Photosensitive imaging device and preparation method thereof

Abstract

The invention relates to a photosensitive imaging device, which comprises a substrate, a plurality of light-emitting diodes and a shading layer, and optionally comprises a flat layer and / or an anti-scraping layer. Wherein the plurality of light emitting diodes are arranged on the substrate; the shading layer is arranged on the plurality of light-emitting diodes and is provided with a plurality of first open holes, and the plurality of first open holes respectively correspond to the light-emitting areas of the plurality of light-emitting diodes; the selective flat layer may be disposed between the plurality of light emitting diodes and / or between the substrate and the light shielding layer if the selective flat layer is not removed after the plurality of first openings are formed. The selective scratch-resistant layer is disposed on the light-shielding layer. In addition, the invention also relates to a method for preparing the photosensitive imaging device.

Description

Technical Field

[0001] The present invention relates to a photosensitive imaging device and a preparation method thereof, in particular to a photosensitive imaging device capable of limiting the light emitting angle of a light emitting diode and a preparation method thereof. Background Art

[0002] Imaging devices using photosensitive materials, such as optical printers, can be divided into two categories, one using indirect imaging and the other using direct imaging. The main components of the photosensitive imaging device using indirect imaging include a print head composed of a laser scanning module or a light-emitting diode array, an intermediate carrier of the image made of photosensitive material, and a non-photosensitive output medium. The imaging process of this type of device is that the print head forms a latent image on an intermediate carrier, such as a cylindrical photosensitive drum or photosensitive belt, applies toner to develop the image, and then transfers the image to a non-photosensitive output medium - usually paper or film - through transfer. The photosensitive imaging device using direct imaging usually also includes a print head with a light-emitting diode array and an output medium containing photosensitive material. The difference from the indirect imaging device is that its output medium contains photosensitive material. The imaging process is that the print head exposes the photosensitive material on the output medium with light of different intensities and wavelengths to form a latent image. The output medium containing the photosensitive material may be a monochrome, multi-color, or full-color photosensitive paper, photosensitive film, or photosensitive sheet. In the subsequent development process, the latent image can be developed into a monochrome or color image by applying pressure or other methods on the output medium. In order to improve the quality of imaging, conventional imaging devices must focus the light emitted by the LED and limit the light emitting angle of the LED, thereby controlling the size of the light spot projected on the photosensitive material, thereby achieving a higher resolution.

[0003] In the related art, European patent EP1059171A1 proposes a method of using a cylindrical lens array to limit the light-emitting angle of a light-emitting diode. However, since the intensity of the light emitted by the light-emitting diode will be significantly attenuated after passing through the cylindrical lens, the exposure time required for imaging must be extended, resulting in low energy utilization efficiency. US8023192B2 proposes a method of adding an injection-molded microlens array to the light-emitting diode array to focus the light. However, since the injection-molded microlens array is easily deformed due to shrinkage and warping, and alignment errors are easily generated during assembly, it will lead to degradation of imaging resolution. US8089077B2 proposes a method of directly forming a microlens structure array on the light-emitting diode array to focus the light. However, its procedure is relatively complicated, resulting in increased manufacturing difficulty and cost. US7582910B2 adopts a different light-emitting diode structure to form a photonic crystal structure of a two-dimensional diffraction grating on the surface of the light-emitting diode to control the light-emitting direction of the light-emitting diode. However, since this light-emitting diode containing a nano-sized photonic crystal structure is difficult to manufacture, the production cost is also high. The problems of low efficiency and high assembly difficulty encountered by the above related technologies are particularly obvious when using micro light emitting diodes such as micro-LED or mini-LED in high-resolution applications.

[0004] Therefore, it is urgent to provide an improved photosensitive imaging device and a preparation method thereof to eliminate or alleviate the above problems. Summary of the invention

[0005] In view of this, the present invention proposes a photosensitive imaging device and a method for preparing the photosensitive imaging device, which can be applied to a direct imaging photosensitive imaging device, which has the advantages of simple structure, low process difficulty, and low cost. It can limit the light-emitting angle of the light-emitting diode and effectively control the spot size projected on the output medium, thereby improving the resolution of the imaging.

[0006] To achieve the above-mentioned purpose, the photosensitive imaging device of the present invention comprises a substrate, a plurality of light-emitting diodes, a light-shielding layer, and may optionally include a flat layer and / or an anti-scratch layer. The plurality of light-emitting diodes are arranged on the substrate; the light-shielding layer is arranged on the plurality of light-emitting diodes and has a plurality of first openings, wherein the plurality of first openings respectively correspond to the light-emitting areas of the plurality of light-emitting diodes; the optional flat layer, if not removed after the plurality of first openings of the light-shielding layer are formed, is arranged between the plurality of light-emitting diodes and / or between the substrate and the light-shielding layer; the optional anti-scratch layer is arranged on the light-shielding layer. In addition to the aforementioned photosensitive imaging device, the present invention also proposes a method for preparing a photosensitive imaging device, for example, providing a substrate; transferring and fixing a plurality of light-emitting diodes on the substrate; selectively forming a flat layer between the plurality of light-emitting diodes and / or between the substrate and the light-shielding layer; forming a patternable light-shielding layer on the flat layer; patterning the light-shielding layer to form a plurality of first openings, wherein the plurality of first openings respectively correspond to the light-emitting areas of the plurality of light-emitting diodes; and selectively forming an anti-scratch layer on the light-shielding layer; patterning the anti-scratch layer to form a plurality of second openings; wherein the plurality of second openings respectively correspond to the plurality of first openings.

[0007] In one embodiment of the present invention, the material of the substrate may include glass, quartz, silicon wafer, sapphire, polycarbonate (PC), polyimide (PI), polypropylene (PP), polyethylene terephthalate (PET), and commonly used PCB materials (such as FR-4, BT, LCP, etc.) or a combination thereof, but the present invention is not limited thereto.

[0008] In one embodiment of the present invention, the thickness of the substrate may be between 100 and 1000 μm, for example, between 200 and 1000 μm, between 200 and 800 μm, between 200 and 700 μm, between 300 and 700 μm, between 300 and 500 μm, or about 400 μm, but the present invention is not limited thereto.

[0009] In one embodiment of the present invention, the material of the light shielding layer may include black photoresist, black ink, black resin, opaque metal or its oxide or non-metallic plating or coating, and a combination of plating or coating, but the present invention is not limited thereto. The opaque metal or its oxide includes chromium, nickel, silver, aluminum, titanium, molybdenum or its oxide, but the present invention is not limited thereto.

[0010] In one embodiment of the present invention, the light transmittance of the light shielding layer is not more than 5% to block the light emitted by the light emitting diode and limit its light emitting angle. If the light transmittance of the light shielding layer is lower, for example, the light transmittance is not more than 3%, or the light transmittance is not more than 1%, the light emitted by the light emitting diode can be blocked more effectively. In this embodiment, in order to achieve the requirement of low light transmittance, depending on the material used for the light shielding layer, its thickness can be between 0.05 and 30 μm, or between 0.4 and 20 μm, for example, between 0.1 and 10 μm, between 0.5 and 10 μm, between 0.5 and 8 μm, between 1 and 5 μm, between 1 and 3 μm, or between 1 and 2 μm, but the present invention is not limited thereto.

[0011] In one embodiment of the present invention, the color of the light shielding layer may be black to prevent light from being reflected onto the output medium through the surface of the light shielding layer, thereby causing degradation of imaging resolution.

[0012] In one embodiment of the present invention, the material of the planar layer may include polyimide (PI), polyacrylic acid, polyester, polyether, polystyrene, epoxy resin or copolymers thereof, interpenetrating polymer networks, mixtures or composite materials, but the present invention is not limited thereto.

[0013] In one embodiment of the present invention, the planar layer can be directly coated on the LED and cover the surface of the LED. The thickness of the planar layer depends on the height of the LED. The thickness of the portion directly coated on the LED can be between 0 and 50 μm, or between 0 and 10 μm, such as between 0 and 40 μm, between 0 and 30 μm, between 0 and 20 μm, between 0 and 5 μm, between 10 and 40 μm, between 10 and 30 μm, between 10 and 20 μm, or about 20 μm, but the present invention is not limited thereto. In this embodiment, the planar layer can be made of a material with a light transmittance of 70%, 80%, or 90% or more, so that the light emitted by the LED can directly penetrate the planar layer and then project onto the output medium containing the photosensitive material through the first opening and the second opening (in the presence of the anti-scratch layer). In another embodiment of the present invention, the patternable flat layer uses an opaque black material to prevent light crosstalk between adjacent light emitting diodes, and a plurality of flat layer openings are formed on the flat layer through patterning, and the plurality of flat layer openings correspond to the light emitting areas of the plurality of light emitting diodes, the first opening, and the second opening (in the presence of an anti-scratch layer), respectively, so that the light emitted by the light emitting diode can be projected onto the output medium through the flat layer openings, and then through the first opening and the second opening (in the presence of an anti-scratch layer). In this embodiment, the material of the flat layer can be photosensitive or non-photosensitive. SU-8 photoresist is one of the particularly suitable photosensitive flat layers. When a photosensitive flat layer material is used, the plurality of openings can be formed by a lithography process, including image exposure, and then using solvent washing or etching to form the openings.

[0014] In one embodiment of the present invention, the plurality of first openings of the light shielding layer are formed by depositing or coating a photosensitive or non-photosensitive flat layer on a substrate having light emitting diodes, and the plurality of light emitting diodes are exposed by grinding away the redundant flat layer, and a patternable light shielding layer is formed thereon and patterned to form the plurality of first openings. According to this embodiment, the light shielding layer may directly contact the light emitting diodes, and the flat layer between the light emitting diodes may be removed together when the light shielding layer is patterned.

[0015] In one embodiment of the present invention, the size of the plurality of first openings of the light shielding layer is related to the specification of the imaging resolution on the output medium. For example, if the specification of the imaging resolution on the output medium is 500 DPI, the size of a single pixel at this resolution is approximately 50.8 μm×50.8 μm. Therefore, the size of the effective light spot projected on the output medium by the light emitted by a single light emitting diode through the corresponding first opening of the light shielding layer, the second opening (in the case of the presence of the anti-scratch layer) and the opening of the flat layer (in the case of the presence of the flat layer) must be consistent with the required pixel size to meet this resolution specification. Generally speaking, the light intensity at the center of the light spot is the highest, and the light intensity decreases as it moves toward the periphery of the light spot. The effective light spot refers to the range extending from the center of the light spot and above a specific light intensity. The light intensity within this range is sufficient to make the photosensitive material on the output medium produce an effective reaction, and the size of this effective light spot is related to the size of the first opening of the light shielding layer, the distance between the output medium and the light emitting diode, and the light emitting power of the light emitting diode. Under the conditions that the distance between the output medium and the light-emitting diode, and the light-emitting power of the light-emitting diode are fixed, low imaging resolution requires a larger first opening of the light-shielding layer. Conversely, high imaging resolution requires a smaller first opening of the light-shielding layer. In this embodiment, depending on the distance between the photosensitive material and the light-emitting diode and the light-emitting power of the light-emitting diode, any single side or diameter of the first opening of the light-shielding layer may be between 0.4 and 1 times the side length of the pixel imaged on the output medium, or between 0.6 and 0.8 times the side length of the pixel, but the present invention is not limited to this.

[0016] In one embodiment of the present invention, an anti-scratch layer may also be included, and a plurality of second openings may be formed in the anti-scratch layer through a patterning step, wherein the plurality of second openings correspond to the plurality of first openings respectively; if a flat layer exists and has flat layer openings, the plurality of second openings also correspond to the flat layer openings of the flat layer.

[0017] In one embodiment of the present invention, the material of the anti-scratch layer may include silicon dioxide, silicon nitride, silicon oxynitride, titanium dioxide, aluminum nitride, aluminum oxide, metal, alloy, or a coating film of their oxides and combinations thereof or a polymer coating film containing such components, but the present invention is not limited thereto.

[0018] In one embodiment of the present invention, the thickness of the anti-scratch layer may be between 0.05 and 10 μm, or between 0.1 and 5 μm, for example, between 0.3 and 10 μm, between 0.3 and 8 μm, between 0.5 and 8 μm, between 0.5 and 5 μm, between 0.5 and 3 μm, between 1 and 3 μm, or about 1 μm, but the present invention is not limited thereto.

[0019] In one embodiment of the present invention, after forming a light-shielding layer on the flat layer, a scratch-resistant layer may be formed on the light-shielding layer first, and then the light-shielding layer and the scratch-resistant layer may be patterned simultaneously to simultaneously form a plurality of first openings and a plurality of second openings corresponding to the light-emitting areas of a plurality of light-emitting diodes.

[0020] In one embodiment of the present invention, at least one reflective layer may be further included, which is disposed between the light shielding layer and the substrate. The purpose of adding the reflective layer is to improve the utilization rate of the light emitted by the light emitting diode.

[0021] In one embodiment of the present invention, a reflective layer may be added and disposed between the plurality of LEDs and the substrate. The reflective layer may be disposed on the surface of the LED facing the substrate, and its reflective surface may face the first opening of the light shielding layer, so that the light emitted by the LED toward the substrate is reused through reflection. In this embodiment, a second patterned reflective layer may be added and disposed between the light shielding layer and the plurality of LEDs, and its reflective surface may face the substrate, so that the light emitted by the portion of the LED covered by the light shielding layer is reflected to the reflective layer on the surface of the LED facing the substrate for a second reflection, which may further improve the light utilization efficiency.

[0022] In one embodiment of the present invention, a patterned reflective layer may be added and disposed on the surface of the substrate facing the LED, and its reflective surface may face the first opening of the light shielding layer, so that the light emitted from the LED toward the substrate is reused through reflection. In this embodiment, a second patterned reflective layer may be added and disposed between the light shielding layer and the plurality of LEDs, and its reflective surface may face the substrate, so that the light emitted from the portion of the LED covered by the light shielding layer is reflected to the reflective layer on the surface of the substrate facing the LED for a second reflection, which can further improve the light utilization efficiency.

[0023] In one embodiment of the present invention, the material of the reflective layer may include aluminum, silver, nickel, cobalt, palladium, platinum, gold, zinc, tin, antimony, lead, copper, copper-silver, nickel-silver, alloys thereof, or metal mixtures thereof, but the present invention is not limited thereto.

[0024] In one embodiment of the present invention, the thickness of the reflective layer may be between 0.01 and 10 μm, or 0.05 and 3 μm, for example, between 0.1 and 8 μm, between 0.1 and 5 μm, between 0.1 and 3 μm, between 0.1 and 2 μm, between 0.1 and 1 μm, between 0.1 and 0.5 μm, or about 0.2 μm, but the present invention is not limited thereto.

[0025] In one embodiment of the present invention, a lithography process or an etching process well known to those skilled in the art may be used to pattern the light shielding layer, the anti-scratch layer or the reflective layer; however, the present invention is not limited thereto.

[0026] The following detailed description with reference to the accompanying drawings will make other objects, advantages, and novel features of the present invention more apparent. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 A cross-sectional view showing a photosensitive imaging device according to Embodiment 1 of the present invention.

[0028] Figure 2 A cross-sectional view showing a photosensitive imaging device according to Embodiment 2 of the present invention.

[0029] Figure 3 A cross-sectional view showing a photosensitive imaging device according to Embodiment 3 of the present invention.

[0030] Figure 4 A cross-sectional view showing a photosensitive imaging device according to Embodiment 5 of the present invention.

[0031] Figure 5 A cross-sectional view showing a photosensitive imaging device according to Embodiment 6 of the present invention.

[0032] 6A to 6F A flow chart showing the preparation of the photosensitive imaging device of Example 2 of the present invention is shown.

[0033] 7A to 7E A flow chart showing the preparation of the photosensitive imaging device of Example 6 of the present invention is shown.

[0034] Figure 8 The light spot simulation illumination diagram of Example 1 of the present invention is shown.

[0035] Fig. 9 A light spot simulation illumination diagram of a comparative example is shown.

[0036] Fig.10 The light spot simulation illumination diagram of Example 2 of the present invention is shown.

[0037] Fig.11 The light spot simulation illumination distribution diagram along the direction of the line connecting the center points of the two pins of the light emitting diode (X direction) when the distance between the light emitting diode and the photosensitive material is 30 μm is shown for the comparative example, embodiment 1 and embodiment 2 of the present invention.

[0038] Fig.12 The light spot simulation illumination distribution diagram is shown in the vertical direction (Y direction) along the line connecting the center points of the two pins of the light emitting diode when the distance between the light emitting diode and the photosensitive material is 30 μm for the comparative example, embodiment 1 and embodiment 2 of the present invention.

[0039] Fig.13 The image under a microscope is shown when the light emitting diode of the photosensitive imaging device of Example 2 is lit.

[0040] [Description of Reference Numerals]

[0041] 1-Substrate

[0042] 2-Substrate wire

[0043] 3-LED pins

[0044] 4-LED

[0045] 5- Flat layer

[0046] 51-Flat layer opening

[0047] 6-Shading layer

[0048] 7- Anti-scratch layer

[0049] 10-Photosensitive imaging device

[0050] 20-Output medium

[0051] V-opening

[0052] V1-First opening

[0053] V2-Second opening

[0054] R1, R2 reflective layer

[0055] 10, 10', 10", 10'', 10"" - Photosensitive imaging device

[0056] A1 - original luminous area

[0057] A2- Reduced light emitting area DETAILED DESCRIPTION

[0058] The following provides different embodiments of the present invention. These embodiments are used to illustrate the technical content of the present invention, but are not used to limit the scope of the present invention. A feature of an embodiment can be applied to other embodiments through appropriate modification, replacement, combination, and separation.

[0059] It should be noted that, in this document, unless otherwise specified, “a” element is not limited to a single element, but may include one or more elements.

[0060] In addition, in this document, unless otherwise specified, ordinal numbers such as "first" and "second" are only used to distinguish multiple components with the same name, and do not indicate that there is a hierarchy, level, execution order, or process order between them. A "first" component and a "second" component may appear together in the same component, or appear in different components. The presence of a component with a larger ordinal number does not necessarily indicate the presence of another component with a smaller ordinal number.

[0061] In this document, unless otherwise specified, the so-called feature A "or" or "and / or" (and / or) feature B means that A exists alone, B exists alone, or A and B exist at the same time; the so-called feature A "and" (and) or "and" (and) or "and" (and) feature B means that A and B exist at the same time; the so-called "includes", "comprising", "has" and "containing" mean including but not limited to these.

[0062] In addition, in this article, the terms "upper", "lower", "left", "right", "front", "back", or "between" are only used to describe the relative positions between multiple elements, and can be extended to include translation, rotation or mirroring.

[0063] Furthermore, herein, unless specifically stated otherwise, “an element is on another element” or the like does not necessarily mean that the element contacts the other element.

[0064] In addition, in this article, unless otherwise specified, a numerical value may include a range of ±10% of the numerical value, especially a range of ±5% of the numerical value. Unless otherwise specified, a numerical range is composed of multiple sub-ranges defined by a lower endpoint, a lower quartile, a median, an upper quartile, and a higher endpoint.

[0065] In addition, in this document, the term “patterning” refers to using a lithography process well known to those skilled in the art, and the micro-printing process includes transfer printing and stamping printing, or an etching process.

[0066] In addition, in this article, the term "coating" refers to a coating method familiar to those skilled in the art, such as dip coating, roller coating, printing coating, rotary coating, blade coating, wire rod coating, slit coating, or other coating methods, but the present invention is not limited thereto.

[0067] In the present invention, the photosensitive imaging device is an optical printer that directly forms an image on an output medium containing a photosensitive material, and its composition generally includes a print head having an array of exposure elements. In the following embodiments of the present invention, the print head of the optical printer is used for description, and the remaining elements of the optical printer can use known elements and are omitted.

[0068] Example 1

[0069] Figure 1 A cross-sectional view showing a photosensitive imaging device according to Embodiment 1 of the present invention.

[0070] like Figure 1As shown, the photosensitive imaging device 10 of this embodiment includes a substrate 1, a plurality of light-emitting diodes 4, a flat layer 5, a light-shielding layer 6 and an anti-scratch layer 7. Among them, a plurality of substrate wires 2 are arranged on the substrate 1. A plurality of light-emitting diodes 4 are arranged on the substrate 1 and each has a light-emitting diode pin 3, and the plurality of light-emitting diodes 4 are electrically connected to the corresponding substrate wires 2 via the pins 3. The flat layer 5 covers the surface of the light-emitting diodes 4. The light-shielding layer 6 is arranged on the flat layer 5 and has a plurality of first openings V1, wherein the plurality of first openings V1 respectively correspond to the light-emitting areas of the plurality of light-emitting diodes 4. In addition, the anti-scratch layer 7 is arranged on the light-shielding layer 6 and has a plurality of second openings V2, and the plurality of second openings V2 respectively correspond to the plurality of first openings V1. In this embodiment, the flat layer 5 is made of a material with high light transmittance, preferably a material with a light transmittance of more than 70%. Using a material with a higher light transmittance, such as a light transmittance greater than 80%, or even a light transmittance greater than 90%, will have a better effect, so that the light emitted by the light emitting diode 4 can penetrate the flat layer 5, and then projected onto the output medium 20 through the first opening V1 and the second opening V2. Part of the light emitted by the light emitting diode 4 is blocked by the light shielding layer 6 and cannot penetrate, thereby limiting the light emitting area and angle of the light emitting diode 4, and effectively controlling the spot size projected on the output medium 20, thereby improving the resolution of the imaging.

[0071] In this embodiment, the material of the substrate 1 is glass and its thickness is about 400μm, the material of the substrate wire 2 is copper, the light-emitting diode pin 3 is a gold-coated bump, the light-emitting diode 4 is a micro-LED flip-chip chip with a size of about 100μm×60μm×5μm, the material of the flat layer 5 is polyimide (PI) with good light transmittance and its thickness is about 15μm, the material of the shading layer 6 is black photoresist and its thickness is about 1μm, and the material of the anti-scratch layer 7 is silicon dioxide and its thickness is about 1μm.

[0072] Example 2

[0073] Figure 2 A cross-sectional view showing a photosensitive imaging device according to Embodiment 2 of the present invention.

[0074] like Figure 2As shown, the photosensitive imaging device 10' of this embodiment is similar to the photosensitive imaging device 10 of embodiment 1, except that this embodiment further includes a patterned reflective layer R1 disposed between the plurality of light-emitting diodes 4 and the substrate 1, which reflects the light emitted from the light-emitting diodes 2 to the bottom direction back to the direction of the output medium 20, thereby enhancing the illumination projected on the surface of the output medium 20. In this embodiment, the material of the reflective layer R1 is copper and its thickness is about 0.1 μm. The rest of the photosensitive imaging device 10' of this embodiment 2 is the same as the photosensitive imaging device 10 of embodiment 1, and thus will not be described in detail here. In addition, in the embodiment, the patterned reflective layer R1 is disposed on the surface of the light-emitting diode 4 facing the substrate 1, and its reflective surface faces the first opening V1; in another embodiment of the present invention, the patterned reflective layer R1 can be disposed on the surface of the substrate 1 facing the plurality of light-emitting diodes 4, and its reflective surface also faces the first opening V1, and when the reflective layer R1 and the substrate wire 2 are made of the same material, the reflective layer R1 and the substrate wire 2 can be formed in the same step. In this embodiment, the material copper of the reflective layer R1 is a conductive metal, so the reflective layer R1 cannot contact the pin 3 of the light-emitting diode 4 or the substrate wire 2 to avoid a short circuit. In another embodiment, the reflective layer R1 is an insulating material, so the reflective layer R1 can contact the pin 3 of the light-emitting diode 4 or the substrate wire 2.

[0075] Example 3

[0076] Figure 3 A cross-sectional view showing a photosensitive imaging device according to Embodiment 3 of the present invention.

[0077] like Figure 3 As shown, the photosensitive imaging device 10" of this embodiment is similar to the photosensitive imaging device 10' of embodiment 2, but the difference is that this embodiment has two patterned reflective layers. In addition to the reflective layer R1, a reflective layer R2 is added, which is arranged between the light shielding layer 6 and the plurality of light emitting diodes 4, and its reflective surface faces the substrate 1. Therefore, part of the light emitted by the plurality of light emitting diodes 4 can be reflected by the reflective layer R2, and then reflected by the reflective layer R1 before being reused. Therefore, the utilization rate of the light emitted by the plurality of light emitting diodes 4 can be further improved than that of embodiment 2.

[0078] Example 4

[0079] The photosensitive imaging device of this embodiment is similar to the photosensitive imaging device 10 ′ of Embodiment 2, except that the material of the anti-scratch layer of this embodiment is silicon nitride.

[0080] Example 5

[0081] Figure 4 A cross-sectional view showing a photosensitive imaging device according to Embodiment 5 of the present invention.

[0082] like Figure 4 As shown, the photosensitive imaging device 10'' of this embodiment is similar to the photosensitive imaging device 10' of Embodiment 2, except that the flat layer 5 of this embodiment is patternable and uses a material with low light transmittance. A flat layer opening 51 can be formed in the flat layer 5 through patterning, so that the light emitted by the plurality of light emitting diodes 4 can pass through the flat layer opening 51, and then through the first opening V1 and the second opening V2, and be projected onto the output medium 20. The flat layer 5 of this embodiment is black.

[0083] Example 6

[0084] Figure 5 A cross-sectional view showing a photosensitive imaging device according to Embodiment 6 of the present invention.

[0085] like Figure 5 As shown, the photosensitive imaging device 10"" of this embodiment includes a substrate 1, a plurality of light-emitting diodes 4, a flat layer 5, a light-shielding layer 6, and the plurality of light-emitting diodes 4 also have a reflective layer R1. Among them, a plurality of substrate wires 2 are arranged on the substrate 1. The plurality of light-emitting diodes 4 are arranged on the substrate 1 and each has a light-emitting diode pin 3, so that the light-emitting diode pins 3 of the plurality of light-emitting diodes 4 can be electrically connected to the corresponding substrate wires 2 respectively. The flat layer 5 is arranged between the substrate 1 and the light-shielding layer 6, and after grinding, the surface of the flat layer 5 is flush with the surface of the plurality of light-emitting diodes 4, so that the surfaces of the plurality of light-emitting diodes 4 are exposed. The light-shielding layer 6 is arranged on the plurality of light-emitting diodes 4 and directly contacts the light-emitting diodes 4, and the light-shielding layer 6 has a plurality of first openings V1, wherein the plurality of first openings V1 respectively correspond to the light-emitting areas of the plurality of light-emitting diodes 4. In this embodiment, a material with good wear resistance can be used as the light-shielding layer 6, so that an anti-scratch layer may no longer be required.

[0086] Method for preparing a photosensitive imaging device:

[0087] 6A to 6F A flow chart showing the preparation of the photosensitive imaging device of Example 2 of the present invention is shown.

[0088] In this embodiment, the method for preparing the photosensitive imaging device is based on 6A to 6F The steps are completed in sequence, and the steps are as follows.

[0089] like Fig. 6A As shown, this step is to transfer and fix multiple light-emitting diodes 4 to the substrate 1, wherein multiple substrate wires 2 are arranged on the substrate 1, and a reflective layer R1 is formed on the multiple light-emitting diodes 4, and the light-emitting diode pins 3 of the multiple light-emitting diodes 4 are electrically connected to the corresponding substrate wires 2, so that the reflective layer R1 is formed between the multiple light-emitting diodes 4 and the substrate 1.

[0090] like Figure 6BAs shown, this step is to form a flat layer 5 on the plurality of light emitting diodes 4. Here, the flat layer 5 is coated on the plurality of light emitting diodes 4. In this embodiment, the flat layer 5 can cover the surfaces of the plurality of light emitting diodes 4.

[0091] like Figure 6C As shown, this step is to form a light shielding layer 6 on the flat layer 5 . Here, the light shielding layer 6 is coated on the flat layer 5 .

[0092] like Fig.6D As shown, this step is to pattern the light shielding layer 6 to form a plurality of first openings V1, wherein the plurality of first openings V1 respectively correspond to the light emitting areas of the plurality of light emitting diodes 4. Here, the plurality of first openings V1 may be formed by using a lithography process.

[0093] like Fig. 6E As shown, this step is to form an anti-scratch layer 7 on the light shielding layer 6. Here, the anti-scratch layer 7 is deposited on the light shielding layer 6 by chemical vapor deposition (CVD).

[0094] like Fig. 6F As shown, this step is to pattern the anti-scratch layer 7 to form a plurality of second openings V2, wherein the plurality of second openings V2 respectively correspond to the plurality of first openings V1 to form openings V. Here, the plurality of second openings V2 may be formed by using a lithography process or a dry etching method.

[0095] 7A to 7E A flow chart showing the preparation of the photosensitive imaging device of Example 6 of the present invention is shown.

[0096] In this embodiment, the method for preparing the photosensitive imaging device is based on 7A to 7E The steps are completed in sequence, and the steps are as follows.

[0097] like Fig. 7A As shown, this step is to transfer and fix multiple light-emitting diodes 4 to the substrate 1, wherein multiple substrate wires 2 are arranged on the substrate 1, and a reflective layer R1 is formed on the multiple light-emitting diodes 4, and the light-emitting diode pins 3 of the multiple light-emitting diodes 4 are electrically connected to the corresponding substrate wires 2, so that the reflective layer R1 is formed between the multiple light-emitting diodes 4 and the substrate 1.

[0098] like Figure 7B As shown, this step is to form a flat layer 5 on the plurality of light emitting diodes 4 . Here, the flat layer 5 is coated on the plurality of light emitting diodes 4 and covers the surfaces of the plurality of light emitting diodes 4 .

[0099] like Figure 7C As shown, in this step, the planar layer 5 is ground until the surfaces of the plurality of light emitting diodes 4 are exposed.

[0100] like Fig.7DAs shown, this step is to form a light shielding layer 6 on the plane formed by the planar layer 5 and the plurality of light emitting diodes 4 .

[0101] like Fig. 7E As shown, this step is to pattern the light shielding layer 6 to form a plurality of first openings V1, wherein the plurality of first openings V1 respectively correspond to the light emitting areas of the plurality of light emitting diodes 4. Here, a lithography process may be used to form the plurality of openings V1.

[0102] Comparative Example

[0103] The comparative example is similar to the photosensitive imaging device 10' of Example 2, except that the bottom of the light emitting diode is coated with an absorption layer instead of a reflection layer. The preparation method of the photosensitive imaging device of the comparative example is similar to that of the photosensitive imaging device 10' of Example 2, so it will not be repeated here.

[0104] Light spot simulation

[0105] Software used for light spot simulation: ASAP optical simulation software.

[0106] Light spot simulation conditions: the size of the light-emitting diode 4 is set to 100μm×60μm×5μm; the thickness of the light-shielding layer 6 is set to 1.49μm; the size of the first opening V1 and the second opening V2 is set to 40μm×40μm; the wavelength of the light emitted by the light-emitting diode 4 is set to 527nm.

[0107] Figure 8 The light spot simulation illumination diagram of Example 1 of the present invention is shown.

[0108] Fig. 9 A light spot simulation illumination diagram of a comparative example is shown.

[0109] Fig.10 The light spot simulation illumination diagram of Example 2 of the present invention is shown.

[0110] Fig.11 The light spot simulation illumination distribution diagram along the direction of the line connecting the center points of the two pins of the light emitting diode (X direction) when the distance between the light emitting diode and the photosensitive material is 30 μm is shown for the comparative example, embodiment 1 and embodiment 2 of the present invention.

[0111] Fig.12 The light spot simulation illumination distribution diagram is shown in the vertical direction (Y direction) along the line connecting the center points of the two pins of the light emitting diode when the distance between the light emitting diode and the photosensitive material is 30 μm for the comparative example, embodiment 1 and embodiment 2 of the present invention.

[0112] Figure 8 This is a light spot illumination simulation diagram of Example 1, refer to Fig.11 and Fig.12It can be found that Example 1 can indeed project a light emitting diode with a light emitting area of ​​100 μm×60 μm onto a photosensitive material at a distance of 30 μm, and the illumination is reduced to a spot of 50 μm×50 μm within the range of 5% of the peak intensity. Fig.11 It shows that there is uneven illumination in the X direction. Fig. 9 To simulate the illumination of the light spot of the bottom absorption layer of the light-emitting diode, refer to Fig.11 and Fig.12 It can be found that plating an absorption layer on the bottom of the light-emitting diode can improve the uneven illumination in the X direction, but the overall illumination will be reduced. Fig.10 For the light spot illumination simulation of Example 2, refer to Fig.11 and Fig.12 It can be found that the illumination of the photosensitive imaging device of Example 2 is the most uniform and has the best intensity. Therefore, it can be seen that Example 1 and Example 2 of the present invention can indeed reduce the light spot projected on the surface of the output medium, and Example 2 can also effectively solve the problem of uneven illumination by adding a reflective layer to the photosensitive imaging device. The reflective layer can reflect and utilize the light from the bottom of the light-emitting diode, enhance the illumination of the surface of the photosensitive material, and further improve the resolution of the imaging.

[0113] Fig.13 The light-emitting diode of the photosensitive imaging device of Example 2 is lit up to form an image under a microscope, wherein the original light-emitting area A1 of the light-emitting diode (i.e., the light-emitting area of ​​the light-emitting diode 4) is 100 μm×60 qm, and the reduced light-emitting area A2 (i.e., the light-emitting area after the light emitted by the light-emitting diode 4 passes through the first opening V1 and the second opening V2) is about 40 qm×40 μm. The application condition of the photosensitive imaging device of Example 2 is that the photosensitive material is closely attached to the surface of the photosensitive imaging device. When the distance between the photosensitive material and the light-emitting diode is closer, the size of the light spot projected on the surface of the photosensitive material is closer to the size of the reduced light-emitting range, so the light spot can be effectively reduced to improve the resolution of the imaging.

[0114] Scratch resistance test

[0115] Scratch resistance test steps

[0116] First, attach the photosensitive material to the wool felt of the eraser testing machine; then add a load of 55g to the test rod and rub it at a speed of 2.54mm / second; the test distance is 90000mm; after the test, the base material must not be exposed and the light-emitting diode function must be normal.

[0117] Scratch resistance test results

[0118] Table 1

[0119]

[0120] It can be seen from Table 1 that both Example 2 and Example 3 have excellent anti-scratch performance, and Example 2 has a better wear resistance.

[0121] In summary, it can be found that through the provision of a shading layer and a reflective layer, the photosensitive imaging device of the present invention can limit the light-emitting angle of the light-emitting diode and effectively control the size of the light spot projected on the output medium containing the photosensitive material, thereby improving the imaging resolution and improving the uniformity of light, and has the advantages of simple structure, low process difficulty, and low cost.

[0122] Although the present invention has been described through a number of embodiments, it should be understood that many other possible modifications and variations may be made without departing from the spirit and scope of the present invention.

Claims

1. A photosensitive imaging device for directly imaging on an output medium, comprising: a substrate; A plurality of light emitting diodes are disposed on the substrate; A light shielding layer is disposed on the plurality of light emitting diodes and has a plurality of first openings, wherein the plurality of first openings respectively correspond to the light emitting areas of the plurality of light emitting diodes.

2. A photosensitive imaging device as described in claim 1, wherein the material of the light-shielding layer includes black photoresist, black ink, black resin, opaque metal or non-metallic plating or coating containing chromium, nickel, silver, aluminum, titanium, molybdenum or their oxides, and a combination of plating or coating.

3. The photosensitive imaging device as claimed in claim 1, wherein the light transmittance of the light shielding layer is not greater than 5%.

4. The photosensitive imaging device as claimed in claim 1, wherein the light transmittance of the light shielding layer is not greater than 3%. 5 . The photosensitive imaging device as claimed in claim 1 , wherein the light transmittance of the light shielding layer is not greater than 1%. 6 . The photosensitive imaging device as claimed in claim 1 , wherein the thickness of the light shielding layer is between 0.05 μm and 30 μm. 7 . The photosensitive imaging device as claimed in claim 1 , wherein the thickness of the light shielding layer is between 0.4 μm and 20 μm.

8. The photosensitive imaging device as claimed in claim 1, wherein the color of the light shielding layer is black.

9. The photosensitive imaging device as claimed in claim 1, wherein any single side or diameter of the first opening is between 0.4 and 1 times the side length of a pixel imaged on an output medium.

10. The photosensitive imaging device as claimed in claim 1, wherein any single side or diameter of the first opening is between 0.6 and 0.8 times the side length of a pixel imaged on an output medium.

11. The photosensitive imaging device as claimed in claim 1, further comprising a planar layer disposed between the plurality of light emitting diodes. 12 . The photosensitive imaging device as claimed in claim 1 , further comprising a planar layer disposed between the substrate and the light shielding layer.

13. The photosensitive imaging device as claimed in claim 11 or 12, wherein the material of the planar layer comprises polyimide (PI), polyacrylic acid, polyester, polyether, polystyrene, epoxy resin or copolymers thereof, interpenetrating polymer networks, mixtures or composite materials.

14. The photosensitive imaging device as claimed in claim 11 or 12, wherein at least one surface of the light emitting diode is covered by the planar layer.

15. The photosensitive imaging device as claimed in claim 14, wherein the light transmittance of the planar layer is greater than 70%.

16. The photosensitive imaging device as claimed in claim 14, wherein the light transmittance of the planar layer is greater than 80%.

17. The photosensitive imaging device as claimed in claim 14, wherein the light transmittance of the planar layer is greater than 90%. 18 . The photosensitive imaging device as claimed in claim 14 , wherein a thickness of a portion of the planar layer on the plurality of light emitting diodes is between 0 and 50 μm.

19. The photosensitive imaging device as claimed in claim 14, wherein a thickness of a portion of the planar layer on the plurality of light emitting diodes is between 0 and 10 μm. 20 . The photosensitive imaging device as claimed in claim 14 , wherein the planar layer has a plurality of planar layer openings, and the plurality of planar layer openings respectively correspond to the light emitting areas of the plurality of light emitting diodes and the plurality of first openings of the light shielding layer.

21. The photosensitive imaging device of claim 20, wherein the color of the planar layer is black.

22. The photosensitive imaging device as claimed in claim 1, further comprising an anti-scratch layer disposed on the light shielding layer.

23. The photosensitive imaging device as claimed in claim 22, wherein the anti-scratch layer comprises a plurality of second openings, and the plurality of second openings respectively correspond to the plurality of first openings.

24. The photosensitive imaging device as claimed in claim 22, wherein the material of the anti-scratch layer comprises silicon dioxide, silicon nitride, silicon oxynitride, titanium dioxide, aluminum nitride, aluminum oxide, metal, alloy, or a coating film of their oxides and combinations thereof, or a polymer coating film containing such components.

25. The photosensitive imaging device as claimed in claim 22, wherein the anti-scratch layer has a thickness between 0.05 and 10 μm.

26. The photosensitive imaging device as claimed in claim 22, wherein the anti-scratch layer has a thickness between 0.1 and 5 μm.

27. The photosensitive imaging device as claimed in claim 1, further comprising at least one reflective layer disposed between the light shielding layer and the substrate.

28. The photosensitive imaging device of claim 27, wherein the material of the reflective layer comprises aluminum, silver, nickel, cobalt, palladium, platinum, gold, zinc, tin, antimony, lead, copper, copper-silver, nickel-silver, alloys thereof, or metal mixtures thereof.

29. The photosensitive imaging device as claimed in claim 27, wherein the thickness of the reflective layer is between 0.01 and 10 μm.

30. The photosensitive imaging device as claimed in claim 27, wherein the thickness of the reflective layer is between 0.05 and 3 μm. 31 . The photosensitive imaging device as claimed in claim 27 , wherein the reflective layer is disposed between the plurality of light emitting diodes and the substrate, and a reflective surface of the reflective layer faces the first opening.

32. The photosensitive imaging device as claimed in claim 31, wherein the reflective layer is disposed on a surface of the plurality of light emitting diodes facing the substrate.

33. The photosensitive imaging device as claimed in claim 31, wherein the reflective layer is disposed on a surface of the substrate facing the plurality of light emitting diodes.

34. The photosensitive imaging device as claimed in claim 27, wherein the reflective layer is disposed between the light shielding layer and the plurality of light emitting diodes, and a reflective surface of the reflective layer faces the substrate.

35. A method for preparing a photosensitive imaging device for direct imaging on an output medium, comprising: providing a substrate; Transferring and fixing a plurality of light emitting diodes on the substrate; forming a light shielding layer on the plurality of light emitting diodes; The light shielding layer is patterned to form a plurality of first openings, wherein the plurality of first openings respectively correspond to the light emitting areas of the plurality of light emitting diodes.

36. A method for preparing a photosensitive imaging device as described in claim 35, wherein the material of the light-shielding layer includes black photoresist, black ink, black resin, an opaque metal or non-metallic plating or coating containing chromium, nickel, silver, aluminum, titanium, molybdenum or their oxides, and a combination of plating or coatings.

37. The method for preparing a photosensitive imaging device as claimed in claim 35, wherein the light transmittance of the light shielding layer is not greater than 5%.

38. The method for preparing a photosensitive imaging device as claimed in claim 35, wherein the light transmittance of the light shielding layer is not greater than 3%.

39. The method for preparing a photosensitive imaging device as claimed in claim 35, wherein the light transmittance of the light shielding layer is not greater than 1%.

40. The method for preparing a photosensitive imaging device as claimed in claim 35, wherein the thickness of the light shielding layer is between 0.05 and 30 μm.

41. The method for preparing a photosensitive imaging device as claimed in claim 35, wherein the thickness of the light shielding layer is between 0.4 and 20 μm.

42. The method for preparing a photosensitive imaging device as claimed in claim 35, wherein the color of the light shielding layer is black.

43. The method for preparing a photosensitive imaging device as described in claim 35, wherein any single side or diameter of the first opening is between 0.4 and 1 times the side length of a pixel imaged on an output medium.

44. The method for preparing a photosensitive imaging device as described in claim 35, wherein any single side or diameter of the first opening is between 0.6 and 0.8 times the side length of a pixel imaged on an output medium.

45. The method for preparing a photosensitive imaging device as claimed in claim 35, before forming the light shielding layer, further comprising the step of forming a planar layer, wherein the planar layer is formed between the plurality of light emitting diodes.

46. ​​The method for preparing a photosensitive imaging device as described in claim 35, before forming the light-shielding layer, further comprising the step of forming a planar layer, wherein the planar layer is formed between the substrate and the light-shielding layer.

47. The method for preparing a photosensitive imaging device as described in claim 45 or 46, wherein the material of the planar layer comprises polyimide (PI), polyacrylic acid, polyester, polyether, polystyrene, epoxy resin or its copolymer, interpenetrating polymer network, mixture or composite material.

48. The method for preparing a photosensitive imaging device as claimed in claim 45 or 46, wherein at least one surface of the light emitting diode is covered by the planar layer.

49. The method for preparing a photosensitive imaging device as claimed in claim 48, wherein the light transmittance of the planar layer is greater than 70%.

50. The method for preparing a photosensitive imaging device as claimed in claim 48, wherein the light transmittance of the planar layer is greater than 80%.

51. The method for preparing a photosensitive imaging device as claimed in claim 48, wherein the light transmittance of the planar layer is greater than 90%.

52. The method for preparing a photosensitive imaging device as claimed in claim 48, wherein a thickness of a portion of the planar layer on the plurality of light emitting diodes is between 0 and 50 μm.

53. The method for preparing a photosensitive imaging device as claimed in claim 48, wherein a thickness of a portion of the planar layer on the plurality of light emitting diodes is between 0 and 10 μm.

54. The method for preparing a photosensitive imaging device as described in claim 48, wherein the planar layer has a plurality of openings, and the plurality of openings respectively correspond to the light-emitting areas of the plurality of light-emitting diodes and the plurality of first openings of the light-shielding layer.

55. The method for preparing a photosensitive imaging device according to claim 54, wherein the color of the planar layer is black.

56. The method for preparing a photosensitive imaging device as described in claim 35, after forming the light-shielding layer, further comprising the step of forming an anti-scratch layer on the light-shielding layer.

57. The method for preparing a photosensitive imaging device as claimed in claim 56, further comprising the step of patterning the anti-scratch layer to form a plurality of second openings, wherein the plurality of second openings respectively correspond to the plurality of first openings.

58. A method for preparing a photosensitive imaging device as described in claim 56, wherein the material of the scratch-resistant layer includes silicon dioxide, silicon nitride, silicon oxynitride, titanium dioxide, aluminum nitride, aluminum oxide, metal, alloy, or a coating film of their oxides and combinations thereof, or a polymer coating film containing the components.

59. The method for preparing a photosensitive imaging device as claimed in claim 56, wherein the anti-scratch layer has a thickness between 0.05 and 10 μm.

60. The method for preparing a photosensitive imaging device as claimed in claim 56, wherein the anti-scratch layer has a thickness between 0.1 and 5 μm.

61. The method for preparing a photosensitive imaging device as claimed in claim 35, further comprising the step of forming at least one reflective layer between the light shielding layer and the substrate.

62. The method for preparing a photosensitive imaging device as described in claim 61, wherein the material of the reflective layer comprises aluminum, silver, nickel, cobalt, palladium, platinum, gold, zinc, tin, antimony, lead, copper, copper-silver, nickel-silver, alloys thereof, or metal mixtures thereof.

63. The method for preparing a photosensitive imaging device as claimed in claim 61, wherein the thickness of the reflective layer is between 0.01 and 10 μm.

64. The method for preparing a photosensitive imaging device as claimed in claim 61, wherein the thickness of the reflective layer is between 0.05 and 3 μm.

65. The method for preparing a photosensitive imaging device as described in claim 61, before the step of transferring and fixing the multiple light-emitting diodes on the substrate, also includes a step of forming the reflective layer between the multiple light-emitting diodes and the substrate, and the reflective surface of the reflective layer faces the first opening.

66. The method for preparing a photosensitive imaging device as claimed in claim 65, wherein the reflective layer is disposed on a surface of the plurality of light emitting diodes facing the substrate.

67. The method for preparing a photosensitive imaging device as claimed in claim 65, wherein the reflective layer is disposed on a surface of the substrate facing the plurality of light emitting diodes.

68. The method for preparing a photosensitive imaging device as described in claim 61, before the step of forming the light-shielding layer, further includes the step of forming the reflective layer between the light-shielding layer and the plurality of light-emitting diodes, and the reflective surface of the reflective layer faces the substrate.

Images