Crosstalk reduction using multi-layer film angular offset

Abstract

A one-piece optical structure includes an optical film, a lens layer disposed on a first side of the optical film and having microlenses two-dimensionally arranged on the lens layer, and an optically opaque mask layer on a second side of the optical film defining a plurality of through-openings. The openings are in one-to-one correspondence with the microlenses, so that for collimated incident light, for at least one polarization state, and for at least one of a blue light wavelength range, a green light wavelength range, and a red light wavelength range, the optical film has an average transmittance T1 for an incident angle of less than 10 degrees, and has an average transmittance T2 for an incident angle of greater than 35 degrees, the mask layer has openings such that T1 / T2 > = 1.5, and regions of the mask layer between the openings have an average optical density greater than about 2 in a blue wavelength range, a green wavelength range, and a red wavelength range.

Description

SUMMARY OF THE INVENTION

[0001] In some aspects of the present specification, there is provided a one-piece optical structure including an optical film, a lens layer disposed on a first major side of the optical film, and an optically opaque mask layer disposed on a second major side of the optical film opposite the first major side. The optical film has a total of at least 10 polymer layers, wherein each polymer layer in the polymer layers has an average thickness of less than about 500 nm. The lens layer includes a plurality of microlenses two-dimensionally arranged on the lens layer. The optically opaque mask layer defines a plurality of substantially through openings therein. The openings correspond one-to-one with the microlenses of the lens layer, such that for substantially collimated incident light, for at least one polarization state, and for at least one of a blue light wavelength range extending from about 420 nm to about 480 nm, a green light wavelength range extending from about 490 nm to about 560 nm, and a red light wavelength range extending from about 590 nm to about 670 nm, the optical film has an average optical transmittance T1 for a first incident angle of less than about 10 degrees and an average optical transmittance T2 for a second incident angle of greater than about 35 degrees, such that the ratio T1 / T2 is greater than or equal to 1.5, and the region of the mask layer between the openings has an average optical density greater than about 2 in each of the blue light wavelength range, the green light wavelength range, and the red light wavelength range.

[0002] In some aspects of the present specification, there is provided a one-piece optical structure including a lens layer, an optically opaque mask layer, and an optical film disposed between the lens layer and the mask layer. The lens layer includes a plurality of microlenses. The optically opaque mask layer defines a plurality of spaced-apart substantially through openings therein such that the openings correspond one-to-one with the microlenses. The optical film includes a total of at least 10 polymer layers. Each polymer layer in these polymer layers has an average thickness of less than about 500 nm. For substantially collimated light incident on the optical structure, for at least one polarization state, for at least one wavelength in the visible light wavelength range extending from about 420 nm to about 680 nm, and for a one-piece comparative optical structure having the same structure as the one-piece optical structure except not including the optical film, the optical structure and the comparative optical structure have corresponding optical transmittances M1 and Mc1 for a first incident angle of less than about 10 degrees and corresponding optical transmittances M2 and Mc2 for a second incident angle of greater than about 25 degrees, such that the ratio M1 / Mc1 is greater than or equal to 0.5, the ratio Mc2 is greater than or equal to 2%, and the ratio M2 / Mc2 is less than or equal to about 0.7. BRIEF DESCRIPTION OF THE DRAWINGS

[0003] Figure 1A and Figure 1BShows a view of a display system including an integrated optical structure according to an embodiment of the present specification;

[0004] Figure 2 Is a side view of a multi-layer optical film structure according to an embodiment of the present specification;

[0005] Figure 3A And Figure 3B Provides information related to the optical characteristics of the integrated optical structure according to an embodiment of the present specification;

[0006] Figure 4 Is a side view of a comparative integrated optical structure without the multi-layer optical film of the present specification;

[0007] Figure 5A And Figure 5B Provides information related to the optical characteristics of the integrated optical structure compared to the comparative integrated optical structure according to an embodiment of the present specification and Figure 4 Of the additional information;

[0008] Figure 6A And Figure 6B Provides additional information related to the optical characteristics of the integrated optical structure according to an embodiment of the present specification; and

[0009] Figure 7A And Figure 7B Shows a view of the integrated optical structure according to an embodiment of the present specification. DETAILED DESCRIPTION

[0010] In the following description, reference is made to the accompanying drawings, which form a part of this disclosure and in which various embodiments are shown by way of illustration. The drawings are not necessarily to scale. It should be understood that other embodiments may be envisioned and made without departing from the scope or essence of this specification. Accordingly, the following detailed description should not be taken as limiting.

[0011] Today, many mobile devices rely on fingerprint sensing to provide security and identification features to the device. Typically, a sensor for detecting light reflected from an object near the screen (such as the surface of a finger) is placed behind the display screen. The optical film stack for the display screen can be designed to allow the light reflected from the finger to pass through the display screen and reach the underlying sensor. The optical film in the display screen can be designed to help direct the reflected light to the optical sensor and limit light contamination from other sources. For example, a small lens aperture film can be used as an angle filter to attempt to reduce light interference from the surrounding environment of the mobile device. However, optical crosstalk (where stray light from one small lens transmits through an adjacent aperture) limits the performance improvement of the optical system.

[0012] In some aspects of the present specification, an integrated optical structure uses a wavelength-selective multilayer optical film (MOF) in combination with a microlens aperture film to reduce optical crosstalk while maintaining good coaxial optical transmission. In some embodiments, the integrated optical structure includes an optical film, a lens layer disposed on a first major side of the optical film, and an optically opaque mask layer disposed on a second major side of the optical film opposite the first major side.

[0013] In some embodiments, the optical film includes a plurality of polymer layers having a total number of at least 10, or at least 20, or at least 50, or at least 100, or at least 150, or at least 200, or at least 250, or at least 300. In some embodiments, each of the polymer layers may have an average thickness of less than about 500 nm, or less than about 450 nm, or less than about 400 nm, or less than about 350 nm, or less than about 300 nm, or less than about 250 nm, or less than about 200 nm. In some embodiments, the lens layer may include a plurality of microlenses two-dimensionally arranged on the lens layer (e.g., on orthogonal x and y axes of the lens layer). In some such embodiments, the microlenses among the plurality of microlenses may include a plurality of metasurfaces having a plurality of nanostructures. In some such embodiments, the metasurface may be embedded in a material. As used in this specification, a metasurface includes a metasurface having a plurality (e.g., an array) of nanostructures. In such embodiments, the nanostructures may be configured to redirect or bend incident light by modifying the phase of the incident light.

[0014] In some embodiments, the optically opaque mask layer may define a plurality of substantially through openings therein. In some embodiments, each of the openings may extend from a first major surface of the mask layer facing the optical film to an opposite second major surface of the mask layer. In some embodiments, at least 60%, or at least 70%, or at least 80%, or at least 85%, or at least 90%, or at least 95% of the total volume of each of the openings may be filled with air. In other embodiments, at least 60%, or at least 70%, or at least 80%, or at least 85%, or at least 90%, or at least 95% of the total volume of each of the openings may be filled with a material other than air (e.g., an optically transparent adhesive).

[0015] In some embodiments, the integrated optical structure may further include an optical adhesive layer disposed on and in physical contact with the second major surface of the mask layer. In some such embodiments, where each of the openings extends from the first major surface to the second major surface of the mask layer, the optical adhesive layer may fill more than about 50%, or about 60%, or about 70%, or about 80%, or about 90%, or about 95% of the total volume of each of the openings.

[0016] In some embodiments, the openings may be arranged to correspond one-to-one with the microlenses such that, for substantially collimated incident light, for at least one polarization state (e.g., a first (x-axis) polarization state and a second (y-axis) polarization state that are mutually orthogonal), and for at least one of a blue light wavelength range extending from about 420 nm to about 480 nm, a green light wavelength range extending from about 490 nm to about 560 nm, and a red light wavelength range extending from about 590 nm to about 670 nm, the optical film may have an average optical transmittance T1 for a first incident angle of less than about 10 degrees, or less than about 8 degrees, or less than about 6 degrees, or less than about 4 degrees, or less than about 2 degrees, or less than about 1 degree, and may have an average optical transmittance T2 for a second incident angle of greater than about 35 degrees, or greater than about 40 degrees, or greater than about 45 degrees, or greater than about 50 degrees, or greater than about 55 degrees, or greater than about 60 degrees, such that the ratio of T1 / T2 is greater than or equal to 1.5, or greater than or equal to 2, or greater than or equal to 2.5, or greater than or equal to 5, or greater than or equal to 10, or greater than or equal to 25, or greater than or equal to 50, or greater than or equal to 100, or greater than or equal to 150, or greater than or equal to 200. In some embodiments, the regions of the mask layer between the openings may have an average optical density greater than about 2, or greater than about 2.5, or greater than about 3, or greater than about 3.5, or greater than about 4, or greater than about 4.5, or greater than about 5, or greater than about 5.5, or greater than about 6 in each of the blue light wavelength range, the green light wavelength range, and the red light wavelength range.

[0017] In some embodiments, for at least one polarization state and for at least one wavelength between at least one of the blue light wavelength range and the green light wavelength range and at least one of the green light wavelength range and the red light wavelength range, the optical film may have an optical transmittance T3 of less than about 15%, or less than about 10%, or less than about 8%, or less than about 6%, or less than about 5%, or less than about 4%, or less than about 3%, or less than about 2%.

[0018] In some embodiments, the display system may include a light source (e.g., a light-emitting diode) and any of the integrated optical structures described herein. In some embodiments, the integrated optical structure may be disposed between an optical sensor and a display panel (e.g., a liquid crystal display panel), the display panel being configured to generate an image for viewing by a user. In some such embodiments, the light source may be configured to emit light toward at least one finger (or stylus) placed by a user near the display panel. In some embodiments, the optical sensor may be configured to sense the presence of the finger by receiving at least a portion of the emitted light reflected by the finger. In some embodiments, the light source may be disposed inside the display panel. In some embodiments, the light source may be one or more pixels of the display panel. In some embodiments, the light source may be disposed on a side of the display system. In some embodiments, the light emitted from the light source may have a wavelength between about 800 nm and about 2000 nm, or between about 800 nm and about 1500 nm, or between about 800 nm and about 1200 nm. In some embodiments, the emitted light may have a visible light wavelength between about 400 nm and about 800 nm.

[0019] According to some aspects of the present specification, the integrated optical structure includes a lens layer, an optically opaque mask layer, and an optical film disposed between the lens layer and the mask layer. In some embodiments, the lens layer may include a plurality of microlenses. In some embodiments, the optically opaque mask layer may define a plurality of spaced-apart substantially through openings therein, the openings corresponding one-to-one with the microlenses. In some embodiments, each of the openings may extend from a first major surface of the mask layer facing the optical film to an opposite second major surface of the mask layer. In some embodiments, at least 60%, or at least 70%, or at least 80%, or at least 85%, or at least 90%, or at least 95% of the total volume of each of the openings may be filled with air. In other embodiments, at least 60%, or at least 70%, or at least 80%, or at least 85%, or at least 90%, or at least 95% of the total volume of each of the openings may be filled with a material other than air (e.g., an optically transparent adhesive).

[0020] In some embodiments, the optical film may include a plurality of polymer layers having a total number of at least 10, or at least 20, or at least 50, or at least 100, or at least 150, or at least 200, or at least 250, or at least 300. In some embodiments, each of the polymer layers may have an average thickness of less than about 500 nm, or less than about 450 nm, or less than about 400 nm, or less than about 350 nm, or less than about 300 nm, or less than about 250 nm, or less than about 200 nm.

[0021] In some embodiments, for substantially collimated light incident on the optical structure, for at least one polarization state (e.g., the x-axis or y-axis of the optical structure), for at least one wavelength in the visible light wavelength range extending from about 420 nm to about 680 nm, and for an integral comparison optical structure having the same structure as the integral optical structure except that it does not include the optical film (i.e., the space occupied by the optical film in the embodiments of this specification is replaced by a layer having a thickness similar to that of the optical film and a selected uniform refractive index such that the pinhole array (i.e., the openings in the opaque mask layer) is located at the focal point of the lens array), the optical structure and the comparison optical structure may have respective optical transmittances M1 and Mc1 for a first incident angle of less than about 10 degrees, or less than about 8 degrees, or less than about 6 degrees, or less than about 4 degrees, or less than about 2 degrees, or less than about 1 degree, and may have respective optical transmittances M2 and Mc2 for a second incident angle of greater than about 25 degrees, or greater than about 30 degrees, or greater than about 35 degrees, or greater than about 40 degrees, or greater than about 45 degrees, or greater than 50 degrees, or greater than about 55 degrees, or greater than about 60 degrees. The ratio of M1 / Mc1 may be greater than or equal to 0.5, Mc2 may be greater than about 2%, or greater than about 3%, or greater than about 4%, or greater than about 5%, or greater than about 6%, or greater than about 7%, or greater than about 8%, or greater than about 9%, or greater than about 10%, and the ratio of M2 / Mc2 may be less than or equal to 0.7, or less than or equal to 0.6, or less than or equal to 0.5, or less than or equal to 0.4, or less than or equal to 0.3, or less than or equal to 0.2, or less than or equal to 0.1, or less than or equal to 0.05.

[0022] In some embodiments, when the mask layer further includes a first major surface facing the optical film and an opposite second major surface, the integral optical structure may further include an optical adhesive layer disposed on and in physical contact with the second major surface of the mask layer. In some such embodiments, the optical adhesive layer may fill more than about 50%, or more than about 60%, or more than about 70%, or more than about 80%, or more than about 90%, or more than about 95% of the total volume of each of the openings.

[0023] Turning now to the drawings, Figure 1A and Figure 1BA view of a display system including an embodiment of an integrated optical structure according to this specification is provided. In some embodiments, the display system 300 includes a display panel 80, one or more light sources 100, 101, an integrated optical structure 200, and an optical sensor 110. In some embodiments, the display panel 80 is configured to generate an image 81 for a user 90 to view. In some embodiments, the light sources 100, 101 may emit light 100a towards an object 91 (e.g., a finger of the user 90) such that the light 100a is reflected from the object 91 and at least a portion of the light 100a is reflected as reflected light 100b. In some embodiments, the reflected light 100b passes through the optical structure 200 and is received by the optical sensor 110 such that the optical sensor 110 can at least sense the presence of the object 91.

[0024] In some embodiments, the light source 100 may be disposed on a side 301 of the display system 300. In some embodiments, the light source 101 may be disposed inside the display panel 80. In some embodiments, the emitted light 100a may include visible light wavelengths between about 400 nm and about 800 nm. In some embodiments, the emitted light 100a may include wavelengths between about 800 nm and about 2000 nm or between about 800 nm and about 1500 nm or between about 800 nm and about 1200 nm.

[0025] In some embodiments, the integrated optical structure 200 may include an optical film 10, a lens layer 20, and an optically opaque mask layer 30. In some embodiments, the optical film may include a plurality of polymer layers (e.g., see Figure 2 ). In some embodiments, the lens layer 20 may be disposed on a first major side 13 of the optical film 10 and may include a plurality of microlenses 21 two-dimensionally arranged on the lens layer 20 (e.g., arranged in a plane defined by an x-axis and a y-axis defined as Figure 1A ). See also Figure 1B , which shows a top plan view of the lens layer 20 having a plurality of microlenses 21.

[0026] In some embodiments, the optically opaque mask layer 30 may be disposed on a second major side 14 of the optical film 10, the second major side 14 being opposite to the first major side 13 of the optical film 10. In some embodiments, the optically opaque mask layer (or more simply referred to as the "mask layer") 30 may define a plurality of substantially through openings 31 therein. In some embodiments, the through openings 31 extend from a first major surface 33 of the mask layer 30 to an opposite second major surface 34 of the mask layer 30. In some embodiments, the openings 31 may correspond one-to-one with the microlenses 21 (i.e., be substantially aligned with the microlenses 21, as shown by the vertical dashed lines in Figure 1A ).

[0027] Figure 1A The object 91 is shown as a line representing the outline 91a of the object 91. For example, the object 91 may be a finger of the user 90, and the outline 91a may be the pattern of a fingerprint. The light 100a emitted by the light sources 100, 101 may be reflected as reflected light 100b and / or 100c. A part of the reflected light (100b) may cause the light to be transmitted through the optical film 10 and reflected at an angle through the opening 31 in the opaque mask layer 30, while another part of the reflected light (100c) may cause the light to be substantially blocked or reflected by the optical film 10 (see, for example, the reflected light 100d reflected from the inside of the optical film 10) and reflected at an angle such that it cannot pass through the opaque mask layer 30 along the path 100e, resulting in crosstalk contamination.

[0028] In some embodiments, the one-piece optical structure 300 may further include an optical adhesive layer 70 disposed on and in physical contact with the second major surface 34 of the mask layer 30. In some such embodiments, when each of the openings 31 extends from the first major surface 33 to the second major surface 34 of the mask layer 30, the optical adhesive layer 70 may fill more than about 50%, or more than about 60%, or more than about 70%, or more than about 80%, or more than about 90%, or more than about 95% of the total volume of each of the openings 31. In some embodiments, the mask layer 30 further includes a region 32 between the openings 31. In some embodiments, the region 32 may have an average optical density greater than about 2, or greater than about 2.5, or greater than about 3, or greater than about 3.5, or greater than about 4, or greater than about 4.5, or greater than about 5, or greater than about 5.5, or greater than about 6 in each of the blue light wavelength range, the green light wavelength range, and the red light wavelength range (e.g., see the blue light 60 wavelength range, the green light 61 wavelength range, and the red light 62 wavelength range defined as Figure 3A In some embodiments, at least 60%, or at least 70%, or at least 80%, or at least 85%, or at least 90%, or at least 95% of the total volume of each of the openings 31 is filled with air. In some embodiments, at least 60%, or at least 70%, or at least 80%, or at least 85%, or at least 90%, or at least 95% of the total volume of each of the openings 31 is filled with a material 71 other than air.

[0029] Figure 2 is shown such as Figure 1ASide view of the optical film laminate structure of an embodiment of the optical film 10. In some embodiments, the optical film 10 may include a total of at least 10, or 20, or 30, or 40, or 50, or 100, or 150, or 200, or 250, or 300 polymer layers (e.g., micro-layers) 11, 12. In some embodiments, each of the polymer layers 11, 12 may have an average thickness of less than about 500 nm, or 450 nm, or 400 nm, or 350 nm, or 300 nm, or 250 nm, or 200 nm. In some embodiments, the refractive index of the polymer layers 11, 12 and / or the total number of the polymer layers 11, 12 and / or the thickness profile exhibited by the plurality of polymer layers 11, 12 as a whole may be configured such that a desired optical transmission / reflection profile can be created for the optical film 11. In some embodiments, the optical film 10 may have additional layers (e.g., Figure 2 outer "surface" layers such as those shown but not numbered in the figure above and below the plurality of polymer layers 11, 12).

[0030] In some embodiments, for each of a first angle of incidence θ1 and a second angle of incidence θ2, the substantially collimated incident light 50, 51 may exhibit different average optical transmittances. That is, the amount of optical transmittance may vary according to the change in the angle of incidence. In some embodiments, the presence of the lens layer 20 changes the angle of incidence of the light reaching the opaque mask layer 30, enabling improved angular filtering of the light passing through the stack.

[0031] Other details regarding the optical properties of the optical film 10 in at least one embodiment are provided elsewhere herein. For example, Figure 3A and 3B provide information related to the optical properties of an integrated optical structure such as an embodiment of the integrated optical structure 200 in Figure 1A .

[0032] In some embodiments, for the substantially collimated incident light 50, 51 (as Figure 2 shown), and for at least one polarization state (e.g., polarized to the x-axis or y-axis as defined in Figure 1A ), and for at least one of a blue light wavelength range 60 extending from about 420 nm to about 480 nm, a green light wavelength range 61 extending from about 490 nm to about 560 nm, and a red light wavelength range 62 extending from about 590 nm to about 670 nm, the optical film 10 (e.g., Figure 1A or Figure 2 the optical film 10) for a first angle of incidence of less than about 10 degrees, or less than about 8 degrees, or less than about 6 degrees, or less than about 4 degrees, or less than about 2 degrees, or less than about 1 degree (e.g., Figure 2The θ1) may have an average optical transmittance T1, and for a second incident angle greater than about 35 degrees, or greater than about 40 degrees, or greater than about 45 degrees, or greater than about 50 degrees, or greater than about 55 degrees, or greater than about 60 degrees (e.g., Figure 2 the θ2) may have an average optical transmittance T2. In some embodiments, the ratio of T1 / T2 may be greater than or equal to about 1.5, or greater than or equal to about 2, or greater than or equal to about 2.5, or greater than or equal to about 5, or greater than or equal to about 10, or greater than or equal to about 25, or greater than or equal to about 50 or 100, or greater than or equal to about 150, or greater than or equal to about 200.

[0033] For example, Figure 3A Graphs showing the plots of three different optical film examples OF1, OF2, and OF3 are shown. Each film OF1, OF2, OF3 corresponds to Figure 3A two different plots in OF1(0) shows the optical transmittance curve of film OF1 for incident light 50 with a given incident angle θ1 of 0 degrees (e.g., substantially perpendicular to the surface of the optical film), and OF1(60) shows the optical transmittance curve of the same film (OF1) for incident light 51 with a given incident angle θ2 of 60 degrees. Similar plots are provided for OF2(0), OF2(60), OF3(0), and OF3(60).

[0034] Figure 3B A table is provided that summarizes the average optical transmittance values representing the data in the Figure 3A graph. Figure 3B Each row in represents one of a blue light wavelength range 60, a green light wavelength range 61, and a red light wavelength range 62. Figure 3B Each column in shows the average optical transmittance seen for each film and each incident angle for the three wavelength ranges. For example, by looking at the green light wavelength range 61 in the table, we see that OF1 has a transmittance value of 0.92 (92%) at an incident angle of 0 degrees (labeled T1), and OF1 has an optical transmittance value of 0.39 (39%) at an incident angle of 60 degrees (labeled T2). The ratios of T1 / T2 for each of the films OF1, OF2, OF3 in the green light wavelength range 61 are 2.36, 3.22, and 2.72, as shown in the Figure 3B table in

[0035] Returning to Figure 3A , for at least one polarization state and for at least one wavelength 63 between at least one of the blue light wavelength range and the green light wavelength range and at least one of the green light wavelength range and the red light wavelength range (e.g., as in Figure 3AAs shown (at 555 nm), the optical film may have an optical transmittance T3 of less than about 15%, or less than about 10%, or less than about 8%, or less than about 6%, or less than about 5%, or less than about 4%, or less than about 3%, or less than about 2% (T3 is shown in Figure 3A as being about 0.02 or 2%).

[0036] Figure 4 is a side view of a comparative one-piece optical structure 210 of a multi-layer optical film without this specification. Figure 4 The comparative one-piece optical structure 210 of Figure 1A has the same structure as the one-piece optical structure 200 of , but the comparative one-piece optical structure 210 does not include the optical film 10. (Instead, the optical film 10 is replaced by a layer 15 having a similar thickness and a selected uniform refractive index such that the "pinhole array" of the opaque mask layer 30 is located at the focal point of the microlens array of the lens layer 20.)

[0037] Except for not having the optical film 10 (and its layer 15 replacement), the comparative one-piece optical structure 210 includes other components of the one-piece optical structure 200, and it is assumed that components with similar numbers between the structure 200 and the structure 210 have the same functions, so they will not be elaborated here. Figure 4 is provided for discussion purposes, and the optical performance of the one-piece optical structure 200 will be compared with Figure 5A and Figure 5B and Figure 6A and Figure 6B the optical performance of the comparative one-piece optical structure 210 in

[0038] In Figure 4 the comparative one-piece optical structure 210 of Figure 1A , the reflected light 100c from Figure 1A is shown (shown at an angle similar to Figure 1A ). Since there is no optical film 10 in this embodiment, the reflected light 100c transmits through the replacement layer 15 and through one or more openings 31 in the opaque mask layer 30, thereby generating "crosstalk" contamination at the optical sensor 110 (instead of being reflected or blocked by the optical film 10 as shown in Figure 1A ).

[0039] First, turning to Figure 5A and Figure 5B , the optical structure 200 and the comparative optical structure 210 may have corresponding optical transmittances M1 and Mc1 for a first incident angle α1 of less than about 10 degrees, or less than about 8 degrees, or less than about 6 degrees, or less than about 4 degrees, or less than about 2 degrees, or less than about 1 degree (e.g., α1 of 0 degrees). For example, the values of M1 and Mc1 are shown in Figure 5A , and this figure isFigure 5A A close-up view of the graph shown, showing the optical transmittance values M1 and Mc1 at α1 (0 degrees). Similarly, Figure 6A is Figure 5A a close-up view of the graph of, but showing the optical transmittance values M2 and Mc2 at α2 (40 degrees).

[0040] As Figure 5B and Figure 6A shown, the ratio of M1 / Mc1 can be greater than or equal to about 0.5, and the ratio of M2 / Mc2 can be less than or equal to about 0.7, or less than or equal to about 0.6, or less than or equal to about 0.5, or less than or equal to about 0.4, or less than or equal to about 0.3, or less than or equal to about 0.2, or less than or equal to about 0.1, or less than or equal to about 0.05. For example, when the α2 value is 40 degrees, Mc2 (the transmittance of the comparative optical structure 210 without the optical film 10) is about 10.5%, and M2 (the transmittance of the optical structure 200 with the optical film 20) is about 0.01%. In other words, the presence of the optical film 10 in the integrated optical structure 200 significantly reduces the amount of optical transmittance at a relatively high incident angle (e.g., 40 degrees). Figure 6B Shows a graph of M2 / Mc2 (the ratio of the transmittance of the optical films OF1, OF2, and OF3 with the optical film 10 to the transmittance of a similar film without the optical film 10) at an incident angle of 40 degrees.

[0041] Figure 7A and Figure 7B Provide a view of an alternative embodiment 200a of the integrated optical structure 200a. Figure 7A and Figure 7B The alternative embodiment shown is similar to Figure 1A the embodiment of the integrated optical structure 200, and it should be assumed that all similarly numbered components have the same function. In the alternative embodiment 200a, the microlens includes a plurality of superlenses 21a having a plurality of nanostructures 22. For the purposes of this specification, the superlens 21a includes a metasurface 24, which includes a plurality of nanostructures 22 such as a regular array. In some embodiments, the nanostructures 22 can be configured to redirect or bend the incident light 25 by modifying the phase of the incident light 25.

[0042] In some embodiments, the nanostructures 22 can be made of a high refractive index material, which can include semiconductors, metal oxides, or metal nitrides. The high refractive index material can include at least one of silicon, germanium, titanium, zirconium, tantalum, hafnium, niobium, zinc, or cerium; oxides of titanium, zirconium, tantalum, hafnium, niobium, zinc, or cerium; nitrides of titanium, zirconium, tantalum, hafnium, niobium, zinc, or cerium; sulfides of titanium, zirconium, tantalum, hafnium, niobium, zinc, or cerium; or combinations thereof.

[0043] In some embodiments, the nanostructure 22 may be embedded in a matrix material 23 having a refractive index lower than that of the nanostructure. The matrix material 23 may be formed from a thermoplastic material. The matrix material 23 may be formed from poly(methyl methacrylate), polycarbonate, polypropylene, polyethylene, polystyrene, polyester, or polyamide. The matrix material 23 may be formed from a polymerizable composition including an acrylate or methacrylate component. The matrix material 23 may include a fluoropolymer, a (meth)acrylate (co)polymer, or a silica-containing polymer.

[0044] Terms such as "about" will be understood in the context in which they are used and described by a person of ordinary skill in the art in this specification. If it is not clear to a person of ordinary skill in the art in the context in which they are used and described in this specification how "about" is applied to a quantity expressing the size, amount, and physical properties of a feature, then "about" will be understood to mean within 10% of the specified value. A quantity given as about a specified value may be precisely the specified value. For example, if it is not clear to a person of ordinary skill in the art in the context in which they are used and described in this specification, a quantity having a value of about 1 means that the quantity has a value between 0.9 and 1.1, and the value may be 1.

[0045] A person of ordinary skill in the art will understand terms such as "substantially" in the context in which they are used and described in this specification. If it is not clear to a person of ordinary skill in the art in the context in which they are used and described in this specification how "substantially equal" is used, then "substantially equal" will refer to approximately the same as the case of "about" as described above. If it is not clear to a person of ordinary skill in the art in the context in which they are used and described in this specification how "substantially parallel" is used, then "substantially parallel" will refer to within 30 degrees of being parallel. In some embodiments, directions or surfaces described as being substantially parallel to each other may be within 20 degrees or 10 degrees of being parallel, or may be parallel or nominally parallel. If it is not clear to a person of ordinary skill in the art in the context in which they are used and described in this specification how "substantially aligned" is used, then "substantially aligned" will refer to being aligned within 20% of the width of the object being aligned. In some embodiments, objects described as being substantially aligned may be aligned within 10% or 5% of the width of the object being aligned.

[0046] All of the above-referenced references, patents, and patent applications are hereby incorporated by reference in their entirety in a consistent manner. In the event of any inconsistency or conflict between the incorporated reference section and this application, the information in the foregoing description shall prevail.

[0047] Unless otherwise indicated, descriptions of elements in the figures are to be understood as applying equally to corresponding elements in other figures. Although specific embodiments have been illustrated and described herein, those of ordinary skill in the art will recognize that, without departing from the scope of the present disclosure, various alternative and / or equivalent specific implementations may be used in place of the specific embodiments shown and described herein. This application is intended to cover any modifications or variations of the specific embodiments discussed herein. Accordingly, the present disclosure is intended to be limited only by the claims and their equivalents.

Claims

1. An integrated optical structure, the integrated optical structure comprises: an optical film including a plurality of polymer layers with a total number of at least 10, each of the polymer layers having an average thickness of less than about 500 nm; a lens layer disposed on a first major side of the optical film and including a plurality of microlenses two-dimensionally arranged on the lens layer; and an optically opaque mask layer disposed on a second major side of the optical film opposite to the first major side and having a plurality of substantially through openings defined therein, the openings corresponding to the microlenses one by one, such that for substantially collimated incident light, for at least one polarization state, and for at least one of a blue light wavelength range extending from about 420 nm to about 480 nm, a green light wavelength range extending from about 490 nm to about 560 nm, and a red light wavelength range extending from about 590 nm to about 670 nm: the optical film has an average optical transmittance T1 for a first incident angle of less than about 10 degrees and an average optical transmittance T2 for a second incident angle of greater than about 35 degrees, T1 / T2≥1.5; and the region of the mask layer between the openings has an average optical density greater than about 2 in each of the blue light wavelength range, the green light wavelength range, and the red light wavelength range.

2. The integrated optical structure according to claim 1, wherein each of the openings extends from a first main surface of the mask layer facing the optical film to a second main surface opposite thereto.

3. The integrated optical structure according to claim 2, wherein at least 60% of the total volume of each of the openings is filled with air.

4. The integrated optical structure according to claim 2, wherein at least 60% of the total volume of each of the openings is filled with a material other than air.

5. The integrated optical structure according to claim 1, wherein the mask layer further includes a first main surface facing the optical film and a second main surface opposite thereto, and the integrated optical structure further includes an optical adhesive layer disposed on and in physical contact with the second main surface of the mask layer.

6. The integrated optical structure according to claim 5, wherein each of the openings extends from the first main surface of the mask layer facing the optical film to the second main surface (34) of the mask layer, and wherein the optical adhesive layer fills more than about 50% of the total volume of each of the openings.

7. The integrated optical structure according to claim 5, wherein for the at least one polarization state and for at least one wavelength between at least one of the blue light wavelength range and the green light wavelength range and at least one of the green light wavelength range and the red light wavelength range, the optical film has an optical transmittance of less than about 15%.

8. A display system, the display system including a light source and the integrated optical structure according to claim 1 disposed between an optical sensor and a display panel, the display panel being configured to generate an image for a user to view, the light source being configured to emit light toward at least one finger placed by the user near the display panel, and the optical sensor being configured to sense the presence of the finger by receiving at least a portion of the emitted light reflected by the finger.

9. The display system according to claim 8, wherein the light source is disposed inside the display panel.

10. The display system according to claim 8, wherein the light source is disposed on a side of the display system.

11. The display system according to claim 8, wherein the emitted light has a wavelength between about 800 nm and about 2000 nm.

12. The display system according to claim 8, wherein the emitted light has a visible light wavelength between about 400 nm and about 800 nm.

13. The integrated optical structure according to claim 1, wherein the at least one polarization state includes each of a first polarization state and a second polarization state that are orthogonal to each other.

14. The integrated optical structure according to claim 1, wherein the microlenses among the plurality of microlenses include a plurality of superlenses having a plurality of nanostructures.

15. The integrated optical structure according to claim 1, wherein the superlenses are embedded in a material.

16. An integrated optical structure, the integrated optical structure comprising: a lens layer including a plurality of microlenses; an optically opaque mask layer having a plurality of spaced-apart substantially through openings defined therein, the openings corresponding to the microlenses one by one; and an optical film disposed between the lens layer and the mask layer and including a plurality of polymer layers with a total number of at least 10, each polymer layer having an average thickness of less than about 500 nm, such that for substantially collimated light incident on the optical structure, for at least one polarization state, and for at least one wavelength in the visible light wavelength range extending from about 420 nm to about 680 nm, and for an integrated comparative optical structure having the same structure as the integrated optical structure except not including the optical film: the optical structure and the comparative optical structure have respective optical transmittances M1 and Mc1 for a first incident angle of less than about 10 degrees, and respective optical transmittances M2 and Mc2 for a second incident angle of greater than about 25 degrees, M1 / Mc1≥0.5, Mc2≥2%, and M2 / Mc2≤0.

7.

17. The integrated optical structure according to claim 16, wherein each of the openings extends from a first major surface of the mask layer facing the optical film to an opposite second major surface of the mask layer.

18. The integrated optical structure according to claim 17, wherein at least 60% of the total volume of each of the openings is filled with air.

19. The integrated optical structure according to claim 17, wherein at least 60% of the total volume of each of the openings is filled with a material other than air.

20. The integrated optical structure according to claim 16, wherein the mask layer further includes a first major surface facing the optical film and an opposite second major surface, and the integrated optical structure further includes an optical adhesive layer disposed on and in physical contact with the second major surface of the mask layer.

21. The integrated optical structure according to claim 20, wherein each of the openings extends from the first major surface (33) of the mask layer facing the optical film to the second major surface of the mask layer, and wherein the optical adhesive layer fills more than about 50% of the total volume of each of the openings.

22. The integrated optical structure according to claim 16, wherein the at least one polarization state includes each of a first polarization state and a second polarization state that are orthogonal to each other.

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