Lens and single-chip LCD projector

Abstract

The utility model relates to a lens and a single-chip LCD projector. The lens comprises a first lens, a second lens and a third lens which are sequentially and coaxially arranged in the opposite direction of emergent light of the lens. The first lens is a convex lens, the second lens is a concave lens, and the third lens is a convex lens; the refractive index of the first lens ranges from 1.75 to 1.80, the refractive index of the second lens ranges from 1.60 to 1.70, and the refractive index of the third lens ranges from 1.60 to 1.70; the dispersion coefficient of the first lens is Vd1, 45 < = Vd1 < = 55, the dispersion coefficient of the second lens is Vd2, 28 < = Vd1 < = 35, the dispersion coefficient of the third lens is Vd3, 50 < = Vd3 < = 60. By selecting the refractive indexes of the first lens, the second lens and the third lens and the dispersion system, the imaging definition of the lens is obviously improved after light enters the lens, so that the imaging definition is improved, the actual imaging effect of the lens is improved, and the watching and using experience of a user is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of projectors, in particular to a lens and a single-LCD projector. BACKGROUND

[0002] The single-LCD projector comprises a light source, an LCD panel and a lens. The light source is irradiated onto the LCD panel. Since the LCD panel is light-transmitting, the light of the light source is irradiated out. The light is sequentially passed through the LCD panel and the lens and then projected onto a screen to form an image. However, the imaging clarity of the existing lens is low, and the imaging effect is poor, which leads to a poor user viewing experience. SUMMARY

[0003] Therefore, it is necessary to provide a lens and a single-LCD projector to solve the problem of imaging clarity of the lens.

[0004] A lens, comprising:

[0005] a first lens, a second lens and a third lens which are coaxially arranged in sequence along a direction opposite to an exit light direction of the lens;

[0006] the first lens is a convex lens, the second lens is a concave lens, and the third lens is a convex lens;

[0007] a refractive index range of the first lens is 1.75-1.80, a refractive index range of the second lens is 1.60-1.70, and a refractive index range of the third lens is 1.60-1.70;

[0008] a dispersion coefficient of the first lens is Vd1, 45≤Vd1≤55, a dispersion coefficient of the second lens is Vd2, 28≤Vd1≤35, and a dispersion coefficient of the third lens is Vd3, 50≤Vd3≤60.

[0009] In one of the embodiments, a curvature radius range of an end face of a side of the first lens away from the second lens is 45-50 mm, and a curvature radius range of an end face of a side of the first lens close to the second lens is 200-220 mm;

[0010] a curvature radius range of an end face of a side of the second lens close to the first lens is -100--140 mm, and a curvature radius range of an end face of a side of the second lens close to the third lens is 40-50 mm;

[0011] a curvature radius range of an end face of a side of the third lens close to the second lens is 130-150 mm, and a curvature radius range of an end face of a side of the third lens away from the second lens is -60--80 mm.

[0012] In one embodiment, the central thickness of the first lens is in the range of 6-8mm; the central thickness of the second lens is in the range of 1-3mm;

[0013] the central thickness of the third lens is in the range of 6-8mm.

[0014] In one embodiment, further comprising a diaphragm disposed between the second lens and the third lens, the diaphragm being used to adjust the intensity of the light beam entering the second lens.

[0015] In one embodiment, the central distance between the second lens and the diaphragm is in the range of 10-15mm;

[0016] the central distance between the diaphragm and the third lens is in the range of 0-2mm.

[0017] In one embodiment, the central distance between the first lens and the second lens is in the range of 10-15mm.

[0018] The present application also provides a single-piece LCD projector, comprising a Fresnel lens, an LCD panel, and the lens as described above, the Fresnel lens and the lens being disposed in sequence on the light path of the light emitted by the LCD panel.

[0019] In one embodiment, the lens, the Fresnel lens, and the LCD panel are arranged in sequence and coaxially along the direction of the light emitted by the lens;

[0020] the central distance between the third lens and the Fresnel lens is in the range of 92-102mm;

[0021] the central distance between the Fresnel lens and the LCD panel is in the range of 5-9mm.

[0022] In one embodiment, further comprising a mirror, the mirror being disposed on the light path between the Fresnel lens and the lens and being disposed at an angle with the LCD panel, the mirror being used to make the light passing through the Fresnel lens enter the third lens.

[0023] In one embodiment, the focal length of the Fresnel lens is in the range of 90-100mm; and / or,

[0024] the central thickness of the Fresnel lens is in the range of 1.6-2.0mm.

[0025] The first lens and the third lens are both set as convex lenses, the second lens is set as a concave lens, the refractive index of the first lens is 1.75-1.80, the refractive index of the second lens is 1.60-1.70, and the refractive index of the third lens is 1.60-1.70. The dispersion coefficient of the first lens is 45≤Vd1≤55, the dispersion coefficient of the second lens is 28≤Vd1≤35, and the dispersion coefficient of the third lens is 50≤Vd3≤60. The first lens, the second lens, and the third lens are arranged in the direction opposite to the outgoing light of the lens, and the axes of the first lens, the second lens, and the third lens are coaxial, and the light emitted by the light source of the single-LCD projector passes through the third lens, the second lens, and the first lens in sequence. By selecting the refractive index and the dispersion coefficient of the first lens, the second lens, and the third lens, the imaging clarity of the lens is significantly improved when the light enters the lens, thereby improving the imaging clarity, improving the actual imaging effect of the lens, and improving the user's viewing experience. BRIEF DESCRIPTION OF DRAWINGS

[0026] Figure 1 A first structure diagram of a single-LCD projector is provided for the embodiment one of the application.

[0027] Figure 2 A second structure diagram of a single-LCD projector is provided for the embodiment one of the application.

[0028] Figure 3 A structure diagram of a single-LCD projector is provided for the embodiment two of the application.

[0029] In the drawings:

[0030] 100, first lens;

[0031] 200, second lens;

[0032] 300, third lens;

[0033] 400, diaphragm;

[0034] 500, Fresnel lens;

[0035] 600, LCD panel;

[0036] 700, reflector. DETAILED DESCRIPTION

[0037] In order to make the above objectives, features and advantages of the present application more clear and comprehensible, the specific embodiments of the present application will be described in detail below with reference to the accompanying drawings. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present application. However, the present application can be practiced in a number of different ways beyond the specific embodiments described herein and by one of ordinary skill in the art without departing from the spirit and scope of the present application, and it is therefore intended that all such variations be considered as falling within the scope of the present application. It should be understood that the use of the terms "include", "comprise" or "contain" herein should not be understood as limiting the present application to the features or steps described herein, but rather the use of these terms is intended to cover the presence of the features or steps described herein as well as the presence of other features or steps not described herein.

[0038] In the description of the present application, it should be understood that, if these terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential" and the like appear, these terms indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the purpose of facilitating the description of the present application and simplifying the description, and are not intended to indicate or imply that the device or element referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as a limitation on the present application.

[0039] In addition, if these terms "first", "second" appear, these terms are only for the purpose of description, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the technical features referred to. Therefore, the features defined with "first", "second" can include at least one of the features explicitly or implicitly. In the description of the present application, if the term "a plurality of" appears, the meaning of "a plurality of" is at least two, for example, two, three, etc., unless otherwise specifically limited.

[0040] In the present application, unless otherwise specifically defined and limited, if the terms "mount", "connect", "connect", "fix" and the like appear, these terms should be interpreted broadly. For example, it can be fixedly connected, or it can be detachably connected, or it can be integrated; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the internal communication or interaction relationship of two elements, unless otherwise specifically limited. For those of ordinary skill in the art, the specific meaning of the above terms in the present application can be understood according to the specific circumstances.

[0041] In the present application, unless specifically defined and limited otherwise, if there is a description of a first feature on or above or below a second feature, it can mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature can be above or above or above the second feature, or it can only mean that the first feature is higher in horizontal height than the second feature. The first feature can be below or below or below the second feature, or it can only mean that the first feature is lower in horizontal height than the second feature.

[0042] It should be noted that if an element is referred to as being "fixed" or "set" on another element, it can be directly on the other element or there can be an intermediate element. If an element is considered to be "connected" to another element, it can be directly connected to the other element or there can be an intermediate element. If present, the terms "vertical", "horizontal", "up", "down", "left", "right" and similar expressions used in the present application are only for illustrative purposes and do not represent the only implementation.

[0043] The present application provides a lens, such as Figure 1 and Figure 2 The lens includes, in order along the direction of the outgoing light of the lens, a first lens 100, a second lens 200, and a third lens 300; the first lens 100 is a convex lens, the second lens 200 is a concave lens, and the third lens 300 is a convex lens; the refractive index of the first lens 100 ranges from 1.75 to 1.80, the refractive index of the second lens 200 ranges from 1.60 to 1.70, and the refractive index of the third lens 300 ranges from 1.60 to 1.70; the dispersion coefficient of the first lens 100 is Vd1, 45≤Vd1≤55, the dispersion coefficient of the second lens 200 is Vd2, 28≤Vd1≤35, and the dispersion coefficient of the third lens 300 is Vd3, 50≤Vd3≤60.

[0044] The first lens 100 and the third lens 300 are both convex lenses, the second lens 200 is a concave lens, the refractive index of the first lens 100 is 1.75-1.80, the refractive index of the second lens 200 is 1.60-1.70, and the refractive index of the third lens 300 is 1.60-1.70. The dispersion coefficient of the first lens 100 is 45≤Vd1≤55, the dispersion coefficient of the second lens 200 is 28≤Vd1≤35, and the dispersion coefficient of the third lens 300 is 50≤Vd3≤60. The first lens 100, the second lens 200, and the third lens 300 are arranged in the direction opposite to the exit light of the lens, and the axes of the first lens 100, the second lens 200, and the third lens 300 are coaxial. The light emitted by the light source of the single-chip LCD projector passes through the third lens 300, the second lens 200, and the first lens 100 in sequence. By selecting the refractive index and the dispersion coefficient of the first lens 100, the second lens 200, and the third lens 300, the imaging clarity of the lens is significantly improved when the light enters the lens, thereby improving the imaging clarity, improving the actual imaging effect of the lens, and improving the user's viewing experience.

[0045] It should be noted that the first lens 100 is made of a medium-dispersion glass material, wherein the medium dispersion refers to a dispersion coefficient in the range of 45-55. The second lens 200 is a concave lens made of a high-dispersion glass material, wherein the high dispersion refers to a dispersion coefficient in the range of 28-35. The third lens 300 is made of a medium-low dispersion glass material, wherein the medium-low dispersion refers to a dispersion coefficient in the range of 50-60.

[0046] In some embodiments, the radius of curvature of the end surface of the side of the first lens 100 away from the second lens 200 is in the range of 45-50 mm, the radius of curvature of the end surface of the side of the first lens 100 close to the second lens 200 is in the range of 200-220 mm; the radius of curvature of the end surface of the side of the second lens 200 close to the first lens 100 is in the range of -100 to -140 mm, and the radius of curvature of the end surface of the side of the second lens 200 close to the third lens 300 is in the range of 40-50 mm; the radius of curvature of the end surface of the side of the third lens 300 close to the second lens 200 is in the range of 130-150 mm, and the radius of curvature of the end surface of the side of the third lens 300 away from the second lens 200 is in the range of -60 to -80 mm. By selecting the radius of curvature of each side of the first lens 100, the second lens 200, and the third lens 300, a lens suitable for production and processing is selected.

[0047] In some embodiments, the central thickness of the first lens 100 ranges from 6 to 8 mm; the central thickness of the second lens 200 ranges from 1 to 3 mm; and the central thickness of the third lens 300 ranges from 6 to 8 mm. By selecting the central thickness of the first lens 100, the second lens 200, and the third lens 300, the production cost can be reduced and the clarity of the lens can be improved.

[0048] In some embodiments, as shown in FIG. 1, the lens further comprises a diaphragm 400 disposed between the second lens 200 and the third lens 300, the diaphragm 400 being configured to adjust the intensity of the light beam entering the second lens 200. Figure 1 and Figure 2 In some embodiments, the diaphragm 400 is disposed between the second lens 200 and the third lens 300, and the diaphragm 400 is configured to adjust the intensity of the light beam entering the second lens 200. By disposing the diaphragm 400 between the second lens 200 and the third lens 300, the diaphragm 400 can control the amount of light entering the second lens 200 and adjust the intensity of the light beam entering the second lens 200, thereby further improving the clarity of the lens.

[0049] In some embodiments, the central distance between the second lens 200 and the diaphragm 400 ranges from 10 to 12 mm. By limiting the central distance between the second lens 200 and the diaphragm 400, the size and the clarity of the lens can be limited.

[0050] In some embodiments, the central distance between the diaphragm 400 and the third lens 300 ranges from 0 to 2 mm. By limiting the central distance between the diaphragm 400 and the third lens 300, the size and the clarity of the lens can be limited.

[0051] In some embodiments, the central distance between the second lens 200 and the diaphragm 400 ranges from 10 to 12 mm, and the central distance between the diaphragm 400 and the third lens 300 ranges from 0 to 2 mm. By limiting the central distance between the second lens 200 and the diaphragm 400 and limiting the central distance between the diaphragm 400 and the third lens 300.

[0052] In some embodiments, the central distance between the first lens 100 and the second lens 200 ranges from 10 to 15 mm. By limiting the central distance between the first lens 100 and the second lens 200, the clarity of the lens can be improved.

[0053] It should be noted that the center distance between the first lens 100 and the second lens 200, that is, the distance between the axis of the first lens 100 and the axis of the second lens 200 along the light path direction, can be determined by those skilled in the art in the field of lens technology, so that the distance between the two lenses can be determined. Similarly, the center distance between the second lens 200 and the diaphragm 400, and the center distance between the third lens 300 and the diaphragm 400 can also be determined.

[0054] The application also provides a single-chip LCD projector, as shown in the accompanying drawings, comprising a Fresnel lens 500, an LCD panel 600, and the lens described above, the Fresnel lens 500 and the lens being arranged in sequence on the light path of the light emitted by the LCD panel 600. The light emitted by the light source of the single-chip LCD projector passes through the LCD panel 600, the Fresnel lens 500, the third lens 300, the second lens 200, and the first lens 100 in sequence, and then forms an image. Figures 1 to 3

[0055] In some embodiments, as shown in the accompanying drawings, the lens, the Fresnel lens 500, and the LCD panel 600 are arranged in sequence and coaxially along the direction opposite to the light emitted by the lens, that is, the first lens 100, the second lens 200, the third lens 300, the Fresnel lens 500, and the LCD panel 600 are arranged in sequence along the direction opposite to the light emitted by the lens, and the axes of the first lens 100, the second lens 200, the third lens 300, the Fresnel lens 500, and the LCD panel 600 are coaxial. Figure 1 Figure 2

[0056] In some embodiments, when the lens, the Fresnel lens 500, and the LCD panel 600 are coaxially arranged, the center distance between the third lens 300 and the Fresnel lens 500 ranges from 92 mm to 102 mm.

[0057] In some embodiments, when the lens, the Fresnel lens 500, and the LCD panel 600 are coaxially arranged, the center distance between the Fresnel lens 500 and the LCD panel 600 ranges from 5 mm to 9 mm.

[0058] In some embodiments, when the lens, the Fresnel lens 500, and the LCD panel 600 are coaxially arranged, the center distance between the third lens 300 and the Fresnel lens 500 ranges from 92 mm to 102 mm, and the center distance between the Fresnel lens 500 and the LCD panel 600 ranges from 5 mm to 9 mm. By limiting the center distance between the lens, the Fresnel lens 500, and the LCD panel 600, the imaging clarity of the single-chip LCD projector is further adjusted.

[0059] ​​​In some embodiments, the focal length of the Fresnel lens 500 ranges from 90 to 100 mm.

[0060] In some embodiments, the center thickness of the Fresnel lens 500 ranges from 1.6 to 2.0 mm.

[0061] In some embodiments, the focal length of the Fresnel lens 500 is in the range of 90 to 100 mm, and the center thickness of the Fresnel lens 500 is in the range of 1.6 to 2.0 mm. By limiting the focal length range and the center thickness range of the Fresnel lens 500, the imaging clarity of the monolithic LCD projector is further adjusted.

[0062] In some embodiments, such as Figure 3 As shown, the single-panel LCD projector also includes a reflector 700, which is disposed in the optical path between the Fresnel lens 500 and the lens and is angled to the LCD panel 600. The reflector 700 is used to direct the light passing through the Fresnel lens 500 into the third lens 300. The light emitted by the light source of the single-panel LCD projector passes sequentially through the LCD panel 600, the Fresnel lens 500, the reflector 700, the third lens 300, the second lens 200, and the first lens 100 to form an image.

[0063] Specifically, such as Figure 3 As shown, the LCD panel 600 and the lens axis form an angle, the LCD panel 600 forms an angle with the Fresnel lens 500, and the LCD panel 600 forms an angle with the reflector 700.

[0064] Because the lens design parameters are related to the size and resolution of the selected LCD screen, this application uses a 4-inch projection LCD screen with a physical resolution of 1920*1080, a single pixel size of 46.14µm, and a corresponding resolution of 10.8 line pairs per millimeter. After determining the lens's refractive index, dispersion coefficient, radius of curvature, center thickness, and center distance, and determining the distances between the Fresnel lens 500 of the single-chip LCD projector and the lens and LCD panel 600, as well as the focal length and center thickness of the Fresnel lens 500, simulation analysis using dedicated lens design software was conducted. The results show that the LCD projector provided in this application can achieve the following imaging indicators:

[0065] (1) The RMS radius of the imaging spot in each field of view (the smaller this value is, the better the resolution of the lens) is smaller than the size of one pixel of the LCD screen, which meets the design requirements of DLP lens.

[0066] (2) The MTF value at 10.8 line pairs per millimeter is greater than 0.3 (the higher this value, the better the resolution of the lens), which is far better than the MTF level of existing lenses on the market, which is less than 0.2.

[0067] (3) The relative illumination of the lens at the maximum field of view is greater than 60%, meeting the requirements of DLP lens design.

[0068] (4) The field curvature within the full field of view is less than 2mm, and the distortion is less than 2%, meeting the requirements of DLP lens design.

[0069] (5) The axial chromatic aberration within the full field of view is less than 10um, which is much better than the design requirement of DLP lens that is less than one pixel.

[0070] Compared with the existing 4-inch LCD screen 1080p projection products on the market, the design uses three spherical glass lenses to greatly improve the spot size and MTF value of the optical-mechanical lens imaging under the conditions of Fnumber 2.8-3.0 and projection ratio less than 1.4, greatly improving the imaging clarity and use viewing experience of single-piece LCD projection products, thereby greatly improving the market competitiveness of single-piece LCD projection products.

[0071] The technical features of the above-described embodiments can be combined arbitrarily. To make the description concise, all possible combinations of the technical features in the above-described embodiments are not described, but as long as the combinations of the technical features do not exist, they should be considered as the scope of the present disclosure.

[0072] The above-described embodiments only express several implementation manners of the present application, and the description is more specific and detailed, but it should not be understood as a limitation on the scope of the patent application. It should be pointed out that for ordinary skilled persons in the art, some modifications and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the patent of the present application should be subject to the appended claims.

Claims

1. A lens characterized by comprising: The lens comprises: a first lens (100), a second lens (200) and a third lens (300) are coaxially arranged in sequence along the direction of the outgoing light of the lens; the first lens (100) is a convex lens, the second lens (200) is a concave lens, and the third lens (300) is a convex lens; the refractive index of the first lens (100) ranges from 1.75 to 1.80, the refractive index of the second lens (200) ranges from 1.60 to 1.70, and the refractive index of the third lens (300) ranges from 1.60 to 1.70; the dispersion coefficient of the first lens (100) is Vd1, 45≤Vd1≤55, the dispersion coefficient of the second lens (200) is Vd2, 28≤Vd1≤35, and the dispersion coefficient of the third lens (300) is Vd3, 50≤Vd3≤60.

2. The lens according to claim 1, characterized in that, the radius of curvature of the end face of the side of the first lens (100) away from the second lens (200) ranges from 45 to 50 mm, and the radius of curvature of the end face of the side of the first lens (100) close to the second lens (200) ranges from 200 to 220 mm; the radius of curvature of the end face of the side of the second lens (200) close to the first lens (100) ranges from -100 to -140 mm, and the radius of curvature of the end face of the side of the second lens (200) close to the third lens (300) ranges from 40 to 50 mm; the radius of curvature of the end face of the side of the third lens (300) close to the second lens (200) ranges from 130 to 150 mm, and the radius of curvature of the end face of the side of the third lens (300) away from the second lens (200) ranges from -60 to -80 mm.

3. The lens of claim 1, wherein the central thickness of the first lens (100) ranges from 6 to 8 mm; the central thickness of the second lens (200) ranges from 1 to 3 mm; the central thickness of the third lens (300) ranges from 6 to 8 mm.

4. The lens of claim 1, wherein a diaphragm (400) is further arranged between the second lens (200) and the third lens (300), and the diaphragm (400) is used for adjusting the intensity of the light beam entering the second lens (200).

5. The lens of claim 4, wherein, the central distance between the second lens (200) and the diaphragm (400) ranges from 10 to 15 mm, and the central distance between the diaphragm (400) and the third lens (300) ranges from 0 to 2 mm.

6. The lens according to any one of claims 1 to 5, characterized in that the central distance between the first lens (100) and the second lens (200) is 10-15 mm.

7. A monolithic LCD projector characterized by comprising: a Fresnel lens (500), an LCD panel (600) and the lens of any one of claims 1-6 are sequentially arranged in the light path of the outgoing light of the LCD panel (600).

8. The single panel LCD projector of claim 7, wherein, the lens, the Fresnel lens (500) and the LCD panel (600) are sequentially arranged and coaxially arranged along the direction of the outgoing light of the lens; The center distance between the third lens (300) and the Fresnel lens (500) ranges from 92 to 102 mm; The center distance between the Fresnel lens (500) and the LCD panel (600) ranges from 5 to 9 mm.

9. The single panel LCD projector of claim 7, wherein, A reflector (700) is further included, which is arranged on the light path between the Fresnel lens (500) and the lens and is arranged at an angle with the LCD panel (600), and is used for making the light passing through the Fresnel lens (500) enter the third lens (300).

10. The single panel LCD projector according to any one of claims 7-9, wherein, The focal length of the Fresnel lens (500) ranges from 90 to 100 mm; and / or, The center thickness of the Fresnel lens (500) ranges from 1.6 to 2.0 mm.

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