Light-emitting diode (LED) modules

Abstract

Light-emitting diode (LED) module, comprising: a substrate (110) containing a top surface; an LED package (200; 200') containing a light-emitting region (EL) and mounted on top of the substrate (110); a light sensor (300) containing a light receiving area (RL) and mounted on the top side of the substrate (110) horizontally next to the LED package (200; 200'); and a lens (150L; 150LC) aligned vertically above the light-emitting area (EL) of the LED package (200; 200') and at least partially overlapping the light-receiving area (RL) of the light sensor (300), wherein the lens (150L; 150LC) is a Fresnel lens, and wherein a central axis of the Fresnel lens (150L; 150LC) is aligned with a geometric center of the light-emitting region (EL) of the LED package (200; 200').

Description

BACKGROUND

[0001] Exemplary embodiments of the present inventive concept relate to light-emitting diode (LED) modules equipped with a flash LED and a light sensor, and to electronic devices incorporating the same.

[0002] Flash bulbs have long been used in conjunction with cameras to illuminate a subject being photographed in low-light conditions. These bulbs have largely been replaced by light-emitting diodes (LEDs) (referred to here as "flash LEDs") in modern digital camera devices, such as those built into mobile phones. Additionally and separately, modern digital camera devices may also be equipped with an ambient light sensor, which is used to calibrate camera parameters to improve the quality of an image captured by the camera.

[0003] Meanwhile, industry demands continue to drive the miniaturization of components used in electronic devices. Such demands also apply to camera design, particularly in the case of cameras embedded in mobile products such as mobile phones. While integrating a flash LED and an ambient light sensor into a camera design offers photographic advantages, these components take up valuable space in the limited available space for camera components.

[0004] US 2014 / 0 361 200 A1 discloses an optoelectronic module comprising a substrate, at least one emission part mounted on the substrate, at least one detection part mounted on the substrate, at least one optical part comprising at least one passive optical component, and at least one spacer part arranged between the substrate and the optical part.

[0005] US 2016 / 0011111 A1 discloses compact systems, devices, and methods for detecting changes in luminescence due to environmental influences on a luminescent material. Such systems, devices, and methods can be implemented in a compact device, e.g., an integrated circuit package, that can be incorporated into or attached to a device such as a smartphone, watch, flashlight, vehicle, etc. The described systems, devices, and methods are useful for detecting luminescence as well as changes in luminescence indicative of environmental influences, such as the presence and concentration of a gas or chemical, ambient temperature, pressure, light, etc., in a region surrounding a luminescent material contained in a compact device. SUMMARY

[0006] Aspects of the present inventive concept are set out in the appended claims.

[0007] According to one aspect of the present inventive concept, a light-emitting diode (LED) module is provided, including a substrate, an LED package, a light sensor, and a lens. The LED package includes a light-emitting region and is mounted on a top surface of the substrate. The light sensor includes a light-receiving region and is mounted horizontally on the top surface of the substrate next to the LED package. The lens is aligned vertically above the light-emitting region of the LED package and at least partially overlaps the light-receiving region of the light sensor.

[0008] According to another aspect of the present inventive concept, a light-emitting diode (LED) module is provided, including a substrate, an LED package, an ambient light sensor, and a module cover. The LED package includes a light-emitting region and is mounted on a top surface of the substrate. The ambient light sensor includes a light-receiving region and is mounted on the top surface of the substrate horizontally adjacent to the LED package. The module cover is formed of light-transmitting material and extends over the substrate to define a top wall of the LED module, and a portion of the module cover includes a Fresnel lens aligned vertically above the LED package for the light-emitting region and at least partially overlapping the light-receiving region of the ambient light sensor. The LED package includes an LED chip and a wavelength conversion film disposed over the LED chip.The LED package further includes a reflective structure having vertical reflective sidewalls surrounding the LED chip and the wavelength conversion film to prevent light emission from side surfaces of the LED chip and the wavelength conversion film.

[0009] According to another aspect of the inventive concepts, a light-emitting diode (LED) module is provided that includes a substrate, an LED package, and a module cover. The LED package includes a light-emitting region and is mounted on top of the substrate. The module cover is formed of a transmissive material and extends above the substrate to define a top wall of the LED module, and a portion of the module cover includes a lens aligned over the light-emitting region of the LED package. An underside of at least the lens of the module cover is roughened to form a visual obstruction against viewing the LED package through the lens from outside the module cover.

[0010] According to yet another embodiment of the inventive concepts, an electronic device is provided that includes a camera lens, a light-emitting diode (LED) module, a lens, and an outer housing. The LED module includes an LED package and an ambient light sensor mounted horizontally side by side on a substrate. The lens is aligned over the LED package and at least partially overlaps the ambient light sensor, and the outer housing includes a light-transmitting region. The LED package operates to emit light through the lens and the light-transmitting region, and the ambient light sensor operates to sense light through the lens and the light-transmitting region.The light sensor is configured to receive ambient light to generate information regarding flicker, color, and / or brightness, and the electronic device is configured to correct a camera image or control the light output of the LED package based on the information. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The above and other aspects, features and advantages of the present inventive concept will be better understood from the following detailed description taken in conjunction with the accompanying drawings, in which: Fig. 1 is an exploded perspective diagram illustrating a flash LED module according to an example embodiment of the present inventive concept; Fig. Figure 2A is a cross-sectional diagram showing the flash LED module (in assembled state) shown in Fig. 1, along I1-I1' in Fig. 1 represents; Fig. 2B is a perspective diagram showing a module cover of the Fig. 1 represents the flash LED module; Fig. 3A and Fig. 3B are cross-sectional diagrams illustrating LED devices that may be employed in a flash LED module according to an exemplary embodiment of the present inventive concept; Fig. 4A and Fig. 4B are cross-sectional diagrams illustrating semiconductor LED chips that can be used in a flash LED module according to an exemplary embodiment of the present inventive concept; Fig. 5 is a cross-sectional view showing a light sensor usable in a flash LED module according to an exemplary embodiment of the present inventive concept taken along line II-II' in Fig. 6 represents; Fig. 6 is a plan diagram of the Fig. 5 shown light sensor; Fig. 7A is a diagram of the layout of a light receiving area of the Fig. 5 shown light sensor, and Fig. Figure 7B is a diagram of the light spectra emitted by the Fig. 7A shown light receiving area; Fig. 8 is an exploded perspective diagram illustrating a flash LED module according to an example embodiment of the present inventive concept; Fig. Figure 9A is a cross-sectional diagram showing the Fig. 8 shows the flash LED module (in assembled state); Fig. 9B is a perspective diagram showing a Fig. 8 shows the module cover of a flash LED module; Fig. 10 is a perspective diagram showing the Fig. 9A shows the flash LED module in combination with adjacent components; Fig. 11A and Fig. 11B are perspective diagrams illustrating a front and a back of a camera-embedded mobile device according to an example embodiment of the present inventive concept; and Fig. 12 is a cross-sectional diagram illustrating a flash LED module according to an exemplary embodiment of the present inventive concept. DETAILED DESCRIPTION

[0012] Hereinafter, embodiments of the present inventive concept will be described with reference to the accompanying drawings.

[0013] Throughout this specification, the relative positions of the components are described using terms such as "upper," "lower," "above," "below," "vertical," "horizontal," and the like. These terms are for descriptive purposes only and are intended to describe the relative positions of the components, assuming that the orientation of the overall device is the same as that shown in the drawings. However, the embodiments are not limited to the illustrated device orientations.

[0014] Fig. 1 is an exploded perspective diagram showing a flash LED module according to an example embodiment. Fig. Figure 2A is a cross-sectional diagram showing the Fig. 1 shows the flash LED module (an assembled state).

[0015] With reference to Fig. 1 and Fig. 2A, a flash LED module 100 in the example embodiment may include a substrate 110, an LED package 200, and a light sensor 300. As shown, the LED package 200 and the light sensor 300 may be disposed horizontally side by side on a top surface or surfaces of the substrate 110. The flash LED module 100 may further include a module cover 150 disposed over the substrate 110 to cover the LED package 200 and the light sensor 300. The module cover 150 may be formed from a light-transmitting material and may define a top wall of the flash LED module 100.

[0016] The substrate 110 may be embodied as a printed circuit board (PCB), a metal core PCB (MCPCB), a metal PCB (MPCB), a flexible PCB (FPCB), or the like, and the LED package 200 and the light sensor 300 may be electrically connected to one or more circuits of the substrate 110. In example embodiments, one or more additional devices 120 (e.g., a circuit protection Zener diode) may be mounted on the substrate 110. Furthermore, although the substrate 110 is illustrated in the figures as a single continuous layer, the inventive concepts are not limited in this manner. In other embodiments, the substrate 110 may be a multi-layer structure. Although the substrate 110 is illustrated as a continuous and planar surface, the inventive concepts are not limited in this manner.In other embodiments, the substrate 110 may have a non-planar top surface and / or include physically separate top surface portions (e.g., with a trench, step, or wall therebetween), and the LED package 200 and the light sensor 300 may be disposed on the same or different ones of these physically separate top surface portions. In other embodiments, the top surface portions on which the LED package 200 and the light sensor 300 are disposed, respectively, may not be coplanar. In other words, one of the LED package 200 and the light sensor 300 may be vertically elevated relative to the other.

[0017] The LED package 200 may contain one or more LED chips (not shown). It should be noted that the term "flash" in terms such as "flash LED module" has no particular structural significance beyond the LED chip(s) that may function as a camera's light flash. That is, it is understood that "flash" is a term that refers to the relative light-emitting capacity rather than the structure.

[0018] Side surfaces of the LED package 200 may be surrounded by vertical side walls of a reflective structure 260. A light-emitting region EL ( Fig. 2A) of the LED package 200 may be a top side of the LED package 200 surrounded by the reflective structure 260. The LED package 200 may include an LED chip and a wavelength conversion element configured to emit white light. A more detailed description of examples of the LED package 200 will be given later with reference to Fig. 3A and Fig. 3B given.

[0019] The light sensor 300 may have a light receiving area RL for receiving light and may be arranged horizontally adjacent to the LED package 200. The light receiving area RL may include a photodiode array. The light sensor 300 may be an ambient light sensor, in which case, the light receiving area RL receives ambient light. The light sensor 300 may detect other aspects of a sensed environment, such as infrared (IR) energy and flicker.

[0020] For example, when a camera captures an image in a dimly lit environment, the LED package 200 of the flash LED module 100 may be operated to emit a flash of light. Independently, the light sensor 300 may be operated to receive ambient light and provide corresponding information used to correct the image captured by the camera.

[0021] In the example embodiment, a vertical wall of the reflective structure 260 may be inserted between the LED package 200 and the light sensor 300 to prevent or obstruct the light emitted by the LED package 200 from reaching the light sensor 300 adjacent to the LED package 200. The reflective structure 260 may be formed from a resin material containing a reflective powder. For example, the resin material may contain silicone or an epoxy. The reflective powder may be a white ceramic powder or a metal powder. Examples of the white ceramic powder include at least one of TiO2, Al2O3, Nb2O5, or ZnO. Examples of the metal powder include Al or Ag.

[0022] The module cover 150 may cover the LED package 200 and the light sensor 300 and may include a lens 150L contained therein in a region overlapping the light-emitting region EL. As shown in the figures, in one embodiment, the lens 150L forms an integral part of the module cover 150, and the module cover 150 including the lens 150L may be a one-piece structure. The lens 150L may be vertically aligned over the light-emitting region EL of the LED package 200, and as illustrated in the drawings, an optical center axis LA of the lens 150L may be vertically aligned with a geometric center of the light-emitting region EL. In the example embodiment, the module cover 150 may have a flat rectangular shape in which the lens 150L is located and may be supported by sidewall structures 152, such as a post, that extends upwardly from a surface of the substrate 110.However, the structure and shape of the module cover 150 can be varied.

[0023] A sub-area 150L' ( Fig. 2B) of the lens 150L can be provided as a light incident region in which light emitted from the light-emitting region EL of the LED package 200 is incident on a bottom surface of the module cover 150. The lens 150L can be configured to evenly distribute the light incident from the light-emitting region EL over a wide angle. In example embodiments, the lens 150L can be configured as a Fresnel lens. For example, a field of view (FOV) of the lens 150L can be 100° or higher or 120° or higher. As indicated by the dashed circle in Fig. 1, a horizontal area of the lens 150L may be larger than an area of the light-emitting area EL of the LED package 200, so that the lens 150L completely overlaps the light-emitting area EL.

[0024] In addition, as in Fig. 1 and Fig. 2A, the horizontal surface of the lens 150L may be configured such that at least a portion of the light receiving area RL of the light sensor 300 is overlapped by the lens 150L. Accordingly, if a boundary line LB extends along the outer edge of the lens 150L in a direction perpendicular to the substrate 110, the boundary line LB may be disposed within the light receiving area RL.

[0025] Fig. 2A shows a gap d, which represents a horizontal distance between the light sensor 300 and the LED package 200. The gap d can be, for example, 300 µm or less (alternatively, 200 µm or less). The light receiving area RL of the light sensor 300 can receive incident light through the lens 150L. That is, in the arrangement of the present embodiment, the lens 150L can be aligned with an optically transmissive hole (herein referred to as a transmissive opening) in the housing of a device (e.g., a smartphone) containing the LED module 100. In this case, flash light emitted by the LED package 200 can be projected through the hole, and ambient light detected by the light sensor 300 can be received through the same transmissive hole in the housing of the device.

[0026] In this arrangement, the LED package 200 and the light sensor 300 arranged under the module cover 150 may be visually exposed through the module cover 150, which may be aesthetically undesirable. As shown in Fig. 2B, this can be prevented or mitigated by roughening an underside 150B of the module cover 150 to visually create a frost-like effect across the underside 150B, which acts as a visual obstruction to the view of the elements beneath the module cover 150. Furthermore, the degree of roughening can vary depending on a position on the underside 150B. For example, Fig. 2B illustrates the bottom surface region 150L' of the module cover 150, which forms a bottom surface of the lens 150L and a remaining bottom surface region 150P of the module cover 150. The bottom surface region 150L' may have a surface roughness R2 that differs from a surface roughness R1 of the remaining bottom surface region 150P. Since the roughening may reduce the amount of light transmitted through the module cover 150, in embodiments, the surface roughness R2 of the bottom surface region 150L' may be less than the surface roughness R1 of the remaining bottom surface region 150P. As examples, an arithmetic mean value (R2) of the surface roughness of the bottom surface region 150L' of the lens 150L of the module cover 150 may be in a range of 0.1 μm to 1.0 μm, and an arithmetic mean value of the surface roughness (R1) of the remaining bottom surface region 150P of the module cover 150 may be 0.8 μm or more.Here, the arithmetic mean of surface roughness is typically denoted by “Ra” and denotes the arithmetic mean of the absolute values of profile height deviations from a mean contour line along a length of the surface.

[0027] In example embodiments, the surface roughening may also or instead be applied to a top surface 150A of the module cover 150A. An example of this will be described later in connection with Fig. 8 described.

[0028] The module cover 150 can be molded from a translucent material, such as a translucent resin, and manufactured using a mold. In this case, the module cover 150 can be realized with the above-described surface roughness by forming serrations with an appropriate surface roughness in each region, along with an engraved structure corresponding to a Fresnel lens, on one surface of the mold.

[0029] Fig. 3A and Fig. 3B are cross-sectional diagrams illustrating two types of LED devices that can be used in a flash LED module according to an example embodiment. However, the inventive concepts are not limited to the examples of Fig. 3A and Fig. 3B limited.

[0030] With reference to Fig. 3A, an LED package 200 in the example embodiment may include a wiring substrate 210, an LED chip 250, and a wavelength conversion film 280. The wiring substrate 210 may include first and second wiring electrodes 212a and 212b. The LED chip 250 may be mounted on the wiring substrate 210 such that the first and second electrode pads 259a and 259b of a bottom surface of the LED chip are connected to the first and second wiring electrodes 212a and 212b of the wiring substrate 210, respectively. The wavelength conversion film 280 may be disposed on a top surface of the LED chip 250. The LED chip 250 and the wavelength conversion film 280 may be configured to emit white light.

[0031] As previously described, the LED package 200 in the example embodiment may be surrounded by a reflective structure 260. As in Fig. As shown in Figure 3A, the reflective structure 260 includes vertical sidewalls that may surround side surfaces of the LED chip 250 and side surfaces of the wavelength conversion film 280. The reflective structure 260 may prevent or minimize the light emitted by the LED package 200 from adversely affecting the operation of the adjacent light sensor 300.

[0032] The wiring substrate 210 may include an insulating resin and a ceramic substrate. The first and second wiring electrodes 212a and 212b may include a metal such as Au, Cu, Ag, and Al. The first and second electrode pads 259a and 259b of the LED chip 250 may be connected to the first and second wiring electrodes 212a and 212b by solder balls. Fig. The LED package 200 shown in Figure 3A may be configured as a chip-scale package, and a wiring structure may be formed directly on the first surface of the LED chip 250 using a wafer-level manufacturing process.

[0033] The wavelength conversion film 280 may include at least one type of wavelength conversion material for converting a portion of the light emitted by the LED chip 250 into light having a given wavelength different from a wavelength of the emitted light. The wavelength conversion film 280 may be configured as a resin layer on which the wavelength conversion material is dispersed or as a ceramic fluorescent film. For example, the wavelength conversion material may be at least one of a fluorescent material and a quantum dot.

[0034] For example, the LED package 200 can be configured to emit white light. In example embodiments, the LED chip 250 can emit blue light. For example, the LED chip 250 can emit light having a primary wavelength of 440 nm to 460 nm. The wavelength conversion material can include a fluorescent material or a quantum dot that converts a portion of the blue light to yellow light, or it can include multiple fluorescent materials or multiple quantum dots that convert a portion of the blue light to red and green light.

[0035] Fig. 3B illustrates an LED package 200' in another example embodiment. This embodiment is similar to the one shown in Fig. 3A, except that the LED package 200' additionally includes a light-transmitting film 290 having a low refractive index.

[0036] That is, the LED package 200' may further include a light-transmitting film 290 disposed on the wavelength-conversion film 280. In this case, a reflective structure 260' may be configured to further surround the light-transmitting film 290 together with the LED chip 250 and the wavelength-conversion film 280. In the example embodiment, the reflective structure 260' may be configured to have a height higher than a top surface of the wavelength-conversion film 280, thereby increasing the efficiency of light condensation onto the lens 150L (in Fig. 1). By incorporating the light-transmitting film 290 with a low refractive index, the efficiency of light extraction can be increased.

[0037] The flash LED packages 200 and 200' used in the example embodiments may have a flip-chip structure in which a surface on which the light-emitting region EL is provided may be configured to oppose a surface on which electrodes are formed. The flash LED packages 200 and 200' may include a reflective structure 260 surrounding at least the LED chip 250 and the wavelength conversion film 280 to easily condense the light emitted by the LED chip 250. In example embodiments, the LED package 200 may be configured as a compact chip-scale package.

[0038] The LED package 200 (and 200') can contain different types of LED chips in a variety of package structures. Fig. 4A and Fig. 4B are cross-sectional diagrams illustrating two examples of the LED chips.

[0039] With reference to Fig. 4A, an LED chip 250A may include a substrate 251 and a semiconductor stack structure S including a first conductivity type semiconductor layer 254, an active layer 255, and a second conductivity type semiconductor layer 256. A buffer layer 252 may be disposed between the substrate 251 and the first conductivity type semiconductor layer 254.

[0040] The substrate 251 may be configured as an insulating substrate, such as a sapphire substrate. However, an example embodiment thereof is not limited thereto. The substrate 251 may be configured as a conductive substrate or a semiconductor substrate that is not an insulating substrate. For example, the substrate 251 may be formed of SiC, Si, MgAl2O4, MgO, LiAlO2, LiGaO2, and GaN, except for sapphire. A serration C may be formed on a top surface of the substrate 251. The serrations C can improve the light extraction efficiency and the quality of a grown single crystal.

[0041] The buffer layer 252 can x Al y Ga 1-x-yN (0≤x≤1, 0≤y≤1). The buffer layer 252 can be formed of, for example, GaN, AlN, AlGaN, and InGaN. If desired, the buffer layer 252 can be formed by combining multiple layers, or it can include multiple layers in which part of the composition of the layers is gradually changed.

[0042] The semiconductor layer 254 of the first conductivity type may be formed of a nitride semiconductor corresponding to the n-type In x Al y Ga 1-x-y N (0≤x<1, 0≤y<1, 0≤x+y<1), and the n-type impurity may be Si. For example, the first conductivity type semiconductor layer 254 may include n-type GaN. The second conductivity type semiconductor layer 256 may be formed from a nitride semiconductor layer corresponding to the p-type In x Al y Ga 1-x-yN (0≤x<1, 0≤y<1, 0≤x+y<1), and the p-type impurity may be Mg. For example, the second conductivity type semiconductor layer 256 may have a single-layer structure, or the second conductivity type semiconductor layer 256 may include multiple layers having different compositions.

[0043] The active layer 255 may have a multiple quantum well MQW structure in which a quantum well layer and a quantum wall layer are alternately layered. For example, the quantum well layer and the quantum wall layer may be x Al y Ga 1-x-y N (0≤x≤1, 0≤y<1, 0≤x+y≤1) and have different compositions. In an example embodiment, the quantum well layer In x Ga 1-xN (0<x≤1) sein und die Quantenwand-Schicht kann GaN oder AlGaN sein. Die Dicken der Quantentopf-Schicht und der Quantenwand-Schicht können in einem Bereich von 1 nm bis 50 nm liegen. Die aktive Schicht 255 darf nicht auf eine Mehrfach-Quantentopfstruktur beschränkt sein und kann eine Einzel-Quantentopf-Struktur aufweisen.

[0044] The first and second electrode pads 259a and 259b may be disposed on a mesa-etched region of the first conductivity-type semiconductor layer 254 and the second conductivity-type semiconductor layer 256. The first electrode 259a may include elements such as Ag, Ni, Al, Cr, Rh, Pd, Ir, Ru, Mg, Zn, Pt, Au, and the like, but a material of the first electrode pad 259a is not limited thereto. The first electrode pad 259a may have a single layer or two or more layers. If desired, the second electrode surface 259b may be configured as a permeable electrode composed of a permeable conductive oxide or a permeable conductive nitride and may include graphene. The second electrode pad 259b may include at least one of the elements Al, Au, Cr, Ni, Ti, and Sn.

[0045] Fig. 4B is a cross-sectional diagram showing an example of another type of solid-state LED that may be employed in the example embodiments.

[0046] With reference to Fig. 4B, a semiconductor LED chip 250B may include a substrate 251 and a semiconductor stack structure S disposed on the substrate 251. The semiconductor stack structure S may include a buffer layer 252, a semiconductor layer 254 of the first conductivity type, an active layer 255, and a semiconductor layer 256 of the second conductivity type.

[0047] The semiconductor LED chip 250B may include first and second electrode structures E1 and E2 connected to the semiconductor layers 254 and 256 of the first and second conductivity types. The first electrode structure E1 may include a terminal electrode 258a, e.g., a conductive via, penetrating the semiconductor layer 256 of the second conductivity type and the active layer 255 and connected to the semiconductor layer 254 of the first conductivity type, and a first electrode pad 259a connected to the terminal electrode 258a. The terminal electrode 258a may be surrounded by an insulating portion 257 and electrically insulated from the active layer 255 and the semiconductor layer 256 of the second conductivity type. The terminal electrode 258a may be arranged in a region in which the semiconductor stack structure S is etched.The number, shape, spacing, and contact area of the connection electrode 258a with the first conductivity type semiconductor layer 254 can be appropriately configured to reduce contact resistance. The connection electrode 258a can be arranged on the semiconductor stack structure S to form a row and a column, thereby improving current flow. The second electrode structure E2 can include an ohmic contact layer 258b arranged on the second conductivity type semiconductor layer 256 and a second electrode pad 259b.

[0048] The terminal electrode 258a and the ohmic contact layer 258b may include a single layer or multiple layers of a conductive material having ohmic properties. For example, the terminal electrode 258a and the ohmic contact layer 258b may include materials such as Ag, Al, Ni, Cr, a transparent conductive oxide (TCO), and the like.

[0049] The first and second electrode pads 259a and 259b can be connected to the terminal electrode 258a and the ohmic contact layer 258b, respectively, and can function as an external terminal of the LED chip 250B. For example, the first and second electrode pads 259a and 259b can be formed from Au, Ag, Al, Ti, W, Cu, Sn, Ni, Pt, Cr, NiSn, TiW, or AuSn, or eutectic metals thereof. The first and second electrode structures E1 and E2 can be arranged to face in the same direction.

[0050] Fig. Figure 5 is a cross-sectional view (along the line II-II' in Fig. 6), which shows a light sensor usable in a flash LED module according to an example embodiment, and Fig. 6 is a plan diagram showing the Fig. 5 represents the light sensor shown.

[0051] With reference to Fig. 5 and Fig. 6, a light sensor 300 in the example embodiment may include a lead frame 312, a light sensor chip 350 disposed on the lead frame 312, and a transmissive resin layer 330 disposed on the lead frame 312 and encapsulating the light sensor chip 350. The light sensor chip 350 may include a plurality of terminals 355, and the plurality of terminals 355 may be connected to the lead frame 312 by a wire W.

[0052] As in Fig. As shown in Figure 6, the light sensor chip 350 may include a light receiving region RL located on a top surface adjacent to a side corner, and a peripheral circuit region PC located in the other region of the top surface. The light receiving region RL may include a photodiode array, and the peripheral circuit region PC may include a circuit device, such as a transistor.

[0053] Fig. 7A is a diagram showing the layout of a light receiving area RL of the Fig. 5 illustrated light sensor, and Fig. Figure 7B is a diagram illustrating a spectrum of light emitted by the Fig. 7A shown light receiving area.

[0054] As in Fig. As shown in Figure 7A, the light receiving region RL of the light sensor 300 may include a plurality of photodiode cells PD and may include a first region PA1 for detecting visible light, a second region PA2 for detecting flicker, and a third region PA3 for detecting infrared light. The first to third regions PA1 to PA3 of the light receiving region RL may detect light that meets the Fig. 7B shown spectra.

[0055] For example, a photodiode cell PD in the first region PA1 can detect red light R, green light G, and blue light B, as well as a broad band W and a clear band C. The photodiode cells in the second and third regions PA2 and PA3 can detect flicker (F) and infrared light (IR).

[0056] Fig. 8 is an exploded perspective diagram showing a flash LED module according to another example embodiment, and Fig. Figure 9A is a cross-sectional diagram showing the Fig. 8 shows the flash LED module (in assembled state).

[0057] With reference to Fig. 8 and Fig. 9A, a flash LED module 100A in the example embodiment may be similar to that shown in Fig. 1 and Fig. 2A, except for the position of the light sensor 300 relative to the lens and the structure of the module cover 150'. The elements in the example embodiment may, unless otherwise noted, be identical to those shown in Fig. 1 and Fig. 2A may be identical or similar to the elements of the flash LED module 100.

[0058] Similar to the above-mentioned example embodiment, a light sensor 300 in the present example embodiment may be disposed adjacent to an LED package 200, and a light receiving area RL may be disposed in an area adjacent to the LED package 200 on a top surface of the light sensor 300. In the present example embodiment, the lens 150L overlaps an entirety of the light receiving area RL of the light sensor 300.

[0059] That is, assuming that a boundary line LB extends at the outer edge of the lens 150L in a direction perpendicular to the substrate 110, the entire light receiving area RL can be arranged within the boundary line LB. In this arrangement, the light of the LED package 200 can be emitted outward, and the ambient light detected by the light sensor 300 can be received through a single transmissive hole LH aligned with the lens 150L. For example, the transmissive hole LH, which is provided as an optical opening, can be provided by a transmissive hole structure 410 arranged in a housing of a device containing a camera. For example, the transmissive hole structure 410 can include an opaque film forming a light-blocking layer BL in a region different from the transmissive hole LH on a surface (e.g., a bottom surface) of a transmissive body housing of a device, such as a smartphone.The transmissive body housing may be a glass substrate. In this case, in the exemplary embodiment, the light-receiving area of the light sensor may be configured to be located within the boundary line LB of the transmissive hole LH. In this case, the diameter of the transmissive hole may be larger than the diameter of the lens.

[0060] As described above, in the example embodiment, the light sensor 300 can be arranged so that the entire light receiving area RL can overlap the lens 150L, thereby efficiently receiving the ambient light through the lens 150L.

[0061] As in Fig. 9B, in the example embodiment, a bottom surface 150B of the module cover 150' may include a bottom surface portion 150L' of the lens 150L having a surface roughness R2 that is less than a surface roughness R1 of a remaining bottom surface portion 150P1 of the module cover 150'. As in the previous embodiment, a surface roughness R2 of the bottom surface portion 150L' of the lens 150L' may be 0.1 µm or higher and may be less than a surface roughness R1 of the bottom surface portion 150P1. For example, the surface roughness R2 of the bottom surface region 150L' of the lens 150L' may be in a range of 0.1 µm to 1.0 µm, and a surface roughness R1 of the other bottom surface region 150P1 of the module cover 150' may be 0.8 µm or higher.

[0062] The module cover 150' in the example embodiment may include a light incidence region 150R having a central concavity that focuses the light onto a portion of the opposite light-emitting region EL of the LED package 200. The central concavity of the light incidence region 150R may be a cylindrical shape, a cut-out conical shape, a spherical shape, or a combination thereof.

[0063] A bottom surface region 150L' of the lens 150L may include the concave light incident region 150R, and the surface roughness of the concave light incident region 150R may be in a range of 0.1 µm to 1.0 µm.

[0064] A top surface 150A of the module cover 150' can be processed in a similarly cloudy manner as the other bottom surface area 150P1 of the module cover 150'. As shown in Fig. As shown in Figure 8, the other top surface region 150P2 of the module cover 150', excluding the lens 150L, has a surface roughness R1 greater than a surface roughness R2. For example, the surface roughness R2 of the other top surface region 150P1 of the module cover 150' other than the lens 150L may be 0.8 μm or more.

[0065] The lens 150L may be configured to have an area larger than an area of the light-emitting region EL. The module cover 150' may have a portion 150E extending outside the substrate 110 so as not to overlap the substrate 110, and a portion of the lens 150L may be disposed in the extended portion 150E. The module cover 150' may have an area larger than an area of the substrate 110.

[0066] The module cover 150' may include a sidewall structure 152 that supports a plate portion and is mounted on the substrate 110. The sidewall structure 152 in the example embodiment may include two sidewall structures 152 arranged opposite each other at both corners and open in a direction in which the LED package 200 and the light sensor 300 are arranged. Since both side surfaces of the flash LED module 100A arranged in the arrangement direction are configured to be opened, the side surfaces can be provided as paths through which the heat emitted from the LED package 200 is dissipated.

[0067] As in Fig. As shown in Figure 8, an empty space may be present in the flash LED module 100A because, as shown in the cross-sectional diagram, no substrate is disposed under the extended portion 150E of a module cover 150'. When the flash LED module 100A is mounted on a mobile device including a camera, the flash LED module and the other components can be arranged in a condensed manner using the empty space. Fig. 10 is a perspective diagram illustrating a combined state in which the Fig. 9A, the flash LED module 100A is combined with adjacent components.

[0068] With reference to Fig. 10, a camera lens module 450 may be arranged adjacent to an LED package 200. For example, the other module may be configured as a camera lens module 450 having a drum.

[0069] A housing of the camera lens module 450 may have an upper end portion G having a decreasing width, and an extended portion 150E of a module cover 150' may be configured to be inserted into the upper end portion G so that the flash LED module 100A can be arranged adjacent to the camera lens module 450.

[0070] One in Fig. The transmissive hole structure 410' shown in Figure 10 may include a first transmissive hole LH1 corresponding to the lens 150L of the flash LED module 100A and a second transmissive hole LH2 for the camera lens module 450. Since the flash LED module 100A is arranged adjacent to the camera lens module 450, the transmissive hole structure 410' provided in a housing may have a single structure.

[0071] As described above, by modifying a structure of the module cover 150', a mobile device including a camera module in which the components are compactly arranged can be provided.

[0072] In the example embodiment described above, the flash LED module may include the module cover along with the flash LED device and the light sensor mounted on a single substrate, but an example embodiment thereof is not limited thereto. In another example embodiment, the module cover may be pre-mounted in a housing (e.g., an optical opening) of an upper-level product (e.g., a mobile device), and the flash LED module may be provided as a module including the flash LED device and the light sensor mounted on a substrate without a module cover.

[0073] Fig. 11A and Fig. 11B are perspective diagrams illustrating a front and a back, respectively, of a camera-embedded mobile device (e.g., a smartphone) according to an example embodiment.

[0074] With reference to Fig. 11A and Fig. 11B, a mobile device 500 in the example embodiment may include a housing 510 including a first surface 510A (or a front surface), a second surface 510B (or a back surface), and a side surface 510C surrounding a space between the first surface 510A and the second surface 510B.

[0075] In the example embodiment, at least a portion of the first surface 510A may be formed by a front plate 502 (e.g., made of glass or polymer including multiple coatings) configured to be substantially transmissive. The second surface 510B may be formed by a back plate 511 configured to be substantially opaque. The back plate 511 may be formed of coated or colored glass, ceramic, polymer, a metal, or a combination of at least two or more of these materials. The side surface 510C may be combined with the front plate 502 and the back plate 511 and may be formed by a side enclosure structure 518 (or side surface element) including a metal and / or polymer.

[0076] A mobile device 500 in the example embodiment may include at least one or more of a display 501, audio modules 503, 507, and 514, sensor modules 504 and 520, a plurality of camera modules 505 and 550, key input devices 515, 516, and 517, an indicator 506, and connector jacks 508 and 509. In example embodiments, additional elements not shown may be included in the mobile device 500, and one or more of the shown elements may be omitted.

[0077] The display 501 may be exposed through all or part of the front panel 502. Although not shown, the display 501 may be combined with or arranged adjacent to a touch sensor circuit, a pressure sensor that measures the strength (pressure) of a touch, and / or a digitizer that detects a stylus based on a magnetic field.

[0078] Audio modules 503, 507, and 514 may include a microphone jack 503 and speaker jacks 507 and 514. A microphone may be plugged into microphone jack 503 to receive external sound, and in example embodiments, multiple microphones may be arranged to capture a sound direction. Speaker jacks 507 and 514 may include an external speaker jack 507 and a receiver jack 514 for use during a voice call. In example embodiments, speaker jacks 507 and 514 and microphone jack 503 may be integrated and implemented using a single jack, or speakers may be included without speaker jacks 507 and 514.

[0079] The camera modules 505 and 550 can be arranged on the first surface 510A and the second surface 510B of the mobile device 500, respectively. The camera modules 505 and 550 can include a single lens or multiple lenses, an image sensor, and / or an image signal processor.

[0080] The sensor modules 504 and 520 can generate an electrical signal or a data value corresponding to an operating state of the mobile device 500 or an external environmental condition. The sensor modules 504 and 520 can be configured, for example, as proximity sensors. In the flash LED module 100, a light sensor and a flash LED device can be integrated with each other, as in the embodiment described here, and the flash LED module 100 can be arranged next to a camera module 550. The mobile device 500 containing the flash LED module 100, such as a mobile communication terminal, can correct a camera image or control a light source of the mobile device 500, such as the LED package 200 or the like, based on information regarding flicker, color, and / or brightness obtained from the ambient light received in the light sensor 300 of the flash LED module 100.

[0081] In the example embodiment, the flash LED module 100 may be arranged together with another sensor, but an example embodiment thereof is not limited thereto. Only the flash LED module 100 may be arranged without the other sensor module 520. The flash LED module 100 can supply flash light through a single hole LH configured as an optical opening as described above, and can receive ambient light through the hole. In the example embodiment, the flash LED module 100 may only be arranged adjacent to the rear camera module 550, but an example embodiment thereof is not limited thereto. The flash LED module 100 can be configured to be integrated with a light sensor for the front camera module 505.

[0082] The keyboard input devices 515, 516, and 517 may include a home button 515 disposed on the first surface 510A of the housing 510, a touch pad 516 disposed around the home button 515, and / or a side button 517 disposed on the side surface 510C of the housing 510. In example embodiments, the mobile device 500 may not include all or only portions of the elements described above and may be configured to include another input means, such as a function key on the display 501, instead of the elements described above.

[0083] The indicator 506 may be arranged on the first surface 510A of the housing 510. The indicator 506 may provide information about the status of the mobile device 500 in the form of a light and may include an LED. The connection ports 508 and 509 may include the first connection port 508 housing a port (e.g., a USB port) for transmitting power and / or data to or receiving power and / or data from an external electronic device, and / or the second connection port 509 (e.g., a headphone jack) housing a port for transmitting an audio signal to or receiving an audio signal from an external electronic device.

[0084] The flash LED module of the example embodiments can be used for various types of electronic devices including a camera or an image sensor, as well as for the mobile communication terminal described in the above example embodiments.

[0085] According to the above example embodiments, by arranging the light sensor to overlap the flash lens, flash light can be emitted and ambient light can be received for calibrating a camera image by arranging a single hole in a housing of a mobile device.

[0086] While exemplary embodiments have been shown and described above, it will be apparent to those skilled in the art that modifications and variations could be made without departing from the scope of the present inventive concept as defined by the appended claims. As an example, the inventive concept of roughening one or more surfaces of the module to form a visual obstruction against viewing internal components of the LED module is applicable to embodiments in which the light sensor within the LED module has been omitted. In this case, the surface roughening would obstruct the view of the LED package within the LED module.

[0087] As another example, the lens shared by the LED package and the light sensor does not need to be incorporated into the module cover. This means the lens can be located elsewhere, either inside or outside the module cover. Fig. 12 illustrates a modification of Fig. 10, in which the lens 150LC (such as a Fresnel lens) is formed within the light-transmitting region of the outer casing 410C of an electronic device, such as a smartphone. In this case, the module cover 150EC (with or without roughening) is optically transmissive and does not contain a lens as in the previous embodiments. All other elements of Fig. 12 are the same as those previously related to Fig. 10 described.

Claims

[1] Light-emitting diode (LED) module, comprising: a substrate (110) containing a top surface; an LED package (200; 200') containing a light-emitting region (EL) and mounted on top of the substrate (110); a light sensor (300) containing a light receiving area (RL) and mounted on the top side of the substrate (110) horizontally next to the LED package (200; 200'); and a lens (150L; 150LC) aligned vertically above the light-emitting area (EL) of the LED package (200; 200') and at least partially overlapping the light-receiving area (RL) of the light sensor (300), wherein the lens (150L; 150LC) is a Fresnel lens, and wherein a central axis of the Fresnel lens (150L; 150LC) is aligned with a geometric center of the light-emitting region (EL) of the LED package (200; 200'). [2] The LED module according to claim 1, wherein the LED package (200; 200') includes an LED chip (250; 250A; 250B) and a wavelength conversion film (280) configured to emit white light. [3] LED module according to claim 1 or 2, wherein the light sensor (300) is an ambient light sensor and the light receiving area (RL) of the light sensor (300) includes a photodiode array. [4] LED module according to one of claims 1 to 3, wherein the lens (150L; 150LC) completely overlaps the light-emitting area (EL) of the LED package (200; 200') and partially overlaps the light-receiving area (RL) of the light sensor (300). [5] LED module according to one of claims 1 to 4, wherein an outer edge of the Fresnel lens (150L; 150LC) is aligned vertically above the light receiving area (RL) of the light sensor (300). [6] LED module according to one of claims 1 to 5, wherein the Fresnel lens (150L; 150LC) has a field of view (FOV) of at least 100°. [7] The LED module according to any one of claims 1 to 6, wherein a bottom surface of the Fresnel lens (150L; 150LC) has a central light-condensing concavity located above the light-emitting region (EL) of the LED package (200; 200'). [8] LED module according to one of claims 1 to 7, wherein the LED package (200; 200') has a reflective side wall (260) arranged between the light-emitting region (EL) and the light sensor (300). [9] LED module according to claim 8, wherein the reflective side wall (260) of the LED package (200; 200') surrounds the light-emitting region (EL) of the LED package (200; 200'). [10] LED module according to one of claims 1 to 9, wherein the horizontal distance (d) between the LED package (200; 200') and the light sensor (300) is 300 µm or less. [11] The LED module of any one of claims 1 to 10, further comprising a module cover (150; 150') extending over the substrate (110) and defining a top wall of the LED module, wherein the lens (150L) is formed in the module cover (150; 150'). [12] The LED module of claim 11, wherein an underside of the module cover (150; 150') is roughened to form a visual obstruction of the LED package (200; 200') and the light sensor (300) when viewed through the module cover (150; 150'). [13] Light-emitting diode (LED) module, comprising: a substrate (110) containing a top surface; an LED package (200; 200') containing a light-emitting region (EL) and mounted on top of the substrate (110); an ambient light sensor (300) containing a light receiving area (RL) and mounted on the top side of the substrate (110) horizontally next to the LED package (200; 200'); and a module cover (150; 150') formed of light-transmitting material and extending over the substrate (110) to define a top wall of the LED module, wherein a portion of the module cover (150; 150') has a Fresnel lens (150L) aligned vertically above the light-emitting region (EL) of the LED package (200; 200') and at least partially overlapping the light-receiving region (RL) of the ambient light sensor (300), wherein the LED package (200; 200') includes an LED chip (250; 250A; 250B) and a wavelength conversion film (280) arranged over the LED chip (250; 250A; 250B), and wherein the LED package (200; 200') further includes a reflective structure (260) having vertical sidewalls surrounding the LED chip (250; 250A; 250B) and the wavelength conversion film (280) to prevent light emission from side surfaces of the LED chip (250; 250A; 250B) and the wavelength conversion film (280). [14] The LED module according to claim 13, wherein the reflective structure (260) is formed of a resin material containing a reflective powder. [15] The LED module according to claim 13 or 14, wherein the LED package (200; 200') further comprises a light-transmitting film (290) disposed over the wavelength conversion film (280), and wherein the vertical side walls further surround the light-transmitting film (290) to obstruct light emission from side surfaces of the light-transmitting film (290). [16] Light-emitting diode (LED) module, comprising: a substrate (110) containing a top surface; an LED package (200; 200') containing a light-emitting region (EL) and mounted on top of the substrate (110); and a module cover (150; 150') formed of a transmissive material and extending over the substrate (110) to define a top wall of the LED module, wherein a portion of the module cover (150; 150') includes a lens (150) aligned over the light-emitting region (EL) of the LED package (200; 200'), wherein an underside (150L') of at least the lens (150L) of the module cover (150; 150') is roughened to form a visual obstruction against viewing the LED package (200; 200') through the lens (150L) from outside the module cover (150; 150'). [17] The LED module according to claim 16, wherein the lens (150L) is a Fresnel lens. [18] The LED module of claim 16 or 17, further comprising an ambient light sensor (300) mounted on top of the substrate (110) horizontally adjacent to the LED package (200; 200').

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