the third lens 3 is a biconvex lens with positive focal power; and the second lens 2 is cemented with the third lens 3; the fourth lens 4 is a concave-convex lens with a positive focal length, or the fourth lens 4 is a plano-convex lens with a positive focal length; the fifth lens 5 is a concave-convex lens with negative focal power, the fourth lens 4 is glued with the fifth lens 5, and the sixth lens 6 is a biconvex lens with positive focal power
The optical projection system is suitable for a 0.2' DMD, and can effectively reduce chromatic aberration generated in the optical imaging process when the projection ratio is 1:1 and 160% offset (off-axis) is designed. The embodiment of the application limits the surface type and the focal power of each lens in the optical projection system and limits the number of the lenses in the optical projection system, so that the optical projection system is suitable for a 0.2' DMD, the projection ratio is 1:1, and 160% offset (off-axis) design, and the imaging quality of the optical projection system is improved.
According to a second aspect of embodiments of the present application, an electronic device is provided. The electronic device comprises the optical projection system of the first aspect. The electronic device may be, for example, a projection light machine, a smart headset. Wherein the smart headset may be Augmented Reality (AR) glasses, Virtual Reality (VR) glasses, or the like.
Example 1
In a specific embodiment, the total effective focal length eff of the optical projection system is 5.113mm, and the total length of the system is 33 mm.
Referring to fig. 1, the first lens element 1 is a plastic aspheric lens, the first surface S1 of the first lens element 1 is a convex surface, and the second surface S2 is a concave surface; the second lens 2 and the third lens 3 are both glass lenses, the second lens 2 and the third lens 3 are double-cemented lenses, the first surface S3 of the second lens 2 is a concave surface, and the second surface S4 is a concave surface; the first surface S4 of the third lens element 3 is convex, and the second surface S5 is convex; the fourth lens 4 and the fifth lens 5 are both glass lenses, the fourth lens 4 and the fifth lens 5 are double-cemented lenses, the first surface S8 of the fourth lens 4 is a concave surface, and the second surface S9 is a convex surface; the first surface S9 of the fifth lens element 5 is a concave surface; the second surface S10 is a convex surface; the sixth lens 6 is a glass aspheric lens, and the sixth lens 6 has a convex first surface S11 and a convex second surface S12.
Wherein, the effective focal length f1 of the first lens 1 is-8.645 mm; the effective focal length f2 of the second lens 2 is-18.751 mm; the effective focal length f3 of the third lens 3 is 9.159 mm; the effective focal length f4 of the fourth lens 4 is 11.417 mm; the effective focal length f4 of the fifth lens 5 is-12.585 mm; the effective focal length f4 of the sixth lens 6 is 10.635 mm.
The optical projection system is suitable for the size of a 0.2' DMD, the transverse-longitudinal ratio is 16:9, the specific size is 4.6116 × 2.592mm, the designed projection ratio is 1.1, and the max _ offset is 160%.
The parameters of each lens are shown in table 1:
in this embodiment, the optical projection system meets the design requirements, i.e. the optical projection system is suitable for a size of 0.2 "DMD, the aspect ratio is 16:9, the specific size is 4.6116 × 2.592mm, the optical projection system meets the projection ratio 1:1, the projection distance is 300mm, the offset is 160%, the wavelength RGB, TV distortion is less than 0.5%, the full field MTF > 0.5@96lp/mm, the telecentricity < 1%, and the chromatic aberration <0.5pixel F # is 1.7.
The measured parameters of the fields of view of the optical imaging module are shown in fig. 3 to 5.
Fig. 3 shows a Modulation Transfer Function (MTF) diagram according to the present embodiment. Fig. 3 is a diagram of the modulation transfer function of the projection optical system at different image heights. Wherein the horizontal axis is Spatial Frequency in cycles per mm and the vertical axis is OTF Modulus (Modulus of the OTF). As can be seen from the figure, the OTF modulus of an image in the interval of 0mm to 93mm in spatial frequency can be always maintained at 0.5 or more, generally speaking, the higher the quality of the image is as the OTF modulus approaches 1, but due to the influence of various factors, the OTF modulus does not exist at 1, and generally, when the OTF modulus can be maintained at 0.5 or more, it means that the image has high imaging quality and the definition of the picture is excellent, referring to fig. 3, the MTF value of each field is higher than 0.5, and it can be seen that the image definition after being imaged by the system in each field is excellent.
Fig. 4 is a diagram of modulation transfer function for each field of view tolerance according to an embodiment of the present application. Referring to FIG. 3, the MTF values for each field perform well under normal tolerances.
Fig. 5 shows a defocus graph of an optical projection system according to an embodiment of the present application. Referring to FIG. 5, the defocus range >20um @ MTF0.4, and therefore the optical projection system has greatly reduced assembly requirements.
Example 2
In a specific embodiment, the total effective focal length eff of the optical projection system is 5.2mm, and the total length of the system is 35 mm.
Referring to fig. 2, the first lens element 1 is a plastic aspheric lens, the first surface S1 of the first lens element 1 is a convex surface, and the second surface S2 is a concave surface; the second lens 2 and the third lens 3 are both glass lenses, the first surface S3 of the second lens 2 is a concave surface, and the second surface S4 is a concave surface; the first surface S5 of the third lens element 3 is convex, and the second surface S6 is convex; the fourth lens 4 and the fifth lens 5 are both glass lenses, the fourth lens 4 and the fifth lens 5 are double-cemented lenses, the first surface S8 of the fourth lens 4 is a concave surface, and the second surface S9 is a convex surface; the first surface S9 of the fifth lens element 5 is concave; the second surface S10 is a convex surface; the sixth lens element 6 is a glass aspherical lens, and the sixth lens element 6 has a convex first surface S11 and a convex second surface S12.
In this embodiment, the effective focal length f1 of the first lens 1 is-9.45 mm; the effective focal length f2 of the second lens 2 is-20.151 mm; the effective focal length f3 of the third lens 3 is 8.01 mm; the effective focal length f4 of the fourth lens 4 is 10.77 mm; the effective focal length f4 of the fifth lens 5 is-10.417 mm; the effective focal length f4 of the sixth lens 6 is 7.535 mm.
The optical projection system is suitable for the size of 0.2' DMD, the transverse-longitudinal ratio is 16:9, the specific size is 4.6116 × 2.592mm, the designed projection ratio is 1.1, and the max _ offset is 160%.
The parameters of each lens are shown in table 2:
in this embodiment, the optical projection system meets the design requirements, i.e. the optical projection system is suitable for a size of 0.2 "DMD, the aspect ratio is 16:9, the specific size is 4.6116 × 2.592mm, the optical projection system meets the projection ratio 1:1, the projection distance is 300mm, the offset is 160%, the wavelength RGB, TV distortion is less than 0.5%, the full field MTF > 0.5@96lp/mm, the telecentricity <1 °, the chromatic aberration <0.5pixel, and the F # is 1.7.
The measured parameters of the fields of view of the optical imaging module are shown in fig. 6 to 7.
Fig. 6 shows a Modulation Transfer Function (MTF) diagram according to the present embodiment. Fig. 6 is a diagram of the modulation transfer function of the projection optical system at different image heights. Wherein the horizontal axis is Spatial Frequency in cycles per mm and the vertical axis is the OTF Modulus (Modulus of the OTF). As can be seen from the figure, the OTF module value of an image in the interval of the spatial frequency of 0mm to 93mm can be always maintained at 0.55 or more, generally, the higher the OTF module value is closer to 1, but due to the influence of various factors, the OTF module value is not 1, and generally, when the OTF module value can be maintained at 0.55 or more, it means that the image has high imaging quality and the definition of the picture is excellent, referring to fig. 6, the MTF value of each field is higher than 0.55, and it is seen that the definition of the image imaged by the system in each field is excellent.
Fig. 7 is a graph showing a defocus curve of the optical projection system according to the embodiment of the present application. Referring to FIG. 7, the defocus range >18um @ MTF0.4, and therefore the optical projection system has greatly reduced assembly requirements.
In the above embodiments, the differences between the embodiments are described in emphasis, and different optimization features between the embodiments can be combined to form a better embodiment as long as the differences are not contradictory, and further description is omitted here in consideration of brevity of the text.
Although some specific embodiments of the present application have been described in detail by way of example, it should be understood by those skilled in the art that the above examples are for illustration only and are not intended to limit the scope of the present application. It will be appreciated by those skilled in the art that modifications may be made to the above embodiments without departing from the scope and spirit of the present application. The scope of the application is defined by the appended claims.
Claims (10)
1. An optical projection system comprising, in order from an enlargement side to a reduction side: a first lens (1), a second lens (2), a third lens (3), a fourth lens (4), a fifth lens (5) and a sixth lens (6), the effective focal length of the optical projection system being: 4.5mm < eff <6.7mm, the optical projection system satisfying the following relationship: 3.5< TL/D <5, where TL is the total optical length of the optical projection system and D is the maximum lens aperture in the optical projection system.
2. The optical projection system of claim 1, wherein the optical projection system has, in order from the magnification side to the reduction side: negative positive/positive negative positive.
3. The optical projection system of claim 1, wherein the fourth lens (4) and the fifth lens (5) are cemented to form a first cemented lens, and the second lens (2) and the third lens (3) are cemented to form a second cemented lens.
4. The optical projection system according to claim 1, characterized in that the distance between the second lens (2) and the third lens (3) is d1 and the distance between the first lens (1) and the sixth lens (6) is L, wherein: d1/L < 0.2.
5. The optical projection system according to claim 1, characterized in that the distance between the first lens (1) and the sixth lens (6) is L, the distance between the third lens (3) and the fourth lens (4) is d2, wherein d2/L < 0.5.
6. The optical projection system according to claim 1, characterized in that a diaphragm (7) is arranged between the third lens (3) and the fourth lens (4), the distance between the third lens (3) and the diaphragm (7) being d3, the distance between the fourth lens (4) and the diaphragm (7) being d4, wherein 0.7< d3/d4< 1.3.
7. The optical projection system as claimed in claim 1, characterized in that the first lens (1) has a first face facing away from the second lens (2), and the first lens (1) has a second face arranged adjacent to the second lens (2), the first face having a radius D1 and the second face having a radius D2, wherein 2 ≦ D1/D2 ≦ 5.
8. The optical projection system of claim 1, wherein the optical projection system satisfies the following relationship: -10mm < f1< -6.6mm, -20mm < f2< -16.7mm, 6mm < f3<11mm, 9mm < f4<13mm, -15mm < f5< -9mm, 7mm < f6<12.6 mm;
wherein f1 is the effective focal length of the first lens (1), f2 is the effective focal length of the second lens (2), f3 is the effective focal length of the third lens (3), f4 is the effective focal length of the fourth lens (4), f5 is the effective focal length of the fifth lens (5), and f6 is the effective focal length of the sixth lens (6).
9. The optical projection system of claim 1,
the first surface of the first lens (1) is a convex surface, and the second surface of the first lens (1) is a concave surface;
the second surface of the second lens (2) is a concave surface;
the first surface and the second surface of the third lens (3) are convex surfaces;
the first surface of the fourth lens (4) is a concave surface or a plane, and the second surface of the fourth lens (4) is a convex surface;
the first surface of the fifth lens (5) is a concave surface, and the second surface of the fifth lens (5) is a convex surface;
the first surface and the second surface of the sixth lens (6) are convex surfaces;
wherein the first surface of each lens is disposed closer to the magnification side than the second surface thereof.
10. An electronic device, characterized in that the electronic device comprises an optical projection system as claimed in any one of claims 1-9.
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202210343057.6A CN114740600A (en) | 2022-03-31 | 2022-03-31 | Optical projection system and electronic equipment |
| PCT/CN2022/101699 WO2023184752A1 (en) | 2022-03-31 | 2022-06-28 | Optical projection system and electronic device |
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| Application Number | Priority Date | Filing Date | Title |
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| CN202210343057.6A CN114740600A (en) | 2022-03-31 | 2022-03-31 | Optical projection system and electronic equipment |
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| CN114740600A true CN114740600A (en) | 2022-07-12 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202210343057.6A Pending CN114740600A (en) | 2022-03-31 | 2022-03-31 | Optical projection system and electronic equipment |
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| Country | Link |
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| CN (1) | CN114740600A (en) |
| WO (1) | WO2023184752A1 (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116400482A (en) * | 2023-05-26 | 2023-07-07 | 合肥综合性国家科学中心人工智能研究院(安徽省人工智能实验室) | Miniature wide-field objective lens for multispectral imaging |
| CN116643409A (en) * | 2023-07-18 | 2023-08-25 | 沂普光电(天津)有限公司 | Optical display system of AR head display |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN117255183B (en) * | 2023-11-13 | 2024-03-29 | 宜宾市极米光电有限公司 | Projection method and projection apparatus |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09145998A (en) * | 1995-11-20 | 1997-06-06 | Nec Corp | Projection lens and liquid crystal projector using the same |
| CN107741625A (en) * | 2017-10-12 | 2018-02-27 | 深圳市特莱斯光学有限公司 | A kind of low-cost and high-performance drive recorder camera lens |
| CN112147754A (en) * | 2019-06-28 | 2020-12-29 | 宁波舜宇车载光学技术有限公司 | Optical lens and electronic device |
| CN113359279A (en) * | 2021-06-16 | 2021-09-07 | 天津欧菲光电有限公司 | Optical lens assembly, lens module and electronic equipment |
| WO2021217618A1 (en) * | 2020-04-30 | 2021-11-04 | 天津欧菲光电有限公司 | Optical system, camera module, electronic device, and automobile |
| CN114047613A (en) * | 2021-10-29 | 2022-02-15 | 歌尔光学科技有限公司 | Optical system and projection device |
| WO2022032573A1 (en) * | 2020-08-13 | 2022-02-17 | 欧菲光集团股份有限公司 | Optical system, camera module, electronic device and automobile |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP4416391B2 (en) * | 2002-11-22 | 2010-02-17 | 株式会社リコー | Wide-angle lens, camera and projection display device |
| JP6985647B2 (en) * | 2018-03-22 | 2021-12-22 | コニカミノルタ株式会社 | Optical system, lens unit, and image pickup device |
| CN113009674B (en) * | 2021-03-12 | 2024-02-23 | 宁波舜宇车载光学技术有限公司 | Optical lens and electronic device |
| CN214751068U (en) * | 2021-06-22 | 2021-11-16 | 歌尔股份有限公司 | Projection lens and projection equipment |
-
2022
- 2022-03-31 CN CN202210343057.6A patent/CN114740600A/en active Pending
- 2022-06-28 WO PCT/CN2022/101699 patent/WO2023184752A1/en unknown
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH09145998A (en) * | 1995-11-20 | 1997-06-06 | Nec Corp | Projection lens and liquid crystal projector using the same |
| CN107741625A (en) * | 2017-10-12 | 2018-02-27 | 深圳市特莱斯光学有限公司 | A kind of low-cost and high-performance drive recorder camera lens |
| CN112147754A (en) * | 2019-06-28 | 2020-12-29 | 宁波舜宇车载光学技术有限公司 | Optical lens and electronic device |
| WO2021217618A1 (en) * | 2020-04-30 | 2021-11-04 | 天津欧菲光电有限公司 | Optical system, camera module, electronic device, and automobile |
| WO2022032573A1 (en) * | 2020-08-13 | 2022-02-17 | 欧菲光集团股份有限公司 | Optical system, camera module, electronic device and automobile |
| CN113359279A (en) * | 2021-06-16 | 2021-09-07 | 天津欧菲光电有限公司 | Optical lens assembly, lens module and electronic equipment |
| CN114047613A (en) * | 2021-10-29 | 2022-02-15 | 歌尔光学科技有限公司 | Optical system and projection device |
Non-Patent Citations (1)
| Title |
|---|
| 《摄影大辞典》编委会编: "摄影大辞典", 浙江摄影出版社, pages: 128 * |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116400482A (en) * | 2023-05-26 | 2023-07-07 | 合肥综合性国家科学中心人工智能研究院(安徽省人工智能实验室) | Miniature wide-field objective lens for multispectral imaging |
| CN116643409A (en) * | 2023-07-18 | 2023-08-25 | 沂普光电(天津)有限公司 | Optical display system of AR head display |
| CN116643409B (en) * | 2023-07-18 | 2023-10-20 | 沂普光电(天津)有限公司 | Optical display system of AR head display |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2023184752A1 (en) | 2023-10-05 |
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