PATENT DOCUMENT

Publication Number: US-11922713-B2
Application Number: US-201916767887-A
Country: US
Kind Code: B2

Title: Under-display optical fingerprint sensor with NFV collimator and TFT/organic imager

Abstract:
An apparatus for fingerprint sensing includes a touch-display layer covered by a transparent layer. The touch-display layer can emit light to illuminate a finger surface touching the transparent layer. The touch-display layer is transparent to reflected light from the surface to underlying layers. The underlying layers include a collimator layer and a pixelated image sensor. The collimator layer can collimate the reflected light, and the pixelated image sensor can sense the collimated reflected light. The collimator can collimate the reflected light to enable a one-to-one imaging ratio between an area of the finger surface touching the transparent layer and an area of a corresponding image formed on the pixelated image sensor.

Claims:
What is claimed is: 
     
       1. An apparatus for fingerprint sensing, the apparatus comprising:
 a touch-display layer covered by a transparent layer and configured to emit light to illuminate a finger surface touching the transparent layer, wherein the touch-display layer is transparent to reflected light from the finger surface and allows the reflected light to reach underlying layers including:
 a collimator layer configured to collimate the reflected light; and 
 a pixelated image sensor configured to sense the collimated reflected light, 
 
 wherein the collimator layer comprises a micro-lens layer, the micro-lens layer comprising an array of micro-lenses with micro-lenses located in respective hexagons of a hexagonal architecture of the micro-lens layer. 
 
     
     
       2. The apparatus of  claim 1 , wherein the touch-display layer comprises an organic light-emitting diode (OILED) display. 
     
     
       3. The apparatus of  claim 2 , wherein the pixelated image sensor comprises a thin-film transistor (TFT)-based organic imager. 
     
     
       4. The apparatus of  claim 1 , wherein the collimator layer is configured to provide a narrow field-of-view within a range of +/−3 degrees. 
     
     
       5. The apparatus of  claim 1 , further comprising a micro-aperture plate including transparent glass embedded in an opaque glass, wherein the micro-lens layer is arranged on top of the micro-aperture plate and configured to separate angled-illumination reflections. 
     
     
       6. The apparatus of  claim 1 , wherein a transmission of the collimator layer is within a range of −6 dB to 0 dB. 
     
     
       7. The apparatus of  claim 1 , wherein a total feature signal-to-noise ratio (FSNR) value of the touch-display layer and the underlying layers amounts to more than 12 dB. 
     
     
       8. The apparatus of  claim 1 , wherein the finger surface touching the transparent layer includes ridges and valleys, and wherein the collimator layer is configured to separate reflections resulting from angled illumination of walls of valleys. 
     
     
       9. The apparatus of  claim 1 , wherein the collimator layer further comprises an aperture layer, wherein apertures of the aperture layer are aligned with the respective hexagons. 
     
     
       10. The apparatus of  claim 9 , wherein the collimator layer further comprises a transparent interface layer interposed between the micro-lens layer and the aperture layer. 
     
     
       11. A communication device comprising:
 a processor; and 
 a fingerprint sensing apparatus comprising:
 a collimator layer disposed under a touch-display layer and configured to collimate light; and 
 an image sensor configured to sense the collimated light, 
 
 wherein the touch-display layer is configured to emit light to illuminate a touching surface and to transmit reflected light from the touching surface to the collimator layer, and wherein the collimator layer comprises a micro-lens layer, the micro-lens layer comprising an array of micro-lenses with different micro-lenses located in respective hexagons of a hexagonal architecture of the micro-lens layer. 
 
     
     
       12. The communication device of  claim 11 , wherein the touch-display layer is covered by a transparent layer, and wherein the touching surface comprises a surface of a finger touching the transparent layer, and wherein the touching surface includes ridges and valleys, and the collimator layer is configured to separate reflections resulting from angled illumination of walls of valleys. 
     
     
       13. The communication device of  claim 11 , wherein the image sensor comprises a pixelated-image sensor comprising a thin-film transistor (TFT)-based organic imager, and wherein the touch-display layer comprises an organic light-emitting diode (OLED) display. 
     
     
       14. The communication device of  claim 11 , wherein the collimator layer is configured to provide a narrow field-of-view within a range of +/−3 degrees. 
     
     
       15. The communication device of  claim 11 , wherein the fingerprint sensing apparatus further comprises a micro-aperture plate including transparent glass embedded in an opaque glass, wherein the micro-lens layer is arranged on top of the micro-aperture plate, and wherein the micro-lens layer is configured to separate angled illumination reflections. 
     
     
       16. The communication device of  claim 11 , wherein a total feature signal-to noise-ratio (FSNR) value of the touch-display layer and at least the collimator layer amounts to more than 12 dB. 
     
     
       17. The communication device of  claim 16 , wherein a transmission of the collimator layer is within a range of −6 dB to 0 dB. 
     
     
       18. A fingerprint sensing apparatus, the apparatus comprising:
 a touch-display layer configured to emit light to illuminate a touching surface and to transmit reflected light from the touching surface to a collimator layer; 
 the collimator layer configured to collimate the reflected light; and 
 an image sensor configured to sense the collimated reflected light, 
 wherein the collimator layer comprises a micro-lens layer, the micro-lens layer comprising an array of micro-lenses with different micro-lenses located in respective hexagons of a hexagonal architecture of the micro-lens layer. 
 
     
     
       19. The apparatus of  claim 18 , wherein a transparent layer covers the touch-display layer, wherein the touching surface comprises a surface of a finger touching the transparent layer, and wherein the touching surface includes ridges and valleys, and the collimator layer is configured to separate reflections resulting from angled illumination of walls of valleys. 
     
     
       20. The apparatus of  claim 18 , wherein the collimator layer is configured to provide a narrow field-of-view within a range of +/−3 degrees, and wherein the collimator layer provides a transmission within a range of −6 dB to 0 dB. 
     
     
       21. The apparatus of  claim 18 , further comprising a micro-aperture plate including transparent glass embedded in an opaque glass, wherein the micro-lens layer is arranged on top of the micro-aperture plate, and wherein the micro-lens layer is configured to separate angled illumination reflections.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority under 35 U.S.C. § 119 from U.S. Provisional Patent Application 62/737,818 filed Sep. 27, 2018, which is incorporated herein by reference in its entirety. 
    
    
     TECHNICAL FIELD 
     The present description relates generally to sensor technology and, more particularly, to an under-display optical fingerprint sensor with narrow field-of-view (NFV) collimator and a thin-film transistor (TFT)-based organic imager. 
     BACKGROUND 
     Fingerprint sensing and matching is widely used as a reliable technique for personal identification or verification. In particular, a common approach to fingerprint identification involves scanning a sample fingerprint of a person to form an image and storing the image as a unique characteristic of the person. The characteristics of the sample fingerprint may be compared to information associated with reference fingerprints already stored in a database to determine proper identification of the person, such as for verification purposes. 
     An optical fingerprint sensor may be particularly advantageous for verification and/or authentication in an electronic device and, more particularly, a portable device, for example, a portable communication device. The optical fingerprint sensor may be carried by the housing of a portable communication device, for example, and may be sized to sense a fingerprint from a single finger. Where an optical fingerprint sensor is integrated into an electronic device or host device, for example, as noted above, the authentication can be performed quickly, for example, by a processor of the host device. The challenges facing the optical fingerprint sensor include consistency in performance over time, as the glass-air interfaces are not stable enough for small area matching. On the other hand, the large-area sensors using complementary metal-oxide-semiconductor (CMOS) are not cost effective. Separation of different reflection rays at various angles is another challenge, as many illumination patterns have to be used to separate the reflection rays, which leads to a long (e.g., a few seconds) image capture time. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Certain features of the subject technology are set forth in the appended claims. However, for purposes of explanation, several embodiments of the subject technology are set forth in the following figures. 
         FIGS.  1 A- 1 B  are diagrams illustrating an example of an under-display optical fingerprint sensor and a corresponding signal-level chart, in accordance with one or more aspects of the subject technology. 
         FIGS.  2 A- 2 B  are diagrams illustrating an example of an under-display optical fingerprint sensor and a corresponding signal-level chart, in accordance with one or more aspects of the subject technology. 
         FIG.  3    is a chart illustrating a signal-to-noise characteristic of an example narrow field-of-view filter (NFVF), in accordance with one or more aspects of the subject technology. 
         FIGS.  4 A- 4 B  are diagrams illustrating cross-sectional views of examples of a fiber-optics plate and a micro-aperture array. 
         FIGS.  5 A through  5 C  are a cross-sectional view of an example micro-lens array structure, an example array configuration and a corresponding chart, in accordance with one or more aspects of the subject technology. 
         FIG.  6    is a flow diagram illustrating an example method for providing an under-display optical fingerprint sensor, in accordance with one or more aspects of the subject technology. 
         FIG.  7    is a block diagram illustrating a wireless communication device, within which one or more aspects of the subject technology can be implemented. 
     
    
    
     DETAILED DESCRIPTION 
     The detailed description set forth below is intended as a description of various configurations of the subject technology and is not intended to represent the only configurations in which the subject technology may be practiced. The appended drawings are incorporated herein and constitute part of the detailed description. The detailed description includes specific details for the purpose of providing a thorough understanding of the subject technology. However, the subject technology is not limited to the specific details set forth herein and may be practiced without one or more of the specific details. In some instances, structures and components are shown in a block diagram form in order to avoid obscuring the concepts of the subject technology. 
     The subject technology is directed to an apparatus for fingerprint sensing with a narrow field-of view (NFV) collimator and an organic imager. The apparatus includes a touch-display layer, a collimator layer and a pixelated image sensor. The touch-display layer can be an organic light-emitting diode (OLED) display that is covered by a transparent layer (e.g., a cover glass layer) and can emit light to illuminate a surface touching the transparent layer and allows transmission of reflected light from the surface to underlying layers including the collimator layer and the organic imager. The collimator layer can collimate the reflected light, and the organic imager is a pixelated image sensor that can sense the collimated reflected light. 
     In one or more implementations, the collimator collimates the reflected light to enable a one-to-one imaging ratio between an area of the finger surface touching the transparent layer and an area of a corresponding image formed on the pixelated image sensor. In other words, the reflected light reaching a pixel of the organic imager through the collimator layer is transmitted through an area of the organic imager approximately equal to an area of the pixel. The pixelated image sensor can be a thin-film transistor (TFT)-based organic imager. In some embodiments, the collimator layer is a fiber-optics plate made of a collection of optical fiber films bundled with an opaque separator material. In one or more implementations, the collimator layer is a micro-aperture plate including transparent glass or resin embedded in an opaque glass or resin material. The collimator layer of the subject technology can achieve a NFV of approximately +/−3 degrees and a transmission within a range of about −6 dB to 0 dB. 
     In some implementations, a micro-lens layer is formed on top of the micro aperture plate to separate angled illumination reflections. A total feature signal-to-noise ratio (FSNR) value of the touch-display layer and the underlying layers amounts to more than about 12 dB. The surface touching the transparent layer is a surface of a human finger including ridges and valleys, and the collimator layer&#39;s purpose is to separate weak reflections resulting from angled illumination of walls of valleys. 
       FIGS.  1 A- 1 B  are diagrams illustrating an example of an under-display optical fingerprint sensor  110  and a corresponding signal-level chart  100 B, in accordance with one or more aspects of the subject technology. The cross-sectional view of the under-display optical fingerprint sensor  110  (hereinafter “fingerprint sensor  110 ”) is shown in diagram  100 A, which also shows a human finger  102  (hereinafter “finger  102 ”). The touch surface of the finger  102  is referred to as a “touching surface” or just a “surface” touching the fingerprint sensor  110 . 
     The fingerprint sensor  110  includes a transparent layer  120 , an optical adhesive layer  122 , a touch-display layer  130 , a collimator layer  140  and an image sensor  150 . The transparent layer  120  can be a glass cover or any other transparent layer that is used to protect the touch-display layer  130 . The transparent layer  120  can be transparent to lights within the visible spectrum. In some implementations, the transparent layer  120  can be further transparent to ultra-violet (UV) and/or infra-red light (IR) as well. The transparent layer  120  can be attached to the touch-display layer  130  via the optical adhesive layer  122 . 
     The touch-display layer  130  is transparent to reflected light from the touching surface to underlying layers and can be made of an organic light-emitting diode (OLED). An OLED includes an emissive electroluminescent layer, which is a film of an organic compound that emits light in response to an electric current. This layer of organic compound is situated between two electrodes, of which at least one is a transparent electrode, for example, made of indium-tin oxide (ITO). OLEDs are employed to create digital displays in a variety of devices and/or systems such as television screens, computer monitors, portable communication devices such as mobile phones, handheld game consoles and other electronic displays. The touch-display layer  130  can emit light (e.g., visible light) to illuminate the touching surface. 
     The collimator layer  140  is an important component of the fingerprint sensor  110 , which is of particular interest in the subject technology and will be discussed in more detail herein. The collimator layer  140  is configured so that it can provide a one-to-one imaging ratio between an area of the finger surface touching the transparent layer  120  and an area of a corresponding image formed on the image sensor  150 . The image sensor  150  is a TFT-based organic imager. A TFT-based organic imager is an organic imager that is fabricated on a TFT-based electronic readout backplane. The organic imager can be an array of organic semiconductor photodiodes. The organic semiconductor photodiodes can be made of, for example, a stack of evaporated ultrathin (e.g., &lt;100 nm) films of an organic substance such as chloro-boron (e.g., SubPc/C-60), which is sensitive in a wavelength range of about 300 nm to 650 nm. 
     The finger  102  is considered to be a normal (e.g., not wet or dry) finger and when touching the fingerprint sensor  110 , presents a ridge region  104  and a valley region  106  to the transparent layer  120 . In the valley region  106 , the light emitted by touch-display layer  130  can be reflected from a glass-air interface at a top surface of the transparent layer  120  as a specular reflection component  103  or enter the finger and be reflected back at some point within the finger tissue as a remission reflection component  105 . In the valley region  106 , there may also be wall reflections from the skin of the finger  102  from angle-illumination rays; this component is typically weak compared to the other components. In the ridge region  104 , the light emitted by touch-display layer  130  can be reflected from the touching surface of the finger  102  as a remission reflection component  107 . When the finger is wet, the space between the top surface of the transparent layer  120  and the valley region  106  of the finger  102  may be filled with sweat resulting in an additional specular reflection component (not shown for simplicity). When the finger is dry, on the other hand, additional specular reflection can be produced in the ridge region  104 . 
     The chart  100 B shown in  FIG.  1 B  depicts plots  160 ,  162  and  170 . The plot  160  depicts variation as a function distance of the specular reflection component  103  of  FIG.  1 A . The distance can be measured from a reference point on the image sensor  150  along the axis X shown in  FIG.  1 A . The specular reflection signal of plot  160  peaks at X values corresponding to the valley region  106  and is minimum (e.g., zero) at X values corresponding to the ridge region  104 . The plot  162  corresponds to the remission reflection components (e.g.,  105  and  107 ). The remission reflection signal of plot  162  has nonzero values everywhere and peaks at X values corresponding to the ridge region  104 . The total reflection signal of plot  170  is the sum of the specular reflection signal and the remission reflection signal of plots  160  and  162 , respectively. An important feature of the total reflection signal of plot  170  is a feature signal parameter, which is defined as the peak-to-peak amplitude value of the total reflection signal of plot  170 . 
       FIGS.  2 A- 2 B  are diagrams illustrating an example of a fingerprint sensor  210  and a corresponding signal-level chart  200 B, in accordance with one or more aspects of the subject technology. The fingerprint sensor  210  shown in the cross-sectional view  200 A of  FIG.  2 A  is similar to the fingerprint sensor  110  of  FIG.  1 A  and includes the touch-display layer  130 , the collimator layer  140  and the image sensor  150 . The collimator layer  140  is also referred to as a narrow field-of-view filter (NFVF). This is because the collimator layer  140  allows a narrow beam of light to pass through and reach the image sensor  150 . For example, the collimator layer  140  can be made to have a one-to-one image ratio between the touch-display layer  130  and the image sensor  150 . For the one-to-one image ratio, the image of a distance (d) on the touch-display layer  130  would be the same size (d) on the image sensor  150 .  FIG.  2 A  shows filtering of reflection rays  212  and  214  by the collimator layer  140 . The reflection rays  212  and  214  are, respectively, from the ridge region  104  and the valley region  106  of the finger  102 . 
     The chart  200 B of  FIG.  2 B  shows results of an analysis of an example image  205  of a fingerprint provided by the fingerprint sensor  110 . The chart  200 B depicts a plot  220  of a noise level and a plot  252  of the total reflection signal. On the total reflection signal of the plot  220 , the peak-to-peak value represents a difference between a valley signal (Valley signal ) and a ridge signal (Ridge signal ). The Valley signal  corresponds to the reflection rays  214  of  FIG.  2 A  and the Ridge signal  corresponds to the reflection rays  212  of  FIG.  2 A . The total reflection signal of plot  252  and the noise level depicted by the plot  220  can be represented by an FSNR parameter defined as:
 
FSNR=20 log(Valley signal −Ridge signal )/Noise  (Eq. 1)
 
where Noise is the noise level depicted by the plot  220 . An example value of the FSNR parameter for a normal finger can be about 20 dB, but in general, the value of the FSNR parameter can be more than 12 dB. The example 20 dB value is for a link budget based on example parameter values including a specular reflection level of about −30 dB, a remission reflection level of about −9 dB, a finger thinness and display blurring of about −15 dB, an NFVF transmission of about −6 dB, a display transmission of about −20 dB, a display illumination intensity of about +16.5 dB and an electronic noise of about −6 dB.
 
       FIG.  3    is a chart illustrating a signal-to noise characteristic  300  of an example NFVF, in accordance with one or more aspects of the subject technology. The NFVF is a collimator of the subject technology, for example, the collimator layer  140  of  FIG.  2 A . The signal-to noise characteristic  300  shown in  FIG.  3    depicts an example of the FSNR parameter expressed in the (Eq. 1) above and may corresponds to a normal finger (not dry and not wet). The numbers shown on the vertical and horizontal axes of the chart are merely example values of FSNR and NFVF values, respectively, and may depend on a number of factors including material, thickness and geometry of the architecture of the collimator layer and other parameters. The signal-to-noise characteristic  300  includes three different regions  302 ,  304  and  306 . The regions  302  and  306  are a low-signal level region and a high-blurring region, respectively. In other words, in the region  302  the field-of-view of the NFVF is less than about 2.2 degrees, which is less than sufficient for a reasonable signal level. In the region  306 , however, the field-of-view of the NFVF is larger than about 4.6 degrees, which allows for high blurring. Based on simulation results, the region  304  is the optimized operation region, for which the NFVF has an FSNR parameter more than 12 dB (e.g., 20 dB) and a field-of-view within a range of about 2.2-4.6 degrees. As mentioned above, it is understood that the value of the field-of-view can depend on many factors including, thickness, material and geometry of the architecture, however, it may be possible to optimize field-of-view to achieve an appropriate resolution (e.g., 50 μm) on the touch plain or the image plain. In some implementations, dry finger conditions may cause a notch in the FSNR curve that has to be considered for an optimized NFVF field-of-view selection. 
       FIGS.  4 A- 4 B  are diagrams illustrating cross-sectional views of examples of a fiber-optics plate  400 A and a micro-aperture array  400 B, respectively. The cross-sectional view of the fiber-optics plate  400 A shown in  FIG.  4 A  depicts a number of optical fiber sections  410  separated by filler sections  420  (e.g., opaque sections) that form the fiber-optics plate  400 A. Each optical fiber section  410  includes a core region  412  and a clad region  414 . An optical ray  402  entering the core region  412  can be reflected from the clad region  414 . Only rays entering the core region at an angle α less than or equal to α max  (cut-off angle), such as an optical ray  404 , can exit the fiber-optics plate  400 A. The value of the α max  is expressed as:
 
α max =sin −1 [( n   core   2   −n   cladding   2 )/ n]   (Eq. 2)
 
where n is the index of refraction of the filler sections  420 . The transmission at normal incidence of the fiber-optics plate  400 A depends on the fill factor of the optical fiber section.
 
       FIG.  4 B  shows the cross-sectional view of the micro-aperture array  400 B. The micro-aperture array  400 B is formed of an array of transparent regions  450  (e.g., micro-apertures) separated by opaque regions  460 , which can be made of glass or resin material. The value of the maximum angle  452  (α max ) for the micro-aperture array  400 B is expressed as:
 
α max =tan −1 ( W/D )  (Eq. 3)
 
Where W is the width of the transparent region  450  and D is the thickness of the micro-aperture array  400 B. The transmission at normal incidence of the micro-aperture array  400 B depends on the fill factor of the micro apertures (e.g., transparent regions  450 ). For the fiber-optics plate  400 A and the micro-aperture array  400 B, to achieve a field-of-view (FOV) of about +/−2.8 degrees, a thickness (D) has to be more than about 350 μm. The subject technology can reduce this thickness drastically, as described herein.
 
       FIGS.  5 A through  5 C  are a cross-sectional view of an example micro-lens array structure  500 A, an example array configuration  500 B and a corresponding chart  500 C, in accordance with one or more aspects of the subject technology. The cross-sectional view of the micro-lens array structure  500 A of  FIG.  5 A  shows a micro-lens layer  510  and an aperture layer  530  coupled via a transparent interface layer  520 . The micro-lens layer  510  includes an array of micro-lenses (e.g., spherical micro-lenses)  512  made of glass or a transparent polymer. 
     In some implementations, the micro-lens layer  510  may be assembled on top of the transparent interface layer  520  (e.g., a plastic substrate) and then be placed over the aperture layer  530 , which can be separately formed (e.g., deposited) on a corresponding substrate (e.g., a flex). The aperture layer  530  includes opaque sections  532  and apertures  534  (e.g., openings). The aperture layer  530  can be formed using a suitable deposition technique, and the apertures  534  can be created in the deposited opaque layer using, for example, a lithographic technique such as optical lithography technique. In some implementations, a total thickness (T) of the micro-lens array structure  500 A of the subject technology can be about 100 μm, which is significantly smaller than the thickness of the fiber-optics plate  400 A and the micro-aperture array  400 B described above with respect to  FIGS.  4 A and  4 B . Normal rays  502  can be converged by the micro-lenses  512  and be transmitted through the apertures  534 . However, oblique rays  504  are converged and then filtered by the opaque sections  532  of the aperture layer  530 . This feature of optimizing transmission of the normal rays  502  by micro-lens array structure  500 A is an important aspect of micro-lens array structure  500 A. For example, the micro-lens array structure  500 A can filter out reflection from angled illumination of walls of the touching surface in the valley region (e.g.,  106  of  FIG.  1 A ). 
     The array configuration  500 B shown in  FIG.  5 B  is a top view and depicts a hexagonal configuration of the micro-lens array  510 , where the micro-lenses  512  are located in a hexagon  515  of the hexagonal configuration. In some implementations, an array pitch represented by a distance (d) between the centers of the micro-lenses  512  can be about 12 μm. Also shown in  FIG.  5 B  are the top views of the apertures  534  of the aperture layer  530  of  FIG.  5 A . 
     The chart  500 C shown in  FIG.  5 C  depicts a plot  540  of a normalized transmission versus angle (in degrees) of incidence of the light rays (e.g.,  504 ). The normalized transmission shown by the plot  540  corresponds to an air interface and a total thickness (T) of about 105 μm. The point  542  on the plot  540  signifies a viewing angle of about +/−5 degrees, which is associated with a transmission of about 0.5 (e.g., 50% transmission). 
       FIG.  6    is a flow diagram illustrating an example method  600  for providing a fingerprint sensor  110  of  FIG.  1 A , in accordance with one or more aspects of the subject technology. The method  600  includes providing a touch-display layer (e.g.,  130  of  FIG.  1 A ) to emit light to illuminate a touching surface (e.g., surface of  102  of  FIG.  1 A ) and to transmit reflected light (e.g.,  212  and  214  of  FIG.  2 A ) from the touching surface to a collimator layer (e.g.,  140  of  FIG.  1 A ) ( 602 ). The method  600  further includes coupling the collimator layer to the touch-display layer to collimate the reflected light ( 604 ), and coupling an image sensor (e.g.,  150  of  FIG.  1 A ) to sense the collimated light ( 606 ). The collimator layer is configured to collimate the reflected light to enable a one-to-one imaging ratio between an area of the finger surface touching the transparent layer and an area of a corresponding image formed on the image sensor ( 608 ). 
       FIG.  7    is a block diagram illustrating a wireless communication device, within which one or more aspects of the subject technology can be implemented. In one or more implementations, the wireless communication device  700  can be a smart phone or a smart watch that hosts an apparatus of the subject technology including an under-display optical fingerprint sensor. The wireless communication device  700  may comprise a radio-frequency (RF) antenna  710 , duplexer  712 , a receiver  720 , a transmitter  730 , a baseband processing module  740 , a memory  750 , a processor  760 , a local oscillator generator (LOGEN)  770 , and one or more transducers  780 . In various embodiments of the subject technology, one or more of the blocks represented in  FIG.  7    may be integrated on one or more semiconductor substrates. For example, the blocks  720 - 770  may be realized in a single chip or a single system on a chip, or may be realized in a multichip chipset. 
     The receiver  720  may comprise suitable logic circuitry and/or code that may be operable to receive and process signals from the RF antenna  710 . The receiver  720  may, for example, be operable to amplify and/or down-convert received wireless signals. In various embodiments of the subject technology, the receiver  720  may be operable to cancel noise in received signals and may be linear over a wide range of frequencies. In this manner, the receiver  720  may be suitable for receiving signals in accordance with a variety of wireless standards, Wi-Fi, WiMAX, Bluetooth, and various cellular standards. In various embodiments of the subject technology, the receiver  720  may not use any saw-tooth acoustic wave (SAW) filters and few or no off-chip discrete components such as large capacitors and inductors. 
     The transmitter  730  may comprise suitable logic circuitry and/or code that may be operable to process and transmit signals from the RF antenna  710 . The transmitter  730  may, for example, be operable to up-convert baseband signals to RF signals and amplify RF signals. In various embodiments of the subject technology, the transmitter  730  may be operable to up-convert and amplify baseband signals processed in accordance with a variety of wireless standards. Examples of such standards may include Wi-Fi, WiMAX, Bluetooth, and various cellular standards. In various embodiments of the subject technology, the transmitter  730  may be operable to provide signals for further amplification by one or more power amplifiers. 
     The duplexer  712  may provide isolation in the transmit band to avoid saturation of the receiver  720  or damaging parts of the receiver  720 , and to relax one or more design requirements of the receiver  720 . Furthermore, the duplexer  712  may attenuate the noise in the receive band. The duplexer may be operable in multiple frequency bands of various wireless standards. 
     The baseband processing module  740  may comprise suitable logic, circuitry, interfaces, and/or code that may be operable to perform processing of baseband signals. The baseband processing module  740  may, for example, analyze received signals and generate control and/or feedback signals for configuring various components of the wireless communication device  700 , such as the receiver  720 . The baseband processing module  740  may be operable to encode, decode, transcode, modulate, demodulate, encrypt, decrypt, scramble, descramble, and/or otherwise process data in accordance with one or more wireless standards. 
     The processor  760  may comprise suitable logic, circuitry, and/or code that may enable processing data and/or controlling operations of the wireless communication device  700 . In this regard, the processor  760  may be enabled to provide control signals to various other portions of the wireless communication device  700 . The processor  760  may also control transfer of data between various portions of the wireless communication device  700 . Additionally, the processor  760  may enable implementation of an operating system or otherwise execute code to manage operations of the wireless communication device  700 . In one or more implementations, the processor  760  can be used to process signals of the under-display fingerprint sensor of the subject technology (e.g., signals from the image sensor  150  of  FIG.  1 A ) to generate a fingerprint image and compare the fingerprint image with a number of reference finger prints stored in a database to identify and/or authenticate a person associated with the finger print. 
     The memory  750  may comprise suitable logic, circuitry, and/or code that may enable storage of various types of information such as received data, generated data, code, and/or configuration information. The memory  750  may comprise, for example, RAM, ROM, flash, and/or magnetic storage. In various embodiments of the subject technology, information stored in the memory  750  may be utilized for configuring the receiver  720  and/or the baseband processing module  740 . In some implementations, the memory  750  may store image information from processed and/or unprocessed fingerprint images of the under-display fingerprint sensor of the subject technology. The memory  750  may also include one or more databases of reference finger prints that can be used to identify and/or authenticate a person associated with the finger print. 
     The local oscillator generator (LOGEN)  770  may comprise suitable logic, circuitry, interfaces, and/or code that may be operable to generate one or more oscillating signals of one or more frequencies. The LOGEN  770  may be operable to generate digital and/or analog signals. In this manner, the LOGEN  770  may be operable to generate one or more clock signals and/or sinusoidal signals. Characteristics of the oscillating signals such as the frequency and duty cycle may be determined based on one or more control signals from, for example, the processor  760  and/or the baseband processing module  740 . 
     In operation, the processor  760  may configure the various components of the wireless communication device  700  based on a wireless standard according to which it is desired to receive signals. Wireless signals may be received via the RF antenna  710 , amplified, and down-converted by the receiver  720 . The baseband processing module  740  may perform noise estimation and/or noise cancellation, decoding, and/or demodulation of the baseband signals. In this manner, information in the received signal may be recovered and utilized appropriately. For example, the information may be audio and/or video to be presented to a user of the wireless communication device, data to be stored to the memory  750 , and/or information affecting and/or enabling operation of the wireless communication device  700 . The baseband processing module  740  may modulate, encode, and perform other processing on audio, video, and/or control signals to be transmitted by the transmitter  730  in accordance with various wireless standards. 
     In one or more implementations, the transducers  780  may include the under-display fingerprint sensor of the subject technology (e.g.,  110  of  FIG.  1 A ). The under-display optical fingerprint sensor of the subject technology can be readily integrated into the wireless communication device  700 , in particular, when the wireless communication device  700  is a smart mobile phone or a smart watch. 
     The previous description is provided to enable any person skilled in the art to practice the various aspects described herein. Various modifications to these aspects will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other aspects. Thus, the claims are not intended to be limited to the aspects shown herein, but are to be accorded the full scope consistent with the language claims, wherein reference to an element in the singular is not intended to mean “one and only one” unless specifically so stated, but rather “one or more.” Unless specifically stated otherwise, the term “some” refers to one or more. Pronouns in the masculine (e.g., his) include the feminine and neuter genders (e.g., her and its) and vice versa. Headings and subheadings, if any, are used for convenience only and do not limit the subject disclosure. 
     The predicate words “configured to,” “operable to,” and “programmed to” do not imply any particular tangible or intangible modification of a subject, but, rather, are intended to be used interchangeably. For example, a processor configured to monitor and control an operation or a component may also mean the processor being programmed to monitor and control the operation or the processor being operable to monitor and control the operation. Likewise, a processor configured to execute code can be construed as a processor programmed to execute code or operable to execute code. 
     A phrase such as an “aspect” does not imply that such aspect is essential to the subject technology or that such aspect applies to all configurations of the subject technology. A disclosure relating to an aspect may apply to all configurations, or one or more configurations. A phrase such as an aspect may refer to one or more aspects and vice versa. A phrase such as a “configuration” does not imply that such configuration is essential to the subject technology or that such configuration applies to all configurations of the subject technology. A disclosure relating to a configuration may apply to all configurations, or one or more configurations. A phrase such as a configuration may refer to one or more configurations and vice versa. 
     The word “example” is used herein to mean “serving as an example or illustration.” Any aspect or design described herein as “example” is not necessarily to be construed as preferred or advantageous over other aspects or designs. 
     All structural and functional equivalents to the elements of the various aspects described throughout this disclosure that are known or later come to be known to those of ordinary skill in the art are expressly incorporated herein by reference and are intended to be encompassed by the claims. Moreover, nothing disclosed herein is intended to be dedicated to the public regardless of whether such disclosure is explicitly recited in the claims. No claim element is to be construed under the provisions of 35 U.S.C. § 112, sixth paragraph, unless the element is expressly recited using the phrase “means for” or, in the case of a method claim, the element is recited using the phrase “step for.” Furthermore, to the extent that the term “include,” “have,” or the like is used in the description or the claims, such term is intended to be inclusive in a manner similar to the term “comprise” as “comprise” is interpreted when employed as a transitional word in a claim.

Metadata:
Filing Date: 20190702
Publication Date: 20240305
Grant Date: 20240305
Priority Date: 20180927
Inventors: YEKE YAZDANDOOST, MOHAMMAD
GOZZINI, GIOVANNI
SETLAK, DALE
Assignee: APPLE INC
CPC Classifications: [{"code": "G06V40/1318", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06F3/0421", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K30/80", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06V40/1324", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06V40/1318", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06V40/1318", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06V40/1318", "inventive": true, "first": true, "tree": "[]"}, {"code": "G06V40/1359", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02E10/549", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06F3/0421", "inventive": true, "first": false, "tree": "[]"}, {"code": "Y02E10/549", "inventive": false, "first": false, "tree": "[]"}, {"code": "G06V40/1359", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06V40/1324", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/30", "inventive": true, "first": false, "tree": "[]"}, {"code": "G06F3/0421", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K30/80", "inventive": true, "first": false, "tree": "[]"}, {"code": "H10K50/30", "inventive": true, "first": false, "tree": "[]"}]
Family ID: 67470658