Projection device and electronic device including the same

Abstract

Embodiments provide a projection device, including: a light guide; a first light source disposed at a first side of the light guide; the lens group is arranged at the fourth side part of the light guide; and a first side lens disposed between a first side portion of the light guide and the first light source, in which: the lens group includes first to Nth lenses; a first lens positioned farthest from a fourth side of the light guide; a first side portion of the light guide and a fourth side portion of the light guide overlap in an optical axis direction of the lens group; and the first side lens and the Nth lens are in contact with the light guide.

Description

Technical Field

[0001] Embodiments relate to a projection device and an electronic device including the projection device. Background Art

[0002] Virtual reality (VR) technology refers to a technology that creates a specific environment or situation that is similar to reality but not real, created by artificial technology such as using a computer.

[0003] Augmented reality (AR) technology refers to the technology that synthesizes virtual objects or information into the real environment to make the objects appear as if they already exist in the original environment.

[0004] Mixed reality (MR) or mixed reality technology refers to a technology that creates a new environment or new information by combining the virtual world and the real world. In particular, MR refers to a technology that enables the interaction between things existing in the real world and things existing in the virtual world to be performed in real time.

[0005] In this case, the created virtual environment or situation stimulates the five senses of the user and allows the user to move freely between reality and imagination by providing a space and time experience similar to reality. In addition, the user can not only simply immerse himself or herself in such an environment, but also interact with things realized in such an environment by manipulating or giving commands using real devices.

[0006] Recently, research on devices (equipment and apparatus) used in such technical fields has been actively conducted. However, miniaturization and improved optical performance of such devices are required. Summary of the invention

[0007] [Technical issues]

[0008] An embodiment provides a projection device and an electronic device, wherein a lens is bonded to a surface of a light guide through which light is emitted, so that total reflection does not occur on an outer surface of the light guide (e.g., a prism), and thus stray light is removed when using the projection device for augmented reality (AR) or the like and an electronic device including the projection device.

[0009] In addition, the embodiments provide a projection device and an electronic device having a reduced total track length (TTL).

[0010] The problems to be solved in the implementation manner are not limited thereto, and it can be said that they also include purposes or effects that can be understood from the “technical solution” or “specific implementation manner” to be described below.

[0011] [Technical solution]

[0012] According to an embodiment, a projection device includes: a light guide; a first light source, which is arranged on a first side of the light guide; a lens group, which is arranged on a fourth side of the light guide; and a first side lens, which is arranged between the first side of the light guide and the first light source, wherein the lens group includes first to N-th lenses, the first lens is arranged to be farthest from the fourth side of the light guide, the first side of the light guide overlaps with the fourth side of the light guide in the optical axis direction of the lens group, and the first side lens and the N-th lens are in contact with the light guide.

[0013] The Nth lens in the lens group may be disposed closest to the light guide.

[0014] The projection device may also include: a second light source, which is arranged on the second side of the light guide; a third light source, which is arranged on the third side of the light guide; a second side lens, which is arranged between the second side of the light guide and the second light source; and a third side lens, which is arranged between the third side of the light guide and the third light source.

[0015] The surface of the first side lens adjacent to the first light source may be convex, the surface of the second side lens adjacent to the second light source may be convex, the surface of the third side lens adjacent to the third light source may be convex, and the surfaces of the first side lens, the second side lens and the third side lens adjacent to each light source may have the same radius of curvature.

[0016] The first optical axes of the first and fourth sides of the light guide may be orthogonal to the second optical axes of the second and third sides of the light guide.

[0017] A distance from the first lens to the first light source may be less than or equal to twice the focal lengths of the lens group, the light guide, and the first side lens.

[0018] A surface of the first lens facing the light guide may be convex in a direction opposite to a direction toward the light guide.

[0019] The size of the light guide may be larger than the size of the light source.

[0020] The first side lens may have a size smaller than a size of the first side portion of the light guide.

[0021] The size or effective diameter of the light guide may be larger than the size or effective diameter of at least one lens among the first to Nth lenses of the lens group.

[0022] [Beneficial Effects]

[0023] An embodiment implements a projection device and an electronic device, wherein a lens is bonded to a surface of a light guide through which light is emitted, so that total reflection does not occur on an outer surface of the light guide (e.g., a prism), and thus stray light is removed when using the projection device for augmented reality (AR) or the like and an electronic device including the projection device.

[0024] In addition, a projection device and an electronic device having a reduced total track length (TTL) can be realized.

[0025] In addition, a projection device and an electronic device in which the occurrence of flare is minimized and the light source is easily miniaturized can be realized.

[0026] Various beneficial advantages and effects of the present invention are not limited to the above contents and will be more easily understood in the process of describing the specific embodiments of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a conceptual diagram illustrating an embodiment of an artificial intelligence (AI) device.

[0028] Figure 2 is a block diagram showing a configuration of an extended reality electronic device according to an embodiment of the present invention.

[0029] Figure 3 is a perspective view of an augmented reality electronic device according to a first embodiment of the present invention.

[0030] Figures 4 to 6 is a conceptual diagram for describing various display types applicable to a display unit according to an embodiment of the present invention.

[0031] Figure 7 is a perspective view of a projection device according to one embodiment.

[0032] Figure 8 is an exploded perspective view of a projection device according to one embodiment.

[0033] Fig. 9 2 is a view describing coupling of an outer lens, a first spacer, a light guide, a lens, and a second spacer with a barrel in a projection device according to an embodiment.

[0034] Fig.10 2 is a view describing coupling between a barrel, a housing, and an additional housing in a projection device according to an embodiment.

[0035] Fig.11 is a view describing coupling between a housing and a light source unit in a projection device according to one embodiment.

[0036] Fig.12is a view of an optical system of the projection device according to the first embodiment.

[0037] Fig.13 is a perspective view of a light guide, a fourth lens, and a side lens in a projection device according to an embodiment.

[0038] Fig.14 is another perspective view of the light guide, the fourth lens, and the side lenses in the projection device according to the embodiment.

[0039] Fig.15 is a view of an optical system of a projection device according to a second embodiment. DETAILED DESCRIPTION

[0040] Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[0041] However, the technical spirit of the present invention is not limited to some of the described embodiments, but can be implemented in various different forms, and one or more of the components in the embodiments can be used by selective connection or replacement without departing from the scope of the technical spirit of the present invention.

[0042] In addition, unless explicitly specifically defined and described, the terms (including technical terms and scientific terms) used in the embodiments of the present invention may be interpreted as the meanings commonly understood by technicians in the field to which the present invention belongs, and the meanings of commonly used terms, such as terms defined in dictionaries, may be interpreted in consideration of their contextual meanings in the relevant field.

[0043] In addition, the terms used in the embodiments of the present invention are used to describe the embodiments and are not intended to limit the present invention.

[0044] In the specification, unless the context clearly dictates otherwise, a singular form may include a plural form, and when described as "at least one (or one or more) of A, B, and C", it may include one or more of all possible combinations of A, B, and C.

[0045] In addition, terms such as first, second, A, B, (a), and (b) may be used to describe components of embodiments of the present invention.

[0046] These terms are used only for the purpose of distinguishing one component from another component, and the nature, order, sequence, etc. of the corresponding components are not limited by these terms.

[0047] In addition, when a first component is described as being “connected,” “coupled” or “coupled” to a second component, it may include not only a case where the first component is directly connected, coupled or coupled to the second component, but also a case where the first component is “connected,” “coupled” or “coupled” to the second component through another component existing between the first and second components.

[0048] In addition, when a first component is described as being formed or disposed “on (above) or below (below)” a second component, “on (above)” or “below (below)” may include not only a case where the two components are in direct contact with each other, but also a case where one or more third components are formed or disposed between the two components. In addition, when expressed as “on (above) or below (below)”, it may include not only a meaning based on an upward direction of one component, but also a meaning based on a downward direction of one component.

[0049] Figure 1 is a conceptual diagram illustrating an embodiment of an artificial intelligence (AI) device.

[0050] Reference Figure 1 , at least one of the AI ​​server 16, the robot 11, the autonomous vehicle 12, the extended reality (XR) device 13, the smart phone 14, and the home appliance 15 included in the AI ​​system is connected to the cloud network 10. Here, the robot 11, the autonomous vehicle 12, the XR device 13, the smart phone 14, the home appliance 15, etc., to which the AI ​​technology is applied may be referred to as AI devices 11 to 15.

[0051] The cloud network 10 may be a network that constitutes a part of a cloud computing infrastructure or exists in a cloud computing infrastructure. Here, the cloud network 10 may be formed using a 3G network, a 4G or Long Term Evolution (LTE) network, or a 5G network.

[0052] That is, the devices 11 to 16 constituting the AI ​​system may be connected to each other through the cloud network 10. In particular, the devices 11 to 16 may communicate with each other through a base station, or may directly communicate with each other without using a base station.

[0053] The AI ​​server 16 may include a server that performs AI processing and a server that performs operations on big data.

[0054] The AI ​​server 16 is connected to at least one of the AI ​​devices constituting the AI ​​system, such as a robot 11, an autonomous vehicle 12, an XR device 13, a smart phone 14, and a home appliance 15, via a cloud network 10, and can assist at least a portion of the AI ​​processing of the connected AI devices 11 to 15.

[0055] In this case, the AI server 16 can train an artificial neural network on behalf of the AI devices 11 to 15 according to a machine learning algorithm, store the learning model therein, or send the learning model to the AI devices 11 to 15.

[0056] In this case, the AI server 16 can receive input data from the AI devices 11 to 15, infer a result value of the received input data using the learning model, generate a response or a control command based on the inferred result value, and send the response or the control command to the AI devices 11 to 15.

[0057] Alternatively, the AI devices 11 to 15 can directly use the learning model to infer a result value of the input data and generate a response or a control command based on the inferred result value.

[0058] <AI+Robot>

[0059] The robot 11 can be implemented as a guiding robot, a transportation robot, a cleaning robot, a wearable robot, an entertainment robot, a pet robot, an unmanned aerial robot, etc. that apply AI technology.

[0060] The robot 11 can include a robot control module for controlling actions, and the robot control module can be a software module or a chip as hardware implementing the software module.

[0061] The robot 11 can use sensor information obtained from various types of sensors to obtain the state information of the robot 11, detect (identify) the surrounding environment and nearby objects, generate map data, determine a movement path and a driving plan, determine a response to user interaction, or determine an action.

[0062] Here, the robot 11 can use sensor information obtained from at least one of a lidar, a radar, and a camera to determine a movement path and a driving plan.

[0063] The robot 11 can use a learning model composed of at least one artificial neural network to perform the above operations. For example, the robot 11 can use the learning model to identify the surrounding environment and nearby objects, and use the identified surrounding environment information or nearby object information to determine an action. Here, the learning model can be directly trained in the robot 11 or trained in an external device such as the AI server 16.

[0064] In this case, the robot 11 can perform an action when directly using the learning model to generate a result, or send the sensor information to an external device such as the AI server 16 and perform an action when receiving the correspondingly generated result.

[0065] The robot 11 can determine a motion path and a driving plan using at least one of map data, object information detected from sensor information, and object information obtained from an external device, and can control the driving unit to drive the robot 11 according to the determined motion path and driving plan.

[0066] The map data may include object recognition information about various objects provided in the space where the robot 11 moves. For example, the map data may include object recognition information about fixed objects such as walls and doors and repositionable objects such as flower pots and tables. Additionally, the object recognition information may include a name, type, distance, position, and the like.

[0067] In addition, the robot 11 can perform an action or travel by controlling the driving unit based on user control or interaction with the user. In this case, the robot 11 can obtain interaction intention information according to the user's action or speech utterance, and perform an action when determining a response based on the obtained intention information.

[0068] <AI + Autonomous Driving>

[0069] The autonomous vehicle 12 can be implemented as a mobile robot, a vehicle, an unmanned aerial vehicle, etc. that apply AI technology.

[0070] The autonomous vehicle 12 may include an autonomous driving control module for controlling the autonomous driving function, and the autonomous driving control module may be a software module or a chip that is hardware for implementing the software module. The autonomous driving control module may be included in the autonomous vehicle 12 as a component of the autonomous vehicle 12, or formed as separate hardware and connected to the outside of the autonomous vehicle 12.

[0071] The autonomous vehicle 12 can use sensor information obtained from various types of sensors to obtain the state information of the autonomous vehicle 12, detect (recognize) the surrounding environment and nearby objects, generate map data, determine a motion path and a driving plan, or determine an action.

[0072] Here, the autonomous vehicle 12 can determine a motion path and a driving plan using sensor information obtained from at least one of a lidar, a radar, and a camera, like the robot 11.

[0073] In particular, the autonomous vehicle 12 can identify the environment or objects in an area where the field of view is blocked or an area beyond a certain distance by receiving sensor information from an external device or directly receiving information recognized by the external device from the external device.

[0074] The autonomous vehicle 12 may perform the above operations using a learning model composed of at least one artificial neural network. For example, the autonomous vehicle 12 may use the learning model to identify the surrounding environment and nearby objects, and determine a driving route using the identified surrounding environment information or nearby object information. Here, the learning model may be trained directly in the autonomous vehicle 12, or in an external device such as the AI ​​server 16.

[0075] In this case, the autonomous vehicle 12 may perform an action when directly using the learning model to generate a result, or send sensor information to an external device such as the AI ​​server 16 and perform an action when receiving the corresponding generated result.

[0076] The autonomous vehicle 12 may determine a motion path and a driving plan using at least one of map data, object information detected from sensor information, and object information acquired from an external device, and the autonomous vehicle 12 may control a driving unit to drive the autonomous vehicle 12 according to the determined motion path and driving plan.

[0077] The map data may include object recognition information about various objects disposed in a space (e.g., a road) in which autonomous vehicle 12 is traveling. For example, the map data may include object recognition information about fixed objects such as street lamps, rocks, and buildings, and movable objects such as vehicles and pedestrians. In addition, the object recognition information may include name, type, distance, location, etc.

[0078] In addition, the autonomous vehicle 12 can perform actions or travel by controlling the driving unit based on the user's control or interaction with the user. In this case, the autonomous vehicle 12 can obtain interaction intention information based on the user's action or voice utterance, and perform actions when a response is determined based on the obtained intention information.

[0079] <AI+XR>

[0080] The XR device 13 can be implemented as a head-mounted display (HMD) applying AI technology, a head-up display (HUD) set in a vehicle, a television, a mobile phone, a smart phone, a computer, a wearable device, a home appliance, a digital signage, a vehicle, a fixed robot, a mobile robot, etc.

[0081] The XR device 13 can obtain information about the surrounding space or real objects by analyzing 3D point cloud data or image data obtained through various sensors or from external devices to generate position data and attribute data of 3D points, and can render the XR object to be output. For example, the XR device 13 can output an XR object containing additional information about the recognized object to correspond to the recognized object.

[0082] The XR device 13 can perform the above operations using a learning model composed of at least one artificial neural network. For example, the XR device 13 can use the learning model to identify real objects from 3D point cloud data or image data and provide information corresponding to the identified real objects. Here, the learning model can be directly trained in the XR device 13 or in an external device such as the AI server 16.

[0083] In this case, the XR device 13 can perform an action when directly using the learning model to generate a result, or send sensor information to an external device such as the AI server 16 and perform an action when receiving the corresponding generated result.

[0084] <AI + Robot + Autonomous Driving>

[0085] The robot 11 can be implemented as a guiding robot, a transport robot, a cleaning robot, a wearable robot, an entertainment robot, a pet robot, an unmanned flying robot, etc. that apply AI technology and autonomous driving technology.

[0086] The robot 11 that applies AI technology and autonomous driving technology can be the robot itself with autonomous driving function or the robot 11 that interacts with the autonomous vehicle 12.

[0087] The robot 11 with autonomous driving function can be a general term for a device that moves along a given path by itself or determines a path by itself without user control.

[0088] The robot 11 with autonomous driving function and the autonomous vehicle 12 can use a common sensing method to determine one or more of the movement path and the driving plan. For example, the robot 11 with autonomous driving function and the autonomous vehicle 12 can use the information sensed by lidar, radar, or camera to determine one or more of the movement path and the driving plan.

[0089] The robot 11 that interacts with the autonomous vehicle 12 can exist independently of the autonomous vehicle 12 and can be associated with the autonomous driving function inside or outside the autonomous vehicle 12, or perform actions associated with the user riding in the autonomous vehicle 12.

[0090] In this case, the robot 11 that interacts with the autonomous vehicle 12 can control or assist the autonomous driving function of the autonomous vehicle 12 by obtaining sensor information on behalf of the autonomous vehicle 12 and providing the sensor information to the autonomous vehicle 12, or by obtaining sensor information, generating surrounding environment information or nearby object information and providing the surrounding environment information or nearby object information to the autonomous vehicle 12.

[0091] Alternatively, the robot 11 that interacts with the autonomous vehicle 12 may monitor a user riding in the autonomous vehicle 12 or control functions of the autonomous vehicle 12 through interaction with the user. For example, when it is determined that the driver is drowsy, the robot 11 may activate the autonomous driving function of the autonomous vehicle 12 or may assist in controlling the driving unit of the autonomous vehicle 12. Here, the functions of the autonomous vehicle 12 controlled by the robot 11 may include functions provided by a navigation system or an audio system installed in the autonomous vehicle 12 and the autonomous driving function.

[0092] Alternatively, the robot 11 that interacts with the autonomous vehicle 12 may provide information to the autonomous vehicle 12 or provide an auxiliary function from outside the autonomous vehicle 12. For example, the robot 11 may provide traffic information including signal information, etc. to the autonomous vehicle 12 like an intelligent traffic light, or may interact with the autonomous vehicle 12 like an automatic charger for an electric vehicle to automatically connect the charger to a charging port.

[0093] <AI+Robot+XR>

[0094] The robot 11 may be implemented as a guiding robot, a transport robot, a cleaning robot, a wearable robot, an entertainment robot, a pet robot, an unmanned flying robot, a drone, etc. that apply AI technology and XR technology.

[0095] The robot 11 that applies XR technology may be a robot that is an object for control or interaction in an XR image. In this case, the robot 11 is different from the XR device 13 and may be associated with the XR device 13.

[0096] When the robot 11 that is an object for control or interaction in an XR image acquires sensor information from a sensor including a camera, the robot 11 or the XR device 13 may generate an XR image based on the sensor information, and the XR device 13 may output the generated XR image. In addition, the robot 11 may operate based on a control signal input through the XR device 13 or interaction with the user.

[0097] For example, the user may check an XR image corresponding to the viewpoint of the remotely associated robot 11 through an external device such as the XR device 13, and may adjust the autonomous driving path of the robot 11, control the operation or driving of the robot 11, or check information about surrounding objects of the robot 11 through interaction.

[0098] <AI+Autonomous Driving+XR>

[0099] The autonomous vehicle 12 may be implemented as a mobile robot, a vehicle, an unmanned aerial vehicle, etc. that apply AI technology and XR technology.

[0100] The autonomous vehicle 12 to which the XR technology is applied may be an autonomous vehicle equipped with a device for providing an XR image, an autonomous vehicle as an object of control or interaction in the XR image, etc. In particular, the autonomous vehicle 12 as an object of control or interaction in the XR image is different from the XR device 13 and may be associated with the XR device 13.

[0101] The autonomous vehicle 12 equipped with a device for providing an XR image can acquire sensor information from sensors including a camera and output an XR image generated based on the acquired sensor information. For example, the autonomous vehicle 12 can be equipped with a HUD to output an XR image, thereby providing an occupant with an XR object corresponding to a real object or an object on a screen.

[0102] In this case, when the XR object is output to the HUD, at least a portion of the XR object may be output so as to overlap with a real object to which the occupant's gaze is directed. On the other hand, when the XR object is output to a display installed in the autonomous vehicle 12, at least a portion of the XR object may be output so as to overlap with an object on the screen. For example, the autonomous vehicle 12 may output an XR object corresponding to an object such as a lane, another vehicle, a traffic light, a traffic sign, a two-wheeled vehicle, a pedestrian, a building, and the like.

[0103] When the autonomous vehicle 12 as the object of control or interaction in the XR image acquires sensor information from a sensor including a camera, the autonomous vehicle 12 or the XR device 13 may generate an XR image based on the sensor information, and the XR device 13 may output the generated XR image. In addition, the autonomous vehicle 12 may operate based on a control signal input through an external device such as the XR device 13 or an interaction with a user.

[0104] [XR Technology]

[0105] XR is a general term for virtual reality (VR), augmented reality (AR), and mixed reality (MR). VR technology is a computer graphics (CG) technology that provides only real-world objects or backgrounds as CG images, AR technology is a CG technology that provides virtual CG images on images of real objects, and MR technology is a CG technology that mixes and combines virtual objects with the real world.

[0106] MR technology is similar to AR technology in that it displays real objects and virtual objects together. However, the difference is that while AR technology uses virtual objects to supplement real objects, MR technology uses virtual objects and real objects with the same characteristics.

[0107] XR technology can be applied to HMD, HUD, mobile phones, tablet PCs, laptop PCs, desktop PCs, TVs, digital signage, etc., and a device to which XR technology is applied may be referred to as an XR device.

[0108] Hereinafter, an electronic device providing XR according to an embodiment of the present invention will be described. In particular, a projection device applied to AR and an electronic device including the projection device will be described in detail.

[0109] Figure 2 is a block diagram showing the configuration of the XR electronic device 20 according to an embodiment of the present invention.

[0110] Reference Figure 2 The XR electronic device 20 may include a wireless communication unit 21, an input unit 22, a sensing unit 23, an output unit 24, an interface unit 25, a memory 26, a control unit 27, and a power supply unit 28. Figure 2 The components illustrated in FIG. 2 are not necessary to implement the electronic device 20 , and thus the electronic device 20 described in this specification may have more or fewer components than those listed above.

[0111] More specifically, among the above components, the wireless communication unit 21 may include one or more modules capable of wireless communication between the electronic device 20 and a wireless communication system, between the electronic device 20 and another electronic device, or between the electronic device 20 and an external server. In addition, the wireless communication unit 21 may include one or more modules that connect the electronic device 20 to one or more networks.

[0112] The wireless communication unit 21 may include at least one of a broadcast receiving module, a mobile communication module, a wireless Internet module, a short-range communication module, and a location information module.

[0113] The input unit 22 may include a camera or an image input unit for inputting an image signal, a microphone or an audio input unit for inputting an audio signal, and a user input unit (e.g., a touch key, a mechanical key, etc.) for receiving information from a user. Voice data or image data collected from the input unit 22 may be analyzed and processed using a user's control command.

[0114] The sensing unit 23 may include one or more sensors for sensing at least one of information in the electronic device 20 , information about an environment around the electronic device 20 , and user information.

[0115] For example, the sensing unit 23 may include at least one of a proximity sensor, an illumination sensor, a touch sensor, an acceleration sensor, a magnetic sensor, a G sensor, a gyro sensor, a motion sensor, an RGB sensor, an infrared sensor (IR sensor), a finger scan sensor, an ultrasonic sensor, an optical sensor (e.g., a camera), a microphone, a battery gauge, an environmental sensor (e.g., a barometer, a hygrometer, a thermometer, a radiation detection sensor, a heat detection sensor, a gas detection sensor, etc.), and a chemical sensor (e.g., an electronic nose, a healthcare sensor, a biometric sensor, etc.). Meanwhile, the electronic device 20 disclosed in the present specification may utilize in combination the types of information sensed by at least two of these sensors.

[0116] The output unit 24 is used to generate output related to vision, hearing or touch, and may include at least one of a display unit, an audio output unit, a tactile module and an optical output unit. The display unit may implement a touch screen by forming a mutual layer structure of a display unit and a touch sensor or integrally forming the display unit and the touch sensor. Such a touch screen may be used as a user input device that provides an input interface between the AR electronic device 20 and the user, and may also provide an output interface between the AR electronic device 20 and the user.

[0117] The interface unit 25 serves as a passage for various types of external devices connected to the electronic device 20. Through the interface unit 25, the electronic device 20 can receive VR or AR content from the external device and exchange various input signals, sensing signals, and data types to perform mutual interaction.

[0118] For example, the interface unit 25 may include at least one of a wired or wireless headset port, an external charger port, a wired or wireless data port, a memory card port, a port for connecting a device equipped with an identification module, an audio I / O (input / output) port, a video I / O (input / output) port, and a headphone port.

[0119] In addition, the memory 26 stores data supporting various functions of the electronic device 20. The memory 26 may store a plurality of application programs (or applications) driven by the electronic device 20, data for the operation of the electronic device 20, and commands. At least some of these applications may be downloaded from an external server via wireless communication. In addition, at least some of these applications may exist in the electronic device 20 from the time of shipment of the basic functions of the electronic device 20 (e.g., call receiving and outgoing functions, and message receiving and sending functions).

[0120] The control unit 27 generally controls the overall operation of the electronic device 20 in addition to controlling the operation related to the application program. The control unit 27 may process signals, data, information, etc. input or output through the above-mentioned components.

[0121] In addition, the control unit 27 can control at least some of the components to provide appropriate information or processing functions to the user by running the application program stored in the memory 26. In addition, the control unit 27 can operate at least two of the components included in the electronic device 20 in combination to run the application program.

[0122] In addition, the control unit 27 may detect the motion of the electronic device 20 or the user using a gyro sensor, a gravity sensor, a motion sensor, etc. included in the sensing unit 23. Alternatively, the control unit 27 may detect an object approaching the electronic device 20 or the user using a proximity sensor, an illumination sensor, a magnetic sensor, an infrared sensor, an ultrasonic sensor, a light sensor, etc. included in the sensing unit 23. In addition, the control unit 27 may detect the motion of the user through a sensor provided in a controller operating in conjunction with the electronic device 20.

[0123] In addition, the control unit 27 may perform operations (or functions) of the electronic device 20 using application programs stored in the memory 26 .

[0124] The power supply unit 28 receives external power or internal power under the control of the control unit 27, and supplies power to each component included in the electronic device 20. The power supply unit 28 includes a battery, and the battery may be provided in a built-in or replaceable form.

[0125] At least some of the above components can cooperate with each other to implement the operation, control or control method of the electronic device according to various embodiments described below. In addition, the operation, control or control method of the electronic device can be implemented on the electronic device by running at least one application stored in the memory 26.

[0126] Hereinafter, the electronic device described as an example of the present invention will be described based on the implementation applied to the HMD. However, the implementation of the electronic device according to the present invention may include a mobile phone, a smart phone, a laptop computer, a digital broadcast terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation device, a tablet PC, a tablet PC, an ultrabook, a wearable device, etc. In addition to the HMD, the wearable device may also include a smart watch, a contact lens, VR / AR / MR glasses, etc.

[0127] Figure 3 is a perspective view of an AR electronic device according to an embodiment of the present invention.

[0128] like Figure 3 As illustrated in FIG. 1 , the electronic device according to the embodiment of the present invention may include a frame 100 , a projection device 200 , and a display unit 300 .

[0129] The electronic device may be provided as a glasses type (smart glasses). The glasses type electronic device is worn on the head of a human body, and for this purpose may be provided with a frame (housing, housing, etc.) 100. The frame 100 may be made of a flexible material for easy wearing.

[0130] The frame 100 is supported on the head and provides a space for installing various components. As shown, electronic components such as the projection device 200, the user input unit 130, the audio output unit 140, etc. can be installed on the frame 100. In addition, a lens covering at least one of the left eye and the right eye can be detachably installed on the frame 100.

[0131] The frame 100 may have a form of glasses worn on the user's face as shown in the figure, but the present invention is not necessarily limited thereto, and the frame 100 may have a form such as goggles worn in close contact with the user's face.

[0132] The frame 100 may include a front frame 110 having at least one opening and a y-direction (in the y direction) intersecting the front frame 110. Figure 3 A pair of side frames 120 extending parallel to each other on the upper side.

[0133] In the frame 100 , the length DI in the x-direction and the length LI in the y-direction may be the same or different.

[0134] The projection device 200 is configured to control various electronic components provided in the electronic device. The projection device 200 may be used interchangeably with "light output device", "light projection device", "light radiating device", "optical device" and the like.

[0135] The projection device 200 may generate an image displayed to a user or a video as a series of images. The projection device 200 may include an image source panel that generates an image and a plurality of lenses that diffuse and converge light generated from the image source panel.

[0136] The projection device 200 may be fixed to any one of the two side frames 120. For example, the projection device 200 may be fixed to the inside or outside of one of the side frames 120, or may be integrally formed to be embedded in one of the side frames 120. Alternatively, the projection device 200 may be fixed to the front frame 110 or provided separately from the electronic device.

[0137] The display unit 300 can be implemented in the form of an HMD. The form of an HMD refers to a display type in which the display unit is mounted on the head to display an image directly in front of the user's eyes. When the user wears the electronic device, the display unit 300 can be arranged to correspond to at least one of the left eye and the right eye so as to provide an image directly in front of the user's eyes. In this figure, the display unit 300 is located in a portion corresponding to the right eye so as to output an image toward the user's right eye. However, as described above, the present invention is not limited thereto, and the display unit can be arranged on both the left eye and the right eye.

[0138] The display unit 300 may allow the user to see an image generated by the projection device 200 while visually perceiving an external environment. For example, the display unit 300 may project an image onto a display area using a prism.

[0139] The display unit 300 may be formed transparent so that the projected image and the general field of view in front (the range that the user sees through his / her eyes) are seen at the same time. For example, the display unit 300 may be translucent and may be made of an optical element including glass.

[0140] The display unit 300 may be inserted into and fixed in the opening included in the front frame 110, or may be located behind the opening (i.e., between the opening and the user) and fixed to the front frame 110. The figure illustrates an example in which the display unit 300 is located at the back of the opening and fixed to the front frame 110, but the display unit 300 may be provided and fixed at various positions on the frame 100.

[0141] like Figure 3 As illustrated in , in the electronic device, the projection device 200 projects image light to one side of the display unit 300 , and the image light is emitted to the other side through the display unit 300 , thereby allowing the user to see the image generated by the projection device 200 .

[0142] Therefore, when the user views the external environment through the opening of the frame 100, the user can see the image generated by the projection device 200. That is, the image output by the display unit 300 may appear to overlap with the general field of view. The electronic device can utilize these display characteristics to provide AR, in which a virtual image is superimposed on a real-world image or background to create a single image.

[0143] In addition to this operation, the external environment and the image generated in the projection device 200 can be provided to the user in a short period of time with a time difference that cannot be recognized by the person. For example, in one section of the frame, the external environment can be provided to the person, and in another section, the image from the projection device 200 can be provided to the person.

[0144] Alternatively, both overlap and time difference may be provided.

[0145] Figures 4 to 6 is a conceptual diagram for describing various display types applicable to a display unit according to an embodiment of the present invention.

[0146] Specifically, Figure 4 is a view for describing an embodiment of a prism-type optical element, Figure 5 is a view for describing an embodiment of a waveguide type optical element, and Figure 6 It is a view for describing an embodiment of a surface reflective optical element.

[0147] like Figure 4 As illustrated in FIG. 1 , the display unit 300 - 1 according to the embodiment of the present invention may use a prism-type optical element.

[0148] As an example, Figure 4 As shown in (a) of FIG. 1 , a flat glass optical element in which a surface 300a on which image light is incident and from which image light is emitted is flat can be used as a prism-type optical element, or as Figure 4 As illustrated in (b) of FIG. 1 , a free-form glass optical element in which a surface 300 b from which image light is emitted is formed as a curved surface without a constant radius of curvature may be used as a prism-type optical element.

[0149] The flat glass optical element can receive the image light generated in the projection device 200 through a flat side surface, reflect the image light through the total reflection mirror 300a disposed therein, and emit the image light toward the user. Here, the total reflection mirror 300a disposed inside the flat glass optical element can be formed inside the flat glass optical element by laser.

[0150] The free form glass optical element is formed such that the thickness decreases in a direction away from the incident surface, and thus image light generated in the projection device 200 may be incident on the curved side surface, totally reflected inside, and emitted toward a user.

[0151] like Figure 5 As shown in FIG. 1 , the display unit 300-2 according to another embodiment of the present invention may use a waveguide optical element or a light guide optical element (LOE).

[0152] Examples of waveguide or lightguide optical elements include: Figure 5 The segmented beam splitter type glass optical element shown in (a) is as follows Figure 5 The sawtooth prism type glass optical element shown in (b) of FIG. Figure 5 The glass optical element with a diffractive optical element (DOE) shown in (c) of FIG. Figure 5The glass optical element with a holographic optical element (HOE) shown in (d) of FIG. Figure 5 The glass optical element with a passive grating as shown in (e) of Figure 5 A glass optical element with an active grating is shown in (f).

[0153] like Figure 5 As illustrated in (a) of FIG. 1 , the segmented beam splitter type glass optical element may be provided with a total reflection mirror 301a on the side where the image light is incident and a partial reflection mirror (segmented beam splitter) 301b on the side where the image light is emitted.

[0154] Therefore, the image light generated in the projection device 200 can be totally reflected by the total reflection mirror 301a inside the glass optical element, and the totally reflected image light can be partially separated and emitted by the partial reflection mirror 301b while being guided in the longitudinal direction of the glass and recognized by the user's eyes.

[0155] like Figure 5 As illustrated in (b), in a sawtooth prism type glass optical element, the image light of the projection device 200 can be incident on the side surface of the glass obliquely, totally reflected inside the glass, emitted to the outside of the glass by the sawtooth-shaped uneven portion 302 provided on the side emitting the image light, and recognized by the user's eyes.

[0156] like Figure 5 As illustrated in (c) of FIG. 1 , the glass optical element having DOE may be provided with a first diffraction element 303a on the surface on which the image light is incident, and a second diffraction element 303b on the surface through which the image light is emitted. The first diffraction element 303a and the second diffraction element 303b may be provided in the form of forming a specific pattern on the surface of the glass or attaching a separate diffraction film thereon.

[0157] Therefore, the image light generated in the projection device 200 can be diffracted by the first diffraction element 303a when entering the glass, totally reflected, guided along the longitudinal direction of the glass, emitted through the second diffraction element 303b, and recognized by the user's eyes.

[0158] like Figure 5 As illustrated in (d) of FIG. 1 , the glass optical element having the HOE may be provided with an outcoupler 304 inside the glass on the side through which the image light is emitted. Therefore, the image light may be incident on the side surface of the glass obliquely from the projection device 200, be totally reflected, be guided in the longitudinal direction of the glass, be emitted by the outcoupler 304, and be recognized by the user's eyes. The HOE may be further divided into a structure having a passive grating and a structure having an active grating, in which the structure is slightly changed.

[0159] like Figure 5 As illustrated in (e) of FIG. 1 , the glass optical element having a passive grating may be provided with an in-coupler 305a on a surface opposite to the glass surface on which the image light is incident, and an out-coupler 305b on a surface opposite to the glass surface through which the image light is emitted. Here, the in-coupler 305a and the out-coupler 305b may be provided in the form of a film having a passive grating.

[0160] Therefore, the image light incident on the incident side surface of the glass can be totally reflected by the in-coupler 305a arranged on the opposite surface, guided along the longitudinal direction of the glass, emitted by the out-coupler 305b through the opposite surface of the glass and recognized by the user's eyes.

[0161] like Figure 5 As illustrated in (f), the glass optical element with an active grating may be provided with an in-coupler 306a and an out-coupler 306b, wherein the in-coupler 306a is formed as an active grating inside the glass on the side where the image light is incident, and the out-coupler 306b is formed as an active grating inside the glass on the side where the image light is emitted.

[0162] Therefore, the image light incident into the glass can be totally reflected by the in-coupler 306a, guided along the longitudinal direction of the glass, emitted to the outside of the glass by the out-coupler 306b, and recognized by the user's eyes.

[0163] According to a modified example, a pin mirror type optical element may be used as the display unit.

[0164] In addition, if Figure 6 As illustrated in (a), the surface reflection type optical element of the free-form combiner type may use a free-form combiner glass formed such that a plurality of flat surfaces with different incident angles of image light are formed in a single piece of glass to have an overall curved surface to perform the role of a combiner. Such a free-form combiner glass 300 may receive image light at different incident angles for each region and emit the image light to a user.

[0165] like Figure 6 As illustrated in (b), a flat HOE type surface reflection type optical element may be provided with a HOE 311 applied or patterned on the surface of a flat piece of glass, and image light entering from the projection device 200 may pass through the HOE 311, may be reflected from the surface of the glass and then pass through the HOE 311 again to be emitted toward a user.

[0166] like Figure 6As shown in (c) of FIG. 1 , a free-form HOE type surface reflection type optical element may be provided with a HOE 313 applied or patterned on the surface of a piece of free-form glass, and the operating principle may be the same as Figure 6 The same as described in (b).

[0167] Figure 7 is a perspective view of a projection device according to one embodiment, and Figure 8 is an exploded perspective view of a projection device according to one embodiment.

[0168] Reference Figure 7 and Figure 8 , the projection device 200 according to one embodiment may include an outer lens LS, a lens barrel 210, a housing 220, a light source unit 230, a light guide LG, a lens FL, and an additional housing 240. In addition, the projection device 200 may include a first spacer SP1 and a second spacer SP2.

[0169] First, the outer lens LS may be inserted into the lens barrel 210. That is, the lens barrel 210 is located inside the projection device 200 and may accommodate the outer lens LS. In addition, the lens barrel 210 may accommodate the light guide LG, the lens LF, the first spacer PS1, and the second spacer SP2.

[0170] The lens barrel 210 may have a space for accommodating the above-mentioned components or additional optical elements. For example, the lens barrel 210 may include a first groove and a second groove to be described below. The outer lens LS may be disposed in the first groove. The light guide LG may be disposed in the second groove. In addition, the first groove and the second groove may be spaced apart from each other in the lens barrel 210. That is, the lens barrel 210 has a space (e.g., a groove) in which the outer lens LS and the light guide LG are disposed, and these spaces may be separated or spaced apart from each other. Therefore, the insertion or connection of the outer lens and the light guide may be facilitated.

[0171] On the contrary, when the above-mentioned spaces are connected to each other, miniaturization of the projection device can be achieved.

[0172] The outer lens LS may be accommodated in the lens barrel 210, and the first spacer SP1 may be located outside the outer lens LS. The first spacer SP1 may be disposed outside the outer lens LS accommodated in the first groove of the lens barrel 210 to prevent the outer lens LS from being separated.

[0173] The lens barrel 210 may include a plurality of holes connected to the second groove. The plurality of holes may be located on the side surface of the lens barrel 210. Therefore, the light emitted from the light source unit 230 described below may be incident on the light guide LG. In addition, the light incident on the light guide LG may be reflected and passed through or transmitted through the outer lens LS to be provided to the above-mentioned waveguide. For this purpose, the first groove and the second groove may be connected to each other through a through hole. That is, the light reflected from the light guide LG in the second groove may be provided to the outer lens LS of the first groove through the through hole. In addition, as described above, the light from the light source unit 230 may be emitted to the internal light guide LG through the plurality of holes provided on the side surface of the lens barrel 210.

[0174] The light guide LG may be located in the lens barrel 210. The light guide LG may be connected to a lens FL which will be described below.

[0175] The light guide LG may include at least one prism. For example, the light guide LG may be formed by connecting or combining a plurality of prisms. The light guide LG may include a prism. The prism is a reflective member, which may include, for example, an x-prism. As an example, the light guide LG may have a structure in which at least two prisms are connected. In addition, the light guide LG may be a non-polarized prism. That is, the light guide LG may not perform polarization on the light emitted from the light sources 232a, 232b, and 232c.

[0176] The light guide LG may include at least two coated surfaces (reflective members or reflective sheets). One of the at least two coated surfaces may reflect light having a first wavelength and light having a second wavelength, and transmit light having a third wavelength. That is, the coated surface may reflect light in a specific wavelength band. Therefore, for light emitted from the plurality of light sources 232a, 232b, and 232c, light in a desired wavelength band may be reflected from the light guide LG. For example, light passing through the light guide LG may be provided to the outer lens LS.

[0177] The lens FL may be connected to the light guide LG. The lens FL may be disposed adjacent to the light guide LG. For example, the lens FL may be in contact with the light guide. That is, the lens FL may be in contact with the light guide LG. In addition, the light guide LG may be in contact with the lens FL.

[0178] The lens FL may be coupled with the light guide LG. In this case, the lens FL may be coupled to the light guide LG by an adhesive member or a coupling member. The adhesive member or the coupling member may be located between the lens FL and the light guide LG.

[0179] The lens FL is located on the outer surface of the light guide LG, and there may be at least one lens FL. For example, the number of lenses FL may correspond to the number of light sources of the light source unit 230 to be described below. When the number of light sources is three, the number of lenses FL may also be three.

[0180] For example, the lens FL may include a first lens, a second lens, and a third lens corresponding to the light source. The first lens may correspond to the first light source unit. The second lens may correspond to the second light source unit. The third lens may correspond to the third light source unit. That is, the first lens to the third lens may receive light emitted from the first light source unit to the third light source unit, respectively.

[0181] The second spacer SP2 may be located in the lens barrel 210. For example, the second spacer SP2 may be larger than the light guide LG or the lens FL. The second spacer SP2 may be disposed outside the light guide LG and the lens FL. Therefore, the light guide LG and the lens FL may not be separated from the lens barrel 210. In other words, the second spacer SP2 may prevent the light guide LG and the lens FL from being separated from the lens barrel 210.

[0182] The housing 220 may be located outside the lens barrel 210. The housing 220 may surround the lens barrel 210. For example, the housing 220 may be arranged to surround at least a portion of the lens barrel 210. In addition, the housing 220 may include a space for accommodating a light source. In addition, the housing 220 may include at least one housing hole. The light source may be arranged in the housing hole. In addition, light emitted from the light source may be provided to the lens FL and the light guide LG through at least one housing hole. The housing 220 may be arranged outside the lens barrel 210 and include a space for accommodating the lens barrel 210 and the light source unit 230.

[0183] The light source unit 230 may be provided as one or more light source units. Similar to the above description, the following description is based on three light source units. The light source unit 230 may include a first light source unit 230a, a second light source unit 230b, and a third light source unit 230c.

[0184] The first light source unit 230a may overlap with the outer lens LS in the second direction (Y-axis direction). The second direction (Y-axis direction) may correspond to the direction of light emitted from the projection device 200. That is, the second direction (Y-axis direction) may correspond to the direction in which light emitted from the light source device 230 is reflected from the light guide LG and emitted to the above-mentioned display unit.

[0185] The second light source unit 230b and the third light source unit 230c may be positioned to face each other. Alternatively, the second light source unit 230b and the third light source unit 230c may be positioned opposite to each other.

[0186] The second light source unit 230b and the third light source unit 230c may overlap in the first direction (X-axis direction). The first direction (X-axis direction) may be perpendicular to the second direction (Y-axis direction). The third direction (Z-axis direction) may be perpendicular to the first direction and the second direction.

[0187] The first light source unit 230a may be located in a region between the second light source unit 230b and the third light source unit 230c. A direction of light emitted from the second light source unit 230b and a direction of light emitted from the third light source unit 230c may be opposite to each other.

[0188] The light source unit may include substrates 231 a , 231 b , and 231 c , light sources 232 a , 232 b , and 232 c , and optical elements 233 a , 233 b , and 233 c .

[0189] In addition, substrates 231a, 231b, and 231c, light sources 232a, 232b, and 232c, and optical elements 233a, 233b, and 233c may be sequentially located inside the housing 220. That is, the optical element may be located closer to the light guide LG than the substrate and the light source.

[0190] The substrates 231 a , 231 b , and 231 c may be connected to the light sources 232 a , 232 b , and 232 c and transmit power so that the light sources 232 a , 232 b , and 232 c emit light.

[0191] The substrates 231 a , 231 b , and 231 c may be located at the outermost side of the housing 220 .

[0192] The substrates 231a, 231b, and 231c may include a first substrate 231a, a second substrate 231b, and a third substrate 231c. The first substrate 231a may overlap with the light guide LG in the second direction (Y-axis direction). The second substrate 231b and the third substrate 231c may overlap in the first direction (X-axis direction). The second substrate 231b and the third substrate 231c may be positioned in the housing 220 to face each other. The first substrate 231a may be located in a region between the second substrate 231b and the third substrate 231c.

[0193] The light sources 232a, 232b, and 232c may emit light. For example, the light emitted from the light sources 232a, 232b, and 232c may be incident on the light guide LG in the housing 220. The light guide LG may be located in the housing 220.

[0194] There may be one or more light sources 232a, 232b, and 232c. The light sources 232a, 232b, and 232c may include a first light source 232a, a second light source 232b, and a third light source 232c. The light sources 232a, 232b, and 232c may be disposed on a substrate.

[0195] That is, the light sources 232a, 232b and 232c of the light source device 230 can be set as a single light source or a plurality of light sources. For example, the plurality of light sources 232a, 232b and 232c can include a first light source 232a, a second light source 232b and a third light source 232c. The first light source 232a to the third light source 232c can emit light in the same direction or in different directions. For example, the second light source 232b and the third light source 232c can be positioned to face each other. The second light source 232b and the third light source 232c can be positioned to overlap in the first direction (X-axis direction). The light guide LG can be located between the second light source 232b and the third light source 232c. Therefore, the light guide LG can overlap with the second light source 232b and the third light source 232c.

[0196] The first to third light sources 232a to 232c may emit light toward the light guide LG. The first light source 232a may overlap with the light guide LG in the second direction. With this configuration, the projection device 200 may have a compact light source device 230.

[0197] In addition, the first light source 232a, the second light source 232b and the third light source 232c may emit light having the same wavelength or color or different wavelengths or colors. For example, the first light source 232a, the second light source 232b and the third light source 232c may emit red light, green light and blue light, respectively.

[0198] The number of optical elements 233a, 233b and 233c can be one or more. Optical elements 233a, 233b and 233c can include first optical element 233a, second optical element 233b and third optical element 233c corresponding to first light source 232a, second light source 232b and third light source 232c, respectively. First optical element 233a, second optical element 233b and third optical element 233c can include optical filter. In addition, first optical element 233a, second optical element 233b and third optical element 233c can include glass. First optical element 233a, second optical element 233b and third optical element 233c can filter light. Alternatively, first optical element 233a, second optical element 233b and third optical element 233c can block foreign matter from entering the light source as early as possible. That is to say, the light source can be protected.

[0199] The additional housing 240 may be disposed outside the lens barrel 210 and surround the lens barrel 210. The lens barrel 210 may be coupled to the housing 220 by various coupling methods, and the additional housing 240 may be coupled to the housing 220. The additional housing 240 may also be coupled to the lens barrel 210. Therefore, the projection device 200 according to the embodiment may provide improved reliability.

[0200] Fig. 9is a view describing coupling of an outer lens, a first spacer, a light guide, a lens, and a second spacer with a lens barrel in a projection device according to one embodiment, Fig.10 is a view describing the coupling between a barrel, a housing, and an additional housing in a projection device according to an embodiment, and Fig.11 is a view describing coupling between a housing and a light source unit in a projection device according to one embodiment.

[0201] Reference Figures 9 to 11 In the projection device according to the embodiment, the sleeve 210 may include the first groove 210h1 and the second groove 210h2 as described above. The first groove 210h1 and the second groove 210h2 may overlap in the second direction (Y-axis direction). In addition, the second groove 210h2 and the first groove 210h1 may be sequentially arranged in the second direction (Y-axis direction).

[0202] The outer lens may be disposed in the first groove 210h1. The light guide may be disposed in the second groove 210h2.

[0203] The first groove 210h1 and the second groove 210h2 may be spaced apart from each other in the second direction (Y-axis direction). In addition, the first groove 210h1 and the second groove 210h2 may be connected to each other through the through hole as described above. Therefore, the light reflected from the light guide in the second groove 210h2 may be provided to the outer lens in the first groove 210h1 and finally emitted to the display unit.

[0204] The outer lens LS may be inserted into the first groove 210h1 of the lens barrel 210. The first spacer SP1 may be located outside the outer lens LS in the first groove 210h1 in the lens barrel 210. As described above, the first spacer SP1 may contact the outer lens LS to prevent the outer lens LS from being separated.

[0205] The light guide LG and the lenses FL1, FL2, and FL3 connected to the light guide LG may be inserted into the second groove 210h2. The light guide LG and the lenses FL1, FL2, and FL3 connected to the light guide LG may be located in the second groove 210h2. The second spacer SP2 may be located outside the light guide LG and the lenses FL1, FL2, and FL3 connected to the light guide LG. The second spacer SP2 may contact the light guide LG or the lens (particularly the first guide lens FL1). Therefore, the separation of the light guide LG and the lenses FL1, FL2, and FL3 connected to the light guide LG may be prevented.

[0206] The first spacer SP1 and the second spacer SP2 may be sequentially disposed in the second direction (Y-axis direction). The first spacer SP1 and the second spacer SP2 may overlap in the second direction (Y-axis direction). The outer lens LS, the light guide LG, and the first guide lens FL1 may be located between the first spacer SP1 and the second spacer SP2. Therefore, the first spacer SP1 and the second spacer SP2 may overlap with the outer lens LS, the light guide LG, and the first guide lens FL1 in the second direction (Y-axis direction).

[0207] The lens barrel 210 can be inserted into the housing 220. That is, the lens barrel 210 can be located in the receiving hole of the housing 220. In addition, the housing 220 and the lens barrel 210 can be connected by various connection methods. For example, the protrusion of the housing 220 and the connection hole of the lens barrel 210 can be connected to each other. In addition, the housing 220 can be located at the bottom of the lens barrel 210, and the additional housing 240 can be located at the top of the lens barrel 210. The improved connection strength between the lens barrel 210 and the housing 220 can be maintained by the additional housing 240.

[0208] After the lens barrel 210 is accommodated in the housing 220, a plurality of light source units may be inserted into the side surface of the housing 220. For example, the first light source unit 230a, the second light source unit 230b, and the third light source unit 230c may be located on the side surface of the housing 220.

[0209] Fig.12 is a view of an optical system of a projection device according to a first embodiment, Fig.13 is a perspective view of a light guide, a fourth lens, and a side lens in a projection device according to an embodiment, and Fig.14 is another perspective view of the light guide, the fourth lens, and the side lenses in the projection device according to the embodiment.

[0210] Reference Figure 12 to Figure 14In the projection device according to the first embodiment, the optical system may include an outer lens LS, a light guide LG, an optical element (not shown), and a lens FL. In addition, in the projection device, the optical system may further include light sources 232a, 232b, and 232c. In addition, in the projection device, the optical system may include an aperture ST. The outer lens LS may be used interchangeably with "lens group" and "at least one lens". In the projection device, the direction from the light guide LG toward the lens group LS, the aperture ST, or the light guide WG may be referred to as the object direction (object side), the projection direction (or projection side), or the target direction (or target side). Therefore, the target side may correspond to the direction from each light source toward the waveguide WG based on the light travel path. The direction from the light guide LG toward each light source may be referred to as the light source direction (source side), the image direction (or image side), or the light source side. That is, the light source side may be in the direction from the light guide LG toward the light source. In the figure, the light source side is the direction toward the first light source, but the light source side may correspond to the direction from the first side lens to the third side lens and the first optical element to the third optical element toward the light source adjacent to these components. For example, the light source side relative to the second side lens or the second optical element corresponds to a direction toward the second light source 232 b .

[0211] Specifically, the lens group LS may include N lenses. The N lenses may include a first lens L1, a second lens L2, a third lens L3, and a fourth lens L4 in order adjacent to the waveguide WG.

[0212] The light guide LG may have a hexahedral shape. Therefore, the light guide LG may include a first side surface or a first side portion LGS1 facing the first light source 232a. The light guide LG may include a second side surface or a second side portion LGS2 facing the second light source 232b. The light guide LG may include a third side surface or a third side portion LGS3 facing the third light source 232c. The light guide LG may include a fourth side surface or a fourth side portion LGS4 facing the fourth lens L4 or the Nth lens Ln. In addition, the first side portion to the fourth side portion may refer to directions other than the side surfaces. For example, the first light source 232a may be located at a first side of the light guide LG.

[0213] In addition, the lenses FL1 to FL3 may include a first side lens FL1, a second side lens FL2, and a third side lens FL3. The first guide lens described above may correspond to the first side lens FL1. In addition, the first side lens may be used interchangeably with "lens", "guide lens", etc.

[0214] The first side portion LGS1 and the fourth side portion LGS4 of the light guide LG may be opposite to or face each other. The second side portion LGS2 and the third side portion LGS3 of the light guide LG2 may be opposite to or face each other.

[0215] In the light guide LG, the first optical axis OP1 of the first side portion LGS1 and the fourth side portion LGS4 may be orthogonal to the second optical axis OP2 of the second side portion LG2 and the third side portion LG3. The first optical axis OP1 may correspond to the axis of the light emitted from the first light source 232a and may be parallel to the second direction (Y-axis direction). The second optical axis OP1 may be parallel to the first direction (X-axis direction). According to this configuration, since the optical axes are orthogonal to each other, the mounting structure of the first light source 232a to the third light source 232c in the projection device according to the embodiment can be miniaturized, and the process can be minimized.

[0216] The lens group LS may include three or four lenses. As shown in FIG. 17 , the outer lens LS may include three lenses, and the three lenses may include first lens L1 to third lens L3. In this case, the N-th lens corresponds to the third lens L3. However, as shown in the figure, the outer lens or lens group LS may include four lenses, and the four lenses may include first lens L1 to fourth lens L4. In this case, the N-th lens Ln corresponds to the fourth lens L4.

[0217] The first lens L1 may be disposed farthest from the fourth side LGS4 of the light guide LG, and the Nth or fourth lens L4 or Ln may be disposed closest to the fourth side LGS4 of the light guide LG.

[0218] The first side portion LGS1 and the fourth side portion LGS4 of the light guide LG may overlap in the optical axis direction or the second direction.

[0219] As an embodiment, the Nth lens or the fourth lens L4 may be coupled with the light guide LG. In particular, the fourth lens L4 may be in contact with a fourth side surface or a fourth side portion LGS4 of the light guide LG.

[0220] The lens FL may be disposed on the light guide LG. For example, the lens FL may be in contact with the light guide LG. The number of lenses FL may correspond to the number of light sources. For example, when the number of light sources is three, the number of lenses FL may be three. In addition, when the number of light sources is one, the number of lenses FL may be one.

[0221] Hereinafter, the lens FL may be referred to as a "light source lens" or a "side lens". The lens FL may include a first side lens FL1, a second side lens FL2, and a third side lens FL3. The first side lens FL1 may be located in a region between the second side lens FL2 and the third side lens FL3. However, the first side lens FL1 may not overlap with the second side lens FL2 and the third side lens FL3 in the second direction (Y-axis direction). The first side lens FL1 may be configured not to be aligned with the second side lens FL2 and the third side lens FL3 in the first direction (X-axis direction). In addition, the first side lens FL1 may overlap with the light guide LG in the second direction (Y-axis direction). For example, the first side lens FL1 may overlap with the light guide LG in the light emission direction of the first light source 232a.

[0222] In addition, an optical element may be disposed between the light source and the light guide LG. The optical element may include a first optical element, a second optical element, and a third optical element. The light source may include a first light source 232a, a second light source 232b, and a third light source 232c.

[0223] The first optical element may be disposed between the first light source 232a and the first side lens FL1. The second optical element may be disposed between the second light source 232b and the second side lens FL2. The third optical element may be disposed between the second light source 232c and the third side lens FL3.

[0224] The first optical element may be disposed between the second optical element and the third optical element. The first optical element may not overlap with the second optical element and the third optical element in the second direction (Y-axis direction). The first optical element may be disposed to be misaligned with the second optical element and the third optical element in the second direction.

[0225] Therefore, the light emitted from the first light source 232a can be provided to the waveguide WG through the first optical element, the first side lens FL1, the light guide LG and the outer lens LS. The light emitted from the second light source 232b can be provided to the waveguide WG through the second optical element, the second side lens FL2, the light guide LG and the outer lens LS. The light emitted from the third light source 232c can be provided to the waveguide WG through the third optical element, the third side lens FL3, the light guide LG and the outer lens LS.

[0226] The first lens L1 may include a first surface S11 or a first target surface S11 as a surface facing the waveguide WG (or a target or an object). In addition, the first lens L1 may include a second surface S12 or a second target surface S22 as a surface facing the light guide LG (or light, a light source, or an image). The second lens L2 may include a third surface S31 or a third target surface S21 as a surface facing the waveguide WG. The second lens L2 may include a fourth surface S22 or a fourth target surface S22 as a surface facing the light guide LG. The third lens L3 may include a fifth surface S31 or a fifth target surface S31 as a surface facing the waveguide WG. The third lens L3 may include a sixth surface S32 or a sixth target surface S32 as a surface facing the light guide LG. The fourth lens L4 may include a seventh surface S41 or a fourth target surface S41 as a surface facing the waveguide WG. The fourth lens L4 may include an eighth surface S42 or an eighth target surface S42 as a surface facing the light guide LG. The fourth surface S42 may be in contact with the fourth side portion LGS4 of the light guide LG. In this way, total reflection can be prevented from occurring on the sides (first to fourth sides) of the light guide. For example, total reflection on the fourth side surface LGS4 of the light guide LG can be suppressed, and thus stray light can be eliminated.

[0227] In addition, the light emitted from the plurality of light sources may be reflected from the light guide and propagate toward the aperture ST or the waveguide WG after passing through the outer lens LS. In the figure, it is shown that the light emitted from the first light source 232a passes through the light guide LG and is provided to the waveguide. However, as described above, it should be understood that the light emitted from the other light sources (the second light source and the third light source) is also reflected from the light guide LG and propagates toward the waveguide, etc.

[0228] Below, various embodiments of the present invention will be described based on the above content. In addition, except for any content that contradicts with the content described in other implementations, the content to be described below can be applied in the same manner.

[0229] In the optical system of the projection device according to the first embodiment, the first light source 232a may be disposed on the first side portion or the image side of the light guide LG. The lens group LS may be disposed on the fourth side portion or the object side (or the projection side or the target side) of the light guide LG. In addition, the first side lens FL1 may be located between the first side portion LGS1 of the light guide LG and the first light source 232a. As an embodiment, the first side portion LGS1 of the light guide LG may overlap with the fourth side portion LGS4 of the light guide LG in the optical axis direction of the outer lens LS or in the second direction (Y-axis direction). In other words, the first side portion LGS1 and the fourth side portion LGS4 of the light guide LG may overlap and face each other in the second direction.

[0230] In the present embodiment, the first side lens FL1 may be in contact with the light guide LG. For example, the first side lens FL1 may be bonded to the first side portion LGS1 of the light guide LG by an adhesive member or the like, or may be integrally formed with the first side portion LGS1.

[0231] As described above, the lens group LS may include the first lens L1 to the N-th lens Ln. As an embodiment, in the lens group LS, the first lens L1 may be disposed farthest from the fourth side portion LGS4 of the light guide LG. The fourth lens L4 may be disposed closest to the fourth side portion LGS4 of the light guide LG. In other words, the length between the fourth side portion LGS4 and the first lens L1 in the second direction (Y-axis direction) may be greater than the length d4 between the fourth side portion LGS4 and the fourth lens L4 in the second direction (Y-axis direction). In this case, since the fourth lens L4 is in contact with the fourth side portion LGS4, the length d4 may be 0.

[0232] In addition, third lens L3 and second lens L2 may be disposed between first lens L1 and fourth lens L4 in the second direction.

[0233] As an embodiment, in the first lens L1, a surface opposite to a surface of the fourth side portion LGS4 facing the light guide LG may be convex. That is, the first lens L1 may be convex in the second direction (Y-axis direction). On the contrary, the first lens L1 may be concave in a direction opposite to the second direction. In other words, the first surface S11 of the first lens L1 may be concave toward the fourth side portion LGS4. The first lens L1 may be convex toward the waveguide WG. Therefore, the light collected from the light guide LG may be easily guided to the light guide plate or the waveguide WG. In other words, the collected light may be effectively diffused.

[0234] As an embodiment, the second side lens FL2 may be located between the second side portion LGS2 of the light guide LG and the second light source 232b. In addition, the third side lens FL3 may be located between the third side portion LGS3 of the light guide LG and the third light source 232c.

[0235] The first side lens FL1 may include a surface FL12 adjacent to the first light source 232a or an image-side surface. The image-side surface FL12 of the first side lens FL1 may be convex toward the first light source 232a or the image side.

[0236] The second side lens FL2 may include a surface FL22 adjacent to the second light source 232b or an image-side surface. The image-side surface FL22 of the second side lens FL2 may be convex toward the second light source 232b or the image side.

[0237] The third side lens FL3 may include a surface FL32 adjacent to the third light source 232c or an image-side surface. The image-side surface FL32 of the third side lens FL3 may be convex toward the third light source 232c or the image side.

[0238] In other words, the surface FL12 adjacent to the first light source of the first side lens FL1 may bulge toward the first light source 232a. The surface FL22 adjacent to the second light source of the second side lens FL2 may bulge toward the second light source 232b. The surface FL32 adjacent to the third light source of the third side lens FL3 may bulge toward the third light source 232c.

[0239] In the first, second and third side lenses FL1, FL2 and FL3, surfaces FL12, FL22 and FL32 adjacent to the light sources 232a, 232b and 232c may have the same curvature radius. The curvature radius of each of the above surfaces FL12, FL22 and FL32 may have a negative (-) value.

[0240] By this configuration, the total track length (TTL) can be minimized and manufacturing yield can be easily ensured. The TTL may correspond to the distance from the first surface S11 of the first lens L1 to the light source 232a, 232b or 232c on the optical axis. Alternatively, the TTL may correspond to the distance from the first surface S11 of the first lens L1 to the light source along the optical axis. For example, the TTL may correspond to the distance from the first lens L1 to the first light source 232a on the optical axis. The distance from the first lens L1 to the first light source 232a or the TTL on the optical axis may be less than or equal to twice the focal length of the optical system including the lens group Ls, the light guide LG and the side lens FL1, FL2 or FL3. By this configuration, the size of the projection device or the optical system can be easily reduced.

[0241] According to an embodiment, the focal length of the optical system (or lens group Ls, light guide LG and side lens FL1, FL2 or FL3) may be in the range of 4 mm to 10 mm. The maximum distance from the first lens L1 to the first light source 232a or TTL may be in the range of 8 mm to 20 mm.

[0242] In addition, in the first lens L1, the surface facing the light guide LG or the second surface S12 may be convex in the direction opposite to the direction toward the light guide LG. That is, the second surface S12 may be convex toward the object side, the target side, or the projection side. With this configuration, TTL can be minimized, and the brightness of light provided to the waveguide WG can be easily ensured.

[0243] In addition, the size of the light guide LG may be larger than the size of the light source. For example, the area S1 of each side portion of the light guide LG may be larger than the area of ​​each of the light sources 232a to 232c. For example, the area of ​​each surface of the light guide LG facing each of the light sources 232a to 232c is larger than the area of ​​each of the light sources 232a to 232c facing the light guide LG. For example, the area of ​​the first side surface LGS1 of the light guide LG is larger than the area of ​​the first light source 232a. The area of ​​the second side surface LGS2 of the light guide is larger than the area of ​​the second light source 232b. The area of ​​the third side surface LGS3 of the light guide is larger than the area of ​​the third light source 232c. For example, the minimum length of the light guide LG in one direction may be larger than the minimum length of the light source in one direction. For example, the minimum length of the first side surface LGS1 of the light guide in one direction is larger than the minimum length of the first light source 232a in one direction. The minimum length of the second side surface LGS2 of the light guide in one direction is larger than the minimum length of the second light source 232b in one direction. The minimum length of the third side surface LGS3 of the light guide in one direction is greater than the minimum length of the third light source 232c in one direction. Therefore, the efficiency of the light source can be improved and the occurrence of flare can be prevented.

[0244] The size or area S1 of each side of the light guide LG may be larger than the size S2 of each side lens in contact with each side. For example, the size S2 of the first side lens FL1 may be smaller than the size S1 of the first side LGS1 of the light guide. For example, the size or effective diameter of the surface FL11 of the first side lens FL1 adjacent to the light guide is smaller than the size of the first side surface LGS1 of the light guide. The size or effective diameter of the surface FL21 of the second side lens FL2 adjacent to the light guide is smaller than the size of the second side surface LGS2 of the light guide. The size or effective diameter of the surface FL31 of the third side lens FL3 adjacent to the light guide is smaller than the size of the third side surface LGS3 of the light guide. For example, the minimum length of the light guide LG in one direction is greater than the minimum length of each of the first to third side lenses in one direction. For example, the minimum length of the first side surface LGS1 of the light guide in one direction is greater than the minimum length or diameter length of the surface FL11 of the first side lens FL1 adjacent to the light guide in one direction. The minimum length of the second side surface LGS2 of the light guide in one direction is greater than the minimum length or diameter length of the surface FL12 of the second side lens FL2 adjacent to the light guide in one direction. The minimum length of the third side surface LGS3 of the light guide in one direction is greater than the minimum length or diameter length of the surface FL13 of the third side lens FL3 adjacent to the light guide in one direction. Through this configuration, the interference between the side lens FL and the light guide LG can be eliminated, and the ease of manufacturing the side lens can be ensured.

[0245] In addition, the size or effective diameter of the light guide LG can be larger than the size or effective diameter of at least one of the first to Nth lenses (Ln or fourth lens) of the lens group Ls. Through this configuration, TTL reduction can be ensured and miniaturization of the projection device can be achieved.

[0246] In addition, the size S4 of the Nth or fourth lens L4 may be different from the size S3 of the fourth side portion LGS4 of the light guide LG. For example, the size S4 of the Nth or fourth lens L4 may be smaller than the size S3 of the fourth side portion LGS4 of the light guide LG. Therefore, the above-mentioned miniaturization can be achieved.

[0247] As a modified example, size S4 of the Nth or fourth lens L4 may be smaller than size S3 of the fourth side LGS4 of the light guide LG. Alternatively, some areas of the fourth lens L4 may be misaligned with the fourth side LGS4 of the light guide LG in the second direction (Y-axis direction).

[0248] In addition, an object-side surface F11 of the first side lens FL1 may be in contact with the first side portion LGS1 of the light guide LG. An object-side surface F21 of the second side lens FL2 may be in contact with the second side portion LGS2 of the light guide LG. An object-side surface F31 of the third side lens FL3 may be in contact with the third side portion LGS3 of the light guide LG. In addition, an image-side surface or eighth surface S42 of the Nth or fourth lens L4 may be in contact with the fourth side portion LGS4 of the light guide LG.

[0249] A seventh surface S43 of the fourth lens L4 may be concave toward the light guide LG or convex toward the object side.

[0250] The fifth surface S31 may be concave in the second direction. Alternatively, the fifth surface S31 may be convex toward the light guide LG. The sixth surface S32 may be concave in the second direction or concave toward the waveguide. The sixth surface S32 may be concave (or convex) in the second direction or concave (or convex) toward the waveguide. Alternatively, the sixth surface S32 may be convex (or concave) toward the light guide LG.

[0251] The third surface S21 may protrude in the second direction or protrude toward the waveguide. Alternatively, the third surface S3 may be concave toward the light guide LG. The fourth surface S22 may protrude (or concave) in the second direction or protrude (or concave) toward the waveguide. Alternatively, the fourth surface S22 may protrude (or concave) toward the light guide LG.

[0252] The first surface S11 may be convex toward the waveguide or the first direction as described above. Alternatively, the second surface S12 may be concave (or convex) toward the light guide LG. The second surface S12 may be concave in the first direction or concave toward the waveguide.

[0253] In addition, in an embodiment, the refractive power or power of the first lens L1 may be positive. The power of the combination of lenses disposed between the first lens L1 and the Nth lens Ln may be positive or negative. That is, the power of the combination of the second lens L2 and the third lens L3 may be positive or negative.

[0254] The second lens L2 may have positive refractive power. The third lens may have negative refractive power. The fourth lens may have positive refractive power or negative refractive power. The side lenses FL1 to FL3 may have positive refractive power.

[0255] The second side LGS2 of the light guide LG may be disposed to face the third side LGS3 of the light guide LG with the light guide LG interposed therebetween. Therefore, the second and third side lenses FL2 and FL3 may be disposed to face each other or symmetrically with respect to the light guide LG.

[0256] As described above, each side lens may be in contact with the light guide LG. For example, the first side lens FL1 may be in contact with or abut against the light guide LG. The second side lens FL2 may be in contact with or abut against the light guide LG. In addition, the third side lens FL3 may be in contact with or abut against the light guide LG.

[0257] Each side lens may have a curvature radius of 100 mm or more with respect to an optical axis of a surface or contact surface FL11, FL21, or FL31 adjacent to the light guide LG. The optical axis may correspond to a central axis of light emitted from each light source to the light guide.

[0258] In addition, the curvature radius of the seventh surface S41 of the Nth lens or the fourth lens L4 may have a positive value or a negative value. For example, as described above, the seventh surface S41 may be convex or concave in the second direction or convex or concave toward the object side.

[0259] With this configuration, the field of view (FOV) of light provided from the projection device or the optical system can be maintained at a narrow angle of 45 degrees or less.

[0260] In addition, as described above, each side lens may be coupled to the light guide LG by a contact member or a bonding member. The bonding member may be made of a transparent material and have a refractive index similar to that of the light guide LG or the side lens. That is, the bonding member may be located between the light guide LG and one of the first to third side lenses FL1 to FL3. In addition, the bonding member may be located between the light guide LG and the fourth lens L4.

[0261] As described above, the size or length of the side surface of the light guide LG may be greater than or equal to the size or length of the surface of each side lens adjacent to the light guide LG. In this case, even when the size of the side surface of the light guide LG is different from the size of the bonding surface FL11, FL21, or FL31 to which each side lens is bonded to the light guide, the length of the side surface of the light guide LG in one direction (the first direction, the second direction, or the third direction) is greater than the length of the bonding surface FL11, FL21, or FL31 to which each side lens is bonded to the light guide. For example, the length of the side surface of the light guide LG in one direction (the first direction, the second direction, or the third direction) is greater than the length of the side lens (each of the first to third side lenses) in one direction (the first direction, the second direction, or the third direction). For example, the length of the side surface of the light guide LG in two directions may be greater than the length of the bonding surface of the side lens in two directions. In addition, the length of the side surface of the light guide LG in one direction is greater than the length of the bonding surface of the lens in one direction.

[0262] As a modified example, the length of the side surface of the light guide LG in one direction (the first direction, the second direction, or the third direction) may be smaller than the length of the side lens (each of the first to third side lenses) in one direction (the first direction, the second direction, or the third direction). For example, the length of the side surface of the light guide LG in two directions may be greater than the length of the bonding surface of the side lens in two directions, and the length of the side surface of the light guide LG in the remaining one direction may be smaller than the length of the bonding surface of the lens in one direction.

[0263] In addition, as an embodiment, the surface of the side lens adjacent to the light guide LG or the bonding surface F11, F21, F31 and S42 of the side lens may be flat. For example, in the first side lens FL1, the surface adjacent to the light guide LG or the bonding surface F11 may be flat.

[0264] Furthermore, the semi-aperture may have a radius of the effective diameter or a radius of the beam range.

[0265] As described above, the waveguide WG may be disposed to face the first lens L1. That is, the waveguide WG may be positioned adjacent to the first lens L1. The aperture ST may be located in a direction from the first lens L1 toward the waveguide. The aperture ST may be positioned adjacent to the first lens L1. The aperture ST may be positioned to correspond to a contact point between the projection device and the waveguide WG.

[0266] In addition, as an embodiment, in at least one lens among the N lenses, a surface (object-side surface) opposite to a surface facing the light guide may be concave toward the light guide LG.

[0267] The length of the N lenses in the second direction (Y-axis direction) may be smaller than the length of the light guide LG in the second direction.

[0268] In addition, the contents of the following Table 1 can be applied to the components of the optical system according to the embodiment.

[0269] [Table 1]

[0270]

[0271]

[0272] Here, the left column of each lens discloses the content of the side facing the waveguide, and the right column of each lens discloses the content of the side facing the light source. The left column of the side lens discloses the content of the surface F11, F21 or F31 facing the light guide, and the right column of the side lens discloses the content of the surface F12, F22 or F32 facing the light source. The thickness of each lens corresponds to the left column. The spacing between adjacent lenses corresponds to the right column. The right column of thickness represents the spacing with the adjacent member in the direction toward the light source. For example, the content of the first surface of the first lens is disclosed in the left column. The content of the second surface of the first lens is disclosed in the right column. In addition, the unit of length, such as thickness, can be mm. Fig.15 is a view of an optical system of a projection device according to a second embodiment.

[0273] Reference Fig.15 The projection device according to the second embodiment may include the optical system as described above. In particular, the optical system in this embodiment may include the aperture ST, the outer lens LS, the light guide LG, the side lens FL1, the optical element 233a and the light source 232a as described in the first embodiment. Except for the contents to be described below, the above contents may be applied in the same manner.

[0274] However, in the present embodiment, there is only one light source, and the optical system may include a first light source 232a. The optical system may include a first optical element 233b and a first side lens FL1. Therefore, the description of the second optical element, the third optical element, the second side lens, the third side lens, the second light source, and the third light source described above may not be applied to the present embodiment.

[0275] In an embodiment, the light source includes only the first light source, and may include light sources having various colors or wavelength bands. The first light source may include an RGB light source, such as an RGB LED. Alternatively, the first light source may include a monochromatic light source LED that outputs any one color of RGB. Alternatively, the first light source may include a light source LED that outputs two colors of RGB.

[0276] In addition, the contents of the following Table 2 can be applied to the components of the optical system according to the present embodiment.

[0277] [Table 2]

[0278]

[0279]

[0280]

[0281] Here, the left column of each lens discloses the content of the side facing the waveguide, and the right column of each lens discloses the content of the side facing the light source. The left column of the side lens discloses the content of the surface F11, F21 or F31 facing the light guide, and the right column of the side lens discloses the content of the surface F12, F22 or F32 facing the light source. The thickness of each lens corresponds to the left column. The spacing between adjacent lenses corresponds to the right column. For example, the content of the first surface of the first lens is disclosed in the left column. The content of the second surface of the first lens is disclosed in the right column. In addition, the left column of the light guide (side lens or optical element) discloses the content of the side facing the waveguide. The right column of the light guide (side lens or optical element) discloses the content of the side facing each light source (for example, the second light source for the second side lens). In addition, with respect to the thickness of the light guide (side lens or optical element), the left column represents the thickness of the component (the length in the first direction or along the optical axis), and the right column represents the spacing distance between the component and the nearest component toward the light source in the first direction. This description can be applied as in the description of Table 1.

Claims

1. A projection device, comprising: Light guide; a first light source disposed on a first side of the light guide; a lens group, the lens group being arranged on a fourth side portion of the light guide; as well as a first side lens disposed between the first side portion of the light guide and the first light source, Wherein, the lens group includes the first lens to the Nth lens, the first lens being arranged farthest from the fourth side of the light guide, The first side portion of the light guide overlaps with the fourth side portion of the light guide in the optical axis direction of the lens group, and The first side lens and the Nth lens are in contact with the light guide.

2. The projection device according to claim 1, wherein: The Nth lens in the lens group is disposed closest to the light guide.

3. The projection device according to claim 1, further comprising: a second light source disposed on a second side of the light guide; a third light source, the third light source being disposed on a third side of the light guide; a second side lens disposed between the second side portion of the light guide and the second light source; as well as A third side lens is disposed between the third side portion of the light guide and the third light source.

4. The projection device according to claim 3, wherein: A surface of the first side lens adjacent to the first light source is convex, A surface of the second side lens adjacent to the second light source is convex, A surface of the third side lens adjacent to the third light source is convex, and Surfaces of the first side lens, the second side lens, and the third side lens adjacent to each light source have the same radius of curvature.

5. The projection device according to claim 3, wherein: A first optical axis of the first and fourth sides of the light guide is orthogonal to a second optical axis of the second and third sides of the light guide.

6. The projection device according to claim 1, wherein: A distance on an optical axis from the first lens to the first light source is less than or equal to twice the focal lengths of the lens group, the light guide, and the first side lens.

7. The projection device according to claim 1, wherein: A surface of the first lens facing the light guide is convex in a direction opposite to a direction toward the light guide.

8. The projection device according to claim 1, wherein: The size of the light guide is larger than the size of the light source.

9. The projection device according to claim 1, wherein: The first side lens has a size smaller than a size of the first side portion of the light guide.

10. The projection device according to claim 1, wherein: The size or effective diameter of the light guide is larger than the size or effective diameter of at least one lens among the first to Nth lenses of the lens group.

Images