Optical scanning module and optical scanning device

Abstract

The present invention proposes an optical scanning module comprising: a lens body having a first surface and a second surface disposed opposite to each other, the first surface outputting light and the second surface receiving light; a nanostructure array including a plurality of nanostructures and disposed on the first surface; and a photosensitive pixel disposed facing the first surface and including a first photosensitive sub-pixel, a second photosensitive sub-pixel, and a third photosensitive sub-pixel, wherein the nanostructure array deflects a portion of red light propagating in the lens body to the first photosensitive sub-pixel, a portion of green light propagating in the lens body to the second photosensitive sub-pixel, and a portion of blue light propagating in the lens body to the third photosensitive sub-pixel.

Description

Optical scanning module The present invention relates to an optical scanning module, and more particularly to an optical scanning module capable of simultaneously scanning multiple colors by disposing a super lens structure on the light emitting surface of a lens body. Common scanners on the market, such as file scanners and printers with built-in scanning functions, use linear scanners for scanning. However, the internal design of these scanners typically allows only single-wavelength images to be recorded in a single pass. To record a color image, multiple exposures are required. Therefore, it is necessary to provide an optical scanning module capable of scanning multiple colors simultaneously to overcome the above problems. In order to effectively solve the above-mentioned problems, the present invention proposes an optical scanning module, comprising: a lens body having a first surface and a second surface arranged opposite to each other, the first surface outputting light and the second surface receiving light; a nanostructure array including a plurality of nanostructures and arranged on the first surface; and a photosensitive pixel arranged to face the first surface and including a first photosensitive sub-pixel, a second photosensitive sub-pixel, and a third photosensitive sub-pixel, wherein the nanostructure array deflects a portion of red light propagating in the lens body to the first photosensitive sub-pixel, deflects a portion of green light propagating in the lens body to the second photosensitive sub-pixel, and deflects a portion of blue light propagating in the lens body to the third photosensitive sub-pixel. Preferably, the scanning module further comprises a light source, providing white light with circular polarization to scan an object, wherein the reflected light of the object is transmitted to the photosensitive pixel through the lens body. Preferably, each of the plurality of nanostructures is a rectangular columnar nanostructure, and the length and width of each nanostructure are configured as a function of the coordinates on the first surface. Preferably, each of the plurality of nanostructures is a rectangular columnar nanostructure, and the length, width, and height of each nanostructure are configured as a function of coordinates on the first surface. Preferably, each of the plurality of nanostructures is a rectangular columnar nanostructure having an optical fast axis defining an azimuth angle of the rectangular columnar nanostructure, wherein the azimuth angle is configured as a function of a coordinate on the first surface. Preferably, the plurality of nanostructures include: a plurality of first nanostructures configured to deflect red light to the first photosensitive sub-pixel; a plurality of second nanostructures configured to deflect green light to the second photosensitive sub-pixel; and a plurality of third nanostructures configured to deflect blue light to the third photosensitive sub-pixel. Preferably, the plurality of first nanostructures, the plurality of second nanostructures, and the plurality of third nanostructures are substantially uniformly distributed on the first surface. Preferably, the plurality of first nanostructures, the plurality of second nanostructures, and the plurality of third nanostructures are periodically disposed on the first surface in a subset manner according to a ratio of their numbers. Preferably, the ratio of the number of the plurality of first nanostructures, the number of the plurality of second nanostructures, and the number of the plurality of third nanostructures is 1:1:1. Preferably, the plurality of nanostructures are periodically arranged on the first surface in the form of a first nanostructure, a second nanostructure, and a third nanostructure as a group, and a period of the plurality of nanostructures is a constant. Preferably, the ratio of the number of the plurality of first nanostructures, the number of the plurality of second nanostructures, and the number of the plurality of third nanostructures is 2:1:3. Preferably, the plurality of nanostructures are periodically arranged on the first surface in the form of a group of two first nanostructures, one second nanostructure, and three third nanostructures, and a period of the plurality of nanostructures is a constant. Preferably, the optical scanning module further comprises: a red filter disposed on the first photosensitive sub-pixel; a green filter disposed on the second photosensitive sub-pixel; and a blue filter disposed on the third photosensitive sub-pixel. Preferably, the optical scanning module further comprises: a light source providing white light for scanning an object, wherein the reflected light of the object is incident on the second surface. According to another aspect of the present invention, an optical scanning device is provided, comprising: a plurality of the aforementioned optical scanning modules arranged in a row; and a light source providing white light for scanning an object. In order to enable those skilled in the art to understand the purpose, features and effects of the present invention, the present invention is described in detail below through the following specific embodiments and in conjunction with the accompanying drawings. The present invention will now be described more fully below with reference to the accompanying drawings in which exemplary embodiments of the present invention are shown. The advantages and features of the present invention and how they are achieved will become apparent from the exemplary embodiments described below in more detail with reference to the accompanying drawings. However, it should be noted that the present invention is not limited to the following exemplary embodiments, but can be implemented in various forms. Therefore, the exemplary embodiments are provided only to disclose the present invention and to enable those skilled in the art to understand the categories of the present invention. In the drawings, exemplary embodiments of the present invention are not limited to the specific examples provided herein and are exaggerated for clarity. The terms used herein are intended only to illustrate specific embodiments and are not intended to limit the present invention. Unless the context clearly indicates otherwise, the singular forms of the terms "a," "an," and "the" used herein are intended to include the plural forms as well. The terms "and / or" used herein include any and all combinations of one or more of the relevant listed items. It should be understood that when an element is said to be "connected" or "coupled" to another element, the element may be directly connected or coupled to the other element or there may be intermediate elements. Similarly, it should be understood that when an element (such as a layer, region, or substrate) is referred to as being "on" another element, the element can be directly on the other element or intervening elements may be present. In contrast, the term "directly" means that there are no intervening elements. It should be further understood that when the terms "include" and "comprising" are used herein, they indicate the presence of stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. Furthermore, exemplary embodiments in the detailed description will be described using cross-sectional views that serve as idealized exemplary diagrams of the present invention. Accordingly, the shapes of the exemplary diagrams may be modified based on manufacturing techniques and / or tolerable errors. Therefore, exemplary embodiments of the present invention are not limited to the specific shapes shown in the exemplary diagrams, but may include other shapes that may be produced based on manufacturing processes. The regions illustrated in the drawings are general in nature and are used to illustrate specific shapes of components. Therefore, this should not be considered as limiting the scope of the present invention. It should also be understood that although the terms "first," "second," "third," etc. may be used herein to describe various elements, these elements should not be limited to these terms. These terms are merely used to distinguish between the various elements. Thus, a first element in some embodiments may be referred to as a second element in other embodiments without departing from the teachings of the present invention. The exemplary embodiments of the aspects of the inventive concepts illustrated and described herein include their complementary counterparts. Throughout this specification, the same element number or the same indicator represents the same element. Furthermore, while exemplary embodiments are described herein with reference to cross-sectional and / or plan views, such cross-sectional and / or plan views are idealized, exemplary illustrations. Therefore, deviations from the illustrated shapes due to, for example, manufacturing techniques and / or tolerances are to be expected. Therefore, exemplary embodiments should not be considered limited to the shapes of regions illustrated herein, but are intended to encompass deviations in shape due to, for example, manufacturing. Therefore, the regions illustrated in the figures are schematic, and their shapes are not intended to illustrate the actual shape of a region of a device or to limit the scope of exemplary embodiments. Please refer to Figure 1. Figure 1 is a schematic diagram showing the lens structure of a conventional optical scanning module according to prior art. A conventional optical scanning module may include a lens array consisting of a plurality of lenses 10 and a linear sensor consisting of a plurality of photosensitive pixels P, arranged in a corresponding row. That is, one lens corresponds to one photosensitive element. Reflected light from the scanned object is guided by the lens body 11 of the lens 10 to the output surface 11', generating output light 20. The output light 20 propagates to the corresponding photosensitive pixel P to sense its light intensity. When the scanning light source is white light, grayscale scanning can be performed, recording the grayscale distribution regardless of color. However, for color scanning, red, green, and blue light must be repeatedly used in sequence for scanning and sensing. To avoid repeated exposure sampling and achieve simultaneous multi-color scanning sensing, the optical scanning module of the present invention specifically utilizes a meta-lens structure, which can split the full-wavelength light beam emitted from the refractive lens. This structure can be formed by fabricating nanoscale geometric structures on a substrate material. Nanoscale geometric structures can control the transmission, refraction, polarization, phase, and other properties of light passing through the nanoscale geometric structures based on their physical properties, such as length, width, height, diameter, and orientation. In some embodiments, the meta-lens can be manufactured using techniques such as electron beam (e-beam) lithography. Please refer to Figures 2 to 4. Figure 2 is a schematic diagram showing the structure of an optical scanning module according to one embodiment of the present invention; Figure 3 is a schematic diagram showing a nanostructure array according to one embodiment of the present invention; and Figure 4 is a schematic diagram showing the configuration of a nanostructure array according to one embodiment of the present invention. According to an embodiment of the present invention, the optical scanning module of the present invention may include a plurality of lenses 100 and a corresponding plurality of photosensitive pixels P, which are arranged in a row. Specifically, the lens 100 of the present invention may include a lens body 110 and a nanostructure array 120. The lens body 110 may be made of a transparent material such as glass or sapphire into a round rod-shaped structure. In other words, the lens body 110 of the present invention may be a round rod lens. The lens body 110 of the present invention is made of glass, and a round rod lens is used as an example. Its cross-section is circular. The lens body 110 of the present invention has two opposing ends, a first surface 110' and a second surface (not shown). The first surface 110' and the second surface face each other, and the first surface 110' is used to output light, while the second surface is used to receive light. For example, reflected light from an object to be scanned (e.g., a paper with a colored pattern) may be incident through the second surface of the lens body 110, conducted through the lens body 110, and output from the first surface 110' of the lens body 110 to the photosensitive pixels P, causing the photosensitive pixels P to be sensitive to light to generate photosensitive signals. The photosensitive pixels P may be arranged to face the first surface 110' of the lens body 110, be close to the first surface 110' of the lens body 110, and be away from the second surface of the lens body 110. The nanostructure array 120 of the lens 100 of the present invention can be disposed on the first surface 110' of the lens body 110. The nanostructure array 120 is an array of meta-lens elements, and the first surface 110' provided with the nanostructure array 120 can also be called a meta-surface. The nanostructure array 120 can have a plurality of nanostructures 122 made of meta-material, as shown in FIG3 . The material of the nanostructure 122 can be the same as or different from the material of the lens body 110. For example, the material of the nanostructure 122 can be glass, sapphire, titanium dioxide (TiO 2) Transparent materials. Titanium dioxide is used as an example of the material of the nanostructure 122 of the present invention. Each of the plurality of nanostructures 122 of the present invention may be designed as a columnar nanostructure having a rectangular, circular, L-shaped, T-shaped, I-shaped, or any other cross-section, but is not limited thereto. According to an embodiment of the present invention, each of the plurality of nanostructures 122 can be designed as a rectangular columnar nanostructure having physical characteristics such as coordinates, length, width, height, and a fast axis. The fast axis of the rectangular columnar nanostructure is directional, and the angle between it and a specific axis can be defined as the azimuth angle of the fast axis. For example, the first surface 110' of the lens body 110 can be defined as an xy plane. The coordinates of the rectangular columnar nanostructure can be defined as (x, y), the angle θ between the fast axis and the x-axis can be defined as the azimuth angle θ of the fast axis, and its length, width, and height can be represented by L, W, and H. The physical characteristics of the above-mentioned rectangular columnar nanostructure will be further described later. According to an embodiment of the present invention, the size range of the rectangular columnar nanostructures can be configured to be between 50 nm and 500 nm; preferably, between 100 nm and 400 nm; and more preferably, between 150 nm and 300 nm. Appropriately reducing the size range can effectively improve the process efficiency and yield of the nanostructure array 120. According to an embodiment of the present invention, as shown in FIG2 , a photosensitive pixel P may include a first photosensitive sub-pixel SP1, a second photosensitive sub-pixel SP2, and a third photosensitive sub-pixel SP3, each configured to sense red light, green light, and blue light, respectively. In other words, one lens 100 of the present invention corresponds to three photosensitive elements, unlike conventional techniques where one lens 10 corresponds to one photosensitive element. According to an embodiment of the present invention, the nanostructure array 120 of the lens 100 can simultaneously deflect (and even further focus) a portion of the red light propagating through the lens body 110 toward the first photosensitive sub-pixel SP1, deflect (and even further focus) a portion of the green light propagating through the lens body 110 toward the second photosensitive sub-pixel SP2, and deflect (and even further focus) a portion of the blue light propagating through the lens body 110 toward the third photosensitive sub-pixel SP3. This enables simultaneous sensing and capture of multi-color light signals. According to an embodiment of the present invention, as shown in FIG4 , the plurality of nanostructures 122 may include a plurality of first nanostructures 122R, a plurality of second nanostructures 122B, and a plurality of third nanostructures 122G. The plurality of first nanostructures 122R, the plurality of second nanostructures 122B, and the plurality of third nanostructures 122G may be periodically and repeatedly arranged on the first surface 110 ′ of the lens body 110 , with one first nanostructure 122R, one second nanostructure 122B, and one third nanostructure 122G forming a group. According to an embodiment of the present invention, the plurality of nanostructures 122 may have a constant period or interval. According to an embodiment of the present invention, the plurality of first nanostructures 122R among the plurality of nanostructures 122 may be configured to deflect (or refract) red light toward the first photosensitive sub-pixel SP1 in the photosensitive pixel P; the plurality of second nanostructures 122G among the plurality of nanostructures 122 may be configured to deflect (or refract) and focus green light toward the second photosensitive sub-pixel SP2 in the photosensitive pixel P; and the plurality of third nanostructures 122B among the plurality of nanostructures 122 may be configured to deflect (or refract) blue light toward the third photosensitive sub-pixel SP3 in the photosensitive pixel P. In other words, the plurality of nanostructures 122 including the plurality of first nanostructures 122R, the plurality of second nanostructures 122B, and the plurality of third nanostructures 122G may deflect portions of red light, green light, and blue light toward the corresponding first photosensitive sub-pixel SP1, second photosensitive sub-pixel SP2, and third photosensitive sub-pixel SP3, respectively. To achieve the aforementioned light-splitting and deflection effect of the plurality of nanostructures 122 , the coordinates, shape (length, width, and height), and orientation (fast axis angle) of each of the plurality of nanostructures 122 as well as the period (interval or pitch) of the plurality of nanostructures 122 must be considered. The plurality of nanostructures 122 of the present invention are exemplified by rectangular columnar nanostructures. To achieve the aforementioned effect of enabling the nanostructure array 120 of the lens 100 to simultaneously deflect a portion of red light transmitted through the lens body 110 at the first photosensitive sub-pixel SP1, a portion of green light transmitted through the lens body 110 at the second photosensitive sub-pixel SP2, and a portion of blue light transmitted through the lens body 110 at the third photosensitive sub-pixel SP3, the length, width, height, orientation, and / or period of the rectangular columnar nanostructures must be considered. In other words, when rectangular columnar nanostructures are employed, the design of the nanostructure array 120 must take into account one or a combination of the physical characteristics of the rectangular columnar nanostructures, such as their length, width, height, orientation, and period. The following briefly describes the optical principles of the present invention. The phenomenon of light being deflected by refraction when passing through an object can be represented by the Jones matrix. The Jones matrix for the rectangular columnar nanostructure of the present invention can be expressed as: , (1) where, is a 2×2 rotation matrix; is the azimuthal angle of the fast axis as it changes with spatial position; 、 are the transmission coefficients of two orthogonal linearly polarized lights when they are parallel and perpendicular to the fast axis of the rectangular columnar nanostructure, is their phase difference, wherein the xy plane in the spatial coordinate can be defined as being parallel to the first surface 110 ′ of the lens body 110 , and the length and width of the rectangular columnar nanostructure fall on the xy plane, and its height direction is parallel to the z axis. When a beam of circularly polarized light is incident on the rectangular columnar nanostructure on the first surface 110' (metasurface) of the lens body 110, the outgoing light It can be expressed as: , (2) where, , The first term in formula (2) has the same polarization direction as the incident light, and the coefficient Represents the same polarization efficiency; the second term is orthogonal to the incident polarization direction, the coefficient represents the orthogonal polarization conversion efficiency. Thus, the azimuth angle of the rectangular columnar nanostructure can be rotated Realize the beam from 0 to 2 In other words, the present invention can control the phase difference of light caused by each rectangular columnar nanostructure by designing the azimuth angle of each of the plurality of rectangular columnar nanostructures in the nanostructure array 120 on the first surface 110 ′ of the lens body 110 . According to an embodiment of the present invention, the xy plane in spatial coordinates can be defined as being parallel to the first surface 110' of the lens body 110, and the z-axis is parallel to the height direction of the rectangular columnar nanostructure (or the axial direction of the lens body 110). The first surface 110' of the lens body 110 and the photosensitive pixel P are separated and face each other in the z-axis direction. When the first photosensitive sub-pixel SP1, the second photosensitive sub-pixel SP2, and the third photosensitive sub-pixel SP3 in the photosensitive pixel P are arranged along the x-axis, the phase difference required to deflect light can be calculated using the following formula: , (3) where 、 are the refractive indices on the transmission and incident sides, respectively; 、 are the angle of refraction and the angle of incidence respectively; is the wavelength; for The amount of change in direction; Indicates the phase difference required for that position. In addition, the relationship between the height and phase difference of the rectangular columnar nanostructure is as follows: , (4) where is the phase difference caused by the height of the nanounit column; is the wavelength of light; is the refractive index of the nanometer unit column; H is the height of the nanometer unit column. Satisfy at least The range of change should be . Taking an xz cross-section as an example, the x-axis represents the arrangement direction of the first photosensitive sub-pixel SP1, the second photosensitive sub-pixel SP2, and the third photosensitive sub-pixel SP3, and the z-axis represents the spacing between the first surface 110' of the lens body 110 and the photosensitive pixel P. Each of the plurality of rectangular columnar nanostructures in the nanostructure array 120 on the first surface 110' of the lens body 110 may have its own x-coordinate value and a fixed z-coordinate value (sharing the same z-axis position). Based on the above formula, the phase difference required to deflect light (red light, green light, or blue light) toward the corresponding photosensitive sub-pixel can be calculated. The length, width, and height of the columnar nanostructures corresponding to different phase differences can be retrieved by computer calculation in a database, as shown in FIG5 . FIG5 illustrates the phase difference corresponding to length and width as an example, but is not limited to this embodiment. Through computer search and comparison, the length, width, and height of each of the plurality of rectangular columnar nanostructures on the first surface 110' of the lens body 110 can be obtained, serving as a basis for the design of the rectangular columnar nanostructure at each location. In other words, the length, width, and height of the rectangular columnar nanostructure can vary depending on its position coordinates on the first surface 110' of the lens body 110. In other words, the length, width, and height of the rectangular columnar nanostructure are functions of its position coordinates (xy coordinates). According to an embodiment of the present invention, the height of the rectangular columnar nanostructure can be a fixed value, and the length and width of the rectangular columnar nanostructure can be functions of its position coordinates. A database on the relationship between the phase difference of light and the dimensions (length, width, height) of rectangular columnar nanostructures can be further established based on the following formula. The expression of the electromagnetic wave (light wave) before and after the metasurface (nanostructure array 120) is: , (5) Among them, is the wave number, is the dielectric impedance, r and t are the reflection coefficient and transmission coefficient respectively. Combined with the boundary conditions: , , (6) Among them, is the surface induced current introduced by the metasurface. Assuming that the metasurface unit area is A, the electric susceptibility is α, and only the effect of the electric dipole moment is considered, then: , (7) Among them, . Arranging the above formula, we can get: , (8) Among them, From equation (8), we can see that the transmission coefficient and reflection coefficient of light are affected by the polarizability of the metasurface, which in turn depends on parameters such as the material and dimensions of the rectangular columnar nanostructure. By inputting these parameters into the calculation, we can construct the above-mentioned database on the relationship between the phase difference of light and the dimensions of the rectangular columnar nanostructure. By changing these parameters, the transmission and reflection of light can be controlled. Similarly, to achieve a desired light deflection angle, the azimuth angles of the rectangular columnar nanostructures in the nanostructure array 120 on the first surface 110' of the lens body 110 of the present invention can be arranged to vary with their position coordinates on the first surface 110' of the lens body 110. That is, the azimuth angles of the rectangular columnar nanostructures are a function of their position coordinates (xy coordinates) (as shown in FIG6). Furthermore, any combination of physical quantities such as the length, width, height, and azimuth angle of the rectangular columnar nanostructures in the nanostructure array 120 on the first surface 110' of the lens body 110 of the present invention can be configured to vary along with their position coordinates on the first surface 110' of the lens body 110. That is, any combination of physical quantities such as the length, width, height, and azimuth angle of the rectangular columnar nanostructures is a function of their position coordinates (xy coordinates). According to an embodiment of the present invention, any combination of physical quantities such as the length, width, and azimuth angle of the rectangular columnar nanostructures in the nanostructure array 120 on the first surface 110' of the lens body 110 of the present invention can be configured to vary along with their position coordinates on the first surface 110' of the lens body 110. That is, any combination of physical quantities such as the length, width, and azimuth angle of the rectangular columnar nanostructures is a function of their position coordinates (xy coordinates). In addition, in order to match the lens body 110 of the optical scanning module, the period of the rectangular columnar nanostructure cannot be greater than the minimum resolution distance of the lens body 110, as expressed by the following inequality: , (9) , where d is the minimum resolution distance of the lens body 110; p is the period of the rectangular columnar nanostructure; is the wavelength of light; NA is the numerical aperture of the lens body 110; is the refractive index of the focusing space; D is the diameter of the lens body 110, and f is the focal length of the lens body 110. When selecting the period of the rectangular columnar nanostructure, the minimum wavelength should be used as a reference. Therefore, according to various embodiments of the present invention, the optical scanning module of the present invention achieves the effect of deflecting and guiding (or even focusing) red light, green light, and blue light to the corresponding first photosensitive sub-pixel SP1, second photosensitive sub-pixel SP2, and third photosensitive sub-pixel SP3 by individually or collectively configuring and matching the length, width, height, azimuth angle, and / or period of the plurality of rectangular columnar nanostructures on the lens body 110, thereby achieving the effect of simultaneously sensing and receiving red, green, and blue light signals without the need for separate illumination and sensing according to color. According to an embodiment of the present invention, in general, the ratio of the number of the plurality of first nanostructures 112R, the number of the plurality of second nanostructures 112G, and the number of the plurality of third nanostructures 112B in the plurality of nanostructures 122 can be substantially 1:1:1. Thus, the plurality of nanostructures 122 can be periodically arranged on the first surface 110' of the lens body 110 in a group consisting of one first nanostructure 112R, one second nanostructure 112G, and one third nanostructure 112B. In other words, the plurality of first nanostructures 112R, the plurality of second nanostructures 112G, and the plurality of third nanostructures 112B can be substantially evenly distributed on the first surface 110' of the lens body 110. According to an embodiment of the present invention, considering that the sensitivity of a photosensitive element to different wavelength bands may vary in practice and a compensation mechanism is required, the number of the plurality of first nanostructures 112R, the number of the plurality of second nanostructures 112G, and the number of the plurality of third nanostructures 112B in the plurality of nanostructures 122 may be different. For example, for a CMOS, blue light has the lowest photoelectric conversion efficiency, while green light has the highest photoelectric conversion efficiency. Therefore, the ratio of the number of the plurality of first nanostructures 112R, the number of the plurality of second nanostructures 112G, and the number of the plurality of third nanostructures 112B in the plurality of nanostructures 122 may be substantially 2:1:3. In this manner, the plurality of nanostructures 122 may be periodically disposed on the first surface 110' of the lens body 110 in a group consisting of two first nanostructures 112R, one second nanostructure 112G, and three third nanostructures 112B. This further enhances the reliability of the light-sensing signal of the present invention. Specifically, the plurality of first nanostructures 112R, the plurality of second nanostructures 112G, and the plurality of third nanostructures 112B can be substantially evenly distributed on the first surface 110' of the lens body 110. In other words, the various nanostructures can be periodically arranged as subsets on the first surface 110' of the lens body 110 based on their respective numbers. According to an embodiment of the present invention, taking color temperature requirements into consideration, for example, corresponding to a white balance color temperature of 6500 K, the ratio of the number of the plurality of first nanostructures 112R, the number of the plurality of second nanostructures 112G, and the number of the plurality of third nanostructures 112B in the plurality of nanostructures 122 may be substantially 1:1:1. Furthermore, corresponding to a white balance color temperature of 5000 K, the ratio of the number of the plurality of first nanostructures 112R, the number of the plurality of second nanostructures 112G, and the number of the plurality of third nanostructures 112B in the plurality of nanostructures 122 may be substantially 6:3:1. Similarly, regardless of the ratio of the number of the various nanostructures, the various nanostructures may be substantially evenly distributed on the first surface 110' of the lens body 110 to ensure accuracy of the light-sensing signals for each color. According to an embodiment of the present invention, to further improve the accuracy of light-sensing information, a color filter layer may be disposed on the photosensitive pixel P, interposed between the photosensitive pixel P and the first surface 110' of the lens body 110. The color filter layer may include a red filter, a green filter, and a blue filter, disposed on the first photosensitive sub-pixel SP1, the second photosensitive sub-pixel SP2, and the third photosensitive sub-pixel SP3, respectively. Specifically, a red filter may be disposed on the first photosensitive sub-pixel SP1, a green filter may be disposed on the second photosensitive sub-pixel SP2, and a blue filter may be disposed on the third photosensitive sub-pixel SP3. In other words, the red filter may be disposed between the first photosensitive sub-pixel SP1 and the first surface 110' of the lens body 110, the green filter may be disposed between the second photosensitive pixel SP1 and the first surface 110' of the lens body 110, and the blue filter may be disposed between the third photosensitive pixel SP1 and the first surface 110' of the lens body 110. In this way, it is ensured that each sub-pixel will not be disturbed by noise of non-corresponding colors of light, thereby preventing the accuracy of the light-sensing signal from being affected. Similarly, according to an embodiment of the present invention, when designing the phase difference matching of each nanostructure 122, consideration is also taken into account to prevent light of non-corresponding colors from being deflected toward their corresponding photosensitive sub-pixels. For example, the plurality of first nanostructures 112R will not deflect green light toward the second photosensitive sub-pixel SP2 and blue light toward the third photosensitive sub-pixel SP3. Similarly, the plurality of second nanostructures 112G will not deflect red light toward the first photosensitive sub-pixel SP1 and blue light toward the third photosensitive sub-pixel SP3. Furthermore, the plurality of third nanostructures 112B will not deflect red light toward the first photosensitive sub-pixel SP1 and green light toward the second photosensitive sub-pixel B. This ensures that each sub-pixel is not affected by noise from non-corresponding colors, which could affect the accuracy of the photosensitive signal. Preferably, according to an embodiment of the present invention, the plurality of first nanostructures 112R do not deflect green and blue light toward the first photosensitive sub-pixel SP1, the second photosensitive sub-pixel SP2, or the third photosensitive sub-pixel SP3; the plurality of second nanostructures 112G do not deflect red and blue light toward the first photosensitive sub-pixel SP1, the second photosensitive sub-pixel SP2, or the third photosensitive sub-pixel SP3; and the plurality of third nanostructures 112B do not deflect red and green light toward the first photosensitive sub-pixel SP1, the second photosensitive sub-pixel SP2, or the third photosensitive sub-pixel SP3. In other words, the plurality of first nanostructures 112R do not deflect green and blue light toward the photosensitive pixel P; the plurality of second nanostructures 112G do not deflect red and blue light toward the photosensitive pixel P; and the plurality of third nanostructures 112B do not deflect red and green light toward the photosensitive pixel P. According to an embodiment of the present invention, when the optical scanning module of the present invention is applied to a scanner, a plurality of optical scanning modules can be arranged in a row to form a scanning strip. For example, taking the short edge of an A4 (210 mm × 297 mms) paper as an example, to achieve an optical resolution of 150 dpi, 300 dpi, or 600 dpi, the scanning strip can include approximately 1240, 2480, or 4960 optical scanning modules. The scanner may also include a light source that provides white light for scanning objects (e.g., documents or papers to be scanned with colored patterns or text). The scanner's light source may include a plurality of sub-light emitting elements that respectively provide red light, green light, and blue light, and simultaneously provide the red light, green light, and blue light that constitute the white light for simultaneously scanning the object to be scanned. After the object to be scanned is illuminated by a light source, reflected light is incident on the second surface of the lens body 110. It is then transmitted through the lens body 110 to the first surface 110' of the lens body 110, and then transmitted through the first surface 110' of the lens body 110. The light is then deflected by the physical properties of the metasurface (the first surface 110' of the lens body 110) according to its wavelength band to the corresponding photosensitive sub-pixel, generating a light-sensitive signal. According to an embodiment of the present invention, the light source of the scanner can provide polarized light with a predetermined polarization direction or state, which can enhance the spectroscopic focusing effect of the nanostructure array 120 of the present invention. For example, the light source of the scanner can provide linearly polarized light or circularly polarized light, but is not limited thereto. The theoretical framework and optical formulas or inequalities presented above are merely simple examples, illustrating aspects of the present invention based on common geometric optics and the Jones matrix. Those skilled in the art may add, subtract, or modify the above formulas based on different conditions or needs. It should be noted that the key point of the present invention lies in the use of metamaterials that have the ability to control the transmission, refraction, polarization, phase, and other properties of penetrating light, forming a metasurface with metamaterial elements on a lens body to achieve the effect of spectroscopic focusing. The various physical characteristics of the nanostructures on the metasurface of the present invention, such as length, width, height, azimuth, and period, can vary or be altered individually or in any combination depending on their position, thereby achieving an appropriate or matching phase difference for transmitted light of different wavelengths. Traditional scanners capture images of different wavelengths by flashing light at high frequencies, using algorithms to correct for aberrations. Fast scanning speeds can result in incomplete image stitching. This invention offers the following advantages over traditional lenses: 1. The light source can use a constant white light source, eliminating the need for flickering and extending its lifespan. 2. Through the controlled configuration of metamaterial elements (nanostructures), images at multiple wavelengths can be captured simultaneously, eliminating the need to scan and record each wavelength separately, thereby increasing scanning speed. 3. Simultaneously capturing multiple wavelengths produces a more continuous image and reduces algorithm complexity. 4. By varying the arrangement of the material elements, the efficiency of different wavelengths can be adjusted, optimizing the absorption spectrum of the photosensitive element. The above description describes the implementation of the present invention through specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The above description is only a preferred embodiment of the present invention and is not intended to limit the scope of the present invention. Any equivalent changes or modifications that do not depart from the spirit disclosed by the present invention should be included in the following patent scope. 10: Lens 11: Lens body 11': Output surface 20: Output light 100: Lens 110: Lens body 110': First surface 120: Nanostructure array 122: Nanostructure 122B: Third nanostructure 122G: Second nanostructure 122R: First nanostructure P: Photosensitive pixel SP1: First photosensitive sub-pixel SP2: Second photosensitive sub-pixel SP3: Third photosensitive sub-pixel Figure 1 is a schematic diagram showing the lens structure in a conventional optical scanning module based on conventional technology; Figure 2 is a schematic diagram showing the structure of an optical scanning module according to an embodiment of the present invention; Figure 3 is a schematic diagram showing a nanostructure array according to an embodiment of the present invention; Figure 4 is a schematic diagram showing the configuration of a nanostructure array according to an embodiment of the present invention; Figure 5 is a schematic diagram showing the phase difference distribution according to an embodiment of the present invention; and Figure 6 is a schematic diagram showing the configuration of a three-dimensional nanostructure array according to an embodiment of the present invention. 110: Lens body 110': output surface 120:Nanostructure Array 122B: The third nanostructure 122G: Second nanostructure 122R: First Nanostructure

Claims

1. An optical scanning module, comprising: a lens body having a first surface and a second surface disposed opposite to each other, the first surface outputting light and the second surface receiving light; a nanostructure array including a plurality of nanostructures and disposed on the first surface; and a photosensitive pixel disposed facing the first surface, and including a first photosensitive sub-pixel, a second photosensitive sub-pixel, and a third photosensitive sub-pixel, wherein... The array of nanostructures deflects a portion of red light propagating in the lens body to the first photosensitive sub-pixel, a portion of green light propagating in the lens body to the second photosensitive sub-pixel, and a portion of blue light propagating in the lens body to the third photosensitive sub-pixel. The array of nanostructures includes: a plurality of first nanostructures configured to deflect red light to the first photosensitive sub-pixel; a plurality of second nanostructures configured to deflect green light to the second photosensitive sub-pixel; and a plurality of third nanostructures configured to deflect blue light to the third photosensitive sub-pixel. The plurality of first nanostructures, the plurality of second nanostructures, and the plurality of third nanostructures are substantially uniformly disposed on the first surface.

2. The optical scanning module as claimed in claim 1 further includes a light source that provides white light with circular or linear polarization to scan an object, wherein, The reflected light from the object travels through the lens body to the photosensitive pixel.

3. The optical scanning module as described in claim 2, wherein, Each of the plurality of nanostructures is a rectangular columnar nanostructure whose length and width are configured as a function of coordinates on the first surface.

4. The optical scanning module as described in claim 2, wherein, Each of the plurality of nanostructures is a rectangular columnar nanostructure whose length, width, and height are configured as a function of coordinates on the first surface.

5. The optical scanning module as described in any one of claims 2 to 4, wherein, Each of the plurality of nanostructures is a rectangular columnar nanostructure with an optical fast axis defining the azimuth angle of the rectangular columnar nanostructure, which is configured as a function of the coordinates on the first surface.

6. The optical scanning module as described in claim 1, wherein, The plurality of first nanostructures, the plurality of second nanostructures, and the plurality of third nanostructures are periodically disposed on the first surface in a subset manner according to their quantity ratio, wherein the period of the plurality of nanostructures is a constant.

7. The optical scanning module as claimed in claim 1, further comprising: a red filter disposed on the first photosensitive sub-pixel; a green filter disposed on the second photosensitive sub-pixel; and a blue filter disposed on the third photosensitive sub-pixel.

8. An optical scanning device comprising: a plurality of optical scanning modules as described in claim 1, configured in a row; and a light source providing white light for scanning an object.

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