Photosensitive device

Abstract

A photosensitive device includes a first substrate, a second substrate, a support structure, a plurality of first microlenses, a plurality of second microlenses, a first photosensitive element, a second photosensitive element, and a collimating structure. The second substrate is disposed opposite the first substrate, with a gap between the first and second substrates. The support structure is located in the gap between the first and second substrates. The first microlenses and the second microlenses are disposed on a first side and a second side of the gap, respectively. The first photosensitive element overlaps one of the first microlenses and one of the second microlenses. The second photosensitive element overlaps another of the second microlenses. The collimating structure is located between the first substrate and the first microlens.

Description

Technical Field

[0001] The present invention relates to a photosensitive device, in particular to a photosensitive device with a microlens. Background Art

[0002] In order to increase the screen-to-body ratio of displays and achieve a narrow-frame design, under-screen fingerprint sensing technology has become a trend. Simply put, under-screen fingerprint sensing technology is to configure a photosensitive device under the display panel of an electronic device. After the electronic device detects that the user has touched the display screen, the electronic device controls the display panel to illuminate the surface of the user's finger. The sensing light will be (diffusely) reflected by the user's finger into the photosensitive device under the display panel. The reflected light is then focused on the photosensitive element through multiple microlenses and collimating structures to be converted into a digital image signal, thereby obtaining the user's fingerprint image.

[0003] Generally speaking, to recognize color images, a photosensitive device typically requires a photosensitive element designed to receive light of different wavelengths. However, light of different wavelengths exhibits different refractive indices within the same material. Specifically, longer wavelengths of light have a lower refractive index within the medium. Consequently, different colors of light have different depths of focus within the photosensitive device, impairing image recognition and light-collecting capabilities. Summary of the Invention

[0004] An object of the present invention is to provide a photosensitive device having good image sensing quality.

[0005] At least one embodiment of the present invention provides a photosensitive device, comprising a first substrate, a second substrate, a support structure, a plurality of first microlenses, a plurality of second microlenses, a first photosensitive element, a second photosensitive element, and a collimating structure. The second substrate is disposed opposite the first substrate, and a gap is formed between the first substrate and the second substrate. The support structure is located in the gap between the first substrate and the second substrate. The first microlens and the second microlens are disposed on a first side and a second side of the gap, respectively. The first photosensitive element overlaps one of the first microlenses and one of the second microlenses. The second photosensitive element overlaps another of the second microlenses. The collimating structure is located between the first substrate and the first microlens.

[0006] At least one embodiment of the present invention provides a photosensitive device comprising a first substrate, a second substrate, a plurality of first microlenses, a plurality of second microlenses, a first photosensitive element, and a second photosensitive element. The second substrate is disposed opposite the first substrate, and a gap is defined between the first and second substrates. The first microlenses and the second microlenses are disposed on a first side and a second side of the gap, respectively. The material of the first microlens is different from that of the second microlens and / or the radius of curvature of the first microlens is different from the radius of curvature of the second microlens. The first photosensitive element overlaps with one of the first microlenses. The second photosensitive element overlaps with one of the second microlenses and does not overlap with the first microlens. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Figure 1 is a cross-sectional schematic diagram of a display device according to an embodiment of the present invention.

[0008] Figure 2 yes Figure 1 A partially enlarged schematic diagram of the photosensitive device.

[0009] Figure 3 is a cross-sectional schematic diagram of a display device according to an embodiment of the present invention.

[0010] Figure 4 is a cross-sectional schematic diagram of a display device according to an embodiment of the present invention.

[0011] Figure 5 is a cross-sectional schematic diagram of a display device according to an embodiment of the present invention.

[0012] Figure 6 is a cross-sectional schematic diagram of a display device according to an embodiment of the present invention.

[0013] The reference numerals are as follows:

[0014] 10, 20, 30, 40, 50: Display device

[0015] 100: Photosensitive device

[0016] 101: first substrate

[0017] 102: Second substrate

[0018] 110: buffer layer

[0019] 112: First photosensitive element

[0020] 114: Second photosensitive element

[0021] 115rs: Finishing surface

[0022] 116: Third photosensitive element

[0023] 120: gate insulating layer

[0024] 130: interlayer insulation layer

[0025] 140,150: flat layer

[0026] 162,164,166: Flat layer

[0027] 171s, 166s, LS1s, CM1s, 250s: Surface

[0028] 171: coating

[0029] 180:Support structure

[0030] 180h,h1,h2: height

[0031] 191: first filter element

[0032] 192: Second filter element

[0033] 193: Third filter element

[0034] 200: Display panel

[0035] 220: Optical adhesive layer

[0036] 250: Cover

[0037] CM1: first collimation structure

[0038] CM2: Second collimation structure

[0039] CM3: The third collimation structure

[0040] CM1a: First hole

[0041] CM2a: Second hole

[0042] CM3a: The third hole

[0043] d: vertical spacing

[0044] D0, D1, D5, D6: distance

[0045] DE: drain

[0046] E1: first electrode

[0047] E2: Second electrode

[0048] FPi,uFPi: Fingerprint image light

[0049] GE: Gate

[0050] GP: Gap

[0051] H1,H2:Height

[0052] L1, L2, L3: light

[0053] L1, L2, L3, L4, L5: Length

[0054] LS: Light-shielding pattern layer

[0055] LSa: Hole

[0056] ML1: First microlens

[0057] ML2: Second microlens

[0058] PCL: Photoelectric conversion layer

[0059] PSL: Photosensitive layer

[0060] R1, R2: radius of curvature

[0061] S1: First side

[0062] S2: Second side

[0063] SC:Semiconductor pattern

[0064] SE: Source

[0065] T: Active components

[0066] X, Y, Z: direction DETAILED DESCRIPTION

[0067] As used herein, "about," "approximately," "substantially," or "substantially" include the stated value and the mean value within an acceptable deviation range for the particular value as determined by one of ordinary skill in the art, taking into account the measurement in question and the particular amount of error associated with the measurement (i.e., the limitations of the measurement system). For example, "about" can mean within one or more standard deviations of the stated value, or within, for example, ±30%, ±20%, ±15%, ±10%, ±5%. Furthermore, as used herein, "about," "approximately," "substantially," or "substantially" can be selected based on the acceptable deviation range or standard deviation of the measured property, cut property, or other property, and may not apply to all properties without a single standard deviation.

[0068] In the accompanying drawings, the thickness of layers, films, panels, regions, etc. is exaggerated for clarity. It should be understood that when an element such as a layer, film, region, or substrate is referred to as being "on" or "connected to" another element, it may be directly on or connected to another element, or an intermediate element may also exist. In contrast, when an element is referred to as being "directly on" or "directly connected to" another element, there is no intermediate element. As used herein, "connection" may refer to physical and / or electrical connection. Furthermore, "electrical connection" may refer to the presence of other elements between two elements.

[0069] Reference will now be made in detail to exemplary embodiments of the present invention, examples of which are illustrated in the accompanying drawings. Whenever possible, the same reference numerals are used in the drawings and the description to refer to the same or like parts.

[0070] Figure 1 is a cross-sectional schematic diagram of a display device according to an embodiment of the present invention. Figure 2 yes Figure 1 A partially enlarged schematic diagram of the photosensitive device.

[0071] Please refer to Figure 1 and Figure 2 The display device 10 includes a photosensitive device 100, a display panel 200, and a cover plate 250, which are arranged one above the other. For example, the photosensitive device 100 and the display panel 200 are bonded together using an optical adhesive layer 220 that is distributed across the entire surface. The optical adhesive layer 220 may be made of, for example, optical clear resin (OCR), optical clear adhesive (OCA), pressure sensitive adhesive (PSA), or other suitable adhesive materials.

[0072] In this embodiment, the photosensitive device 100 may be disposed on the back side of the display panel 200. For example, the photosensitive device 100 is a fingerprint recognition module, and the display device 10 may be an under-screen fingerprint recognition device, but the present invention is not limited thereto.

[0073] The display panel 200 may be, for example, an organic light emitting diode (OLED) panel, a micro light emitting diode (micro-LED) panel, a sub-millimeter light emitting diode (mini-LED) panel, or other suitable self-luminous display panel. It should be noted that, in this embodiment, the display panel 200 may also serve as an illumination light source for fingerprint recognition. However, the present invention is not limited thereto. In other embodiments, the display panel may also be a non-self-luminous display panel (e.g., a liquid crystal display panel), and the display device may utilize a backlight source to provide the illumination light required for fingerprint recognition.

[0074] The photosensitive device 100 includes a first substrate 101, a second substrate 102, a support structure 180, a plurality of first microlenses ML1, a plurality of second microlenses ML2, a photosensitive element layer PSL, and a first collimating structure CM1. In this embodiment, the photosensitive device 100 also includes a second collimating structure CM2, a third collimating structure CM3, a light-shielding pattern layer LS, a first filter element 191, a second filter element 192, and a third filter element 193.

[0075] The first substrate 101 may be a transparent or opaque substrate. For example, the first substrate 101 may comprise glass, quartz, an organic polymer, or an opaque / reflective material (e.g., a conductive material, metal, wafer, ceramic, or other suitable material), or other suitable materials. If a conductive material or metal is used, an insulating layer (not shown) is applied to the first substrate 101 to prevent short circuits.

[0076] The photosensitive element layer PSL is located above the first substrate 101 and includes a plurality of active elements and a plurality of photosensitive elements. Figure 1 , the first photosensitive element 112, the second photosensitive element 114, and the third photosensitive element 116 in the photosensitive element layer PSL are shown, and multiple active elements electrically connected to the first photosensitive element 112, the second photosensitive element 114, and the third photosensitive element 116 are omitted. In some embodiments, the first photosensitive element 112, the second photosensitive element 114, and the third photosensitive element 116 are formed together, and the first photosensitive element 112, the second photosensitive element 114, and the third photosensitive element 116 are all at the same vertical distance from the first substrate 101. In other words, in some embodiments, the first photosensitive element 112, the second photosensitive element 114, and the third photosensitive element 116 are located at the same horizontal height relative to the surface of the first substrate 101.

[0077] The first photosensitive element 112, the second photosensitive element 114 and the third photosensitive element 116 are electrically connected to the corresponding active elements. To illustrate the electrical connection between the photosensitive elements and the active elements, Figure 2 The first photosensitive element 112 is used as an example for description, and the second photosensitive element 114 and the third photosensitive element 116 also adopt the same Figure 2 The same method is used to electrically connect to the corresponding active components.

[0078] Please refer to Figure 2 The first photosensitive element 112 (which may also be the second photosensitive element 114 or the third photosensitive element 116) is electrically connected to the active element T. The active element T comprises a source electrode SE, a drain electrode DE, a gate electrode GE, and a semiconductor pattern SC. In this embodiment, the semiconductor pattern SC is a single-layer or multi-layer structure and includes amorphous silicon, polycrystalline silicon, microcrystalline silicon, single-crystalline silicon, an organic semiconductor material, an oxide semiconductor material (e.g., indium zinc oxide, indium gallium zinc oxide, or other suitable materials or combinations thereof), or other suitable materials or combinations thereof, but the present invention is not limited thereto. The semiconductor pattern SC is located on the first substrate 101. In this embodiment, a buffer layer 110 is optionally disposed between the semiconductor pattern SC and the first substrate 101. The gate electrode GE overlaps the semiconductor pattern SC and is sandwiched between the gate electrode GE and the semiconductor pattern SC by a gate insulating layer 120. In this embodiment, the gate electrode GE may be optionally disposed above the semiconductor pattern SC to form a top-gate thin-film transistor, but the present invention is not limited thereto. In other embodiments, the gate electrode GE may be disposed below the semiconductor pattern SC to form a bottom-gate thin film transistor. An interlayer insulating layer 130 is disposed on the gate electrode GE and the gate insulating layer 120. The source electrode SE and the drain electrode DE are disposed on the interlayer insulating layer 130 and are electrically connected to the semiconductor pattern SC.

[0079] The planarization layer 140 is located on the interlayer insulating layer 130. The first photosensitive element 112 (which may also be the second photosensitive element 114 or the third photosensitive element 116) is located on the interlayer insulating layer 130 and is electrically connected to the drain DE of the active element T. In this embodiment, the first photosensitive element 112 (which may also be the second photosensitive element 114 or the third photosensitive element 116) includes a first electrode E1, a photoelectric conversion layer PCL, and a second electrode E2. The photoelectric conversion layer PCL is a single-layer structure or a multi-layer structure. For example, the photoelectric conversion layer PCL is, for example, silicon-rich oxide (SRO). In other embodiments, the photoelectric conversion layer PCL is a stacked layer of a P-type semiconductor, an intrinsic semiconductor, and an N-type semiconductor. The planarization layer 150 is located on the second electrode E2.

[0080] Please continue to refer to Figure 1A first alignment structure CM1, a second alignment structure CM2, and a third alignment structure CM3 are located above the first substrate 101. The first alignment structure CM1 has a plurality of first holes CM1a corresponding to the photosensitive elements (including the first photosensitive element 112, the second photosensitive element 114, and the third photosensitive element 116), the second alignment structure CM2 has a plurality of second holes CM2a corresponding to the photosensitive elements, and the third alignment structure CM3 has a plurality of third holes CM3a corresponding to the photosensitive elements. The first holes CM1a, the second holes CM2a, and the third holes CM3a overlap in direction Z. In this embodiment, these holes may be arranged in an array, for example, in multiple columns and rows along directions X and Y, respectively, but this is not limited to the embodiment.

[0081] In this embodiment, a planar layer 162 is located on the photosensitive element layer PSL, and a first collimating structure CM1 is located on the planar layer 162. A planar layer 164 is located on the first collimating structure CM1, and a second collimating structure CM2 is located on the planar layer 164. A planar layer 166 is located on the second collimating structure CM2, and a third collimating structure CM3 is located on the planar layer 166.

[0082] The first microlens ML1 is disposed on the first substrate 101. The first collimating structure CM1 and the second collimating structure CM2 are located between the first substrate 101 and the first microlens ML1.

[0083] In this embodiment, the first microlenses ML1 can be arranged in multiple columns and rows along directions X and Y. In this embodiment, first microlenses ML1 are disposed in some of the third holes CM3a, while first microlenses ML1 are not disposed in other portions of the third holes CM3a. Therefore, in this embodiment, some photosensitive elements (e.g., the first photosensitive element 112 and the third photosensitive element 116) overlap with the first microlenses ML1 in direction Z, while some photosensitive elements (e.g., the second photosensitive element 114) do not overlap with the first microlenses ML1 in direction Z.

[0084] In some embodiments, the first microlens ML1 may be made of an organic photoresist material, but the present invention is not limited thereto.

[0085] The second substrate 102 is disposed opposite to the first substrate 101. The second substrate 102 comprises a transparent substrate. For example, the second substrate 102 comprises glass, quartz, organic polymer, or other applicable materials.

[0086] The light-shielding pattern layer LS is disposed on the second substrate 102. For example, the light-shielding pattern layer LS is disposed between the second substrate 102 and the first substrate 101. The light-shielding pattern layer LS has a plurality of holes LSa. In this embodiment, the holes LSa of the light-shielding pattern layer LS overlap with the first hole CM1a, the second hole CM2a, and the third hole CM3a in the direction Z.

[0087] The first filter element 191, the second filter element 192, and the third filter element 193 are disposed on the second substrate 102. For example, the first filter element 191, the second filter element 192, and the third filter element 193 are disposed between the second substrate 102 and the first substrate 101, and are respectively filled in the corresponding holes LSa.

[0088] The first filter element 191 overlaps the first photosensitive element 112 and is configured to pass light L1 having a first wavelength λ1. The second filter element 192 overlaps the second photosensitive element 114 and is configured to pass light L2 having a second wavelength λ2. The third filter element 193 overlaps the third photosensitive element 116 and is configured to pass light L3 having a third wavelength λ3.

[0089] In this embodiment, the first wavelength λ1 is greater than the third wavelength λ3, and the third wavelength λ3 is greater than the second wavelength λ2, but the present invention is not limited thereto. In other embodiments, the first wavelength λ1 is greater than the second wavelength λ2, and the second wavelength λ2 is greater than the third wavelength λ3. In some embodiments, light L1, light L2, and light L3 are visible light, such as green light, blue light, and red light, but the present invention is not limited thereto. In other embodiments, light L1, light L2, and light L3 may also include non-visible light, such as infrared light.

[0090] In some embodiments, a first filter element 191, a second filter element 192, and a third filter element 193 are provided to convert light into light of a predetermined wavelength, but the present invention is not limited thereto. In other embodiments, the first filter element 191, the second filter element 192, and the third filter element 193 are not required, and light of the predetermined wavelength can be obtained by selecting a light source that can emit light of the predetermined wavelength.

[0091] The cladding layer 171 is disposed on the first filter element 191 , the second filter element 192 and the third filter element 193 .

[0092] The second microlens ML2 is disposed on the second substrate 102. At least one of the first filter element 191, the second filter element 192, and the third filter element 193 is located between the second substrate 102 and the second microlens ML2.

[0093] In this embodiment, the second microlenses ML2 may be arranged in multiple columns and rows along directions X and Y. In this embodiment, some photosensitive elements (e.g., the second photosensitive element 114 and the first photosensitive element 112) overlap with the second microlenses ML2 in direction Z, while some photosensitive elements (e.g., the third photosensitive element 116) do not overlap with the second microlenses ML2 in direction Z.

[0094] In some embodiments, the second microlens ML2 may be made of an organic photoresist material, but the present invention is not limited thereto.

[0095] In this embodiment, a gap GP is defined between the first substrate 101 and the second substrate 102, where the gap GP is, for example, an air gap. The support structure 180 is located in the gap GP between the first substrate 101 and the second substrate 102. Alternatively, the thickness of the gap GP between the first substrate 101 and the second substrate 102 is defined by the thickness of the support structure 180. In this embodiment, the support structure 180 supports the gap GP between the first substrate 101 and the second substrate 102, preventing the gap GP from collapsing.

[0096] In some embodiments, the height 180h of the support structure 180 is greater than or equal to the sum of the height h1 of the first microlens ML1 and the height h2 of the second microlens ML2, but the present invention is not limited thereto. In other embodiments, a dummy first microlens ML1 is disposed below the support structure 180, and the support structure 180 is positioned above the dummy first microlens ML1. In this case, the height 180h of the support structure 180 is greater than or equal to the height h2 of the second microlens ML2. In some embodiments, the third collimating structure CM3 is relatively thin and can be omitted.

[0097] The first microlens ML1 and the second microlens ML2 are respectively disposed on the first side S1 and the second side S2 of the gap GP. In this embodiment, the first side S1 of the gap GP is the side of the gap GP closer to the first substrate 101, and the second side S2 is the side of the gap GP closer to the second substrate 102. In other words, the first microlens ML1 is disposed on the side of the gap GP closer to the first substrate 101, and the second microlens ML2 is disposed on the side of the gap GP closer to the second substrate 102. In other embodiments, the positions of the first microlens ML1 and the second microlens ML2 may be reversed.

[0098] In this embodiment, the first photosensitive element 112 overlaps one of the first microlenses ML1 and one of the second microlenses ML2 in the direction Z. The second photosensitive element 114 overlaps one of the second microlenses ML2 in the direction Z and does not overlap the first microlens ML1. The third photosensitive element 116 overlaps one of the first microlenses ML1 in the direction Z and does not overlap the second microlens ML2.

[0099] In this embodiment, the first micro-lens ML1 and the second micro-lens ML2 are convex lenses, and the focusing of the convex lenses can be calculated by Formula 1.

[0100] Formula 1

[0101]

[0102] In Formula 1, f is the focal length of the microlens, n is the refractive index, and R is the radius of curvature of the microlens.

[0103] In this embodiment, light L1, light L2, and light L3 each have different wavelengths. Light with a longer wavelength has a lower refractive index n in the medium and is more easily focused at a deeper position. In this embodiment, the curvature radius R1 of the first microlens ML1 is different from the curvature radius R2 of the second microlens ML2 to prevent light L1 and light L2 from focusing at different depths. Specifically, in this embodiment, the third wavelength λ3 of light L3 is greater than the second wavelength λ2 of light L2. Therefore, when the material of the first microlens ML1 and the second microlens ML2 are the same, the refractive index n3 of light L3 in the first microlens ML1 is less than the refractive index n2 of light L2 in the second microlens ML2. By making the curvature radius R2 of the second microlens ML2 larger than the curvature radius R1 of the first microlens ML1, the problem of light L3 focusing deeper than light L2 due to the refractive index n3 being less than the refractive index n2 is improved. In this embodiment, the light L3 passing through the first micro lens ML1 is focused on the position of the third photosensitive element 116 , and the light L2 passing through the second micro lens ML2 is focused on the position of the second photosensitive element 114 .

[0104] In addition, when the first microlens ML1 and the second microlens ML2 are combined together, the focus can be calculated by Formula 2.

[0105] Formula 2

[0106]

[0107] In Formula 2, f is the combined focal length of the first microlens ML1 and the second microlens ML2, f1 is the focal length of the first microlens ML1, f2 is the focal length of the second microlens ML2, and d is the vertical distance between the first microlens ML1 and the second microlens ML2. In this embodiment, d is much smaller than both f1 and f2, or even equal to 0. Therefore, d / f1f2 approaches 0. For example, d is less than 1 micron, while f1 and f2 are 10 to 25 microns, respectively. Therefore, Formula 2 can be further simplified to become Formula 3.

[0108] Formula 3

[0109]

[0110] In this embodiment, the first wavelength λ1 of light L1 is greater than the third wavelength λ3 of light L3 and the second wavelength λ2 of light L2. Therefore, when the material of the first microlens ML1 and the second microlens ML2 are the same, the refractive index n1 of light L1 in the first microlens ML1 or the second microlens ML2 is less than the refractive index n3 of light L3 in the first microlens ML1 and the refractive index n2 of light L2 in the second microlens ML2. By overlapping the first microlens ML1 and the second microlens ML2, the problem of light L1 being focused too deeply due to the first wavelength λ1 being greater than the third wavelength λ3 and the second wavelength λ2 is alleviated. In this embodiment, light L1 passing through the first microlens ML1 and the second microlens ML2 is focused on the first photosensitive element 112.

[0111] Based on the above, by disposing the first microlenses ML1 and the second microlenses ML2, light L1, light L2, and light L3 can be focused onto the positions of the first photosensitive element 112, the second photosensitive element 114, and the third photosensitive element 116, respectively, thereby improving the quality of image sensing. In addition, all first microlenses ML1 are formed on the same layer using the same process, and all second microlenses ML2 are formed on another layer using the same process. In other words, in this embodiment, the first microlenses ML1 and second microlenses ML2 having different radii of curvature are formed in different layers, which can reduce manufacturing costs compared to forming first microlenses ML1 and second microlenses ML2 having different radii of curvature in the same layer.

[0112] In addition, although Figure 1In the embodiment, the photosensitive device 100 is configured to receive three different wavelengths of light L1, light L2, and light L3, but the present invention is not limited thereto. In other embodiments, the photosensitive device is configured to receive at least two of the light L1, light L2, and light L3. In other words, in other embodiments, the microlens setting method includes at least two of the following: the photosensitive element simultaneously overlaps the first microlens ML1 and the second microlens ML2, the photosensitive element only overlaps the first microlens ML1, and the photosensitive element only overlaps the second microlens ML2. In other words, the present invention does not limit the photosensitive device 100 to having the three characteristics of the photosensitive element simultaneously overlapping the first microlens ML1 and the second microlens ML2, the photosensitive element only overlaps the first microlens ML1, and the photosensitive element only overlaps the second microlens ML2.

[0113] Figure 3 is a cross-sectional diagram of a display device according to an embodiment of the present invention. It must be noted that Figure 3 The implementation examples follow Figure 1 The component numbers and partial contents of the embodiments are the same or similar components, and the description of the same technical contents is omitted. For the description of the omitted parts, please refer to the above embodiments and will not be repeated here.

[0114] Figure 3 The display device 20 and Figure 1 The difference between the display device 10 and the display device 20 is that: in the display device 20, the curvature radius R1 of the first microlens ML1 is equal to the curvature radius R2 of the second microlens ML2, and the material of the first microlens ML1 is different from the material of the second microlens ML2.

[0115] In some embodiments, the material of the first microlens ML1 is adjusted to increase the refractive index n3' of the light L3 in the first microlens ML1 (e.g., greater than the refractive index n3 of the light L3 in the first microlens ML1 in the display device 10). In other embodiments, the material of the second microlens ML2 is adjusted to decrease the refractive index n2' of the light L2 in the second microlens ML2 (e.g., less than the refractive index n2 of the light L2 in the second microlens ML2 in the display device 10). In some embodiments, the materials of the first microlens ML1 and the second microlens ML2 are adjusted simultaneously.

[0116] In this embodiment, for light of the same wavelength, the refractive index of the first microlens ML1 is greater than that of the second microlens ML2. Furthermore, the refractive index of the longer-wavelength light L3 in the first microlens ML1 is approximately equal to the refractive index of the shorter-wavelength light L2 in the second microlens ML2. This improves the problem of the deeper focus depth of the light L1 compared to the light L2, caused by the third wavelength λ3 being greater than the second wavelength λ2.

[0117] In addition, although Figure 3 In the embodiment, the photosensitive device 100 is configured to receive three different wavelengths of light L1, light L2, and light L3, but the present invention is not limited thereto. In other embodiments, the photosensitive device is configured to receive at least two of the light L1, light L2, and light L3. In other words, in other embodiments, the microlens setting method includes at least two of the following: the photosensitive element simultaneously overlaps the first microlens ML1 and the second microlens ML2, the photosensitive element only overlaps the first microlens ML1, and the photosensitive element only overlaps the second microlens ML2. In other words, the present invention does not limit the photosensitive device 100 to having the three characteristics of the photosensitive element simultaneously overlapping the first microlens ML1 and the second microlens ML2, the photosensitive element only overlaps the first microlens ML1, and the photosensitive element only overlaps the second microlens ML2.

[0118] Figure 4 is a cross-sectional diagram of a display device according to an embodiment of the present invention. It must be noted that Figure 4 The implementation examples follow Figure 1 The component numbers and partial contents of the embodiments are the same or similar components, and the description of the same technical contents is omitted. For the description of the omitted parts, please refer to the above embodiments and will not be repeated here.

[0119] Figure 4 The display device 30 and Figure 1 The difference between the display device 10 and the display device 30 is that: in the display device 30, the first side S1 of the gap GP provided with the first microlens ML1 is the side of the gap GP close to the second substrate 102, and the second side S2 of the gap GP provided with the second microlens ML2 is the side of the gap GP close to the first substrate 101.

[0120] In this embodiment, the first microlenses ML1 are disposed on the second substrate 102 , and the second microlenses ML2 are disposed on the first substrate 101 .

[0121] In this embodiment, the radius of curvature R1 of the first microlens ML1 is smaller than the radius of curvature R2 of the second microlens ML2. In this embodiment, the material of the first microlens ML1 is the same as that of the second microlens ML2, but the present invention is not limited thereto. In other embodiments, the material of the first microlens ML1 is different from that of the second microlens ML2.

[0122] In addition, although Figure 4In the embodiment, the photosensitive device 100 is configured to receive three different wavelengths of light L1, light L2, and light L3, but the present invention is not limited thereto. In other embodiments, the photosensitive device is configured to receive at least two of the light L1, light L2, and light L3. In other words, in other embodiments, the microlens setting method includes at least two of the following: the photosensitive element simultaneously overlaps the first microlens ML1 and the second microlens ML2, the photosensitive element only overlaps the first microlens ML1, and the photosensitive element only overlaps the second microlens ML2. In other words, the present invention does not limit the photosensitive device 100 to having the three characteristics of the photosensitive element simultaneously overlapping the first microlens ML1 and the second microlens ML2, the photosensitive element only overlaps the first microlens ML1, and the photosensitive element only overlaps the second microlens ML2.

[0123] Figure 5 is a cross-sectional diagram of a display device according to an embodiment of the present invention. It must be noted that Figure 5 The implementation examples follow Figure 1 The component numbers and partial contents of the embodiments are the same or similar components, and the description of the same technical contents is omitted. For the description of the omitted parts, please refer to the above embodiments and will not be repeated here.

[0124] Figure 5 The display device 40 and Figure 1 The difference between the display device 10 and the display device 40 is that: in the display device 40, the first photosensitive element 112 overlaps with one of the first microlenses ML1 and one of the second microlenses ML2, and in the combination of the first microlens ML1 and the second microlens ML2 overlapping the first photosensitive element 112, the vertical distance d between the first microlens ML1 and the second microlens ML2 is equal to the focal length f1 of the first microlens ML1 plus the focal length f2 of the second microlens ML2.

[0125] In this embodiment, the first wavelength λ1 of light L1 is greater than the second wavelength λ2 of light L2. Formula 2 shows that when the vertical spacing d is equal to the focal length f1 plus the focal length f2, the combined focal length f of the first microlens ML1 and the second microlens ML2 is nearly infinite. In other words, the combination of the first microlens ML1 and the second microlens ML2 can convert light L1 into parallel light. In this embodiment, although light L1 is difficult to focus due to its long wavelength, which exceeds the process capabilities of the microlenses, the combination of the first microlens ML1 and the second microlens ML2 can improve the convergence of light L1 and achieve a collimated effect, thereby improving imaging quality.

[0126] In this embodiment, the first microlens ML1 is closer to the first photosensitive element 112 than the second microlens ML2. The focal length f2 of the second microlens ML2 is greater than the focal length f1 of the first microlens ML1, and the magnification (M) of the combination of the first microlens ML1 and the second microlens ML2 is equal to -f1 / f2, and -f1 / f2 is less than -1. In this embodiment, the radius of curvature of the first microlens ML1 is the same as the radius of curvature of the second microlens ML2, but the present invention is not limited thereto. In other embodiments, the radius of curvature of the first microlens ML1 is different from the radius of curvature of the second microlens ML2. In this embodiment, the material of the first microlens ML1 is the same as the material of the second microlens ML2, but the present invention is not limited thereto. In other embodiments, the material of the first microlens ML1 is different from the material of the second microlens ML2.

[0127] In some embodiments, the height 180h of the support structure 180 is approximately equal to the sum of the vertical spacing d, the height h1 of the first microlens ML1, and the height h2 of the second microlens ML2, but the present invention is not limited thereto. In other embodiments, a dummy first microlens ML1 is disposed below the support structure 180, and the support structure 180 is positioned on the dummy first microlens ML1. In this case, the height 180h of the support structure 180 is approximately equal to the sum of the vertical spacing d and the height h2 of the second microlens ML2.

[0128] In addition, although Figure 5 In the embodiment, the second photosensitive element 114 overlaps the first microlens ML1 but not the second microlens ML2, but the present invention is not limited thereto. In other embodiments, the second photosensitive element 114 overlaps the second microlens ML2 but not the first microlens ML1.

[0129] In summary, in the photosensitive device of the present invention, the arrangement of the first microlens and the second microlens can improve the problem of different focus depths caused by inconsistent wavelengths of light, thereby improving the quality of image sensing.

[0130] Figure 6 is a cross-sectional diagram of a display device according to an embodiment of the present invention. It must be noted that Figure 6 The implementation examples follow Figure 1 The component numbers and partial contents of the embodiments are the same or similar components, and the description of the same technical contents is omitted. For the description of the omitted parts, please refer to the above embodiments and will not be repeated here.

[0131] Please refer to Figure 6 In this embodiment, the first photosensitive element 112 , the second photosensitive element 114 , and the third photosensitive element 116 are respectively overlapped with one of the first microlenses ML1 and one of the second microlenses ML2 .

[0132] In this embodiment, the first microlens ML1 and the second microlens ML2 have a first curvature radius R1 and a second curvature radius R2 respectively, and the first curvature radius R1 and the second curvature radius R2 may be selectively the same, but not limited thereto.

[0133] For example, the display device 50 may further include a cover plate 250 on the side of the display panel 200 facing away from the photosensitive device 100 (or, the side of the second substrate 102 facing away from the first substrate 101), and the cover plate 250 has a cover plate surface 250s that is away from the second substrate 102 (or the display panel 200). The light-shielding pattern layer LS also has a surface LS1s facing the second substrate 102. A distance D0 is defined between the cover plate surface 250s of the cover plate 250 and the surface LS1s of the light-shielding pattern layer LS, and a distance D1 is defined between the surface 171s of the overcoat layer 171 and the surface LS1s of the light-shielding pattern layer LS. The hole LSa of the light-shielding pattern layer LS and the second microlens ML2 have lengths L1 and L2, respectively, along the arrangement direction (e.g., direction X). The second microlens ML2 also has a height h2 perpendicular to the arrangement direction.

[0134] In a preferred embodiment, the second curvature radius R2 of the second microlens ML2 satisfies the following relationship: And the length L1 of the hole LSa can satisfy the following relationship:

[0135]

[0136] On the other hand, the first collimating structure CM1 further includes a surface CM1s facing the gap GP. In this embodiment, a planar layer 166 is located on the surface CM1s of the first collimating structure CM1. The first through third photosensitive elements 112 through 116 each have a light-receiving surface 115rs facing the gap GP. A distance D5 is defined between the surface 166s of the planar layer 166 and the surface CM1s of the first collimating structure CM1. A distance D6 is defined between the surface CM1s of the first collimating structure CM1 and the light-receiving surfaces 115rs of the first through third photosensitive elements 112 through 116. The first microlens ML1 and the first aperture CM1a have lengths L3 and L4 (i.e., apertures) along the arrangement direction (e.g., direction X), respectively. The first microlens ML1 also has a height h1 perpendicular to the arrangement direction. The first through third photosensitive elements 112 through 116 each have a length L5 along the direction X. The length L5 is defined by, for example, the length of the interface between the second electrodes E2 of the first to third photosensitive elements 112 to 116 and the photoelectric conversion layer PCL along the direction X.

[0137] In a preferred embodiment, the first radius of curvature R1 of the first microlens ML1 satisfies the following relationship: The length L4 of the first hole CM1a can satisfy the following relationship:

[0138] Of particular note is the presence of multiple support structures 180 between the cladding layer 171 and the planar layer 166. These support structures 180, the surface 171s of the cladding layer 171, and the surface 166s of the planar layer 166 define a gap GP that accommodates the microlenses. More specifically, the gap GP separates the first microlenses ML1 and the second microlenses ML2 in the direction normal to the surface 171s of the cladding layer 171 (e.g., direction Z). The gap GP can be filled with air, a specific gas, or a near-vacuum space.

[0139] In this embodiment, the corresponding first microlens ML1 and the second microlens ML2 are spaced apart by a vertical distance d along the direction Z, and the vertical distance d satisfies the following relationship:

[0140]

[0141] When the first radius of curvature R1 of the first microlens ML1, the second radius of curvature R2 of the second microlens ML2, and the vertical spacing d between the first microlens ML1 and the second microlens ML2 are designed within the aforementioned ranges, the multiple fingerprint image light rays FPi are transmitted within the gap GP as parallel light. Therefore, variations in the gap thickness (e.g., vertical spacing d) of the gap GP do not affect the signal quality of the fingerprint image.

[0142] For example, fingerprint image light FPi incident on the photosensitive device 100 at an appropriate angle passes through the holes LSa of the light-shielding pattern layer LS and is refracted by the second microlens ML2 and the first microlens ML1. It then passes through the first holes CM1a of the first collimating structure CM1 and is transmitted to the corresponding light-receiving surfaces 115rs of the first to third photosensitive elements 112 to 116. The light-receiving surfaces 115rs are defined, for example, by the surfaces of the second electrodes E2 of the first to third photosensitive elements 112 to 116 facing the second substrate 102. In other embodiments, the light-receiving surfaces 115rs may also be defined by the surfaces of the photoelectric conversion layers PCL of the first to third photosensitive elements 112 to 116 facing the second substrate 102.

[0143] Conversely, fingerprint image light uFPi (or unintended external ambient light) entering the photosensitive device 100 at a larger incident angle, after passing through the holes LSa in the light-shielding pattern layer LS and being refracted by the second microlens ML2, is blocked by the first collimating structure CM1 and prevented from reaching the corresponding first to third photosensitive elements 112 to 116. In other words, the first and second microlenses ML1 and ML2, disposed on the two substrates and corresponding to each other, can reduce the incident angle of light reaching the first to third photosensitive elements 112 to 116. This combined design of the first and second microlenses ML1 and ML2 can limit the light-collecting range of the photosensitive device 100 and effectively suppress background noise (i.e., the sensing signal generated by unintended light), thereby increasing the signal-to-noise ratio (SNR) of the fingerprint signal. Furthermore, the design can replace portions of the light-shielding pattern layer and the spacer layers (e.g., planarization layers) used in conventional fingerprint sensing modules, thereby simplifying the manufacturing process of the photosensitive device 100.

[0144] On the other hand, since the first microlens ML1 and the second microlens ML2 of the present invention are arranged between the first substrate 101 and the second substrate 102, these microlenses can be prevented from being damaged by impact or scratches caused by unexpected external forces in subsequent processes, which helps to increase the production yield and process margin of the fingerprint sensing module.

[0145] To provide anti-counterfeiting functionality to the photosensitive device 100, a plurality of color filter patterns may be optionally provided in some of the holes LSa in the light-shielding pattern layer LS, such as, but not limited to, a first filter element 191, a second filter element 192, and a third filter element 193. In other embodiments, the fingerprint sensing module may not include these color filter patterns.

[0146] It is particularly noteworthy that, because the photosensitive device 100 of the present disclosure does not have microlenses on the side facing the display panel 200, a direct bonding process is suitable for connecting the display panel 200 and the photosensitive device 100. This reduces the phenomenon of multiple reflections of light between the display panel 200 and the photosensitive device 100, thereby significantly improving the fingerprint sensing signal of the display device 50. For example, the photosensitive device 100 and the display panel 200 are bonded together using an optical adhesive layer 220 distributed across the entire surface.

Claims

1. A photosensitive device comprising: a first substrate; a second substrate disposed opposite to the first substrate with a gap between the first substrate and the second substrate; a supporting structure located in the gap between the first substrate and the second substrate; A plurality of first micro lenses and a plurality of second micro lenses are respectively disposed on a first side and a second side of the gap; a first photosensitive element, overlapping one of the first microlenses and one of the second microlenses; a second photosensitive element, overlapping another one of the plurality of second microlenses; and a collimating structure located between the first substrate and the first microlenses; wherein the second photosensitive element does not overlap with the first microlenses; a first filter element, overlapping the first photosensitive element and configured to pass light having a first wavelength; as well as a second filter element, overlapping the second photosensitive element and configured to pass light having a second wavelength; as well as The first microlens and the second microlens are between the first filter element and the second filter element and the first photosensitive element and the second photosensitive element; The light of the first wavelength is focused to the position of the first photosensitive element, and the light of the second wavelength is focused to the position of the second photosensitive element.

2. The photosensitive device according to claim 1, further comprising: A third photosensitive element overlaps with another one of the plurality of first microlenses and does not overlap with the plurality of second microlenses.

3. The photosensitive device according to claim 2, further comprising: A third filter element overlaps the third photosensitive element and is configured to pass light with a third wavelength, wherein the first wavelength is greater than the third wavelength, and the third wavelength is greater than the second wavelength. 4 . The photosensitive device according to claim 1 , wherein a curvature radius of the plurality of second microlenses is greater than a curvature radius of the plurality of first microlenses. 5 . The photosensitive device according to claim 4 , wherein a material of the plurality of first microlenses is the same as a material of the plurality of second microlenses. 6 . The photosensitive device according to claim 1 , wherein under light of the same wavelength, a refractive index of the plurality of first microlenses is greater than a refractive index of the plurality of second microlenses. 7 . The photosensitive device according to claim 6 , wherein a curvature radius of the plurality of first microlenses is equal to a curvature radius of the plurality of second microlenses. 8 . The photosensitive device as claimed in claim 1 , wherein a vertical distance d between the first microlenses and the second microlenses is less than 1 μm.

9. The photosensitive device as claimed in claim 1 , wherein the first microlenses are closer to the first photosensitive element than the second microlenses, and a vertical spacing d between the first microlenses and the second microlenses is equal to a focal length f1 of the first microlenses plus a focal length f2 of the second microlenses, and the focal length f2 is greater than the focal length f1. 10 . The photosensitive device as claimed in claim 1 , wherein the second photosensitive element overlaps another one of the plurality of first microlenses.

11. A photosensitive device comprising: a first substrate; a second substrate disposed opposite to the first substrate with a gap between the first substrate and the second substrate; a plurality of first microlenses and a plurality of second microlenses, respectively disposed on a first side and a second side of the gap, wherein a material of the plurality of first microlenses is different from a material of the plurality of second microlenses and / or a curvature radius of the plurality of first microlenses is different from a curvature radius of the plurality of second microlenses; a first photosensitive element, overlapping one of the first microlenses and one of the second microlenses; and a second photosensitive element, overlapping one of the second microlenses and not overlapping the first microlenses; a first filter element, overlapping the first photosensitive element and configured to pass light having a first wavelength; as well as a second filter element, overlapping the second photosensitive element and configured to pass light having a second wavelength; as well as The first microlens and the second microlens are between the first filter element and the second filter element and the first photosensitive element and the second photosensitive element; The light of the first wavelength is focused to the position of the first photosensitive element, and the light of the second wavelength is focused to the position of the second photosensitive element.

12. The photosensitive device as claimed in claim 11, wherein the first photosensitive element and the second photosensitive element are located on the first substrate, the first side of the gap is the side of the gap close to the first substrate, and the second side of the gap is the side of the gap close to the second substrate.

13. The photosensitive device as claimed in claim 11, wherein the first photosensitive element and the second photosensitive element are located on the first substrate, the first side of the gap is the side of the gap close to the second substrate, and the second side of the gap is the side of the gap close to the first substrate.

14. The photosensitive device of claim 11 , wherein the first photosensitive element overlaps the one of the plurality of first microlenses and the other of the plurality of second microlenses, the plurality of first microlenses are closer to the first photosensitive element than the plurality of second microlenses, and a vertical spacing d between the plurality of first microlenses and the plurality of second microlenses is equal to the focal length f1 of the plurality of first microlenses plus the focal length f2 of the plurality of second microlenses, and the focal length f2 is greater than the focal length f1.

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