Collimated arrays for optical sensing devices

Abstract

An optical sensor system includes an optical sensor array and a plurality of optical filters arranged on an integrated circuit, wherein a bottom surface of the plurality of optical filters is located above a top surface of the optical sensor array. The optical sensor system further includes an incident angle layer, the incident angle layer including a top surface, a bottom surface, and a thickness Y, wherein the bottom surface of the incident angle layer is located at a predetermined distance X from the top surface of the plurality of optical filters, and the incident angle layer includes a plurality of collimating elements, each collimating element of the incident angle layer having an aperture width Z.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This U.S. utility patent application also claims the benefit of U.S. Provisional Application No. 62 / 932,304, filed on July 11, 2019, entitled “Collimating Arrays for Optical Sensing Devices,” pursuant to 35 U.S.C. 119(e), the entire contents of which are incorporated herein by reference and made a part of this U.S. utility patent application for any and all purposes. Technical Field

[0003] The present invention relates generally to spectroscopy and, more particularly, to spectral sensors using interference-based filters. Background Art

[0004] Spectroscopy devices have proven useful in applications across a variety of industries, including, for example, health, bioassays, agriculture, chemistry, and fitness. Interference-based filters, such as Fabry-Perot filters, have been shown to provide useful spectral information when used in conjunction with spectroscopy. Light incident on the sensor surface at relatively small angles passing through interference-based filters can negatively impact the performance of the sensor. Many approaches have been proposed to manage the angle of incidence through interference-based filters, including the addition of objective lenses, slits, and collimators, either alone or in combination. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] Figure 1 The filter transmittance or response from 740 nm to 790 nm according to different f-numbers of the present invention is shown;

[0006] Figure 2 shows a top-down illustration of an optical sensor covered with an optical filter according to the present invention;

[0007] Figure 3 A side view of an exemplary optical sensor is provided, showing incident light striking a surface of a portion of an optical sensor according to the present invention;

[0008] Figure 4A showing a perspective view of a portion of an exemplary optical sensor according to the present invention;

[0009] Figure 4B shows a side view of an exemplary optical sensor according to the present invention;

[0010] Figure 5 shows a side view of another exemplary optical sensor according to the present invention;

[0011] Figure 6 shows a side view of another exemplary optical sensor according to the present invention;

[0012] Figure 7 shows a side view of another exemplary optical sensor according to the present invention;

[0013] Figure 8 shows a side view of another exemplary optical sensor according to the present invention;

[0014] Fig.9A shows a side view of another exemplary optical sensor according to the present invention;

[0015] Fig. 9B shows another side view of another exemplary optical sensor according to the present invention;

[0016] Fig. 10A A top view of an exemplary angle of incidence device having an array of pinhole elements overlying an optical sensor array according to the present invention is provided;

[0017] Fig. 10B shows light projected from an incident angle according to the present invention;

[0018] Fig.11A shows examples of desired and undesired angles of incidence of passing light through a pinhole element of an angle of incidence device according to the present invention;

[0019] Fig. 11B An example of an angle of incidence device having an absorbing surface coating and an absorbing sidewall coating according to the present invention is provided;

[0020] Figures 12A to 12F Examples of pinhole element shapes / structures suitable for reducing the incidence of unintended reflected light according to the present invention are provided;

[0021] Fig.13 A side view of an exemplary optical sensor according to the present invention having an angle limiting element located above an incident angle device is provided;

[0022] Fig.14 A side view of another exemplary optical sensor according to the present invention is provided, the optical sensor having an angle limiting element located above an incident angle device;

[0023] Fig.15 A side view of another exemplary optical sensor according to the present invention having an angle of incidence device formed as an angle of incidence stack is provided;

[0024] Fig.16 A top view of an exemplary optical sensor according to the present invention having an incident angle stack is provided;

[0025] Figures 17A to 17DA side view of an exemplary optical sensor having various elements integrated with an incident angle device to form an incident angle stack according to the present invention is provided; and

[0026] Fig.18 A method of manufacturing an optical sensor system according to the present invention is provided. DETAILED DESCRIPTION

[0027] Interference-based filters, such as Fabry-Perot filters, typically have a strong angular dependence. For example, when light passes through a Fabry-Perot filter at angles greater than plus or minus 10°, the filter response can change (e.g., a broader filter response may occur due to a shift to a lower spectral range). Figure 1 Shown is the filter transmittance or filter response from 740 nanometers to 790 nanometers for different f-numbers (the f-number is the ratio of the focal length of the system to the entrance aperture diameter) based on different incident light angles.

[0028] A collimated light beam has rays that are substantially parallel and therefore travel with minimal spread. For example, a perfectly collimated light beam with no divergence would not spread out with distance; diffraction effectively prevents the creation of any such beam. Light can be approximated to be collimated by a number of processes, such as through a collimator. Perfectly collimated light is sometimes said to be focused at infinity. Thus, as the distance from a point source increases, the spherical wavefront becomes flatter and more closely resembles a perfectly collimated plane wave. In Figure 1 In the 3D image, line A represents a substantially collimated filter response (a "normal collimated" response), while lines B and C show filter responses with the same chief ray angle (CRA) but different beam f-numbers (i.e., more angles of incidence). (The CRA is the ray passing through the center of the aperture of the optical system from an off-axis object point.) In many applications, this angular dependence is problematic and must be mitigated.

[0029] Figure 2 A top-down illustration of an optical sensor 100 is shown, which is covered with filters 110, 120, and 130 that are each optimized for one of three spectral bands. As shown, filters 110, 120, and 130 are crossed on the surface of optical sensor 100 as an array. Alternatively, filters 110, 120, and 130 can use different patterns or even repeat in a random pattern to pass the filter response to the sensor below the filter array. In one example (not shown), more than 3 spectral bands can be used to cover the sensor as desired in almost any practical configuration. In one embodiment, optical sensor 100 is an example of an optical sensor for diffuse spectroscopy, where a spectral filter array is associated with the optical sensor to provide diffuse spectral sensing.

[0030] Diffuse spectroscopy can be particularly sensitive to the uniformity and stability of the angle of incidence of the light illuminating the sensor, so the angle of incidence of the light illuminating the sensor array is preferably unmodulated in a relative sense as the angle of incidence of the light illuminating the surface of the spectral filter changes. In one example, when each spectral band of the filter array (such as filter 110, filter 120, and filter 130 (together forming a set of spectral bands or spectra)) is spatially distributed across the surface of the sensor array, the spatial distribution can have a significant impact on the performance of the diffuse optical spectrometer. This is due, at least in part, to the fact that when a particular filter passes light of varying intensities, the reconstructed spectrum illuminating the sensor array will be distorted or "colored." The colored spectrum can be compensated (calibrated) electronically, however, if the uniformity of the light passing through the filter changes over time, or if the CRA or angle of the incident light changes, the reconstructed spectrum will be unstable. In such examples, the reconstructed spectrum will appear to have a change in spectral response as the angle of incidence of the incident light illuminating the optical sensor changes.

[0031] Diffuse optical sensors can benefit from reducing the effect of variations in the angle of incidence of the light illuminating the sensor array on the sensor, and from ensuring that the uniformity of the light passing through the sensor is substantially independent of the angle of incidence of the light illuminating the sensor array. Therefore, in order to provide a stable filter response for the optical sensor, it is preferred to limit the angle of incidence at which the incident light strikes the surface of the optical sensor. One way to provide a stable filter response is to ensure that all optical sensors, and therefore all filters, experience substantially the same variation in angular response, so that the effect on all sensors is uniform. This ensures that the spectrum of diffuse spectroscopy does not experience a large amount of "re-coloring".

[0032] In one embodiment, a lens or lens system may be used to collimate light that illuminates a sensor and / or filter array. Lens systems typically require a relatively large form factor, especially given the large f-numbers (e.g., f / 2 or higher) associated with spectral filters. Lens systems may also be relatively thick and require expensive optical stacks. The lens and / or lens system may also be sensitive to variations in the angle of incidence and CRA of incident light incident upon the optical sensor through the lens, resulting in non-uniform variations in angles through the sensor array. These non-uniform variations in angles may have different effects on different sensors and their spectral responses. Additionally, since the lens or lens system will have to focus the incident light onto different parts of the "scene," the properties of different parts of the scene will be projected onto different parts of the sensor array, resulting in a non-diffuse spectral response.

[0033] In another exemplary embodiment, a pinhole device may be used on the surface of the sensor. Figure 3A side view of an exemplary optical sensor is provided, for example, showing incident light 180 passing through such a pinhole device from Figure 2 The surface of a portion of the optical sensor 100 is illuminated. In an example, an incident angle device 140 (a device capable of narrowing or guiding incident light when the incident light passes through the incident angle device) of a predefined thickness H passes the regulated light 150 through an aperture of a predetermined width W of the incident angle device 140. In an example, the aperture is an opening, an open space, or a filled open space, which may have a shape including but not limited to a circle, a triangle, a square, a star, a hexagon, an octagon, or even an irregular shape.

[0034] In one example, incident light 180 strikes a surface of the incident angle device 140, which intercepts light striking the surface beyond a certain angle determined by a predefined width W and a predefined thickness H of the incident angle device 140. The incident angle device 140 effectively "conditions" the incident light 180 to produce a conditioned light 150 that strikes the surface of the filter array 160. The predefined distance D is the distance between the lower surface of the incident angle device 140 and effectively defines an area exposed to the conditioned light 150 and an area outside of the area exposed to the conditioned light 150. Figure 3 As discussed in , the filter array 160 covers the sensor, Figure 3 Shown in FIG. 1 is sensor array 170 .

[0035] Figure 3 The final sensor example shown in does limit the target angle through the surface of the filter array, however, if the sensor comprises a large area, the CRA through the surface of the sensor device 100 will vary greatly. Additionally, depending on the angle of incidence at which the incident light strikes the surface of the sensor device 100, shadows on the filter array 160 may be significant, which may result in a non-trivial modulation of the spectral response of the sensor device 100. Finally, due to geometric constraints, the combined optics of such embodiments will result in a thick stack of elements. For example, a predefined distance D is determined based on the expected angle of incidence, so the pinhole (such as the aperture defined above) has a predefined width W and a predefined thickness H. Figure 3 The options for the shape of the pinholes and the collimating pinhole elements that follow in Figures 4 to 15 below include, but are not limited to, circular, triangular, square, star, hexagonal, octagonal, and even irregular shapes dictated by the manufacturing / fabrication process. For example, the irregular structure can be a byproduct of a DRIE or wet etching process, where the irregular structure provides a rough surface that enhances / improves the absorption of incident light 180 that strikes the sidewalls of the collimating pinhole element.

[0036] Figure 4A A perspective view of a cross-sectional portion of an exemplary optical sensor is shown, the optical sensor being replaced with the incident angle device 140. Figure 3 The incident angle device 140 is a single pinhole, the incident angle device comprising an array of collimating pinhole elements (collimating elements) disposed at a predefined distance D above the filter array 160. As will be further explained below, for example, the incident angle device 140 can be configured to limit the maximum angle of light passing through the filter array 160 and the optical sensor 200. In practice, the thickness of the incident angle device 140 and the hole size of the collimating element are selected based on the filter response of the filter elements in the filter array 160. Therefore, the incident angle device 140 is configured to provide a predetermined distribution of light angles emitted from the incident angle device 140, wherein the predetermined distribution of light angles matches the desired filter response of the filter array 160.

[0037] In a specific example, the filter array 160 is formed of individual filter elements aligned (associated) with individual optical sensors of the optical sensor array 170. In another specific example, the filter array 160 is formed of individual filter elements, and multiple filter elements are aligned with a single optical sensor of the optical sensor array 170. In one example, the filter array 160 is formed of individual elements separated by boundaries or boundaries between elements in the filter array 160. In yet another specific example, the filter array 160 is formed of individual elements formed continuously in the filter array 160. Therefore, although the individual filter elements of the filter array 160 are aligned in Figure 4A Although shown as separate elements in the drawings, in reality the individual filter elements may be formed directly adjacent to each other, separated by boundaries between the individual filter elements, or separated by a combination of both (ie, some filter elements are separated from each other directly adjacent to each other).

[0038] Figure 4B Shows Figure 4A1 is a side view of a portion of an exemplary optical sensor of FIG. 1. In a specific example of implementation, the collimating elements of the incident angle device 140 are positioned at a predefined distance D above the filter array 160 such that the conditioned light 150 generated by each collimating element of the collimating array of the incident angle device 140 overlaps with the conditioned light 150 generated by the adjacent collimating elements of the collimating array of the incident angle device 140 when illuminating the filter array 160. In one example, the overlapping conditioned light can be used to provide an averaging effect for the light generated from each collimating element, thereby averaging the individual filter elements of the filter array 160 and subsequently averaging the individual sensors of the sensor array 170. In another example, the collimating elements of the incident angle device 140 are positioned substantially in direct contact with the filter array 160, assuming that the filter elements of the filter array 160 are substantially identical, such that each individual sensor element of the sensor array 170 receives conditioned light through the incident angle device 140 and the filter array 160, and the conditioned light is substantially identical to the conditioned light of the adjacent sensor elements. In the example, any variability from the angle of incidence device 140 is assumed to be effectively equal, so that the spectrum received by the various sensor elements is not “colored” by the angle of incidence device 140 .

[0039] In a specific example of implementation, the incident angle device 140 can be implemented as an opaque layer, and each collimating element of the collimating element array includes a void in the opaque layer. In one example, the collimating elements can be formed using a photolithography process method alone or in combination, such as deep reactive ion etching (DRIE), ion milling, and wet chemical etching. In another specific example of implementation examples, the collimating elements can include air voids, and in another example, the voids can include solid materials configured to allow light of a predetermined wavelength to pass. In one example, the solid material included in the collimating elements can be formed separately from the opaque layer of the incident angle device 140, and the opaque layer is formed in a secondary process around the solid collimating elements. In yet another example, the incident angle device 140 can be formed in an integral process, and each incident angle device 140 is sliced ​​from a larger precursor material and applied to the optical sensor 100 in a mechanical process. In one example of operation, the slicing of the precursor material can include sawing with a blade or a laser cutter, and before being applied to the optical sensor 100, post-processing such as chemical mechanical polishing (CMP) can be performed.

[0040] In another example of implementation, the incident angle device 140 can be formed of a predetermined material to produce a rough surface on the sidewalls of the collimating element. For example, the incident angle device 140 can include an opaque layer formed using a sputtering deposition process that is suitable for producing (relatively) large pieces of material that will be unevenly etched to produce a rough surface. Exemplary sputtering methods include ion beam sputtering, reactive sputtering, high target utilization sputtering, ion assisted deposition, high power pulsed magnetron sputtering, and gas flow sputtering.

[0041] Figure 5 A side view of another exemplary optical sensor is shown that includes a diffusing layer 190 proximate to the collimating elements of the incident angle device 140. The diffusion / diffusing layer or diffuser (also referred to as a light diffuser or optical diffuser) can be any material that diffuses or scatters light. For example, the diffused light can be provided using any translucent material, including but not limited to frosted glass, Teflon, opal glass, and gray glass located between the light source and the diffused light. In the example, the diffusing layer 190 effectively disrupts the incident light 180 before it is received at the incident angle device 140, so that the light passing through the incident angle device 140 is averaged between the incident angles of the incident light 180. In the example, when the adjusted light 150 leaves the collimating array of the incident angle device 140, the adjusted light is shown as a "light cone".

[0042] In one example, the light cones overlap when illuminating the filter array 160, and therefore, the responses from the individual optical sensors of the optical sensor array 200 may also overlap. Figure 5 As shown in , overlapping responses from optical sensors of the optical sensor array 200 may result in spatial ripples on the individual sensors. In one example, the resultant spatial ripples may be attenuated to meet the requirements of a given optical sensor device. In another example, the spatial ripples may be additionally affected by the variability of the CRA of the incident light 180 impinging on the sensor and / or the angles of the rays in the incident light 180. In yet another example, another diffuse layer that is weaker than the diffuse layer 190 is positioned between the incident angle device 140 and the modulated light 150. In one example, the diffuse layer 190 provides the modulated light 150 with a more consistent uniformity. In one example, the diffuse layer 190 is adapted to provide limited diffusion such that a suboptimal uniformity is obtained without increasing the angle of the modulated light 150.

[0043] Figure 6 A side view of another exemplary optical sensor is shown, the optical sensor comprising a Figure 5The lens array 210 of the diffuser layer 190 is provided. Each lens of the lens array 210 can be positioned to focus the incident light 180 on the incident angle device 140. By focusing the incident light 180 on each collimating element, the efficiency of the optical sensor 200 can be increased because the amount of incident light 180 reflected from the surface of the diffuser layer 190 is reduced.

[0044] Back to Figure 2 In one embodiment, optical filter 110, optical filter 120, and optical filter 130 are optimized for one of the three spectral bands, but are shuffled relative to each other when they are redundantly repeated on sensor array 170. In one example, redundant optical filter 110, redundant optical filter 120, and redundant optical filter 130 and redundant optical sensors (such as Figure 6 The optical sensor 200 in Figure 2 The shading effects and / or colors on the optical sensor discussed.

[0045] Figure 7 A side view of another exemplary optical sensor is shown, the optical sensor comprising a Figure 6 The suppression filter 220 of the lens array 210 is configured to be configured to be a filter of the optical sensor 200. The suppression filter 220 can be designed to remove the out-of-band light when the incident light 180 includes light frequencies outside the spectrum expected by the optical sensor 200. In one example, the addition of the suppression filter 220 can improve the efficiency and / or performance of the optical sensor 200.

[0046] Figure 8 1 shows a side view of another exemplary optical sensor, in which the incident angle device 140 includes a fiber optic plate 230 instead of a collimating pinhole element. A fiber optic plate (sometimes also referred to as a fiber optic panel) is a transparent plate composed of many optical fibers. By connecting many input points to corresponding output points, the fiber optic plate can provide a plurality of optical fibers from the input surface ( Figure 8 160) to the output face (the surface facing the filter array 160). Fiber optic panels can contain increasingly smaller fibers to achieve correspondingly higher spatial resolution, allowing for millions of fibers to be contained in such panels.

[0047] Fig.9AA side view of an exemplary optical sensor is shown in which the incident angle device 140 is directly adjacent to the filter array 160 such that there is substantially no space between the incident angle device 140 and the filter array 160. In one example, the pinhole element of the incident angle device 140 is aligned with individual sensor elements of the sensor array 170. In another example, multiple pinhole elements of the incident angle device 140 are aligned with a single sensor element of the sensor array 170. In yet another example, a single pinhole element of the incident angle device 140 is aligned with multiple individual sensor elements of the sensor array 170. Fig. 9B In the embodiment, the incident angle device 140 is located between the filter array 160 and the sensor array 170, so that there is substantially no space between the incident angle device 140 and the filter array 160, and there is substantially no space between the incident angle device 140 and the sensor array 170. Fig.9A and 9B The arrangement of optical sensor elements in the other figures provided is illustrative only; thus, the sensor elements may be arranged in virtually any manner, and the elements may likewise be spaced as desired to suit performance and manufacturability requirements.

[0048] Fig. 10A A top view of an exemplary incident angle device 140 is provided, where an array of pinhole elements overlays a smaller optical sensor array 170. In one example, the optical sensor array 170 is slightly smaller than the array of pinhole elements included in the incident angle device 140. In one example, each pinhole element in the incident angle device 140 is aligned with a respective element on the optical sensor array 170. In an alternative example, the output of the incident angle 140 is designed to overlap and does not need to be aligned with the sensor elements of the optical sensor array 170. In yet another example, the incident angle device 140 is a fiber optic plate or another suitable structure suitable for providing the conditioned light 150 on the optical sensor array 200. Fig. 10B Shown from Fig. 10A 4 to 8 , the incident angle device 140 is positioned a predetermined distance D from the filter array 160, which is positioned proximate to the optical sensor array 170. In one example, the projected light from each collimating element of the incident angle device 140 overlaps the projected light from one or more adjacent collimating elements.

[0049] Fig.11AAn example of a desired angle of incidence of the passing light through the pinhole element of the angle of incidence device 140 is shown, where the angle of incidence of the passing light is within the desired angle for the optical sensor 100. Also shown is an angle of incidence that produces undesirable reflected light from the sidewalls of the pinhole element of the angle of incidence device 140. For example, this undesirable reflected light can be the result of specular and / or diffuser reflections onto the inner sidewalls of the pinhole element. As discussed above, this undesirable reflected light can reduce the efficiency and / or performance of the optical sensor 100.

[0050] Fig. 11B An example of an incident angle device 140 having an absorptive or anti-reflective surface coating 240 and / or an absorptive sidewall coating 250 is provided to reduce or substantially eliminate the Fig.11A Undesirable reflected light discussed. Exemplary absorbing or anti-reflective coatings include any material with absorbing properties that can reduce reflection of incident light. Exemplary materials include, but are not limited to, low-mirror coatings, carbon nanotubes, oxide coatings, powder coatings, silicon nitride, etc. In one example, the absorbing coating can be applied in the form of a spray, deposited in a single or multiple steps, and / or passivated to provide a micro-coating with acceptable coverage, taking into account the aspect ratio of the pinhole element sidewalls and the expected performance of the coating. In another example, the anti-reflective coating is a byproduct of the DRIE etching process.

[0051] Figures 12A to 12F Examples of pinhole element shapes / structures suitable for reducing the incidence of unintended reflected light are provided; in each example, the pinhole shape is adapted to a specific angle, or a combination of angles, or even a curved shape. The resulting pinhole structure can be used as is, or can be coated, deposited, or passivated with one or more of the above-mentioned absorptive or anti-reflective coatings. Other examples include processing by etching or some other method to present a rough surface, or any other method capable of diffusing light at undesired angles. In another example, the pinhole sidewalls can be processed to present a highly reflective surface, which can then be directed away from the detector element.

[0052] In one example, deep reactive ion etching (DRIE) can be used to create pinhole structures in a silicon wafer, where, in one example, DRIE creates a scalloped surface ( Fig. 12C This can in turn reduce unwanted reflected light through a passivation effect. Figures 12A to 12E In another related example, the angle of the pinhole sidewalls is adjusted so that reflected light at angles above a predetermined amount is reflected away from the bottom of the pinhole. In another example, an absorbing coating (such as discussed in 11B above) defines the pinhole at the top and bottom of the cap or cover so that only light at a desired angle can pass through the pinhole element. In another example, the pinhole element sidewalls can be adapted to block light greater than a desired angle from leaving the pinhole element.

[0053] Various options may be used to manufacture the angle of incidence device 140. Material options include, but are not limited to, plastics, metals, ceramics, semiconductors (plates or substrates). Semiconductor options include, but are not limited to, silicon, silicon germanium, and germanium, and the angle of incidence device may be formed using drilling, laser drilling, etching (such as DRIE or wet chemistry), hot embossing, micro 3D printing, or any other suitable method (including imprinting techniques or deposition techniques). The angle of incidence may also include multiple multilayer structures or holes, thin film stacks, and structures integrated with the sensor back-end line. The angle of incidence may also consist of an orthogonal grid of reflective or absorptive plates, lines, or beams, or stacks of such structures, examples of which are described below. Fig.15 and 16 . Options for angle of incidence device 140 fabrication include mounting a previously formed structure on a wafer with multiple sensor devices 100, etching in place after attaching sensor devices 100 on a wafer, or attaching as part of the formation of a package for sensor devices 100. Options also include forming and / or attaching angle of incidence device 140 during system assembly.

[0054] Fig.13 A side view of an exemplary optical sensor is provided with an angle limiting element positioned on an incident angle device 140, wherein the incident angle device is directly adjacent to the filter array 160 such that there is substantially no space between the incident angle device 140 and the filter array 160. In one example, a primary angle limiting device 300 is positioned above the incident angle device in the optical sensor stack. In one example, the primary angle limiting device acts as a light limiting element to "pre-limit" or "pre-condition" the light before the light reaches the first surface of the incident angle device 140 such that the incident light 180 is at least partially limited. For example, if the primary angle limiting device 300 is a lens, such as Fig.13 As shown, the angle of the incident light will be limited by the amount controlled by the lens. Fig.13 In the example, the primary angle limiting device 300 limits the incident light 180 to ±40 degrees, so if the incident angle device 140 further limits the incident light 180 to ±10 degrees, limiting the incident light 180 to ±40 degrees can improve the performance of the incident angle device 140 by reducing high-angle reflections within the incident angle device 140.

[0055] Fig.14 Another exemplary optical sensor side view is provided having an angle limiting element located above the incident angle device 140. In the example, the primary angle limiting device 300 located above the incident angle device in the optical sensor stack is a conical structure that limits the incident light 180 to an incident light angle based on the angle of the conical structure and the thickness of the primary angle limiting device 300.

[0056] Fig.15 A side view of another exemplary optical sensor is provided having an incident angle device 140 formed as an incident angle stack 310. In the example, a plurality of collimating material lines are "stacked" on top to form the incident angle device 140, an example of which is shown in FIG. Fig.16 As further shown in Fig.16 In the example of , 2 layers of parallel collimation material lines can be positioned perpendicular to each other, together forming an offset rectangular collimation element. Other examples (not shown) include 3 layers of parallel collimation material lines forming a hexagonal collimation element, 4 layers of parallel collimation material lines forming an octagonal collimation element, etc.

[0057] Figures 17A to 17D An optical sensor device is shown that combines various elements integrated with an incident angle device to form an incident angle stack. Fig.17A , the collimating element / pinhole of the incident angle device 140 can be made using patterned polymers, germanium or similar materials, etc. In one example, the incident angle device 140 is integrated directly on top of the sensor device in a post-processing step. In another example, the integrated incident angle device 140 may include an additional integrated suppression filter. The suppression filter can be a bandpass filter, a longpass filter, a shortpass filter, etc. Bandpass filters selectively transmit a specific spectral range while suppressing other wavelengths, and are found in various applications, including chemistry, fluorescence microscopy, high-speed optical imaging, and spectroscopy. Longpass filters are designed to allow (relatively) long wavelengths to pass while blocking shorter wavelengths of light. A shortpass filter is a form of edge filter designed to isolate desired wavelengths in the spectrum and "saw" out undesirable wavelengths from the optical system. For example, an optical waveguide bandstop filter allows the sidelobe level to be reduced by several orders of magnitude without significantly reducing the roll-off rate of the response characteristic. The arrangement / position of the incident angle device 140 and the filter array 160 and / or the rejection filter in the incident angle stack may be varied to suit the performance parameters of the optical sensor.

[0058] Fig. 17BA transparent layer 500 is included between the incident light 180 and the incident angle device 140. The transparent layer 500 can be composed of amorphous glass (SiOx) or a similar material to pass light, for example to provide protection from mechanical stress and / or improve manufacturability. In one example, the transparent layer 500 with the integrated incident angle device 140 is attached to the top of the sensor using an adhesive 510. The adhesive 510 can include any suitable material that will provide sufficient adhesion and can additionally be selected to provide a uniform and / or predictable distance (such as the predefined distance of Figure 4) between the integrated transparent layer 500 and the filter array 160. In one example, the adhesive 510 is applied on the outside of the optical sensor, or applied under the entire surface of the integrated transparent layer 500 and the incident angle device 140. As Fig.17A As shown, the collimating element / pinhole of the angle of incidence device 140 can be made of patterned polymer, germanium or similar materials, and can contain fluorocarbon organic polymer (FOP) for example. In one example, the integrated transparent layer 500 can integrate a rejection filter or diffuser (such as a ) on the side opposite to the angle of incidence (AOI) control feature. Figure 5 The diffuser layer 190 in FIG.

[0059] Fig. 17C A shielding structure 520 is included on the rear surface of the incident angle device 140. In one example, the shielding structure 520 may comprise metal or any other suitable dark / opaque structure, and may be thin enough to block incident light 180 passing through the opaque material of the incident angle device 140 without affecting the performance of the incident angle device 140. In one example, a suitable metallic material is sputtered or deposited on the rear surface of the material comprising the incident angle device 140 using an electron beam deposition process before the transparent layer 500 / incident angle device 140 is integrated with the optical sensor array, and may be formed / etched in a complementary formation process with the collimating elements of the incident angle device 140. By including the shielding structure 520 into the incident angle stack, any incident light passing through the opaque material of the incident angle device 140 may be further attenuated or even blocked. It should be appreciated that Fig. 17C The optical device may also integrate a suppression filter or diffuser (such as Figure 5 The diffuser layer 190 in FIG. Fig. 17B As in the optical sensor of FIG. 5 , the adhesive 510 may be applied to the outside of the optical sensor, applied under the entire surface, or may be integrated into a single structure.

[0060] In applicable Figures 17A to 17DIn an example, the incident angle device 140 can be applied to the surface of the transparent layer 500 using a deposition process, a spin coating process, or an adhesive, and then etched using DRIE, wet etching, or other processes to define the collimating elements of the incident angle device 140. In one example, an etch stop layer is deposited on the surface of the transparent layer 500 before depositing the material for the incident angle device 140, thereby providing an etch stop layer, such as a nitride material, between the transparent layers 500 during the formation of the collimating elements of the incident angle device 140.

[0061] Fig.17D A modified incident angle device 530 is provided that is bonded on top of the filter and sensor array. Fig.17A In the example of the implementation shown in , the collimating element / pinhole of the incident angle device 140 can be made of patterned polymer, germanium or similar materials, and can contain fluorocarbon organic polymer (FOP). Fig. 17B In another example shown, the optical sensor may also integrate a rejection filter or diffuser (such as Figure 5 Diffusing layer 190 in FIG. Fig. 17B In a specific example of implementation, the adhesive 510 may be applied to the outside of the optical sensor, applied under the entire surface, or may be integrated into a single structure.

[0062] In a specific example of implementation and operation, an optical sensor system includes an optical sensor array and a plurality of optical filters disposed on an integrated circuit, wherein a bottom surface of the plurality of optical filters is located above a top surface of the optical sensor array. In one example, an angle of incidence layer includes a top surface, a bottom surface, and a thickness Y, wherein the bottom surface of the angle of incidence layer is located at a predetermined distance X from a top surface of the plurality of optical filters, and the angle of incidence layer includes a plurality of collimating elements, each collimating element of the angle of incidence layer having an aperture width Z.

[0063] In a specific example, the plurality of collimating elements comprises a plurality of groups of collimating elements, each collimating element of a given group having substantially the same respective aperture width Z, and the aperture width Z of each group is different from any other group of the plurality of groups of collimating elements. In another specific example, the aperture width Z, the incident angle layer thickness Y, and the predetermined distance X are adapted to limit the incident angle of light emitted from the collimating layer to below a maximum angle. In yet another example, the optical sensor system further comprises a diffusion layer having a top surface and respective bottom surfaces, the diffusion layer may be between the plurality of filters and the optical sensor array, wherein the diffusion layer bottom surface is on top of the top surfaces of the plurality of filters, or between the plurality of filters and the optical sensor array.

[0064] In a specific example, the optical sensor system can include one or more lenses for directing received light at an angle of incidence layer or at a diffuse layer. In another example, the angle of incidence layer top and bottom surfaces are between the bottom surfaces of the plurality of filters and the top surface of the optical sensor array, and in yet another example, the bottom surface of the angle of incidence layer is on top of the top surfaces of the plurality of filters.

[0065] In one specific example, the angle of incidence layer of the optical sensor system extends beyond the edge of the optical sensor array, and in another example, the angle of incidence layer incorporates a fiber optic plate. In another specific example, the top and bottom surfaces of the plurality of filters for the optical sensor system are between the bottom surface of the angle of incidence layer array and the top surface of the optical sensor array.

[0066] In another example, the optical sensor system includes one or more suppression filters, each suppression filter having a top surface and a bottom surface, wherein the top surface and the bottom surface of the suppression filter are coplanar with the top surface of the optical sensor array. In another example, each collimating element (pinhole) of the incident angle layer further has an inner sidewall, wherein the sidewall is used to form an inner void, and the inner void is one or more of a conical shape, an inverted conical shape, a serrated shape, an hourglass shape, a stacked conical shape, a sawtooth shape, a hyperbolic shape, and a modified hyperbolic shape, wherein the top of the hyperbolic surface has a smaller hole than the bottom of the hyperbolic surface, and the bottom of the hyperbolic surface further includes a constriction element.

[0067] In another specific example, the optical sensor system includes both a primary angle limiting device, which may be a single lens, and a small number of additional lenses and their collimating elements positioned atop the angle of incidence layer. In another example of the optical sensor system, the top surface of the angle of incidence layer is coupled to the bottom surface of the plurality of filters by an adhesive, wherein the adhesive is manufactured to maintain a predetermined distance D between the angle of incidence layer and the plurality of filters. The exemplary adhesive may be prefabricated into an approximate shape and size to allow the adhesive to adequately resist shrinkage of the predetermined distance d. Options for adhesives include, but are not limited to, conventional organic adhesives and silicone adhesives. The adhesive may also include multiple layers, such as a resin and adhesive interlayer and / or an adhesive polyimide interlayer. Other options include preforming the adhesive into a conventional or modified O-ring shape.

[0068] In a specific example of implementation and operation, an optical sensor system includes an incident angle layer including a primary incident angle element and a secondary incident angle element, wherein the primary incident angle element is offset from the secondary incident angle element, and wherein the primary incident angle element and the secondary incident angle element form a plurality of collimating elements.

[0069] Fig.18A method of manufacturing an optical sensor system is provided. In a specific example of implementation and operation, the method of manufacturing an optical sensor system begins at step 600, where an optical sensor array is formed on an integrated circuit. In one example, the optical sensor array is formed on top of active circuits of the integrated circuit, and in another example, the optical sensor array is formed on the back side of the integrated circuit. The method continues at step 610, where a plurality of filters are formed on the optical sensor array. In one example, the plurality of filters include Fabry-Perot interferometers configured as a pair of spaced apart partially reflective glass optical planes, a process that requires multiple deposition and lithography steps. In a related example, all or part of the Fabry-Perot interferometers are configured as multiple pairs of partially reflective glass optical planes, the reflective surfaces of the planes facing each other in a stack. In yet another example, the plurality of filters include alternative filter types, such as organic filters, or a combination of alternative filter types and Fabry-Perot interferometers.

[0070] The method continues at step 620 by adding an angle of incidence device (angle of incidence layer) over the plurality of filters. In one example, the angle of incidence layer is formed separately and adhered to the plurality of filters using an adhesive. In another example, the angle of incidence layer is formed over the plurality of filters by using an intermediate layer (such as a substantially transparent material, or a layer configured to diffuse light that passes through the plurality of filters after exiting from the angle of incidence layer). In yet another example, the angle of incidence layer is formed on a sacrificial layer that is removed after the angle of incidence layer is formed and / or adhered to the surface of the integrated circuit. In a related example, the angle of incidence layer is supported on two or more of its respective edges by depositing material and subsequently defining supports in one or more photolithography steps. In a specific example, the formation of the angle of incidence layer in step 620 can be reverse to step 610 (including the additional steps described above), with the plurality of filters formed on top of the angle of incidence layer. In an optional step 630, a diffuser layer is adhered to the angle of incidence layer. As described above, the diffuser layer may be formed on the angle of incidence layer, or formed separately and applied to the surface of the angle of incidence layer in an additional step. In optional step 640, one or more lenses (such as a lens array) are applied to the diffuser layer of step 630. In an alternative example, there is no diffuser layer step 630, and one or more lenses are applied directly to the angle of incidence layer or in a series of steps.

[0071] It should be noted that terms that may be used herein, such as bitstream, stream, signal sequence, etc. (or their equivalents) have been used interchangeably to describe digital information whose content corresponds to any of a variety of desired types (e.g., data, video, voice, text, graphics, audio, etc., any of which is generally referred to as "data").

[0072] As may be used herein, the terms "substantially" and "approximately" provide industry-accepted tolerances for their corresponding terms and / or dependencies between items. For some industries, the industry-accepted tolerances are less than one percent, and for other industries, the industry-accepted tolerances are 10% or higher. Other industries accept tolerances ranging from less than one percent to fifty percent. Industry-accepted tolerances correspond to, but are not limited to, component values, integrated circuit process variations, temperature variations, rise and fall times, thermal noise, dimensions, signal errors, discarded data packets, temperature, pressure, material composition, and / or performance indicators, etc. Within an industry, the tolerance variance of an acceptable tolerance may be greater than or less than a percentage level (e.g., a dimensional tolerance is less than + / -1%). Some dependencies between items may range from differences less than a percentage level to several percentages. Other dependencies between items may range from differences of a few percent to huge differences.

[0073] As may be used herein, the terms "configured to," "operably coupled to," "coupled to," and / or "coupled to" include direct coupling between items and / or indirect coupling between items via intermediate items (e.g., items include, but are not limited to, components, elements, circuits, and / or modules), where, as an example of indirect coupling, the intermediate items do not modify the information of a signal, but may adjust its current level, voltage level, and / or power level. As may further be used herein, inferred coupling (i.e., one element is coupled to another element by inference) includes direct and indirect coupling between two items in the same manner as "coupled to."

[0074] As may be used even further herein, the terms "configured to," "operably," "coupled to," or "operably coupled to" indicate that an item includes one or more of a power connection, input, output, etc., to perform one or more of its corresponding functions when activated, and may further include an inferred coupling to one or more other items. As may be used yet further herein, the term "associated with" includes direct and / or indirect coupling of separate items and / or one item embedded in another item.

[0075] As may be used herein, the term "compares favorably" indicates a comparison between two or more items, signals, etc., that provides a desired relationship. For example, a favorable comparison may be obtained when the desired relationship is that signal 1 has a greater amplitude than signal 2, when the amplitude of signal 1 is greater than the amplitude of signal 2, or when the amplitude of signal 2 is less than the amplitude of signal 1. As may be used herein, the term "compares unfavorably" indicates a comparison between two or more items, signals, etc., that fails to provide a desired relationship.

[0076] As may be used herein, one or more claims may include the phrase "at least one of a, b, and c" in a specific form of such general form or "at least one of a, b, or c" in such general form, with more or fewer elements than "a," "b," and "c." In either expression, the phrases are to be interpreted identically. In particular, "at least one of a, b, and c" is equivalent to "at least one of a, b, or c" and shall mean a, b, and / or c. As examples, this means: only "a," only "b," only "c," "a" and "b," "a" and "c," "b" and "c," and / or "a," "b," and "c."

[0077] As may also be used herein, the terms "processing module," "processing circuit," "processor," "processing circuitry," and / or "processing unit" may be a single processing device or a plurality of processing devices. Such processing devices may be microprocessors, microcontrollers, digital signal processors, microcomputers, central processing units, field programmable gate arrays, programmable logic devices, state machines, logic circuitry, analog circuitry, digital circuitry, and / or any device that manipulates signals (analog and / or digital) based on hard coding of circuitry and / or operating instructions. A processing module, module, processing circuitry, processing circuitry, and / or processing unit may be or further include a memory and / or an integrated memory element, which may be a single memory device, a plurality of memory devices, and / or an embedded circuitry of another processing module, module, processing circuitry, processing circuitry, and / or processing unit. Such memory devices may be read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory, and / or any device that stores digital information. It should be noted that if a processing module, module, processing circuit, processing circuit system, and / or processing unit includes more than one processing device, the processing devices may be centrally located (e.g., directly coupled together via a wired and / or wireless bus structure) or may be distributedly located (e.g., cloud computing indirectly coupled via a local area network and / or a wide area network). It is further noted that if a processing module, module, processing circuit, processing circuit system, and / or processing unit implements one or more of its functions via a state machine, analog circuit system, digital circuit system, and / or logic circuit system, then a memory and / or memory element storing corresponding operating instructions may be embedded within or external to the circuit system including the state machine, analog circuit system, digital circuit system, and / or logic circuit system. It is still further noted that the memory element may store and the processing module, module, processing circuit, processing circuit system, and / or processing unit execute hard-coded and / or operating instructions corresponding to at least some of the steps and / or functions shown in one or more of the figures. Such a memory device or memory element may be included in an article of manufacture.

[0078] One or more embodiments have been described above by means of method steps that illustrate the execution of specific functions and their relationships. For ease of description, the boundaries and order of these functional building blocks and method steps are arbitrarily defined herein. As long as the specific functions and relationships are properly performed, alternative boundaries and orders can be defined. Therefore, any such alternative boundaries or orders are within the scope and spirit of the claims. Further, for ease of description, the boundaries of these functional building blocks are arbitrarily defined. As long as certain important functions are properly performed, alternative boundaries can be defined. Similarly, flow charts can also be arbitrarily defined herein to illustrate certain important functions.

[0079] As far as the scope of use is concerned, the flow chart boundaries and order can be defined in other ways and still perform certain important functions. Therefore, such alternative definitions of functional building blocks and flow charts and sequences are within the scope and spirit of the claims. It will also be appreciated by those of ordinary skill in the art that functional building blocks and other illustrative blocks, modules and components herein can be implemented as shown or by discrete components, application specific integrated circuits, processors executing appropriate software, etc., or any combination thereof.

[0080] In addition, the flowchart may include a "start" and / or "continue" indication. The "start" and "continue" indications reflect that the steps presented may be optionally incorporated into one or more other routines or otherwise used in combination with one or more other routines. In addition, the flowchart may include an "end" and / or "continue" indication. The "end" and "continue" indications reflect that the steps presented may be optionally incorporated into one or more other routines or otherwise used in combination with one or more other routines as described and shown. In such cases, the "start" indication indicates the beginning of the first step presented, and may be before other activities not specifically shown. Further, the "continue" indication reflects that the steps presented may be performed multiple times and / or may be replaced by other activities not specifically shown. Further, although the flowchart indicates a specific order of steps, other orders may also be provided as long as the principle of causality is maintained.

[0081] One or more embodiments are used herein to illustrate one or more aspects, one or more features, one or more concepts, and / or one or more examples. A physical embodiment of an apparatus, article of manufacture, machine, and / or process may include one or more aspects, features, concepts, examples, etc. described with reference to one or more embodiments discussed herein. Further, from one figure to another, an embodiment may incorporate the same or similarly named functions, steps, modules, etc. using the same or different reference numerals, and likewise, the functions, steps, modules, etc. may be the same or similar functions, steps, modules, etc., or different functions, steps, modules, etc.

[0082] Unless otherwise specifically stated, in the figures of any accompanying drawings presented herein, the signals to, from and / or between elements may be analog or digital, continuous time or discrete time, and single-ended or differential. For example, if the signal path is shown as a single-ended path, it also represents a differential signal path. Similarly, if the signal path is shown as a differential path, it also represents a single-ended signal path. Although one or more specific architectures are described herein, other architectures using one or more data buses not explicitly shown, direct connections between elements and / or indirect couplings between other elements recognized by those of ordinary skill in the art may also be implemented.

[0083] The term "module" is used to describe one or more embodiments. A module implements one or more functions via a device such as a processor or other processing device or other hardware, which may include or operate in association with a memory storing operating instructions. A module may operate independently and / or in conjunction with software and / or firmware. As also used herein, a module may contain one or more submodules, each of which may be one or more modules.

[0084] As further used herein, computer readable memory includes one or more memory elements. A memory element can be a separate memory device, a plurality of memory devices or a group of memory locations in a memory device. Such memory devices can be read-only memory, random access memory, volatile memory, non-volatile memory, static memory, dynamic memory, flash memory, cache memory and / or any device storing digital information. A memory device can be a solid-state memory, hard drive memory, cloud memory, thumb drive, server memory, computing device memory and / or the form of other physical media for storing digital information.

[0085] Although specific combinations of various functions and features of one or more embodiments have been explicitly described herein, other combinations of these features and functions are also possible. The present disclosure is not limited to the specific examples disclosed herein, and these other combinations are expressly incorporated.

Claims

1. An optical sensor system, comprising: an optical sensor array disposed on the integrated circuit, the optical sensor array having respective top surfaces; a plurality of optical filters having respective top surfaces and respective bottom surfaces, wherein the bottom surfaces of the plurality of optical filters are positioned proximate the top surface of the optical sensor array; as well as an angle-of-incidence layer having a respective top surface, a respective bottom surface, and a respective thickness Y, wherein the bottom surface of the angle-of-incidence layer is positioned a predetermined distance X from the top surfaces of the plurality of filters, wherein the angle-of-incidence layer comprises a plurality of collimating elements, wherein each collimating element of the angle-of-incidence layer has an aperture width Z; wherein the plurality of filters or the optical sensor array is arranged to receive collimated light from the incident angle layer, and The aperture width Z, the incident angle layer thickness Y and the predetermined distance X are suitable for limiting the incident angle of light emitted from the incident angle layer to below a maximum angle.

2. An optical sensor system according to claim 1, wherein the plurality of collimating elements comprises a plurality of groups of collimating elements, wherein each collimating element of a group in the plurality of groups of collimating elements has substantially the same respective aperture width Z, wherein the aperture width Z of each group in the plurality of groups of collimating elements is different from any other group in the plurality of groups of collimating elements. 3 . The optical sensor system of claim 1 , further comprising a diffusing layer having a respective top surface and a respective bottom surface.

4. The optical sensor system of claim 3, wherein the top and bottom surfaces of the diffusion layer are located between the plurality of filters and the optical sensor array.

5. The optical sensor system of claim 3, wherein the bottom surface of the diffusing layer is on top of the top surfaces of the plurality of filters.

6. The optical sensor system of claim 1, wherein the incident angle layer top and bottom surfaces are located between the bottom surfaces of the plurality of filters and the top surface of the optical sensor array.

7. The optical sensor system of claim 1, wherein the bottom surface of the angle-of-incidence layer is on top of the top surfaces of the plurality of filters.

8. The optical sensor system of claim 7, wherein the angle of incidence layer is adapted to extend beyond one or more edges of the optical sensor array.

9. The optical sensor system of claim 1, wherein the incident angle layer comprises a fiber optic sheet.

10. The optical sensor system of claim 1, wherein the top surface and the bottom surface of the plurality of filters are located between the bottom surface of the incident angle layer and the top surface of the optical sensor array.

11. The optical sensor system of claim 1 , further comprising: One or more suppression filters, each of the one or more suppression filters having a respective top surface and a respective bottom surface, wherein the top and bottom surfaces of the one or more suppression filters are coplanar with the top surface of the optical sensor array.

12. The optical sensor system of claim 1, wherein each collimating element of the incident angle layer further comprises a sidewall, wherein the sidewall has at least one of the following forms: Conical; Inverted cone; serrated shape; hourglass shape; stacked cones; sawtooth shape; Hyperbolic shape, and A modified hyperboloid shape wherein the top of the hyperboloid has a smaller hole than the bottom of the hyperboloid, and the bottom of the hyperboloid further comprises a constriction element.

13. The optical sensor system of claim 1, further comprising: One or more lenses.

14. The optical sensor system of claim 1, wherein the top surface of the angle-of-incidence layer is coupled to the bottom surfaces of the plurality of filters by an adhesive, wherein the adhesive is adapted to maintain a predetermined distance D between the angle-of-incidence layer and the plurality of filters.

15. The optical sensor system of claim 1, further comprising: Another incident angle layer, the another incident angle layer is adjacent to the incident angle layer.

16. An optical sensor system according to claim 1, wherein the incident angle layer comprises a plurality of primary incident angle elements and a plurality of secondary incident angle elements, wherein the plurality of primary incident angle elements are adapted to deviate from the plurality of secondary incident angle elements, and wherein the primary incident angle elements and the secondary incident angle elements form the plurality of collimating elements.

17. A method for manufacturing an optical sensor system, the method comprising: forming an optical sensor array on the integrated circuit, the optical sensor array having respective top surfaces; forming a plurality of optical filters, the plurality of optical filters having respective top surfaces and respective bottom surfaces, wherein the bottom surfaces of the plurality of optical filters are positioned proximate the top surface of the optical sensor array; as well as forming an angle-of-incidence layer atop the plurality of filters, the angle-of-incidence layer having a respective top surface, a respective bottom surface, and a respective thickness Y, wherein the bottom surface of the angle-of-incidence layer is located at a respective predetermined distance X from the top surfaces of the plurality of filters, wherein the angle-of-incidence layer comprises a plurality of collimating elements, each collimating element of the plurality of angle-of-incidence layers having a respective aperture width Z; wherein the plurality of filters or the optical sensor array is arranged to receive collimated light from the incident angle layer, and The aperture width Z, the incident angle layer thickness Y and the predetermined distance X are suitable for limiting the incident angle of light emitted from the incident angle layer to below a maximum angle.

18. The method according to claim 17, further comprising: A diffusion layer is formed on top of the angle of incidence layer, the diffusion layer having a respective top surface, a respective bottom surface and a respective thickness D.

19. The method according to claim 18, further comprising: A rejection filter is formed on top of the diffusing layer, the rejection filter having a respective top surface, a respective bottom surface and a respective thickness D.

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