Combined lens, optical system and optical lens

Abstract

The utility model discloses a combined lens, an optical system and an optical lens, the combined lens comprises a lens main body and a diffractive optical element, and the lens main body allows light of a target wave band to pass through; the lens main body comprises a refracting surface and a structural surface, the refracting surface is configured to modulate incident light through refraction, and the structural surface is located on any side of the lens main body in the thickness direction; the diffractive optical element is arranged on the structural surface, and the diffractive optical element is configured to modulate incident light through diffraction. The combined lens provided by the utility model comprises the lens main body and the diffractive optical element, the diffractive optical element is configured to modulate the incident light through diffraction, the diffractive optical element has high design freedom and good machinability, and the diffractive optical element is matched with the refraction surface of the lens main body to modulate the light. Therefore, the combined lens has excellent optical performance and can be widely applied to various optical systems.

Description

Technical Field

[0001] This application relates to the field of lenses, and more particularly to a combination lens, optical system, and optical lens. Background Technology

[0002] Traditional refractive lenses modulate light based on the principle of refraction. However, traditional lenses are limited by the Abbe number, refractive index, and manufacturability, which greatly restricts their degree of freedom and makes it impossible to achieve high degree of freedom in phase modulation. This makes it difficult to further improve the optical performance of optical systems designed based on traditional refractive lenses. Utility Model Content

[0003] To address the aforementioned technical problems, embodiments of this application provide a combined lens, an optical system, and an optical lens, aiming to provide a combined lens with high design freedom and excellent optical performance.

[0004] According to one aspect of the embodiments of this application, a combination lens is disclosed, the combination lens comprising:

[0005] The lens body allows light of the target wavelength to pass through; the lens body includes a refractive surface and a structural surface, the refractive surface being configured to modulate incident light through refraction, and the structural surface being located on any side of the thickness direction of the lens body;

[0006] A diffractive optical element is disposed on the structural surface, and the diffractive optical element is configured to modulate the incident light through diffraction.

[0007] In some embodiments, the combined lens satisfies: 0 < n × |C d |<0.5, where n is the refractive index of the lens body, C d Let be the curvature of the refracting surface.

[0008] In some embodiments, the combined lens satisfies: 0mm < |f z |<30000mm, where, f z is the focal length of the combined lens.

[0009] In some embodiments, the combined lens satisfies: Among them, f m f is the focal length of the diffractive optical element. z is the focal length of the combined lens.

[0010] In some embodiments, the diffractive optical element is any one of a metasurface, a Fresnel surface, and a grating surface.

[0011] In some embodiments, the target band includes at least one of the visible light band, the near-infrared band, and the far-infrared band.

[0012] In some embodiments, the refractive surface is any one of a sphere, an aspherical surface, and a freeform surface.

[0013] A second aspect of this application provides an optical system including a combination lens as described in any of the preceding claims.

[0014] A third aspect of this application provides an optical lens, including: an image sensor and the aforementioned optical system, wherein the image sensor is disposed on the image plane of the optical system.

[0015] The combined lens provided in this application includes a lens body and a diffractive optical element. The lens body allows light of the target wavelength to pass through. The lens body includes a refractive surface and a structural surface. The refractive surface is configured to modulate the incident light through refraction, and the structural surface is located on either side of the thickness direction of the lens body. The diffractive optical element is disposed on the structural surface and is configured to modulate the incident light through diffraction. The combined lens provided in this application, comprising a lens body and a diffractive optical element configured to modulate the incident light through diffraction, possesses excellent optical performance due to the high design freedom and good manufacturability of the diffractive optical element. Combined with the light modulation by the refractive surface of the lens body, the combined lens can be widely used in various optical systems. Attached Figure Description

[0016] The above and other objectives, features and advantages of this application will become more apparent from a detailed description of exemplary embodiments thereof with reference to the accompanying drawings.

[0017] Figure 1 A schematic diagram of the combined lens structure is shown in one embodiment of this application.

[0018] Figure 2 A phase distribution diagram of the diffractive optical element of the combined lens in one embodiment of this application is shown.

[0019] Figure 3 A schematic diagram of the combined lens structure is shown in one embodiment of this application.

[0020] Figure 4 A phase distribution diagram of the diffractive optical element of the combined lens in one embodiment of this application is shown.

[0021] Figure 5 A schematic diagram of the combined lens structure is shown in one embodiment of this application.

[0022] Figure 6A phase distribution diagram of the diffractive optical element of the combined lens in one embodiment of this application is shown.

[0023] Figure 7 A schematic diagram of the combined lens structure is shown in one embodiment of this application.

[0024] Figure 8 A phase distribution diagram of the diffractive optical element of the combined lens in one embodiment of this application is shown.

[0025] Figure 9 A schematic diagram of the combined lens structure is shown in one embodiment of this application.

[0026] Figure 10 A phase distribution diagram of the diffractive optical element of the combined lens in one embodiment of this application is shown.

[0027] Figure 11 A schematic diagram of the combined lens structure is shown in one embodiment of this application.

[0028] Figure 12 A phase distribution diagram of the diffractive optical element of the combined lens in one embodiment of this application is shown.

[0029] Figure 13 A schematic diagram of the combined lens structure is shown in one embodiment of this application.

[0030] Figure 14 A schematic diagram of the combined lens structure is shown in one embodiment of this application.

[0031] Figure 15 A phase distribution diagram of the diffractive optical element of the combined lens in one embodiment of this application is shown.

[0032] Figure Labels

[0033] 100. Combination lenses;

[0034] 10. Lens body; 110. Structural surface; 120. Refractive surface;

[0035] 20. Diffractive optical elements. Detailed Implementation

[0036] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, they are provided to make the description of this application more comprehensive and complete, and to fully convey the concept of the exemplary embodiments to those skilled in the art. The drawings are merely illustrative of this application and are not necessarily drawn to scale. The same reference numerals in the drawings denote the same or similar parts, and therefore repeated descriptions of them will be omitted.

[0037] Furthermore, the described features, structures, or characteristics can be combined in any suitable manner in one or more exemplary embodiments. Numerous specific details are provided in the following description to give a full understanding of exemplary embodiments of this application. However, those skilled in the art will recognize that the technical solutions of this application can be practiced by omitting one or more of the specific details, or other modules, components, etc., can be employed. In other instances, well-known structures, methods, implementations, or operations are not shown or described in detail to avoid obscuring various aspects of this application.

[0038] Please see Figure 1 , Figure 1 The diagram shows a structural schematic of a combined lens 100 in one embodiment of this application. The combined lens 100 includes a lens body 10 and a diffractive optical element 20, both of which can modulate incident light.

[0039] The lens body 10 allows light of the target wavelength to pass through; that is, the lens body 10 is a transmissive lens. The lens body 10 includes a refractive surface 120 and a structural surface 110. The refractive surface 120 is located on either side of the thickness direction T of the lens body 10, and the structural surface 110 is located on the opposite side of the refractive surface 120. For example, in… Figure 1 The intermediate refractive surface 120 is located on the right side of the lens body 10 in the thickness direction T, and the structural surface 110 is located on the left side of the lens body 10 in the thickness direction T. The refractive surface 120 has curvature and is configured to modulate incident light through refraction.

[0040] A diffractive optical element (DOE) 20 is an optical device that uses the principle of light diffraction to manipulate the wavefront of light. The diffractive optical element 20 is disposed on the structural surface 110 and is configured to modulate the incident light through diffraction.

[0041] The combined lens 100 provided in this application includes a lens body 10 and a diffractive optical element 20. The diffractive optical element 20 is configured to modulate the incident light through diffraction. Since the diffractive optical element 20 has a high degree of design freedom and good manufacturability, and is combined with the refractive surface 120 of the lens body 10 to modulate the light, the combined lens 100 has excellent optical performance and can be widely used in various optical systems.

[0042] For the composite lens 100, when the structural surface 110 is the surface of the lens body 10 near the image plane, the composite lens 100 includes, along the optical axis from the object plane to the image plane, the lens body 10 and the diffractive optical element 20 in sequence. The incident light is first modulated by the lens body 10, and then by the diffractive optical element 20. When the structural surface 110 is the surface of the lens body 10 near the object plane, the composite lens 100 includes, along the optical axis from the object plane to the image plane, the diffractive optical element 20 and the lens body 10 in sequence. The incident light is first modulated by the diffractive optical element 20, and then by the lens body 10.

[0043] In some embodiments, the combined lens 100 satisfies equation (1):

[0044] 0 < n × |C d |<0.5(1)

[0045] In equation (1), n ​​is the refractive index of the lens body 10, and C d Let be the curvature of the refractive surface 120. Equation (1) reflects the light refraction capability of the refractive surface 120. The lower limit of Equation (1) represents the minimum light refraction capability that the combined lens 100 can provide, and the upper limit of Equation (1) represents the maximum light refraction capability that the combined lens 100 needs to provide based on a certain optical architecture.

[0046] In some embodiments, the combined lens 100 satisfies equation (2):

[0047] 0mm<|f z |<30000mm(2)

[0048] In equation (2), f z Let be the focal length of the combined lens 100. Equation (2) represents the focal length that the combined lens can provide. The lower limit of Equation (2) represents the maximum light refraction capability that the combined lens 100 can provide, and the upper limit of Equation (2) represents the minimum light refraction capability that the combined lens 100 needs to provide based on a certain optical architecture.

[0049] In some embodiments, the combined lens 100 satisfies equation (3):

[0050]

[0051] In equation (3), f m f is the focal length of the diffractive optical element 20. z For a combined lens with a focal length of 100, f m f mThe dimensions are the same, both being units of length, such as millimeters. Equation (3) reflects the focal length proportion undertaken by the diffractive optical element 20 in the combined lens 100, demonstrating the role of the diffractive optical element 20 in focusing. The lower limit of Equation (3) represents the maximum light focusing capability that the diffractive optical element 20 can provide, and the upper limit of Equation (3) represents the minimum light focusing capability required by the diffractive optical element 20 under a certain optical architecture.

[0052] In some embodiments, the combined lens 100 satisfies equation (4):

[0053]

[0054] In equation (4), f d f is the focal length of the lens body 10. z The focal length of the combined lens is 100. d f z The dimensions are the same, both being units of length, such as millimeters. Equation (4) reflects the role of the diffractive optical element 20 in focusing. The lower limit of Equation (4) reflects the maximum light focusing capability that the diffractive optical element 20 can provide, and the upper limit of Equation (4) represents the minimum light focusing capability required by the diffractive optical element 20 based on a certain optical architecture.

[0055] In some embodiments, the diffractive optical element 20 is an independent optical element, that is, the diffractive optical element 20 has a physical structure different from the lens body 10 to achieve its corresponding function. In this case, the diffractive optical element 20 is disposed on the structural surface 110 by bonding it to the lens body 10. For example, when the diffractive optical element 20 is a metasurface, a micro / nano structure can be fabricated based on the surface of the substrate first, and then bonded to the lens body 10 to achieve the placement of the diffractive optical element 20 on the structural surface 110. It is understood that when the diffractive optical element 20 is an independent optical element, the method by which the diffractive optical element 20 is disposed on the structural surface 110 is not limited to bonding, as long as the diffractive optical element 20 can be disposed on the structural surface 110.

[0056] In some embodiments, the diffractive optical element 20 is any one of a metasurface, a Fresnel surface, and a grating surface. The metasurface, Fresnel surface, and grating surface can be fabricated based on the structural surface 110 of the lens body 10 to form the diffractive optical element 20 on the structural surface 110, thereby realizing the placement of the diffractive optical element 20 on the structural surface 110. For example, the structural surface 110 of the lens body 10 can be fabricated using semiconductor processes to obtain a metasurface, a Fresnel surface, or a grating surface on the structural surface 110 of the lens body 10. Please refer to [link to relevant documentation]. Figure 1 , Figure 3 , Figure 7 , Figure 9 , Figure 11, Figure 13 as well as Figure 14 A metasurface can be obtained on the structural surface 110 of the lens body 10 by fabricating a micro / nano structure array on the structural surface 110. Please refer to [link / reference]. Figure 1 , Figure 3 , Figure 7 , Figure 9 , Figure 11 and Figure 13 The micro / nano structure can be a normal micro / nano structure; please refer to [link / reference]. Figure 14 Furthermore, micro / nano structures can also be negative micro / nano structures. It is important to note that... Figure 13 and Figure 14 The combined lens 100 shown has the same optical performance; the only difference between the two is their micro / nano structure. Figure 13 The micro / nano structure in the combined lens 100 shown is a positive micro / nano structure. Figure 14 The micro / nanostructures in the illustrated combined lens 100 are positive micro / nanostructures. That is, when the diffractive optical element 20 is a metasurface, for any shape of diffractive optical element 20, the included micro / nanostructures can be either positive or negative. Therefore, this application does not limit the positive or negative nature of the micro / nanostructures. It is understood that... (Please refer to...) Figure 1 , Figure 3 , Figure 7 , Figure 9 , Figure 11 , Figure 13 as well as Figure 14 The micro- and nanostructures shown are for illustrative purposes only. No restrictions are placed on the positive or negative, shape, or period of the micro- and nanostructures, as long as the selected micro- and nanostructures enable the diffractive optical element 20 to have the expected optical performance.

[0057] When the diffractive optical element 20 is fabricated based on the structural surface 110 of the lens body 10, the combined lens 100 has a smaller thickness, volume, and weight, which is beneficial for reducing the volume of the optical system including the combined lens 100. For example, when an optical system includes a single combined lens 100, if the diffractive optical element 20 is fabricated based on the structural surface 110 of the lens body 10, the optical system has the advantage of a smaller size. Please refer to... Figure 5 A Fresnel surface can be obtained on the structural surface 110 of the lens body 10 by machining a stepped serrated structure (not shown in the figure) on the structural surface 110.

[0058] When the diffractive optical element 20 is a metasurface, the metasurface offers high design freedom. The metasurface exhibits different optical powers at different wavelengths. By rationally configuring the parameters of the micro / nano structure of the superlens and arranging the micro / nano structure appropriately, broadband achromatic light can be achieved. Simultaneously, the optical powers of the combined lens 100 at different wavelengths can be used to correct aberrations in the optical system. Therefore, the combined lens 100 has significant advantages over traditional refractive lenses in terms of size, cost, and optical performance.

[0059] In some embodiments, the target wavelength of the combined lens 100 includes at least one of the visible light band, the near-infrared band, and the far-infrared band, so that the combined lens 100 can be widely used in various optical systems. For example, when the target wavelength of the combined lens 100 is the visible light band, the combined lens 100 can be used in a visible light optical system. For example, when the target wavelength of the combined lens 100 is the far-infrared band, the combined lens 100 can be used in a far-infrared optical system. For example, when the target wavelength of the combined lens 100 is both the visible light band and the near-infrared band, the combined lens 100 can be used in a day-night confocal optical system.

[0060] In some embodiments, the refractive surface 120 is any one of a spherical surface, an aspherical surface, and a freeform surface. When the refractive surface 120 is spherical, the lens body 10 has the advantage of better manufacturability. When the refractive surface 120 is aspherical, the lens body 10 has excellent aberration correction capability. When the refractive surface 120 is a freeform surface, because it breaks rotational symmetry, it can improve the design freedom, aberration correction capability, and off-axis system performance of the combined lens 100.

[0061] This application provides seven exemplary embodiments to illustrate the optical performance of the combined lens 100. The combined lens 100 provided in each embodiment of this application will now be described in detail.

[0062] Example 1

[0063] Figure 1 The combined lens 100 in Embodiment 1 is shown, wherein the working band (i.e., the target band) of the combined lens 100 is the far-infrared band, and the diffractive optical element 20 is a metasurface. The incident light is modulated sequentially by the diffractive optical element 20 and the lens body 10. Some parameters of the combined lens 100 are shown in Table 1-1.

[0064] Table 1-1. Some parameters of combination lens 100

[0065] parameter data focal length 13mm Operating band Far Infrared

[0066] Starting with the diffractive optical element 20, each surface in the combined lens 100 is numbered, and the parameters of each surface are summarized to obtain Table 1-2 below.

[0067] Table 1-2. Parameters of each surface in the combined lens 100 provided in Example 1

[0068] Surface serial number Surface type Radius of curvature (mm) Thickness (mm) Material 1 metasurface unlimited 0.3 silicon 2 aspherical -32.9 - -

[0069] Since the metasurface is disposed on the structural surface 110 of the lens body 10, the structural surface 110 on which the metasurface is disposed is referred to as the metasurface in Table 1-2. As can be seen from Table 1-2, surface 1 is a metasurface, surface 2 is an aspherical surface, the distance between surface 1 and surface 2 is 0.3 mm, and the material between surface 1 and surface 2 is silicon.

[0070] Surface 2 is an even-order aspherical surface, and its surface shape satisfies the following formula for an even-order aspherical surface:

[0071]

[0072] Where Z(r) is the distance vector from the vertex of the aspherical surface at a height of r along the optical axis 90°; c is the surface curvature of the aspherical surface, c = 1 / R, where R is the radius of curvature of the aspherical surface; K is the conic coefficient; A, B, C, D... are aspherical coefficients. The values ​​of K, A, B, C, D... for surface 2 can be obtained from Table 1-3.

[0073] Table 1-3. Coefficients of even-order aspherical surfaces in the combined lens 100 provided in Example 1

[0074]

[0075] Please see Figure 2 , Figure 2 A phase distribution diagram of the metasurface of the combined lens provided in Embodiment 1 is shown. Figure 2 The horizontal axis represents the radial distance from the center of the metasurface, in millimeters; Figure 2 The vertical axis represents the phase, with units of 2π rad. It is important to note that... Figure 2 The actual phase distribution of the metasurface is given. Since the phase is a periodic function of 2π, the following relationship exists: (n is an integer, therefore, it can be based on the needs.) Figure 2 The phase of the metasurface in Example 1 is normalized by taking the remainder of 2π to meet the needs of actual metasurface processing.

[0076] Example 2

[0077] Figure 3The combined lens 100 in Embodiment 2 is shown, wherein the operating wavelength of the combined lens 100 is the visible light band, and the diffractive optical element 20 is a metasurface. The incident light is modulated sequentially by the diffractive optical element 20 and the lens body 10. Some parameters of the combined lens 100 are shown in Table 2-1.

[0078] Table 2-1. Some parameters of combination lens 100

[0079] parameter data focal length 8.7mm Operating band Visible light

[0080] Starting with the diffractive optical element 20, each surface in the combined lens 100 is numbered, and the parameters of each surface are summarized to obtain Table 2-2 below.

[0081] Table 2-2. Parameters of each surface in the combined lens 100 provided in Example 2

[0082] Surface serial number Surface type Radius of curvature (mm) Thickness (mm) Material 1 metasurface unlimited 0.23 silicon dioxide 2 aspherical -5.8 - -

[0083] The analysis of each surface in Table 2-2 can be referred to Example 1, and will not be repeated in this example.

[0084] Surface 2 is an even-order aspherical surface, and its surface shape satisfies the above formula for even-order aspherical surfaces. The values ​​of K, A, B, C, D... of surface 2 can be obtained from Table 2-3.

[0085] Table 2-3. Coefficients of even-order aspherical surfaces in the combined lens 100 provided in Example 2

[0086]

[0087] Please see Figure 4 , Figure 4 A phase distribution diagram of the metasurface of the combined lens provided in Example 2 is shown. Figure 4 The horizontal axis represents the radial distance from the center of the metasurface, in millimeters; Figure 4 The vertical axis represents the phase, with units of 2π rad. It is important to note that... Figure 4 The given value is the actual phase distribution of the metasurface, which can be adjusted as needed based on... Figure 4 The phase of the metasurface in Example 2 is normalized by taking the remainder of 2π to meet the needs of actual metasurface processing.

[0088] Example 3

[0089] Figure 5 The combined lens 100 in Embodiment 3 is shown, wherein the operating wavelength of the combined lens 100 is the far-infrared band, and the diffractive optical element 20 is a Fresnel surface. The incident light is modulated sequentially by the diffractive optical element 20 and the lens body 10. Some parameters of the combined lens 100 are shown in Table 3-1.

[0090] Table 3-1. Some parameters of combination lens 100

[0091] parameter data focal length 14mm Operating band Far Infrared

[0092] Starting with the diffractive optical element 20, each surface in the combined lens 100 is numbered, and the parameters of each surface are summarized to obtain Table 3-2 below.

[0093] Table 3-2. Parameters of each surface in the combined lens 100 provided in Example 3

[0094] Surface serial number Surface type Radius of curvature (mm) Thickness (mm) Material 1 Fresnel noodles unlimited 0.5 IRG206 2 aspherical -138.3 - -

[0095] The analysis of each surface in Table 3-2 can be referred to Example 1, and will not be repeated in this example.

[0096] Surface 2 is an even-order aspherical surface, and its surface shape satisfies the above formula for even-order aspherical surfaces. The values ​​of K, A, B, C, D... of surface 2 can be obtained from Table 3-3.

[0097] Table 3-3. Coefficients of even-order aspherical surfaces in the combined lens 100 provided in Example 3

[0098]

[0099] Please see Figure 6 , Figure 6 A phase distribution diagram of the metasurface of the combined lens provided in Example 3 is shown. Figure 6 The horizontal axis represents the radial distance from the center of the metasurface, in millimeters; Figure 6 The vertical axis represents the phase, with units of 2π rad. It is important to note that... Figure 6 The given value is the actual phase distribution of the Fresnel surface, which can be adjusted as needed based on... Figure 6 The phase of the Fresnel surface in Example 3 is normalized by taking the remainder of 2π to meet the needs of actual metasurface processing.

[0100] Example 4

[0101] Figure 7 The combined lens 100 in Embodiment 4 is shown, wherein the operating wavelength of the combined lens 100 is the far-infrared band, and the diffractive optical element 20 is a metasurface. The incident light is modulated sequentially by the diffractive optical element 20 and the lens body 10. Some parameters of the combined lens 100 are shown in Table 4-1.

[0102] Table 4-1. Some parameters of combination lens 100

[0103] parameter data focal length -4.3mm Operating band Far Infrared

[0104] Starting with the diffractive optical element 20, each surface in the combined lens 100 is numbered, and the parameters of each surface are summarized to obtain Table 4-2 below.

[0105] Table 4-2. Parameters of each surface in the combined lens 100 provided in Example 4

[0106] Surface serial number Surface type Radius of curvature (mm) Thickness (mm) Material 1 metasurface unlimited 0.2 germanium 2 aspherical 28.3 - -

[0107] The analysis of each surface in Table 4-2 can be referred to Example 1, and will not be repeated in this example.

[0108] Surface 2 is an even-order aspherical surface, and its surface shape satisfies the above formula for even-order aspherical surfaces. The values ​​of K, A, B, C, D... of surface 2 can be obtained from Table 4-3.

[0109] Table 4-3. Coefficients of even-order aspherical surfaces in the combined lens 100 provided in Example 4

[0110]

[0111] Please see Figure 8 , Figure 8 A phase distribution diagram of the metasurface of the combined lens provided in Example 2 is shown. Figure 8 The horizontal axis represents the radial distance from the center of the metasurface, in millimeters; Figure 8 The vertical axis represents the phase, with units of 2π rad. It is important to note that... Figure 8 The given value is the actual phase distribution of the metasurface, which can be adjusted as needed based on... Figure 8 The phase of the metasurface in Example 2 is normalized by taking the remainder of 2π to meet the needs of actual metasurface processing.

[0112] Example 5

[0113] Figure 9 The combined lens 100 in Embodiment 5 is shown, wherein the operating wavelength of the combined lens 100 is the far-infrared band, and the diffractive optical element 20 is a metasurface. The incident light is modulated sequentially by the diffractive optical element 20 and the lens body 10. Some parameters of the combined lens 100 are shown in Table 5-1.

[0114] Table 5-1. Some parameters of combination lens 100

[0115]

[0116]

[0117] Starting with the diffractive optical element 20, each surface in the combined lens 100 is numbered, and the parameters of each surface are summarized to obtain Table 5-2 below.

[0118] Table 5-2. Parameters of each surface in the combined lens 100 provided in Example 5

[0119] Surface serial number Surface type Radius of curvature (mm) Thickness (mm) Material 1 metasurface unlimited 0.6 germanium 2 aspherical -16 - -

[0120] The analysis of each surface in Table 5-2 can be referred to Example 1, and will not be repeated in this example.

[0121] Surface 2 is an even-order aspherical surface, and its surface shape satisfies the above formula for even-order aspherical surfaces. The values ​​of K, A, B, C, D... of surface 2 can be found in Table 5-3.

[0122] Table 5-3. Coefficients of even-order aspherical surfaces in the combined lens 100 provided in Example 5

[0123]

[0124] Please see Figure 10 , Figure 10 A phase distribution diagram of the metasurface of the combined lens provided in Example 5 is shown. Figure 10 The horizontal axis represents the radial distance from the center of the metasurface, in millimeters; Figure 10 The vertical axis represents the phase, with units of 2π rad. It is important to note that... Figure 10 The given value is the actual phase distribution of the metasurface, which can be adjusted as needed based on... Figure 10 The phase of the metasurface in Example 5 is normalized by taking the remainder of 2π to meet the needs of actual metasurface processing.

[0125] Example 6

[0126] Figure 11 The combined lens 100 in Embodiment 6 is shown, wherein the working band (i.e., the target band) of the combined lens 100 is the far-infrared band, and the diffractive optical element 20 is a metasurface. The incident light is modulated sequentially by the diffractive optical element 20 and the lens body 10. Some parameters of the combined lens 100 are shown in Table 6-1.

[0127] Table 6-1. Some parameters of combination lens 100

[0128] parameter data focal length -382.2mm Operating band Far Infrared

[0129] Starting with the diffractive optical element 20, each surface in the combined lens 100 is numbered, and the parameters of each surface are summarized to obtain Table 6-2 below.

[0130] Table 6-2. Parameters of each surface in the combined lens 100 provided in Example 6

[0131]

[0132]

[0133] The analysis of each surface in Table 6-2 can be referred to Example 1, and will not be repeated in this example.

[0134] Surface 2 is an even-order aspherical surface, and its surface shape satisfies the above formula for even-order aspherical surfaces. The values ​​of K, A, B, C, D... of surface 2 can be obtained from Table 6-3.

[0135] Table 6-3. Coefficients of even-order aspherical surfaces in the combined lens 100 provided in Example 6

[0136]

[0137] Please see Figure 12 , Figure 12 A phase distribution diagram of the metasurface of the combined lens provided in Example 6 is shown. Figure 12 The horizontal axis represents the radial distance from the center of the metasurface, in millimeters; Figure 12 The vertical axis represents the phase, with units of 2π rad. It is important to note that... Figure 12 The given value is the actual phase distribution of the metasurface, which can be adjusted as needed based on... Figure 12 The phase of the metasurface in Example 6 is normalized by taking the remainder of 2π to meet the needs of actual metasurface processing.

[0138] Example 7

[0139] Figure 13 or Figure 14 The combined lens 100 in Embodiment 7 is shown, due to Figure 13 and Figure 14 The combined lens 100 shown has the same optical performance; the only difference between the two is their micro / nano structure. Therefore, this embodiment uses... Figure 13 Let's take the example of combination lens 100 to further illustrate... Figure 14 The description of the combined lens 100 shown below can be found in the following text. Figure 13 The example provided will not be repeated here.

[0140] Please see Figure 13 The working band (i.e., the target band) of the combined lens 100 is the far-infrared band, and the diffractive optical element 20 is a metasurface. The incident light is modulated sequentially by the diffractive optical element 20 and the lens body 10. Some parameters of the combined lens 100 are shown in Table 7-1.

[0141] Table 7-1. Some parameters of combination lens 100

[0142] parameter data focal length -18485.1mm Operating band Far Infrared

[0143] Starting with the diffractive optical element 20, each surface in the combined lens 100 is numbered, and the parameters of each surface are summarized to obtain Table 7-2 below.

[0144] Table 7-2. Parameters of each surface in the combined lens 100 provided in Example 1

[0145] Surface serial number Surface type Radius of curvature (mm) Thickness (mm) Material 1 metasurface unlimited 3 silicon 2 aspherical -1.6e8 - -

[0146] The analysis of each surface in Table 7-2 can be referred to Example 1, and will not be repeated in this example.

[0147] Surface 2 is an even-order aspherical surface, and its surface shape satisfies the above formula for even-order aspherical surfaces. The values ​​of K, A, B, C, D... of surface 2 can be obtained from Table 7-3.

[0148] Table 7-3. Coefficients of even-order aspherical surfaces in the combined lens 100 provided in Example 7

[0149]

[0150] Please see Figure 14 , Figure 14 A phase distribution diagram of the metasurface of the combined lens provided in Embodiment 7 is shown. Figure 14 The horizontal axis represents the radial distance from the center of the metasurface, in millimeters; Figure 14 The vertical axis represents the phase, with units of 2π rad. It is important to note that... Figure 14 The actual phase distribution of the metasurface is given. Since the phase is a periodic function of 2π, the following relationship exists: (n is an integer, therefore, it can be based on the needs.) Figure 14 The phase of the metasurface in Example 7 is normalized by taking the remainder of 2π to meet the needs of actual metasurface processing.

[0151] After summarizing the parameters of the combined lens 100 provided in the above 7 embodiments, the following table 8 is obtained.

[0152] Table 8. Parameters of the combined lens 100 provided in each embodiment

[0153]

[0154] This application also provides an optical system (not shown), which includes the above-described combined lens 100, and the operating wavelength of the optical system depends on the operating wavelength of the combined lens 100.

[0155] This application also provides an optical lens (not shown), which includes an image sensor and the aforementioned optical system. The image sensor is located on the image plane of the optical system, and the image sensor includes, but is not limited to, CMOS (Complementary Metal Oxide Semiconductor) and CCD (Charge Coupled Device).

[0156] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the utility models disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the appended claims.

Claims

1. A combination lens, characterized in that, The combined lens includes: The lens body allows light of the target wavelength to pass through; the lens body includes a refractive surface and a structural surface, the refractive surface being configured to modulate incident light through refraction, and the structural surface being located on any side of the thickness direction of the lens body; A diffractive optical element is disposed on the structural surface, and the diffractive optical element is configured to modulate the incident light through diffraction.

2. The combined lens according to claim 1, characterized in that, The combined lens satisfies: 0 < n × |C d |<0.5, where n is the refractive index of the lens body, C d Let be the curvature of the refracting surface.

3. The combined lens according to claim 1, characterized in that, The combined lens satisfies: 0mm < |f z |<30000mm, where, f z is the focal length of the combined lens.

4. The combined lens according to claim 1, characterized in that, The combined lens meets the following requirements: Among them, f m f is the focal length of the diffractive optical element. z is the focal length of the combined lens.

5. The combined lens according to claim 1, characterized in that, The combined lens meets the following requirements: Among them, f d f is the focal length of the lens body. z is the focal length of the combined lens.

6. The combined lens according to claim 1, characterized in that, The diffractive optical element is any one of a metasurface, a Fresnel surface, or a grating surface.

7. The combined lens according to claim 1, characterized in that, The target band includes at least one of the visible light band, the near-infrared band, and the far-infrared band.

8. The combined lens according to claim 1, characterized in that, The refractive surface can be any one of a sphere, an aspherical surface, or a freeform surface.

9. An optical system, characterized in that, Includes the combination lens as described in any one of claims 1-8.

10. An optical lens, characterized in that, include: An image sensor and an optical system as claimed in claim 9, wherein the image sensor is disposed on the image plane of the optical system.

Images