WO2019119728A1 - 投影镜头 - Google Patents

投影镜头 Download PDF

Info

Publication number
WO2019119728A1
WO2019119728A1 PCT/CN2018/088685 CN2018088685W WO2019119728A1 WO 2019119728 A1 WO2019119728 A1 WO 2019119728A1 CN 2018088685 W CN2018088685 W CN 2018088685W WO 2019119728 A1 WO2019119728 A1 WO 2019119728A1
Authority
WO
WIPO (PCT)
Prior art keywords
lens
projection lens
projection
optical axis
focal length
Prior art date
Application number
PCT/CN2018/088685
Other languages
English (en)
French (fr)
Inventor
黄林
Original Assignee
浙江舜宇光学有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority claimed from CN201721780862.6U external-priority patent/CN207516712U/zh
Priority claimed from CN201711375247.1A external-priority patent/CN107861317B/zh
Application filed by 浙江舜宇光学有限公司 filed Critical 浙江舜宇光学有限公司
Priority to US16/293,103 priority Critical patent/US11143843B2/en
Publication of WO2019119728A1 publication Critical patent/WO2019119728A1/zh

Links

Images

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B13/00—Optical objectives specially designed for the purposes specified below
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B9/00—Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or -
    • G02B9/04—Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or - having two components only
    • G02B9/06—Optical objectives characterised both by the number of the components and their arrangements according to their sign, i.e. + or - having two components only two + components
    • 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

Definitions

  • the present application relates to a projection lens, and more particularly, to a projection lens including two lenses.
  • Conventional projection lenses for imaging generally eliminate various aberrations and increase resolution by increasing the number of lenses.
  • increasing the number of lenses causes an increase in the total optical length of the projection lens, which is disadvantageous for miniaturization of the lens.
  • the general large-angle projection lens also has many problems such as large distortion and poor image quality, and cannot be matched with the optical diffraction element (DOE) to accurately realize the redistribution of the projection beam on the target object.
  • DOE optical diffraction element
  • the present application provides a projection lens that can be adapted for use in a portable electronic product that can at least solve or partially address at least one of the above disadvantages of the prior art.
  • One aspect of the present application provides a projection lens that sequentially includes, from the source side to the imaging side, along the optical axis: a first lens having positive power; and a second lens having positive power.
  • a first lens having positive power at least one of the first lens and the second lens may be a lens made of glass; and the total effective focal length f of the projection lens and the effective focal length f2 of the second lens may satisfy 1 ⁇ f/f2 ⁇ 1.5.
  • the image source side surface of the first lens may be a convex surface
  • the image side surface may be a concave surface
  • the image source side surface of the second lens may be a concave surface
  • the image forming side surface may be a convex surface
  • a smaller value TCE MIN of the thermal expansion coefficient of the first lens and the thermal expansion coefficient of the second lens may satisfy TCE MIN ⁇ 15 ⁇ 10 -6 /°C.
  • the maximum half angle of view HFOV of the projection lens may satisfy 0 ⁇ TAN(HFOV) ⁇ 0.35.
  • the light transmittance of the projection lens may be greater than 85% in the light wave band of 800 nm to 1000 nm.
  • the center thickness CT1 of the first lens on the optical axis and the center thickness CT2 of the second lens on the optical axis may satisfy 0.6 ⁇ CT1/CT2 ⁇ 1.2.
  • the center thickness CT1 of the first lens on the optical axis, the center thickness CT2 of the second lens on the optical axis, and the optical total length TTL of the projection lens can satisfy 0.4 ⁇ (CT1+CT2)/TTL ⁇ 0.8 .
  • the radius of curvature R1 of the image source side surface of the first lens and the radius of curvature R4 of the image side surface of the second lens may satisfy -1.2 ⁇ R1/R4 ⁇ -0.8.
  • the effective half aperture DT11 of the image source side surface of the first lens and the effective half aperture DT22 of the imaging side surface of the second lens may satisfy 0.7 ⁇ DT11 / DT22 ⁇ 1.
  • the total effective focal length f of the projection lens, the effective focal length f1 of the first lens, and the effective focal length f2 of the second lens may satisfy 0.5 ⁇ f / (f1 + f2) ⁇ 0.8.
  • One aspect of the present application provides a projection lens that includes, in order from the source side to the imaging side, along the optical axis, a first lens having a positive power, and a second lens having a positive power.
  • the first lens and the second lens may be a lens made of glass; and the total effective focal length f of the projection lens, the effective focal length f1 of the first lens, and the effective focal length f2 of the second lens may satisfy 0.5 ⁇ f /(f1+f2) ⁇ 0.8.
  • One aspect of the present application provides a projection lens that includes, in order from the source side to the imaging side, along the optical axis, a first lens having a positive power, and a second lens having a positive power.
  • the first lens and the second lens may be a lens made of glass; and the effective half diameter DT11 of the image source side surface of the first lens and the effective half diameter DT22 of the imaging side surface of the second lens may satisfy 0.7 ⁇ DT11 / DT22 ⁇ 1.
  • a plurality of (for example, two) lenses are used, and the above-mentioned lens materials are rationally selected, and the power, the surface shape of each lens, the center thickness of each lens, and the on-axis spacing between the lenses are appropriately allocated.
  • the projection lens has at least one advantageous effect of high performance, miniaturization, low temperature drift, high image quality, and the like, and the above projection lens can be used with an optical diffraction element (DOE).
  • DOE optical diffraction element
  • FIG. 1 is a schematic structural view of a projection lens according to Embodiment 1 of the present application.
  • FIG. 3 is a schematic structural view of a projection lens according to Embodiment 2 of the present application.
  • FIG. 5 is a schematic structural diagram of a projection lens according to Embodiment 3 of the present application.
  • FIG. 7 is a schematic structural diagram of a projection lens according to Embodiment 4 of the present application.
  • FIG. 8 is a view showing a distortion curve of the projection lens of Embodiment 4.
  • FIG. 9 is a schematic structural diagram of a projection lens according to Embodiment 5 of the present application.
  • FIG. 10 is a view showing a distortion curve of the projection lens of Embodiment 5.
  • Figure 11 shows a schematic view of a projection lens in accordance with the present application for use with a diffractive element.
  • first, second, etc. are used to distinguish one feature from another, and do not represent any limitation of the feature.
  • first lens discussed below may also be referred to as a second lens
  • second lens may also be referred to as a first lens, without departing from the teachings of the present application.
  • the thickness, size, and shape of the lens have been somewhat exaggerated for convenience of explanation.
  • the spherical or aspherical shape shown in the drawings is shown by way of example. That is, the shape of the spherical surface or the aspherical surface is not limited to the spherical or aspherical shape shown in the drawings.
  • the drawings are only examples and are not to scale.
  • a paraxial region refers to a region near the optical axis. If the surface of the lens is convex and the position of the convex surface is not defined, it indicates that the surface of the lens is convex at least in the paraxial region; if the surface of the lens is concave and the position of the concave surface is not defined, it indicates that the surface of the lens is at least in the paraxial region. Concave.
  • the surface closest to the image source side in each lens is referred to as an image source side surface, and the surface closest to the image side in each lens is referred to as an image side surface.
  • a projection lens according to an exemplary embodiment of the present application may include, for example, two lenses having power, that is, a first lens and a second lens.
  • the two lenses are sequentially arranged from the source side to the image side along the optical axis.
  • the first lens may have positive power and the second lens may have positive power.
  • Reasonable distribution of the power and shape of each lens is beneficial to improve the performance of the projection lens; at the same time, it is beneficial to reduce the total length of the lens and ensure the miniaturization of the lens.
  • the image source side surface of the first lens may be a convex surface
  • the image forming side surface may be a concave surface
  • the image source side surface of the second lens may be a concave surface
  • the image forming side surface may be a convex surface.
  • the projection lens of the present application may satisfy the conditional expression TCE MIN ⁇ 15 ⁇ 10 -6 /° C, wherein TCE MIN is the smaller of the thermal expansion coefficient of the first lens and the thermal expansion coefficient of the second lens. . More specifically, TCE MIN can further satisfy 0.00 ⁇ 10 -6 / ° C ⁇ TCE MIN ⁇ 9.50 ⁇ 10 -6 / ° C. At least one of the first lens and the second lens is a glass-made lens. Reasonable use of glass lenses helps to reduce temperature drift.
  • the projection lens of the present application may satisfy the conditional expression 0 ⁇ TAN(HFOV) ⁇ 0.35, where HFOV is the maximum half angle of view of the projection lens. More specifically, HFOV may further satisfy 0.1 ⁇ TAN (HFOV) ⁇ 0.2, for example, 0.15 ⁇ TAN (HFOV) ⁇ 0.16. It is beneficial to reduce the size effect of the image source on the image side and improve the optical performance of the projection lens.
  • the projection lens of the present application may satisfy the conditional expression 0.6 ⁇ CT1/CT2 ⁇ 1.2, where CT1 is the center thickness of the first lens on the optical axis, and CT2 is the center of the second lens on the optical axis. thickness. More specifically, CT1 and CT2 can further satisfy 0.61 ⁇ CT1/CT2 ⁇ 1.06. Reasonably distributing the center thickness of the first lens and the second lens is advantageous for ensuring that the lens has a short total length and achieving miniaturization characteristics.
  • the projection lens of the present application may satisfy the conditional expression 0.4 ⁇ (CT1+CT2)/TTL ⁇ 0.8, where CT1 is the center thickness of the first lens on the optical axis, and CT2 is the second lens in the light.
  • the center thickness on the shaft, TTL is the total optical length of the projection lens (i.e., the distance from the source to the center of the imaging side surface of the second lens on the optical axis).
  • CT1, CT2 and TTL can further satisfy 0.50 ⁇ (CT1 + CT2) / TTL ⁇ 0.76.
  • the conditional formula 0.4 ⁇ (CT1+CT2)/TTL ⁇ 0.8 is satisfied, which is advantageous for miniaturization of the lens.
  • the projection lens of the present application may satisfy the conditional expression -1.2 ⁇ R1/R4 ⁇ -0.8, where R1 is the radius of curvature of the image source side surface of the first lens, and R4 is the imaging side of the second lens The radius of curvature of the surface. More specifically, R1 and R4 may further satisfy -1.15 ⁇ R1/R4 ⁇ -0.82. Reasonably distributing the radius of curvature of the first lens and the second lens is advantageous for reducing the sensitivity of the lens.
  • the projection lens of the present application may satisfy the conditional expression 0.7 ⁇ DT11/DT22 ⁇ 1, where DT11 is the effective half aperture of the image source side surface of the first lens, and DT22 is the imaging side surface of the second lens. Effective half-caliber. More specifically, DT11 and DT22 can further satisfy 0.7 ⁇ DT11 / DT22 ⁇ 0.9, for example, 0.78 ⁇ DT11 / DT22 ⁇ 0.83. Satisfying the conditional expression 0.7 ⁇ DT11/DT22 ⁇ 1 is beneficial to reducing the size effect of the image source on the image side and improving the optical performance of the projection lens. Reasonable allocation of DT11 and DT22 is also beneficial to avoid degradation of imaging quality due to excessive bending of light.
  • the projection lens of the present application has a light transmittance of greater than 85% in a light wave band of about 800 nm to about 1000 nm. Such a setting is advantageous for improving the transmittance of near-infrared light through the projection lens, thereby obtaining a higher-intensity near-infrared projection image.
  • the projection lens of the present application may satisfy conditional expression ⁇ f/f2 ⁇ 1.5, where f is the total effective focal length of the projection lens and f2 is the effective focal length of the second lens. More specifically, f and f2 can further satisfy 1.11 ⁇ f / f2 ⁇ 1.48. Reasonably distributing the power of the second lens is beneficial to reducing the temperature drift and improving the optical performance of the lens.
  • the projection lens of the present application may satisfy the conditional expression 0.5 ⁇ f/(f1+f2) ⁇ 0.8, where f is the total effective focal length of the projection lens, f1 is the effective focal length of the first lens, and f2 is The effective focal length of the second lens. More specifically, f, f1 and f2 can further satisfy 0.55 ⁇ f / (f1 + f2) ⁇ 0.66. Reasonably distributing the power of the first lens and the second lens is advantageous for achieving high performance of the lens.
  • the above projection lens may further include at least one aperture to enhance the imaging quality of the lens.
  • the aperture can be placed at any position as desired, for example, the aperture can be disposed between the second lens and the imaging side.
  • the above projection lens may further include other well-known optical projection elements such as prisms, field mirrors and the like.
  • the main difference of the projection lens is that the light of the general imaging lens forms an image surface from the object side to the imaging side; while the light of the general projection lens is enlarged from the image side to the imaging side, the image plane is enlarged and projected to the projection surface. .
  • the amount of light entering the projection lens is controlled by the object numerical aperture and the lens aperture.
  • the projection lens according to the above embodiment of the present application may employ, for example, two lenses, by reasonably selecting the material of the lens and rationally distributing the power, the surface shape, the center thickness of each lens, and the on-axis spacing between the lenses. In this way, the projection lens has the advantages of high performance, miniaturization, low temperature drift, high image quality and the like.
  • the projection lens according to the present application can be applied to the field of depth detection as a speckle projection lens.
  • a speckle projection lens As shown in FIG. 11, when the target object in space is depth-detected using the projection lens of the present application, light emitted by an infrared laser diode (LD) or a vertical cavity surface emitting laser (VCSEL) is first amplified by a projection lens. Then, it passes through the optical diffraction element (DOE) and then projects toward the target object. After the projection beam passes through the optical diffraction element (DOE), the redistribution of the projected image on the target object can be achieved. Thereafter, the image information projected onto the target object is captured by any known imaging lens (not shown), and the three-dimensional image having the target object position depth information can be calculated.
  • the projection lens according to the present application can be used in conjunction with an optical diffraction element (DOE) to accurately achieve redistribution of the projected beam onto the target object.
  • DOE optical diffraction element
  • At least one of the mirror faces of each lens is an aspherical mirror.
  • the aspherical lens is characterized by a continuous change in curvature from the center of the lens to the periphery of the lens. Unlike a spherical lens having a constant curvature from the center of the lens to the periphery of the lens, the aspherical lens has better curvature radius characteristics, and has the advantages of improving distortion and improving astigmatic aberration. With an aspherical lens, the aberrations that occur during imaging can be eliminated as much as possible, improving image quality.
  • the various results and advantages described in this specification can be obtained without varying the number of lenses that make up the projection lens without departing from the technical solutions claimed herein.
  • the projection lens is not limited to including two lenses.
  • the projection lens can also include other numbers of lenses if desired.
  • FIG. 1 is a block diagram showing the structure of a projection lens according to Embodiment 1 of the present application.
  • a projection lens sequentially includes, along the optical axis, from an image source side to an imaging side: a first lens E1, a second lens E2, and a stop STO.
  • the first lens E1 has a positive power
  • the image side surface S1 is a convex surface
  • the imaging side surface S2 is a concave surface
  • the second lens E2 has a positive power
  • the image side surface S3 is a concave surface
  • the imaging side surface S4 is a convex surface.
  • the light transmittance of the projection lens is greater than 85%.
  • Light from the image source sequentially passes through the respective surfaces S1 to S4 and is finally imaged on a projection surface (not shown) such as a projection screen.
  • Table 1 shows the surface type, radius of curvature, thickness, material, and conical coefficient of each lens of the projection lens of Example 1, in which the unit of curvature radius and thickness are both millimeters (mm).
  • each aspherical lens can be defined by, but not limited to, the following aspherical formula:
  • x is the distance of the aspherical surface at height h from the optical axis, and the distance from the aspherical vertex is high;
  • k is the conic coefficient (given in Table 1);
  • Ai is the correction coefficient of the a-th order of the aspherical surface.
  • Table 2 gives the high order term coefficients A 4 , A 6 , A 8 , A 10 , A 12 , A 14 and A 16 which can be used for the respective aspherical mirror faces S1 - S4 in the embodiment 1.
  • Table 3 gives the total effective focal length f of the projection lens in Embodiment 1, the effective focal lengths f1 and f2 of the respective lenses, and the optical total length TTL of the projection lens (i.e., from the image source OBJ to the imaging side surface S4 of the second lens E2).
  • the projection lens in Embodiment 1 satisfies:
  • TAN(HFOV) 0.15, where HFOV is the maximum half angle of view of the projection lens;
  • CT1/CT2 0.61, wherein CT1 is the center thickness of the first lens E1 on the optical axis, and CT2 is the center thickness of the second lens E2 on the optical axis;
  • CT1+CT2/TTL 0.50, where CT1 is the center thickness of the first lens E1 on the optical axis, CT2 is the center thickness of the second lens E2 on the optical axis, and TTL is the optical total length of the projection lens;
  • R1/R4 -0.83, where R1 is the radius of curvature of the image source side surface S1 of the first lens E1, and R4 is the radius of curvature of the image side surface S4 of the second lens E2;
  • DT11 / DT22 0.80, wherein DT11 is the effective half diameter of the image source side surface S1 of the first lens E1, and DT22 is the effective half diameter of the imaging side surface S4 of the second lens E2;
  • f/f2 1.22, where f is the total effective focal length of the projection lens, and f2 is the effective focal length of the second lens E2;
  • f / (f1 + f2) 0.55, where f is the total effective focal length of the projection lens, f1 is the effective focal length of the first lens E1, and f2 is the effective focal length of the second lens E2;
  • TCE MIN 0.00 ⁇ 10 -6 / ° C, where TCE MIN is a smaller of the thermal expansion coefficient of the first lens E1 and the thermal expansion coefficient of the second lens E2.
  • Fig. 2 is a view showing a distortion curve of the projection lens of Embodiment 1, which shows distortion magnitude values in the case of different viewing angles. According to FIG. 2, the projection lens given in Embodiment 1 can achieve good image quality.
  • FIG. 3 is a schematic structural view of a projection lens according to Embodiment 2 of the present application.
  • a projection lens sequentially includes, along the optical axis, from the image source side to the imaging side: a first lens E1, a second lens E2, and a stop STO.
  • the first lens E1 has a positive power
  • the image side surface S1 is a convex surface
  • the imaging side surface S2 is a concave surface
  • the second lens E2 has a positive power
  • the image side surface S3 is a concave surface
  • the imaging side surface S4 is a convex surface.
  • the light transmittance of the projection lens is greater than 85%.
  • Light from the image source sequentially passes through the respective surfaces S1 to S4 and is finally imaged on a projection surface (not shown) such as a projection screen.
  • Table 4 shows the surface type, the radius of curvature, the thickness, the material, and the conical coefficient of each lens of the projection lens of Example 2, wherein the unit of the radius of curvature and the thickness are each mm (mm).
  • the image source side surface S1 and the image forming side surface S2 of the first lens E1 and the image source side surface S3 and the image forming side surface S4 of the second lens E2 are both aspherical.
  • Table 5 shows the high order coefficient which can be used for each aspherical mirror in Embodiment 2, wherein each aspherical surface type can be defined by the formula (1) given in the above Embodiment 1.
  • Table 6 gives the total effective focal length f of the projection lens in Embodiment 2, the effective focal lengths f1 and f2 of each lens, the optical total length TTL of the projection lens, the maximum half angle of view HFOV of the projection lens, and the object-side numerical aperture of the projection lens. NA.
  • Fig. 4 is a view showing a distortion curve of the projection lens of Embodiment 2, which shows distortion magnitude values in the case of different viewing angles. As can be seen from FIG. 4, the projection lens given in Embodiment 2 can achieve good image quality.
  • FIG. 5 is a schematic structural view of a projection lens according to Embodiment 3 of the present application.
  • a projection lens sequentially includes, along the optical axis, from the image source side to the imaging side: a first lens E1, a second lens E2, and a stop STO.
  • the first lens E1 has a positive power
  • the image side surface S1 is a convex surface
  • the imaging side surface S2 is a concave surface
  • the second lens E2 has a positive power
  • the image side surface S3 is a concave surface
  • the imaging side surface S4 is a convex surface.
  • the light transmittance of the projection lens is greater than 85%.
  • Light from the image source sequentially passes through the respective surfaces S1 to S4 and is finally imaged on a projection surface (not shown) such as a projection screen.
  • Table 7 shows the surface type, the radius of curvature, the thickness, the material, and the conical coefficient of each lens of the projection lens of Example 3, wherein the units of the radius of curvature and the thickness are each mm (mm).
  • the image source side surface S1 and the image forming side surface S2 of the first lens E1 and the image source side surface S3 and the image forming side surface S4 of the second lens E2 are both aspherical.
  • Table 8 shows the high order term coefficients which can be used for the respective aspherical mirrors in Embodiment 3, wherein each aspherical surface type can be defined by the formula (1) given in the above Embodiment 1.
  • Table 9 gives the total effective focal length f of the projection lens in Embodiment 3, the effective focal lengths f1 and f2 of each lens, the optical total length TTL of the projection lens, the maximum half angle of view HFOV of the projection lens, and the object-side numerical aperture of the projection lens. NA.
  • Fig. 6 is a view showing a distortion curve of the projection lens of Embodiment 3, which shows distortion magnitude values in the case of different viewing angles. As can be seen from Fig. 6, the projection lens given in Embodiment 3 can achieve good image quality.
  • FIG. 7 is a block diagram showing the structure of a projection lens according to Embodiment 4 of the present application.
  • a projection lens sequentially includes, along the optical axis, from the image source side to the imaging side: a first lens E1, a second lens E2, and a stop STO.
  • the first lens E1 has a positive power
  • the image side surface S1 is a convex surface
  • the imaging side surface S2 is a concave surface
  • the second lens E2 has a positive power
  • the image side surface S3 is a concave surface
  • the imaging side surface S4 is a convex surface.
  • the light transmittance of the projection lens is greater than 85%.
  • Light from the image source sequentially passes through the respective surfaces S1 to S4 and is finally imaged on a projection surface (not shown) such as a projection screen.
  • Table 10 shows the surface type, the radius of curvature, the thickness, the material, and the conical coefficient of each lens of the projection lens of Example 4, wherein the unit of the radius of curvature and the thickness are each mm (mm).
  • the image source side surface S1 and the image forming side surface S2 of the first lens E1 and the image source side surface S3 and the image forming side surface S4 of the second lens E2 are both aspherical.
  • Table 11 shows the high order coefficient which can be used for each aspherical mirror in Embodiment 4, wherein each aspherical surface type can be defined by the formula (1) given in the above Embodiment 1.
  • Table 12 gives the total effective focal length f of the projection lens in Embodiment 4, the effective focal lengths f1 and f2 of the respective lenses, the optical total length TTL of the projection lens, the maximum half angle of view HFOV of the projection lens, and the numerical aperture of the object lens of the projection lens. NA.
  • Fig. 8 is a view showing a distortion curve of the projection lens of Embodiment 4, which shows distortion magnitude values in the case of different viewing angles. As can be seen from Fig. 8, the projection lens given in Embodiment 4 can achieve good image quality.
  • FIG. 9 is a block diagram showing the structure of a projection lens according to Embodiment 5 of the present application.
  • a projection lens sequentially includes, along the optical axis, from the image source side to the imaging side: a first lens E1, a second lens E2, and a stop STO.
  • the first lens E1 has a positive power
  • the image side surface S1 is a convex surface
  • the imaging side surface S2 is a concave surface
  • the second lens E2 has a positive power
  • the image side surface S3 is a concave surface
  • the imaging side surface S4 is a convex surface.
  • the light transmittance of the projection lens is greater than 85%.
  • Light from the image source sequentially passes through the respective surfaces S1 to S4 and is finally imaged on a projection surface (not shown) such as a projection screen.
  • Table 13 shows the surface type, radius of curvature, thickness, material, and conical coefficient of each lens of the projection lens of Example 5, in which the unit of the radius of curvature and the thickness are each mm (mm).
  • the image source side surface S1 and the image forming side surface S2 of the first lens E1 and the image source side surface S3 and the image forming side surface S4 of the second lens E2 are both aspherical.
  • Table 14 shows the high order coefficient which can be used for each aspherical mirror surface in Embodiment 5, wherein each aspherical surface type can be defined by the formula (1) given in the above Embodiment 1.
  • Table 15 gives the total effective focal length f of the projection lens in Embodiment 5, the effective focal lengths f1 and f2 of the lenses, the optical total length TTL of the projection lens, the maximum half angle of view HFOV of the projection lens, and the numerical aperture of the object lens of the projection lens. NA.
  • Fig. 10 is a view showing a distortion curve of the projection lens of Embodiment 5, which shows distortion magnitude values in the case of different viewing angles. As can be seen from Fig. 10, the projection lens given in Example 5 can achieve good image quality.
  • Embodiments 1 to 5 respectively satisfy the relationship shown in Table 16.

Landscapes

  • Physics & Mathematics (AREA)
  • General Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Lenses (AREA)

Abstract

一种投影镜头，沿光轴由像源侧至成像侧依序包括：具有正光焦度的第一透镜（E1）和具有正光焦度的第二透镜（E2）。第一透镜（E1）和第二透镜（E2）中的至少一个透镜为玻璃材质的透镜。投影镜头的总有效焦距f与第二透镜（E2）的有效焦距f2满足1＜f/f2＜1.5。

Description

投影镜头
相关申请的交叉引用
本申请要求于2017年12月19日提交于中国国家知识产权局(SIPO)的、专利申请号为201711375247.1的中国专利申请以及于2017年12月19日提交至SIPO的、专利申请号为201721780862.6的中国专利申请的优先权和权益，以上中国专利申请通过引用整体并入本文。
技术领域
本申请涉及一种投影镜头，更具体地，本申请涉及一种包括两片透镜的投影镜头。
背景技术
近年，随着科技的不断进步，三维深度应用逐步兴起，投影镜头的应用范围也越来越广。如今，芯片技术与智能算法发展迅速，利用光学投影镜头向空间物体投射图像并接收该图像信号，即可计算出具有物体位置深度信息的三维图像。具有深度信息的三维图像可进一步用于生物识别等多种深度应用开发。
用于成像的传统投影镜头，通常通过采用增加透镜数量的方式来消除各种像差并提高分辨率。但是，增加透镜数量会导致投影镜头的光学总长度增加，从而不利于实现镜头的小型化。另外，一般的大视场角投影镜头还会存在畸变量大，成像质量差等诸多问题，且无法与光学衍射元件(DOE)搭配来精确实现投影光束在目标物体上的重新分布。
发明内容
本申请提供了可适用于便携式电子产品的、可至少解决或部分解决现有技术中的上述至少一个缺点的投影镜头。
本申请的一个方面提供了这样一种投影镜头，该投影镜头沿着光 轴由像源侧至成像侧依序包括：具有正光焦度的第一透镜；以及具有正光焦度的第二透镜。其中，第一透镜和第二透镜中的至少一个透镜可为玻璃材质的透镜；以及投影镜头的总有效焦距f与第二透镜的有效焦距f2可满足1＜f/f2＜1.5。
在一个实施方式中，第一透镜的像源侧表面可为凸面，成像侧表面可为凹面；第二透镜的像源侧表面可为凹面，成像侧表面可为凸面。
在一个实施方式中，第一透镜的热膨胀系数和第二透镜的热膨胀系数中的较小的值TCE MIN可满足TCE MIN＜15×10 -6/℃。
在一个实施方式中，投影镜头的最大半视场角HFOV可满足0＜TAN(HFOV)＜0.35。
在一个实施方式中，在800nm至1000nm的光波波段中，投影镜头的光线透过率可大于85％。
在一个实施方式中，第一透镜于光轴上的中心厚度CT1与第二透镜于光轴上的中心厚度CT2可满足0.6＜CT1/CT2＜1.2。
在一个实施方式中，第一透镜于光轴上的中心厚度CT1、第二透镜于光轴上的中心厚度CT2与投影镜头的光学总长度TTL可满足0.4＜(CT1+CT2)/TTL＜0.8。
在一个实施方式中，第一透镜的像源侧表面的曲率半径R1与第二透镜的成像侧表面的曲率半径R4可满足-1.2＜R1/R4＜-0.8。
在一个实施方式中，第一透镜的像源侧表面的有效半口径DT11与第二透镜的成像侧表面的有效半口径DT22可满足0.7＜DT11/DT22＜1。
在一个实施方式中，投影镜头的总有效焦距f、第一透镜的有效焦距f1与第二透镜的有效焦距f2可满足0.5＜f/(f1+f2)＜0.8。
本申请的一个方面提供了这样一种投影镜头，该投影镜头沿着光轴由像源侧至成像侧依序包括：具有正光焦度的第一透镜；以及具有正光焦度的第二透镜。其中，第一透镜和第二透镜中的至少一个透镜可为玻璃材质的透镜；以及投影镜头的总有效焦距f、第一透镜的有效焦距f1与第二透镜的有效焦距f2可满足0.5＜f/(f1+f2)＜0.8。
本申请的一个方面提供了这样一种投影镜头，该投影镜头沿着光轴由像源侧至成像侧依序包括：具有正光焦度的第一透镜；以及具有正光焦度的第二透镜。其中，第一透镜和第二透镜中的至少一个透镜可为玻璃材质的透镜；以及第一透镜的像源侧表面的有效半口径DT11与第二透镜的成像侧表面的有效半口径DT22可满足0.7＜DT11/DT22＜1。
本申请采用了多片(例如，两片)透镜，通过合理选用透镜材质以及合理分配各透镜的光焦度、面型、各透镜的中心厚度以及各透镜之间的轴上间距等，使得上述投影镜头具有高性能、小型化、低温漂、高成像品质等至少一个有益效果，且上述投影镜头能够与光学衍射元件(DOE)配合使用。
附图说明
结合附图，通过以下非限制性实施方式的详细描述，本申请的其他特征、目的和优点将变得更加明显。在附图中：
图1示出了根据本申请实施例1的投影镜头的结构示意图；
图2示出了实施例1的投影镜头的畸变曲线；
图3示出了根据本申请实施例2的投影镜头的结构示意图；
图4示出了实施例2的投影镜头的畸变曲线；
图5示出了根据本申请实施例3的投影镜头的结构示意图；
图6示出了实施例3的投影镜头的畸变曲线；
图7示出了根据本申请实施例4的投影镜头的结构示意图；
图8示出了实施例4的投影镜头的畸变曲线；
图9示出了根据本申请实施例5的投影镜头的结构示意图；
图10示出了实施例5的投影镜头的畸变曲线；
图11示出了根据本申请的投影镜头与衍射元件配合使用的示意图。
具体实施方式
为了更好地理解本申请，将参考附图对本申请的各个方面做出更详细的说明。应理解，这些详细说明只是对本申请的示例性实施方式的描述，而非以任何方式限制本申请的范围。在说明书全文中，相同的附图标号指代相同的元件。表述“和/或”包括相关联的所列项目中的一个或多个的任何和全部组合。
应注意，在本说明书中，第一、第二等的表述仅用于将一个特征与另一个特征区分开来，而不表示对特征的任何限制。因此，在不背离本申请的教导的情况下，下文中讨论的第一透镜也可被称作第二透镜，第二透镜也可被称作第一透镜。
在附图中，为了便于说明，已稍微夸大了透镜的厚度、尺寸和形状。具体来讲，附图中所示的球面或非球面的形状通过示例的方式示出。即，球面或非球面的形状不限于附图中示出的球面或非球面的形状。附图仅为示例而并非严格按比例绘制。
在本文中，近轴区域是指光轴附近的区域。若透镜表面为凸面且未界定该凸面位置时，则表示该透镜表面至少于近轴区域为凸面；若透镜表面为凹面且未界定该凹面位置时，则表示该透镜表面至少于近轴区域为凹面。每个透镜中最靠近像源侧的表面称为像源侧表面，每个透镜中最靠近成像侧的表面称为成像侧表面。
还应理解的是，用语“包括”、“包括有”、“具有”、“包含”和/或“包含有”，当在本说明书中使用时表示存在所陈述的特征、元件和/或部件，但不排除存在或附加有一个或多个其它特征、元件、部件和/或它们的组合。此外，当诸如“...中的至少一个”的表述出现在所列特征的列表之后时，修饰整个所列特征，而不是修饰列表中的单独元件。此外，当描述本申请的实施方式时，使用“可”表示“本申请的一个或多个实施方式”。并且，用语“示例性的”旨在指代示例或举例说明。
除非另外限定，否则本文中使用的所有用语(包括技术用语和科学用语)均具有与本申请所属领域普通技术人员的通常理解相同的含义。还应理解的是，用语(例如在常用词典中定义的用语)应被解释为具有与它们在相关技术的上下文中的含义一致的含义，并且将不被以理想化或过度正式意义解释，除非本文中明确如此限定。
需要说明的是，在不冲突的情况下，本申请中的实施例及实施例中的特征可以相互组合。下面将参考附图并结合实施例来详细说明本申请。
以下对本申请的特征、原理和其他方面进行详细描述。
根据本申请示例性实施方式的投影镜头可包括例如两片具有光焦度的透镜，即，第一透镜和第二透镜。这两片透镜沿着光轴由像源侧至成像侧依序排列。
在示例性实施方式中，第一透镜可具有正光焦度，第二透镜可具有正光焦度。合理分配各透镜的光焦度与面型，有利于提高投影镜头的性能；同时，有利于减小镜头总长，保证镜头的小型化。
在示例性实施方式中，第一透镜的像源侧表面可为凸面，成像侧表面可为凹面；第二透镜的像源侧表面可为凹面，成像侧表面可为凸面。合理分配和透镜的面型，有利于实现镜头高性能、低敏感性的功效。
在示例性实施方式中，本申请的投影镜头可满足条件式TCE MIN＜15×10 -6/℃，其中，TCE MIN为第一透镜的热膨胀系数和第二透镜的热膨胀系数中较小的值。更具体地，TCE MIN进一步可满足0.00×10 -6/℃≤TCE MIN≤9.50×10 -6/℃。第一透镜和第二透镜中的至少一个透镜为玻璃材质的透镜。合理采用玻璃材质的透镜，有利于降低温漂。
在示例性实施方式中，本申请的投影镜头可满足条件式0＜TAN(HFOV)＜0.35，其中，HFOV为投影镜头的最大半视场角。更具体地，HFOV进一步可满足0.1＜TAN(HFOV)＜0.2，例如，0.15≤TAN(HFOV)≤0.16。有利于降低像源在像侧的尺寸影响，提升投影镜头的光学性能。
在示例性实施方式中，本申请的投影镜头可满足条件式0.6＜CT1/CT2＜1.2，其中，CT1为第一透镜于光轴上的中心厚度，CT2为第二透镜于光轴上的中心厚度。更具体地，CT1和CT2进一步可满足0.61≤CT1/CT2≤1.06。合理分配第一透镜和第二透镜的中心厚度，有利于保证镜头具有较短总长，实现小型化特性。
在示例性实施方式中，本申请的投影镜头可满足条件式0.4＜(CT1+CT2)/TTL＜0.8，其中，CT1为第一透镜于光轴上的中心厚度，CT2为第二透镜于光轴上的中心厚度，TTL为投影镜头的光学总长度(即，从像源至第二透镜的成像侧表面的中心在光轴上的距离)。更具体地，CT1、CT2和TTL进一步可满足0.50≤(CT1+CT2)/TTL≤0.76。满足条件式0.4＜(CT1+CT2)/TTL＜0.8，有利于实现镜头的小型化功效。
在示例性实施方式中，本申请的投影镜头可满足条件式-1.2＜R1/R4＜-0.8，其中，R1为第一透镜的像源侧表面的曲率半径，R4为第二透镜的成像侧表面的曲率半径。更具体地，R1和R4进一步可满足-1.15≤R1/R4≤-0.82。合理分配第一透镜和第二透镜的曲率半径，有利于降低镜头的敏感性。
在示例性实施方式中，本申请的投影镜头可满足条件式0.7＜DT11/DT22＜1，其中，DT11为第一透镜的像源侧表面的有效半口径，DT22为第二透镜的成像侧表面的有效半口径。更具体地，DT11和DT22进一步可满足0.7＜DT11/DT22＜0.9，例如，0.78≤DT11/DT22≤0.83。满足条件式0.7＜DT11/DT22＜1，有利于降低像源在像侧的尺寸影响，提升投影镜头的光学性能。合理分配DT11和DT22还有利于避免由于光线过度弯折而造成的成像质量的下降。
在示例性实施方式中，本申请的投影镜头在约800nm至约1000nm的光波波段中，光线透过率大于85％。这样的设置有利于提高近红外光线透过投影镜头的透过率，从而获得更高亮度的近红外投影图像。
在示例性实施方式中，本申请的投影镜头可满足条件式1＜f/f2＜1.5，其中，f为投影镜头的总有效焦距，f2为第二透镜的有效焦距。更具体地，f和f2进一步可满足1.11≤f/f2≤1.48。合理分配第二透镜的光焦度，有利于降低温漂，提升镜头的光学性能。
在示例性实施方式中，本申请的投影镜头可满足条件式0.5＜f/(f1+f2)＜0.8，其中，f为投影镜头的总有效焦距，f1为第一透镜的有效焦距，f2为第二透镜的有效焦距。更具体地，f、f1和f2进一步可满足0.55≤f/(f1+f2)≤0.66。合理分配第一透镜和第二透镜的光焦度， 有利于实现镜头的高性能。
在示例性实施方式中，上述投影镜头还可包括至少一个光阑，以提升镜头的成像质量。光阑可根据需要设置在任意位置处，例如，光阑可设置在第二透镜与成像侧之间。
可选地，上述投影镜头还可包括其他公知的光学投影元件，例如，棱镜、场镜等。相比于普通镜头，投影镜头主要区别在于，一般摄像镜头的光线从物侧至成像侧形成一个像面；而一般投影镜头的光线从像源侧至成像侧，将像面放大投射直至投影面。一般投影镜头的进光量由物方数值孔径与镜头光阑控制。根据本申请的上述实施方式的投影镜头可采用例如两片透镜，通过合理选取透镜的材质并合理分配各透镜的光焦度、面型、各透镜的中心厚度以及各透镜之间的轴上间距等，使得投影镜头具有高性能、小型化、低温漂、高成像品质等有益效果。
根据本申请的投影镜头可作为散斑投影镜头应用于深度探测领域。如图11所示，当使用本申请的投影镜头对空间中的目标物体进行深度探测时，由红外激光二极管(LD)或垂直腔面发射激光器(VCSEL)发出的光线会先经过投影镜头斑点放大，再经过光学衍射元件(DOE)，而后向目标物体方向投射出去。投影光束在经过光学衍射元件(DOE)后，可以实现投影图像在目标物体上的重新分布。其后，通过任意公知的摄像镜头(未示出)捕捉投射到目标物体上的图像信息，即可计算出具有目标物体位置深度信息的三维图像。根据本申请的投影镜头能够与光学衍射元件(DOE)相互配合使用，从而精确实现投影光束在目标物体上的重新分布。
在本申请的实施方式中，各透镜的镜面中的至少一个为非球面镜面。非球面透镜的特点是：从透镜中心到透镜周边，曲率是连续变化的。与从透镜中心到透镜周边具有恒定曲率的球面透镜不同，非球面透镜具有更佳的曲率半径特性，具有改善歪曲像差及改善像散像差的优点。采用非球面透镜后，能够尽可能地消除在成像的时候出现的像差，从而改善成像质量。
然而，本领域的技术人员应当理解，在未背离本申请要求保护的 技术方案的情况下，可改变构成投影镜头的透镜数量，来获得本说明书中描述的各个结果和优点。例如，虽然在实施方式中以两片透镜为例进行了描述，但是该投影镜头不限于包括两片透镜。如果需要，该投影镜头还可包括其它数量的透镜。
下面参照附图进一步描述可适用于上述实施方式的投影镜头的具体实施例。
                      实施例1
以下参照图1至图2描述根据本申请实施例1的投影镜头。图1示出了根据本申请实施例1的投影镜头的结构示意图。
如图1所示，根据本申请示例性实施方式的投影镜头沿光轴由像源侧至成像侧依序包括：第一透镜E1、第二透镜E2和光阑STO。
第一透镜E1具有正光焦度，其像源侧表面S1为凸面，成像侧表面S2为凹面。第二透镜E2具有正光焦度，其像源侧表面S3为凹面，成像侧表面S4为凸面。在约800nm至约1000nm光波波段中，该投影镜头的光线透过率大于85％。来自像源的光依序穿过各表面S1至S4并最终成像在例如投影屏幕的投影面上(未示出)。
表1示出了实施例1的投影镜头的各透镜的表面类型、曲率半径、厚度、材料及圆锥系数，其中，曲率半径和厚度的单位均为毫米(mm)。
Figure PCTCN2018088685-appb-000001
表1
由表1可知，第一透镜E1的像源侧表面S1和成像侧表面S2以及第二透镜E2的像源侧表面S3和成像侧表面S4均为非球面。在本实施例中，各非球面透镜的面型x可利用但不限于以下非球面公式进 行限定：
Figure PCTCN2018088685-appb-000002
其中，x为非球面沿光轴方向在高度为h的位置时，距非球面顶点的距离矢高；c为非球面的近轴曲率，c＝1/R(即，近轴曲率c为上表1中曲率半径R的倒数)；k为圆锥系数(在表1中已给出)；Ai是非球面第i-th阶的修正系数。下表2给出了可用于实施例1中各非球面镜面S1-S4的高次项系数A 4、A 6、A 8、A 10、A 12、A 14和A 16。
面号 A4 A6 A8 A10 A12 A14 A16
S1 6.6779E-02 -2.1533E-01 6.7938E-01 -3.4057E+00 6.8954E+00 -3.9692E+00 -4.5296E+00
S2 6.7146E-01 -6.3408E-01 2.5150E+01 -1.3173E+02 6.3999E+01 2.8529E+03 -8.0409E+03
S3 -6.6496E-02 -1.0255E-01 1.5182E+00 -1.6356E+01 8.5757E+01 -2.2034E+02 2.3336E+02
S4 2.1740E-02 2.1568E-02 8.1556E-04 7.4412E-04 1.1502E-01 -1.5533E-01 1.1233E-01
表2
表3给出实施例1中投影镜头的总有效焦距f、各透镜的有效焦距f1和f2、投影镜头的光学总长度TTL(即，从像源OBJ至第二透镜E2的成像侧表面S4的中心在光轴上的距离)、投影镜头的最大半视场角HFOV以及投影镜头的物方数值孔径NA。
参数 f(mm) f1(mm) f2(mm) TTL(mm) HFOV(°) NA
数值 3.39 3.37 2.77 3.45 8.4 0.20
表3
实施例1中的投影镜头满足：
TAN(HFOV)＝0.15，其中，HFOV为投影镜头的最大半视场角；
CT1/CT2＝0.61，其中，CT1为第一透镜E1于光轴上的中心厚度，CT2为第二透镜E2于光轴上的中心厚度；
(CT1+CT2)/TTL＝0.50，其中，CT1为第一透镜E1于光轴上的中心厚度，CT2为第二透镜E2于光轴上的中心厚度，TTL为投影镜头的光学总长度；
R1/R4＝-0.83，其中，R1为第一透镜E1的像源侧表面S1的曲率半径，R4为第二透镜E2的成像侧表面S4的曲率半径；
DT11/DT22＝0.80，其中，DT11为第一透镜E1的像源侧表面S1的有效半口径，DT22为第二透镜E2的成像侧表面S4的有效半口径；
f/f2＝1.22，其中，f为投影镜头的总有效焦距，f2为第二透镜E2的有效焦距；
f/(f1+f2)＝0.55，其中，f为投影镜头的总有效焦距，f1为第一透镜E1的有效焦距，f2为第二透镜E2的有效焦距；
TCE MIN＝0.00×10 -6/℃，其中，TCE MIN为第一透镜E1的热膨胀系数和第二透镜E2的热膨胀系数中较小的值。
图2示出了实施例1的投影镜头的畸变曲线，其表示不同视角情况下的畸变大小值。根据图2可知，实施例1所给出的投影镜头能够实现良好的成像品质。
                       实施例2
以下参照图3至图4描述根据本申请实施例2的投影镜头。在本实施例及以下实施例中，为简洁起见，将省略部分与实施例1相似的描述。图3示出了根据本申请实施例2的投影镜头的结构示意图。
如图3所示，根据本申请示例性实施方式的投影镜头沿光轴由像源侧至成像侧依序包括：第一透镜E1、第二透镜E2和光阑STO。
第一透镜E1具有正光焦度，其像源侧表面S1为凸面，成像侧表面S2为凹面。第二透镜E2具有正光焦度，其像源侧表面S3为凹面，成像侧表面S4为凸面。在约800nm至约1000nm光波波段中，该投影镜头的光线透过率大于85％。来自像源的光依序穿过各表面S1至S4并最终成像在例如投影屏幕的投影面上(未示出)。
表4示出了实施例2的投影镜头的各透镜的表面类型、曲率半径、厚度、材料及圆锥系数，其中，曲率半径和厚度的单位均为毫米(mm)。
Figure PCTCN2018088685-appb-000003
Figure PCTCN2018088685-appb-000004
表4
由表4可知，在实施例2中，第一透镜E1的像源侧表面S1和成像侧表面S2以及第二透镜E2的像源侧表面S3和成像侧表面S4均为非球面。表5示出了可用于实施例2中各非球面镜面的高次项系数，其中，各非球面面型可由上述实施例1中给出的公式(1)限定。
面号 A4 A6 A8 A10 A12 A14 A16
S1 -6.6061E-02 1.0707E-01 -5.2668E+00 3.3949E+01 -1.2315E+02 2.2354E+02 -1.6954E+02
S2 6.4678E-01 -3.7800E+00 1.1027E+02 -1.6006E+03 1.2745E+04 -5.2495E+04 8.7013E+04
S3 -4.7767E-02 -2.3954E-01 3.9808E-01 -1.7446E+01 1.4517E+02 -7.7484E+02 6.7842E+01
S4 -2.8044E-03 1.5669E-03 -3.8248E-02 1.3579E-01 -2.9681E-01 3.1658E-01 -1.3674E-01
表5
表6给出实施例2中投影镜头的总有效焦距f、各透镜的有效焦距f1和f2、投影镜头的光学总长度TTL、投影镜头的最大半视场角HFOV以及投影镜头的物方数值孔径NA。
参数 f(mm) f1(mm) f2(mm) TTL(mm) HFOV(°) NA
数值 3.13 2.41 2.81 3.45 9.1 0.20
表6
图4示出了实施例2的投影镜头的畸变曲线，其表示不同视角情况下的畸变大小值。根据图4可知，实施例2所给出的投影镜头能够实现良好的成像品质。
                          实施例3
以下参照图5至图6描述了根据本申请实施例3的投影镜头。图5示出了根据本申请实施例3的投影镜头的结构示意图。
如图5所示，根据本申请示例性实施方式的投影镜头沿光轴由像源侧至成像侧依序包括：第一透镜E1、第二透镜E2和光阑STO。
第一透镜E1具有正光焦度，其像源侧表面S1为凸面，成像侧表面S2为凹面。第二透镜E2具有正光焦度，其像源侧表面S3为凹面，成像侧表面S4为凸面。在约800nm至约1000nm光波波段中，该投影镜头的光线透过率大于85％。来自像源的光依序穿过各表面S1至S4并最终成像在例如投影屏幕的投影面上(未示出)。
表7示出了实施例3的投影镜头的各透镜的表面类型、曲率半径、厚度、材料及圆锥系数，其中，曲率半径和厚度的单位均为毫米(mm)。
Figure PCTCN2018088685-appb-000005
表7
由表7可知，在实施例3中，第一透镜E1的像源侧表面S1和成像侧表面S2以及第二透镜E2的像源侧表面S3和成像侧表面S4均为非球面。表8示出了可用于实施例3中各非球面镜面的高次项系数，其中，各非球面面型可由上述实施例1中给出的公式(1)限定。
面号 A4 A6 A8 A10 A12 A14 A16
S1 -5.4910E-02 7.1496E-03 -4.8775E-01 4.6674E-01 2.2280E+00 -7.8840E+00 6.5804E+00
S2 5.7693E-01 7.5933E-01 1.7444E+01 -1.9770E+02 1.6471E+03 -4.8654E+03 2.1756E+03
S3 1.7187E-03 1.8159E-01 5.0055E-01 -1.0146E+00 2.9928E+01 -9.7953E+01 3.1718E+02
S4 2.3711E-02 1.8801E-02 6.6387E-02 -1.7402E-01 4.7586E-01 -4.8873E-01 2.6749E-01
表8
表9给出实施例3中投影镜头的总有效焦距f、各透镜的有效焦距f1和f2、投影镜头的光学总长度TTL、投影镜头的最大半视场角HFOV以及投影镜头的物方数值孔径NA。
参数 f(mm) f1(mm) f2(mm) TTL(mm) HFOV(°) NA
数值 3.20 2.87 2.17 3.45 8.9 0.20
表9
图6示出了实施例3的投影镜头的畸变曲线，其表示不同视角情况下的畸变大小值。根据图6可知，实施例3所给出的投影镜头能够实现良好的成像品质。
                       实施例4
以下参照图7至图8描述了根据本申请实施例4的投影镜头。图7示出了根据本申请实施例4的投影镜头的结构示意图。
如图7所示，根据本申请示例性实施方式的投影镜头沿光轴由像源侧至成像侧依序包括：第一透镜E1、第二透镜E2和光阑STO。
第一透镜E1具有正光焦度，其像源侧表面S1为凸面，成像侧表面S2为凹面。第二透镜E2具有正光焦度，其像源侧表面S3为凹面，成像侧表面S4为凸面。在约800nm至约1000nm光波波段中，该投影镜头的光线透过率大于85％。来自像源的光依序穿过各表面S1至S4并最终成像在例如投影屏幕的投影面上(未示出)。
表10示出了实施例4的投影镜头的各透镜的表面类型、曲率半径、厚度、材料及圆锥系数，其中，曲率半径和厚度的单位均为毫米(mm)。
Figure PCTCN2018088685-appb-000006
表10
由表10可知，在实施例4中，第一透镜E1的像源侧表面S1和成像侧表面S2以及第二透镜E2的像源侧表面S3和成像侧表面S4均为非球面。表11示出了可用于实施例4中各非球面镜面的高次项系数，其中，各非球面面型可由上述实施例1中给出的公式(1)限定。
Figure PCTCN2018088685-appb-000007
Figure PCTCN2018088685-appb-000008
表11
表12给出实施例4中投影镜头的总有效焦距f、各透镜的有效焦距f1和f2、投影镜头的光学总长度TTL、投影镜头的最大半视场角HFOV以及投影镜头的物方数值孔径NA。
参数 f(mm) f1(mm) f2(mm) TTL(mm) HFOV(°) NA
数值 3.25 2.88 2.89 3.45 9.0 0.20
表12
图8示出了实施例4的投影镜头的畸变曲线，其表示不同视角情况下的畸变大小值。根据图8可知，实施例4所给出的投影镜头能够实现良好的成像品质。
                      实施例5
以下参照图9至图10描述了根据本申请实施例5的投影镜头。图9示出了根据本申请实施例5的投影镜头的结构示意图。
如图9所示，根据本申请示例性实施方式的投影镜头沿光轴由像源侧至成像侧依序包括：第一透镜E1、第二透镜E2和光阑STO。
第一透镜E1具有正光焦度，其像源侧表面S1为凸面，成像侧表面S2为凹面。第二透镜E2具有正光焦度，其像源侧表面S3为凹面，成像侧表面S4为凸面。在约800nm至约1000nm光波波段中，该投影镜头的光线透过率大于85％。来自像源的光依序穿过各表面S1至S4并最终成像在例如投影屏幕的投影面上(未示出)。
表13示出了实施例5的投影镜头的各透镜的表面类型、曲率半径、厚度、材料及圆锥系数，其中，曲率半径和厚度的单位均为毫米(mm)。
Figure PCTCN2018088685-appb-000009
Figure PCTCN2018088685-appb-000010
表13
由表13可知，在实施例5中，第一透镜E1的像源侧表面S1和成像侧表面S2以及第二透镜E2的像源侧表面S3和成像侧表面S4均为非球面。表14示出了可用于实施例5中各非球面镜面的高次项系数，其中，各非球面面型可由上述实施例1中给出的公式(1)限定。
面号 A4 A6 A8 A10 A12 A14 A16
S1 -1.6234E-01 8.7888E-01 -8.6559E+00 3.9419E+01 -1.0705E+02 1.5614E+02 -9.8248E+01
S2 9.4369E-01 4.5172E+00 -2.5322E+01 2.4299E+02 -1.7173E+02 0.0000E+00 0.0000E+00
S3 -2.8546E+00 2.6308E+01 -2.6771E+02 1.6990E+03 -5.8668E+03 7.7236E+03 0.0000E+00
S4 -5.8240E-03 -9.0683E-02 6.7866E-01 -3.0133E+00 7.0028E+00 -8.3009E+00 3.8635E+00
表14
表15给出实施例5中投影镜头的总有效焦距f、各透镜的有效焦距f1和f2、投影镜头的光学总长度TTL、投影镜头的最大半视场角HFOV以及投影镜头的物方数值孔径NA。
参数 f(mm) f1(mm) f2(mm) TTL(mm) HFOV(°) NA
数值 3.33 2.48 2.54 3.50 9.0 0.20
表15
图10示出了实施例5的投影镜头的畸变曲线，其表示不同视角情况下的畸变大小值。根据图10可知，实施例5所给出的投影镜头能够实现良好的成像品质。
综上，实施例1至实施例5分别满足表16中所示的关系。
条件式\实施例 1 2 3 4 5
TAN(HFOV) 0.15 0.16 0.16 0.16 0.16
CT1/CT2 0.61 1.00 0.93 1.06 0.82
(CT1+CT2)/TTL 0.50 0.69 0.69 0.76 0.71
R1/R4 -0.83 -1.15 -1.06 -1.01 -0.82
DT11/DT22 0.80 0.83 0.83 0.78 0.81
f/f2 1.22 1.11 1.48 1.12 1.31
f/(f1+f2) 0.55 0.60 0.64 0.56 0.66
TCE MIN(×10 -6/℃) 0.00 9.50 7.60 9.50 6.10
表16
以上描述仅为本申请的较佳实施例以及对所运用技术原理的说明。本领域技术人员应当理解，本申请中所涉及的发明范围，并不限于上述技术特征的特定组合而成的技术方案，同时也应涵盖在不脱离所述发明构思的情况下，由上述技术特征或其等同特征进行任意组合而形成的其它技术方案。例如上述特征与本申请中公开的(但不限于)具有类似功能的技术特征进行互相替换而形成的技术方案。

Claims (22)

  1. 投影镜头，其特征在于，沿着光轴由像源侧至成像侧依序包括：
    具有正光焦度的第一透镜；
    具有正光焦度的第二透镜；
    所述第一透镜和所述第二透镜中的至少一个透镜为玻璃材质的透镜；以及
    所述投影镜头的总有效焦距f与所述第二透镜的有效焦距f2满足1＜f/f2＜1.5。
  2. 根据权利要求1所述的投影镜头，其特征在于，所述第一透镜的像源侧表面为凸面，成像侧表面为凹面。
  3. 根据权利要求1所述的投影镜头，其特征在于，所述第二透镜的像源侧表面为凹面，成像侧表面为凸面。
  4. 根据权利要求1所述的投影镜头，其特征在于，所述第一透镜的热膨胀系数和所述第二透镜的热膨胀系数中的较小的值TCE MIN满足TCE MIN＜15×10 -6/℃。
  5. 根据权利要求1所述的投影镜头，其特征在于，所述投影镜头的最大半视场角HFOV满足0＜TAN(HFOV)＜0.35。
  6. 根据权利要求1所述的投影镜头，其特征在于，在800nm至1000nm的光波波段中，所述投影镜头的光线透过率大于85％。
  7. 根据权利要求1至6中任一项所述的投影镜头，其特征在于，所述第一透镜于所述光轴上的中心厚度CT1与所述第二透镜于所述光轴上的中心厚度CT2满足0.6＜CT1/CT2＜1.2。
  8. 根据权利要求1至6中任一项所述的投影镜头，其特征在于， 所述第一透镜于所述光轴上的中心厚度CT1、所述第二透镜于所述光轴上的中心厚度CT2与所述投影镜头的光学总长度TTL满足0.4＜(CT1+CT2)/TTL＜0.8。
  9. 根据权利要求1至6中任一项所述的投影镜头，其特征在于，所述第一透镜的像源侧表面的曲率半径R1与所述第二透镜的成像侧表面的曲率半径R4满足-1.2＜R1/R4＜-0.8。
  10. 根据权利要求1至6中任一项所述的投影镜头，其特征在于，所述第一透镜的像源侧表面的有效半口径DT11与所述第二透镜的成像侧表面的有效半口径DT22满足0.7＜DT11/DT22＜1。
  11. 根据权利要求1至6中任一项所述的投影镜头，其特征在于，所述投影镜头的总有效焦距f、所述第一透镜的有效焦距f1与所述第二透镜的有效焦距f2满足0.5＜f/(f1+f2)＜0.8。
  12. 投影镜头，其特征在于，沿光轴由像源侧至成像侧依序包括：
    具有正光焦度的第一透镜；
    具有正光焦度的第二透镜；
    所述第一透镜和所述第二透镜中的至少一个透镜为玻璃材质的透镜；以及
    所述投影镜头的总有效焦距f、所述第一透镜的有效焦距f1与所述第二透镜的有效焦距f2满足0.5＜f/(f1+f2)＜0.8。
  13. 根据权利要求12所述的投影镜头，其特征在于，所述第一透镜的像源侧表面为凸面，成像侧表面为凹面。
  14. 根据权利要求13所述的投影镜头，其特征在于，所述第二透镜的像源侧表面为凹面，成像侧表面为凸面。
  15. 根据权利要求14所述的投影镜头，其特征在于，所述第一透镜于所述光轴上的中心厚度CT1与所述第二透镜于所述光轴上的中心厚度CT2满足0.6＜CT1/CT2＜1.2。
  16. 根据权利要求14所述的投影镜头，其特征在于，所述第一透镜于所述光轴上的中心厚度CT1、所述第二透镜于所述光轴上的中心厚度CT2与所述投影镜头的光学总长度TTL满足0.4＜(CT1+CT2)/TTL＜0.8。
  17. 根据权利要求14所述的投影镜头，其特征在于，所述第一透镜的像源侧表面的曲率半径R1与所述第二透镜的成像侧表面的曲率半径R4满足-1.2＜R1/R4＜-0.8。
  18. 根据权利要求14所述的投影镜头，其特征在于，所述投影镜头的总有效焦距f与所述第二透镜的有效焦距f2满足1＜f/f2＜1.5。
  19. 根据权利要求14所述的投影镜头，其特征在于，所述第一透镜的像源侧表面的有效半口径DT11与所述第二透镜的成像侧表面的有效半口径DT22满足0.7＜DT11/DT22＜1。
  20. 根据权利要求12至19中任一项所述的投影镜头，其特征在于，所述第一透镜的热膨胀系数和所述第二透镜的热膨胀系数中的较小的值TCE MIN满足TCE MIN＜15×10 -6/℃。
  21. 根据权利要求12至19中任一项所述的投影镜头，其特征在于，所述投影镜头的最大半视场角HFOV满足0＜TAN(HFOV)＜0.35。
  22. 根据权利要求12至19中任一项所述的投影镜头，其特征在于，在800nm至1000nm的光波波段中，所述投影镜头的光线透过率大于85％。
PCT/CN2018/088685 2017-12-19 2018-05-28 投影镜头 WO2019119728A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US16/293,103 US11143843B2 (en) 2017-12-19 2019-03-05 Projection lens assembly

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
CN201711375247.1 2017-12-19
CN201721780862.6U CN207516712U (zh) 2017-12-19 2017-12-19 投影镜头
CN201711375247.1A CN107861317B (zh) 2017-12-19 2017-12-19 投影镜头
CN201721780862.6 2017-12-19

Related Child Applications (1)

Application Number Title Priority Date Filing Date
US16/293,103 Continuation US11143843B2 (en) 2017-12-19 2019-03-05 Projection lens assembly

Publications (1)

Publication Number Publication Date
WO2019119728A1 true WO2019119728A1 (zh) 2019-06-27

Family

ID=66994365

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2018/088685 WO2019119728A1 (zh) 2017-12-19 2018-05-28 投影镜头

Country Status (1)

Country Link
WO (1) WO2019119728A1 (zh)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20210072506A1 (en) * 2019-09-06 2021-03-11 Zhejiang Sunny Optical Co., Ltd Optical imaging lens assembly

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09203858A (ja) * 1996-01-25 1997-08-05 Olympus Optical Co Ltd 読み取り用レンズ
US6295168B1 (en) * 1999-12-15 2001-09-25 International Business Machines Corporation Refractive optical system that converts a laser beam to a collimated flat-top beam
TW200916873A (en) * 2007-10-09 2009-04-16 Largan Precision Co Ltd Two-lens type lens system for taking image
CN101490595A (zh) * 2006-07-20 2009-07-22 株式会社尼康 光学系统及目镜
CN107436484A (zh) * 2017-09-15 2017-12-05 江西联创电子有限公司 投影镜头
CN107861317A (zh) * 2017-12-19 2018-03-30 浙江舜宇光学有限公司 投影镜头

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09203858A (ja) * 1996-01-25 1997-08-05 Olympus Optical Co Ltd 読み取り用レンズ
US6295168B1 (en) * 1999-12-15 2001-09-25 International Business Machines Corporation Refractive optical system that converts a laser beam to a collimated flat-top beam
CN101490595A (zh) * 2006-07-20 2009-07-22 株式会社尼康 光学系统及目镜
TW200916873A (en) * 2007-10-09 2009-04-16 Largan Precision Co Ltd Two-lens type lens system for taking image
CN107436484A (zh) * 2017-09-15 2017-12-05 江西联创电子有限公司 投影镜头
CN107861317A (zh) * 2017-12-19 2018-03-30 浙江舜宇光学有限公司 投影镜头

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20210072506A1 (en) * 2019-09-06 2021-03-11 Zhejiang Sunny Optical Co., Ltd Optical imaging lens assembly
US11733485B2 (en) * 2019-09-06 2023-08-22 Zhejiang Sunny Optical Co., Ltd Optical imaging lens assembly

Similar Documents

Publication Publication Date Title
WO2019169889A1 (zh) 投影镜头
WO2018145367A1 (zh) 目镜以及包括该目镜的显示装置
US11137573B2 (en) Projection lens assembly
WO2020073703A1 (zh) 光学透镜组
CN107783258B (zh) 投影镜头
WO2019056817A1 (zh) 光学成像系统
WO2019233040A1 (zh) 摄像透镜组
CN107861317B (zh) 投影镜头
WO2019184367A1 (zh) 光学系统
WO2019137055A1 (zh) 摄像透镜系统
WO2019052220A1 (zh) 光学成像镜头
WO2019218628A1 (zh) 光学成像镜头
CN107831630B (zh) 投影镜头
CN207516711U (zh) 投影镜头
WO2018209890A1 (zh) 成像镜头
WO2019210676A1 (zh) 摄像镜头
US11143843B2 (en) Projection lens assembly
WO2019192160A1 (zh) 光学成像镜头
WO2018223651A1 (zh) 摄像镜头
WO2019000986A1 (zh) 光学成像系统
WO2019024490A1 (zh) 光学成像镜头
TWI457632B (zh) 成像系統鏡組
WO2019019530A1 (zh) 光学成像镜头
CN107728295B (zh) 投影镜头
WO2019114189A1 (zh) 光学成像系统

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 18892548

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 18892548

Country of ref document: EP

Kind code of ref document: A1

122 Ep: pct application non-entry in european phase

Ref document number: 18892548

Country of ref document: EP

Kind code of ref document: A1