Lighting apparatus, lighting control system, and method of controlling the lighting apparatus

A lighting apparatus connected to a network includes a light source for emitting light. A controller controls operation of the light source in response to an external control signal. A non-contact sensor detects a non-contact signal and generates a reset signal in response to detecting the non-contact signal. A communication interface communicatively connects the lighting apparatus to a wireless network to receive the external control signal from a remote apparatus via the wireless network and disconnects the lighting apparatus from the wireless network in response to receiving the reset signal from the non-contact sensor.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims the benefit of Korean Patent Application No. 10-2013-0096130, filed on Aug. 13, 2013 in the Korean Intellectual Property Office, the disclosure of which is incorporated herein in its entirety by reference.

BACKGROUND

The inventive concept relates to a lighting apparatus, a lighting control system, and a method of controlling the lighting apparatus. More particularly, the inventive concept relates to a lighting apparatus that is communicatively connected to a network and is controlled via communication through the network with an external apparatus, to a lighting control system including the lighting apparatus, and to a method of controlling a connection between the lighting apparatus and the network.

A light emitting diode (LED) having low power consumption and high light efficiency can be used as a light source to replace an incandescent electric lamp or a fluorescent lamp. The LED is additionally compatible with many light emitting controls, and can be used in a wide variety of applications. As such, the LED can be used in conjunction with systems configured for easily controlling lighting apparatuses inside and outside buildings based on wireless network communication have been actively conducted. Such control system can be used to provide different light outputs by controlling light color, light temperature, and light output.

SUMMARY

The inventive concept provides a lighting apparatus that is easily connected to and disconnected from a wireless network and a lighting control system including the lighting apparatus.

The inventive concept also provides a method of controlling a lighting apparatus that is easily connected to and disconnected from a wireless network.

According to an aspect of the inventive concept, there is provided a lighting apparatus including a light source, a controller, a non-contact sensor, and a communication interface. The light source is configured to emit light. The controller is configured to control operation of the light source in response to an external control signal. The non-contact sensor is configured to detect a non-contact signal and to generate a reset signal in response to the non-contact signal. The communication interface is configured to communicatively connect the lighting apparatus to a wireless network to receive the external control signal from a remote apparatus via the wireless network and to disconnect the lighting apparatus from the wireless network in response to receiving the reset signal from the non-contact sensor.

The non-contact sensor may include at least one of a Hall sensor, a proximity sensor, or a magnetic resistance sensor.

The non-contact sensor may detect an approach of a magnetic substance to the lighting apparatus as the non-contact signal.

The communication interface may include an interface unit configured to communicate with the external apparatus via the wireless network by using a predetermined communication protocol, a network setting unit configured to control the interface unit to connect to or disconnect from the wireless network, and a memory configured to store network data related to the wireless network. The network setting unit may delete the network data related to the wireless network stored in the memory in response to receiving the reset signal from the non-contact sensor and controls the interface unit to search for a new network.

The non-contact sensor may generate a first reset signal when a polarity of the approaching magnetic substance is an N electrode, and generate a second reset signal different from the first reset signal when the polarity of the approaching magnetic substance is an S electrode.

The communication interface may disconnect the lighting apparatus from the wireless network and operates in a first reset mode to reconnect the lighting apparatus to the wireless network in response to receiving the first reset signal from the non-contact sensor, and disconnect the lighting apparatus from the wireless network and operates in a second reset mode to connect the lighting apparatus to another wireless network in response to receiving the second reset signal from the non-contact sensor.

The controller may turn the light source on/off or change at least one of a color temperature, chroma, or brightness of the light emitted from the light source in response to the external control signal.

The light source may include a circuit substrate and one or more light emitting devices or one or more light emitting device packages that are disposed on the circuit substrate, wherein the one or more light emitting devices include a first conductive semiconductor layer, an active layer, a second conductive semiconductor layer, a second electrode layer, an insulating layer, a first electrode layer, and a substrate that are sequentially stacked, wherein the first electrode layer includes one or more contact holes that are electrically insulated from the second conductive semiconductor layer and the active layer and that extend from a surface of the first electrode layer to a portion of the first conductive semiconductor layer in order to be electrically connected to the first conductive semiconductor layer, wherein the number of vias is 3 or more, distances between the vias have a matrix structure having rows and columns in a range from about 100 μm to about 500 μm, and depths of the vias are in a range from about 0.5 μm to about 5.0 μm, and wherein the one or more light emitting device packages include a phosphor layer on top surfaces of the one or more light emitting devices and generate a variety of white light having a color temperature in a range from 1500° K to 20000° K.

The one or more light emitting devices may include nano light emitting structures.

The wireless network may operate according to a ZigBee protocol.

According to another aspect of the inventive concept, there is provided a lighting control system including a lighting apparatus, a lighting controller, and a relay. The controller is configured to generate the external control signal. The relay is configured to receive the external control signal from the lighting controller and provide the external control signal to the lighting apparatus.

The lighting apparatus and the relay may transmit or receive a signal between each other using a same wireless communication protocol, and the lighting controller and the relay transmit or receive a signal between each other using a same wireless communication protocol or wired communication protocol.

According to another aspect of the inventive concept, there is provided a method of controlling a lighting apparatus connected to a network. The method includes detecting that a non-contact signal is generated outside of the lighting apparatus. A reset signal is generated in response to detecting the non-contact signal. The lighting apparatus is then disconnected from the network in response to generating the reset signal.

The generating of the reset signal may include: selectively generating a first reset signal or a second reset signal as the reset signal dependent on a type or pattern of the non-contact signal; and reconnecting the lighting apparatus to the network in response to generating the first reset signal and connecting the lighting apparatus to another network in response to generating the second reset signal.

The non-contact signal may be a magnetic signal.

According to another aspect of the inventive concept, a lighting control system includes a lighting apparatus and a lighting controller. The lighting apparatus is configured to emit light in response to a lighting control signal, and to receive the lighting control signal via a communication connection to a wireless network. The lighting controller is spaced apart from the lighting apparatus, and is configured to generate the lighting control signal and to transmit the lighting control signal across the wireless network. The lighting apparatus comprises a non-contact sensor configured to detect a non-contact signal, and the lighting apparatus is configured to disconnect from the wireless network in response to the non-contact sensor detecting a non-contact signal.

The lighting control system may further include a relay communicatively connected to the lighting apparatus via the wireless network and to the lighting controller, and configured to receive the lighting control signal from the lighting controller and to relay the received lighting control signal across the wireless network to the lighting apparatus.

The non-contract sensor may be configured to detect a change in a magnetic field, and to trigger the lighting apparatus to disconnect from the network in response to detecting the change in the magnetic field.

The lighting apparatus may be configured to connect to another wireless network in response to disconnecting from the wireless network, and to emit light in response to another lighting control signal received via the other wireless network.

The lighting apparatus may alternatively or additionally be configured to automatically search for one or more wireless networks to connect to in response to disconnecting from the wireless network.

DETAILED DESCRIPTION

The inventive concept will now be described more fully with reference to the accompanying drawings, in which exemplary embodiments of the inventive concept are shown. The inventive concept may, however, be embodied in many different forms, and should not be construed as being limited to the embodiments set forth herein. Thus, the invention may include all revisions, equivalents, or substitutions which are included in the concept and the technical scope related to the inventive concept. Like reference numerals in the drawings denote like elements. In the drawings, the dimension of structures may be exaggerated for clarity.

Furthermore, all examples and conditional language recited herein are to be construed as being without limitation to such specifically recited examples and conditions. Throughout the specification, a singular form may include plural forms, unless there is a particular description contrary thereto. Also, terms such as “comprise” or “comprising” are used to specify existence of a recited form, a number, a process, an operation, a component, and/or groups thereof, not excluding the existence of one or more other recited forms, one or more other numbers, one or more other processes, one or more other operations, one or more other components, and/or groups thereof.

Unless expressly described otherwise, all terms including descriptive or technical terms which are used herein should be construed as having meanings that are obvious to one of ordinary skill in the art. Also, terms that are defined in a general dictionary and that are used in the following description should be construed as having meanings that are equivalent to meanings used in the related description, and unless expressly described otherwise herein, the terms should not be construed as being ideal or excessively formal.

As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items. Expressions such as “at least one of,” when preceding a list of elements, modify the entire list of elements and do not only modify the individual elements of the list.

FIG. 1is a block diagram of a lighting control system1000according to an embodiment of the inventive concept. Referring toFIG. 1, the lighting control system1000includes a lighting controller300for generating a control message used to control lighting, and a lighting apparatus100for generating lighting according to the control message. The lighting control system1000may further include a relay200for communicatively connecting and relaying messages between the lighting controller300and the lighting apparatus100.

When the lighting control system1000includes the relay200, the lighting apparatus100and the relay200may be communicatively connected to each other through a first network, and the relay200and the lighting controller300may be communicatively connected to each other through a second network. The first and second networks may be the Internet, mobile communication networks, local area networks (LANs), or the like. The first and second networks may be homogeneous or heterogeneous networks, or interconnections of two or more networks.

The lighting apparatus100, the relay200, and the lighting controller300may connect to the first and second networks via various wired or wireless communication links, and may use wireless communication technologies such as WiFi, Bluetooth, ZigBee, or the like. When the lighting control system1000is located at least in part inside of a building, such as a house, office, factory, or the like, communication between the relay200and the lighting apparatus100or communication between the lighting controller300and the lighting apparatus100may be based on a ZigBee protocol. ZigBee is an Institute of Electrical and Electronics Engineers (IEEE) 802.15.4 based low power wireless short distance communication protocol which may be used to transmit data at a speed of 20 Kbps-250 Kbps at a short distance of 1 m-100 m. ZigBee has low power consumption and small program size, and is thus amenable to device miniaturization and has low implementation cost. Fast communication is not required to control the lighting apparatus100, and thus communication technologies like ZigBee that are capable of low power and miniaturization while being limited to short distances and low speed may be used.

The lighting controller300may be spatially spaced apart from the lighting apparatus100and may control the turning on/off of the lighting apparatus100or the adjustment of lighting attributes, for example color, brightness, chroma, color temperature, a dimming period, or the like, via wireless or wired communication. The lighting controller300may be a portable terminal or a lighting control terminal such as a cellular phone, a smart phone, a notebook, a digital broadcasting terminal, a personal digital assistant (PDA), a portable multimedia player (PMP), a navigation system, and a remote control device.

The lighting controller300may generate a control message, for example a control signal, or data used to control the lighting apparatus100according to a previously set program (e.g., a program stored in a memory of the lighting controller300) or a user signal input through an input unit such as a keypad, a touch pad, or the like. The lighting controller300may provide the control signal or the data to the lighting apparatus100or receive information regarding a state of the lighting apparatus100by communicating with the relay200.

The lighting controller300may include a mobile communication module, a wireless Internet module, a short distance communication module, or the like to communicate with the relay200. The mobile communication module transmits and receives a wireless signal to and from at least one of a base station, an external terminal, or a server communicatively connected to a mobile communication network. The wireless Internet module is a module enabling wireless Internet access, and may be mounted inside or outside the lighting controller300. The short distance communication module is a module configured for short distance communication and may include a wireless LAN card.

The wireless LAN card may enable wireless communication in accordance with the 802.11 wireless network standard specification for a wireless LAN proposed by the IEEE, and/or enable wireless communication through a wireless LAN including some infrared communication. The wireless LAN card may alternatively or additionally enable communication in accordance with the 802.15 standard protocol specification for a wireless personal area network (PAN) including Bluetooth, ultra wideband (UWB), ZigBee, or the like. The wireless LAN card may alternatively or additionally enable communication in accordance with the 802.16 standard protocol specification for a wireless metropolitan area network (MAN) broadband wireless access (BWA) including a fixed wireless access (FWA). Alternatively or additionally, the wireless LAN card may enable communication in accordance with the 802.20 mobile Internet standard protocol specification for a wireless mobile broadband wireless access (MBWA) including Wibro, WiMAX, or the like.

The relay200enables wired or wireless communication between the lighting controller300and the lighting apparatus100. For example, the relay200transmits the control message received from the lighting controller300to the lighting apparatus100, and may be an access point (AP), a gateway, or the like. The relay200is separate and distinct from the lighting controller300and the lighting apparatus100in the present embodiment, but is not limited thereto. For example, the relay200may be an element of the lighting controller300in some embodiments.

The relay200may establish a communication connection to one or more external devices such as the lighting controller300, the lighting apparatus100, or the like in response to the external device initiating the establishment of a communication connection. Network information, for example, an Internet protocol (IP) address, a PAN ID (personal area network identification), a device address, a channel, or the like may be assigned to the external device. When the lighting control system1000includes a plurality of lighting apparatuses100, the relay200may communicate with each of the lighting apparatuses100based on the network information.

The relay200may include a mobile communication module, a wireless Internet module, a short distance communication module, or the like, configured for communication across a network connection to the lighting apparatus100and the lighting controller300. The short distance communication module may include a wireless communication module operating according to WiFi, Bluetooth, ZigBee, or similar standards.

When the relay200is operative to relay communication between devices operating according to different communication protocols, the relay200may perform protocol conversion between the devices. For example, when a communication protocol of the lighting controller300is based on the 802.11 wireless network standard specification, and a communication protocol of the lighting apparatus100is based on the 802.15 wireless network standard specification, the relay200may convert a message received from the lighting controller300into the protocol that can be processed by the lighting apparatus100and transmit the converted message to the lighting apparatus100. As described above, when the lighting controller300and the lighting apparatus100operate using different communication protocols, the relay200may include a plurality of communication modules that each communicate according to a different one of the protocols.

External devices between which the relay200is operative to send communications are referred to as relay targets. The relay200may store information regarding the relay target in a storage unit or memory (not shown). The information regarding the relay target (or external device) includes information used to identify the external device such as an IP address of the relay target, a media access control (MAC) address, a product name, function information, or the like. When the relay target is the lighting apparatus100, the relay200may store information regarding a space in which the lighting apparatus100is located in the storage unit. In addition, the relay200may store information regarding a communication protocol used by the relay target in the storage unit.

Although a single relay200is shown and described in the present embodiment, the inventive concept is not limited thereto. The system1000may include multiple relays200. Additionally, each relay200may include a combination of a gateway, an AP, a server, and/or the like. In some examples, the lighting controller300may directly control the lighting apparatus100without the relay200. In such examples, communication messages transmitted by the lighting controller300are directly routed to the light100without passing through the relay200.

The lighting apparatus100is used to emit light and generate specific lighting. The lighting apparatus100may include a plurality of light emitting devices that provide various colors, brightness, and chroma of lighting. The light emitting devices may be light emitting diodes (LEDs) but are not limited thereto. The light emitting devices may be fluorescent lamps. The light emitting devices may be combinations of LEDs and fluorescent lamps. The lighting control system1000may include a plurality of lighting apparatuses100. The lighting controller300may selectively and separately control individual ones of the lighting apparatuses100, may jointly control two or more of the lights100, or may separately control various groupings of one or more lights100.

The lighting apparatus100may be controlled according to a control message from the lighting controller300, for example a control signal or data, and provide data regarding a lighting state to the lighting controller300. The control signal or the data may be transmitted and received by the light100via communication between the lighting apparatus100and the relay200. To this end, the lighting apparatus100may include a mobile communication module, a wireless Internet module, a short distance communication module, or the like. As described above, when the lighting apparatus100is mounted inside a building, the lighting apparatus100may include a ZigBee wireless communication module.

The lighting apparatus100may request communication from the relay200, be permitted for communication from the relay200, and be connected to a network including the relay200. The lighting apparatus100may be assigned and receive an IP address, a PAN ID, a device address, a channel, or the like from the relay200to perform communication.

The lighting apparatus100of the present embodiment may include a non-contact sensor NTS operative to perform a network reset operation so as to allow the lighting apparatus100to be disconnected from the network and reconnected to a new network. When the lighting apparatus100is connected to a wrong network or is not normally or functionally connected to the network, the lighting controller300may not be able to control the lighting apparatus100. In such a situation, a user may need to personally control the lighting apparatus100and reset the network so as to allow the lighting apparatus100to be normally controlled by the lighting controller300. Specifically, the user may need to activate a switch on the light100so as to allow the light100to become associated with the network and communicatively connected to the lighting controller300. However, when the lighting apparatus100emits light for a long time, the user may not be able to directly contact the light100due to a high temperature of the lighting apparatus100. In this regard, the user may use the non-contact sensor NTS to generate a reset signal for resetting the network without having to contact the lighting apparatus100. Additionally, a small-sized lighting apparatus such as a lamp type lighting apparatus may have an insufficient space for accommodating a switch used to reset the network on a surface thereof. Thus, the non-contact sensor NTS may be included in the lighting apparatus and used for this purpose. The non-contact sensor NTS may detect a signal externally generated by the user, for example a magnetic signal generated by allowing a magnetic substance to move near the light100and non-contact sensor NTS according to a user action, and generate the reset signal. The network of the lighting apparatus100may be reset in response to the reset signal. The lighting apparatus100and a method of controlling the lighting apparatus100according to an embodiment of the inventive concept will now be describe below.

FIG. 2is a block diagram of the lighting apparatus100according to an embodiment of the inventive concept. Referring toFIG. 2, the lighting apparatus100may include a communication interface110that communicates with the relay200or the lighting controller300, a non-contact sensor120that detects a non-contact signal from the outside and generates a reset signal, a light source140including a plurality of light emitting devices, a controller130that controls and operates the light source140, and a power supply150that supplies power.

The light source140may include at least one of a red light emitting device that emits red light, a green light emitting device that emits green light, and a blue light emitting device that emits blue light. The light source140may include a plurality of white light emitting devices that emit white light and have different color temperatures. The light source140may have different numbers of light emitting devices according to a size of a space in which light emitting devices are to be installed, the intended uses of the light emitting devices, or the like, and/or may have different numbers or ratios of red light emitting devices, green light emitting devices, blue light emitting devices, and white light emitting devices.

The controller130operates the light source140according to a control message received from the outside. The controller130may turn on or off all or some of light emitting devices of the light source140according to the control message. The controller130may change lighting properties of the light source140such as a temperature of light, brightness, chroma, or the like by changing an amount of current input into different light emitting devices of the light source140or changing a time at which the current is input.

The power supply150may modify a voltage applied from the outside or internally generate a voltage to generate a drive voltage or current used to operate the light source140. In addition, the power supply150may generate and provide a voltage used to power each of the elements of the lighting apparatus100.

The communication interface110may communicatively connect the lighting apparatus100to a network, and may communicate with a remote apparatus such as the relay200(and/or the lighting controller300) to transmit information regarding the lighting apparatus100to the relay200or receive the control message from the relay200. The communication interface110may include a mobile communication module, a wireless Internet module, a short distance communication module, or the like and may communicate with the relay200by using at least one of the received modules. For example, the communication interface110may include a ZigBee communication module as a communication module, and communicate using the ZigBee communication standard with the relay200.

The communication interface110may cause the network to reset in response to receiving a reset signal provided from the non-contact sensor120. Specifically, the communication interface110may disconnect from a previously connected network in response to receiving the reset signal, and may automatically search for available networks and connect to one of the identified available networks following the disconnection. The lighting apparatus100may connect to a new network following disconnection from a previously connected network resulting from the network reset operation, or may reconnect to the same network it was previously connected to.

The non-contact sensor120detects a non-contact signal from the outside and generates a reset signal for resetting the network. The non-contact sensor120may be implemented as a proximity sensor, a Hall sensor, a magnetic resonance (MR) sensor, or the like. A non-contact signal may be a movement of an object near the non-contact sensor120, an electrical or magnetic signal (e.g., a change in magnetic field), or the like. For example, when the non-contact sensor120is a Hall sensor, the non-contact signal may be a magnetic signal. If a magnet or magnetic substance approaches the Hall sensor and a magnetic field is generated in proximity to the sensor, the sensor may detect the magnetic signal and generate a reset signal.

Meanwhile, the non-contact sensor120may generate one of various types of reset signals according to a value of a non-contact signal or a pattern thereof. In this regard, the communication interface110may differentiate between various signals or patterns and determine whether a detected signal or pattern corresponds to a sequence for resetting a network according to the reset signal. A network reset operation performed by the communication interface110according to the reset signal will be described in detail with reference toFIGS. 5 through 7below.

FIG. 3Ais a diagram for explaining an operation of a Hall sensor as an example of a non-contact sensor ofFIG. 2.FIG. 3Bis a graph of an output signal of the Hall sensor.

The Hall sensor is a sensor that produces an output signal based on the Hall effect. The Hall effect is the production of a voltage in a direction perpendicular to a magnetic field if the magnetic field is applied to a conductor through which a current flows. Referring toFIG. 3A, the Hall sensor may include a conductor CO through which current I flows. If a magnetic field B is generated by allowing a magnetic substance MO such as a magnet to move near the Hall sensor, a voltage V may be generated in a direction perpendicular to the magnetic field B. If the voltage V of a predetermined level is generated, the Hall sensor may detect an occurrence of a non-contact signal, i.e. a magnetic signal, and generate a reset signal.

Meanwhile, when a polarity of the magnetic substance MO approaching the Hall sensor is changed, a polarity of the voltage V may be changed as shown inFIG. 3B. Referring toFIG. 3B, the voltage V is not generated when the magnetic substance MO does not approach the Hall sensor, whereas the voltage V is generated when the magnetic substance MO approaches the Hall sensor. A positive voltage +V or a negative voltage −V may be generated according to the polarity of the magnetic substance MO. The Hall sensor may generate the reset signal based on the generated voltage V, and generate a first reset signal or a second reset signal according to the polarity of the magnetic substance MO as described above. The Hall sensor generates a first reset signal when a polarity of the approaching magnetic substance is an N electrode, and generates a second reset signal when the polarity of the approaching magnetic substance is an S electrode. The Hall sensor may also selectively generate the first reset signal or the second reset signal according to a signal generation pattern, for example depending on whether a non-contact signal is detected one time, multiple times (e.g., two times), or continuously (e.g., continuously for a period of time exceeding a predetermined threshold). In addition, the Hall sensor may generate a plurality of different reset signals in response to having applied thereto various signal generation patterns.

FIG. 4Ais a diagram for explaining an operation of a magneto resistive (MR) sensor as an example of the non-contact sensor120ofFIG. 2.FIG. 4Bis a graph of an output signal of the MR sensor. The MR sensor is a sensor that produces an output signal based on a magnetic resistance effect in which a magnetic resistance of a material varies due to a magnetic field. The MR sensor may detect a variation of a magnetic field or an existence of a magnetic substance as a variation of a voltage. Referring toFIG. 4A, the MR sensor includes two MR devices MR1 and MR2 connected in series, and applies a voltage V across the series connection of MR devices MR1 and MR2. Magnetic fields B1 and B2 are respectively applied to the MR devices MR1 and MR2, and a node common to the MR devices MR1 and MR2 is set as an output node. In this regard, if the magnetic fields B1 and B2 applied to the MR devices MR1 and MR2 are the same, no signal is generated. However, if the magnetic substance MO approaches only one of the MR devices MR1 and MR2, the magnetic fields B1 and B2 become unequal and the resistance values of the MR devices MR1 and MR2 are changed. As a result, an output voltage Vout is changed. Referring toFIG. 4B, when the magnetic fields B1 and B2 applied to the MR devices MR1 and MR2 are the same, an output voltage Vout is a predetermined reference voltage, for example, ½*V. If the magnetic field B2 applied to the MR device MR2 becomes stronger, the resistance of the MR device MR2 increases and the output voltage Vout increases (+). In contrast, if the magnetic field B1 applied to the MR device MR1 becomes stronger, the resistance of the MR device MR1 increases and the output voltage Vout decreases (−). The MR sensor may detect whether the output voltage Vout increases or decreases compared to a predetermined reference voltage, i.e., the output voltage Vout when the magnetic fields B1 and B2 are the same (e.g., ½*Vout). The MR sensor can then determine that a non-contact signal is applied to the sensor, and generate a reset signal according to results of the determination. In this regard, the MR sensor may generate a first reset signal or a second reset signal according to whether the output voltage Vout increases (+) or decreases (−). Alternatively, the MR sensor may generate a first reset signal or a second reset signal according to a pattern of the detected non-contact signal such as whether a variation of the output voltage Vout occurs one time, multiple times (e.g., two times), or continuously for a predetermined period of time. In addition, the MR sensor may generate a plurality of different types of reset signals in response to having applied thereto various signal generation patterns.

The operation of the Hall sensor and the MR sensor as non-contact sensors is described above. Various other types of non-contact sensors may be additionally or alternatively be used in the lighting apparatus in accordance with the inventive concept.

FIG. 5is a detailed block diagram showing components of the communication interface110of the lighting apparatus100ofFIG. 2according to an embodiment of the inventive concept. The non-contact sensor120is also shown for convenience of description.

Referring toFIG. 5, the communication interface110may include an interface unit11, a network setting unit12, and a storage unit13.

The interface unit11transmits and receives a signal to and from an external apparatus connected to a network by using a set communication methods and protocols. For example, the interface unit11may communicate with the external apparatus by using a ZigBee protocol, and may additionally be operative to communicate according to several other protocols.

The network setting unit12searches for a network that may be used to communicate with the lighting apparatus100and connects the lighting apparatus100to the network. For example, if power is applied to the lighting apparatus100, the network setting unit12determines whether the lighting apparatus100is connected to a network. In this regard, the network setting unit12may determine whether the lighting apparatus100is connected to a network according to a value of a data bit indicating a connection to the network. The network setting unit12also may determine whether the lighting apparatus100is connected to a network according to whether network information is stored in the storage unit13or is valid. The network information may include an IP address, a PAN ID, a device address, a channel, or the like. If the network information is not stored in the storage unit13, the network setting unit12may determine that the lighting apparatus100is not connected to the network. The network setting unit12may request a connection to the network based on the network information stored in the storage unit13. If there is no response to the request and the network information is not valid, the network setting unit12may determine that the lighting apparatus100is not connected to any network. If the network setting unit12determines that the lighting apparatus100is not connected to any network, the network setting unit12may search for networks that may be used to communicate with the lighting apparatus100, identify one or more candidate networks in response to the search, and request a connection to a selected one of the candidate networks by sending a request to the relay200of the selected network. In response to sending the request, the network setting unit12may receive a response from the relay200indicating that the lighting apparatus100may connect to the selected network and including network information for use by the lighting apparatus100and the relay200while communicating across the network.

The network setting unit12may reset the network if a reset signal RST is received from the non-contact sensor120. In response to receiving a reset signal RST, the network setting unit12disconnects the lighting apparatus100from the network. Furthermore, the network setting unit12may search for a candidate network and, once a candidate network is found, connect the lighting apparatus100to the found network. The network search and connection may be performed a predetermined period of time after the lighting apparatus has disconnected from the previously connected network. The lighting apparatus100may connect to the previously connected network or to a new or different network.

In this regard, the disconnection from the network may include the network setting unit12deleting the network information stored in the storage unit13or changing a value of a data bit indicating the connection to the network.

Meanwhile, in embodiments in which various types of reset signals RST are generated by the non-contact sensor120, the network setting unit12may perform a different reset operation depending on the particular reset signal RST received. For example, the network setting unit12may reconnect the lighting apparatus100to the previously connected network if a first reset signal rst1is received, and may search for a new network (e.g., a network different from the previously connected network) and connect the lighting apparatus100to the new network if a second reset signal rst2is received. This will be described in more detail with reference toFIGS. 7A and 7B.

The storage unit13may store information necessary for connecting to and communicating through a network. The storage unit13may store the network information assigned to the lighting apparatus100by the relay200ofFIG. 1or the lighting controller300ofFIG. 1in response to the lighting apparatus100connecting to the associated network. The network information may include, for example, the IP address, the PAN ID, the device address, the channel, or the like, to be used for communication across the network. The storage unit13may store a network connection algorithm that is automatically accessed by the network setting unit12and used to search for and connect to a network during an initial operation of the lighting apparatus100.

The storage unit13may be a non-volatile memory, and may be any of a flash memory, an electrically erasable programmable read only memory (EEPROM), a magnetic random access memory (MRAM), a phase change memory (PRAM), or the like.

FIG. 6is a flowchart illustratively showing a method for controlling the lighting apparatus100according to an embodiment of the inventive concept.

Referring toFIG. 6, a determination is made as to whether a signal, for example a non-contact signal generated in response to a magnet being located in proximity to (or outside of) the lighting apparatus100, is detected (operation5110). The generation of the non-contact signal is detected by using the non-contact sensor120. The detection may be performed if power is applied to the lighting apparatus100irrespective of whether the lighting apparatus100normally operates or is connected to a network.

If it is detected that the non-contact signal is generated, a reset signal is generated (operation S120). For example, when the non-contact sensor120is a Hall sensor, if a user approaches a magnet or other magnetic substance near the lighting apparatus100, the Hall sensor may generate a voltage. When the voltage is greater than a reference voltage, the Hall sensor may determine that the non-contact signal, i.e. a magnetic signal, is detected and may generate the reset signal

If the reset signal is generated, the communication interface110disconnects the lighting apparatus100from a network in response to the reset signal (operation S130) if the lighting apparatus100was connected to the network. Thereafter, an operation of searching for a new network is performed (operation S140), and if a new network is identified, the lighting apparatus100connects to the new network. In this regard, the lighting apparatus100may connect to the network from which the lighting apparatus100was disconnected in step S130, or may connect to another network.

FIG. 7Ais a flowchart of a method of controlling the lighting apparatus100according to another embodiment of the inventive concept.FIG. 7Bis a flowchart of the method ofFIG. 7Athat is performed in a first reset mode.FIG. 7Cis a flowchart of the method ofFIG. 7Athat is performed in a second reset mode.

Referring toFIG. 7A, a determination is made as to whether a signal, for example a non-contact signal generated in response to a magnet being located in proximity to (or outside of) the lighting apparatus100, is detected (operation S210). The generation of the non-contact signal is detected by using the non-contact sensor120. The detection may be performed if power is applied to the lighting apparatus100irrespective of whether the lighting apparatus100normally operates or is connected to a network.

If it is detected that the non-contact signal is generated, a reset signal is generated (operation S220). In this regard, the non-contact sensor120may selectively generate one of a first reset signal or a second reset signal depending on a value of the non-contact signal or a pattern thereof.

If a reset signal is generated, the lighting apparatus100is disconnected from a network (operation S230).

Thereafter, if the reset signal generated in step S220is the first reset signal, the lighting apparatus100operates in the first reset mode (operation S240) and reconnects to the network from which the lighting apparatus100disconnected in step S230. If the reset signal generated in step S220is the second reset signal, the lighting apparatus100operates in the second reset mode (operation S250) and connects to another network different from the network from which the lighting apparatus100disconnected in step S230.

Referring toFIG. 7B, as part of operation S240of the first reset mode, the lighting apparatus100searches for one or more networks to connect to (operation S241). A determination is made as to whether a found network is the network from which the lighting apparatus100disconnected in step S230(operation S242). It may be determined whether the found network is the network from which the lighting apparatus100was disconnected by identifying a PAN ID of the found network. If the PAN ID of the found network is identical to or otherwise matches network information stored in the storage unit130, e.g. stored network information including a PAN ID of the network from which the lighting apparatus100was disconnected, the found network may be determined to be the network from which the lighting apparatus100was disconnected. In this regard, if the found network is the network from which the lighting apparatus100was disconnected, the lighting apparatus100may connected to the found network (operation S243). Alternatively, if the found network is not the network from which the lighting apparatus100was disconnected, operation returns to operation S241such that another network can be searched for.

Referring toFIG. 7C, as part of operation S250of the second reset mode, the lighting apparatus100searches for one or more networks to connect to (operation S251). A determination is made as to whether a found network is the network from which the lighting apparatus100disconnected in step S230(operation S252). If the found network is not the network from which the lighting apparatus100disconnected, the lighting apparatus100may connect to the found network which corresponds to a network other than the network from which the lighting apparatus100was disconnected in operation S230(operation S253). Alternatively, if the found network is the network from which the lighting apparatus100disconnected, operation returns to operation S251such that another network can be searched for.

FIG. 8is a diagram for explaining connections between lighting apparatuses and a plurality of networks according to an embodiment of the inventive concept.

As shown inFIG. 8, when relays CD1 and CD2 are respectively installed in two neighboring houses H1 and H2, different networks exist. The first relay CD1 controls lighting apparatuses L11, L12, and L13 installed inside the house H1, and the second relay CD2 controls lighting apparatuses L21, L22, and L23 installed inside the house H2. However, when a new lighting apparatus or an additional lighting apparatus is installed, the new lighting apparatus or the additional lighting apparatus may be connected to an unwanted network. For example, the lighting apparatus L13 that needs to communicate with the first relay CD1 may be connected to a network of the neighboring house H2, i.e. a network of the second relay CD2. In this case, the first relay CD1 is unable to control the lighting apparatus L13 connected to the other network. In this regard, the lighting apparatus L13 may be a lighting apparatus100ofFIG. 1according to the present embodiment. The lighting apparatus L13 may be disconnected from the network of the neighboring house H2 and reconnected to a network of house H1 in response to a reset signal generated by a non-contact sensor120of lighting apparatus L13. For example, a user may generate a non-contact signal by approaching a magnet or other magnetic substance to the non-contact sensor120of lighting apparatus L13. The non-contact sensor120may detect the non-contact signal, and generate the reset signal. In this regard, the lighting apparatus L13 needs to be connected to the first relay CD1 and not to the second relay CD2. As described with reference toFIGS. 7A to 7Cin which a lighting apparatus operates differently according to a type of the reset signal, the user may cause the non-contact sensor120to generate a second reset signal. In response to the second reset signal, the lighting apparatus L13 operates according to the second reset mode described with reference toFIG. 7Cabove. As a result, lighting apparatus L13 disconnects from the network of house H2 and connects instead to the network of house H1. Alternatively, when the lighting apparatus needs to be reconnected to the same network it is currently connected to, the user may cause the non-contact sensor120to generate the first reset signal such that the lighting apparatus L13 operates in accordance with the first reset mode described with reference toFIG. 7Babove.

FIG. 9is an exploded perspective view of a lamp according to an embodiment of the inventive concept.FIG. 10is an International Commission on Illumination (CIE) chromaticity diagram of a Planckian spectrum. A lighting apparatus2100may include a socket2190, a power supply2150, a controller2130, a heat dissipator2160, a light source2140, an optic unit2170, a communication interface2110, a non-contact sensor2120, and a cover2180.

The socket2190may be configured to enable the lighting apparatus2100to easily replace and fit into a fixture designed for an existing lighting apparatus. Power may be supplied to the lighting apparatus2100via the socket2190. The power supply2150may generate a voltage used in each element of the lighting apparatus2100based on power supplied from the outside through the socket2190.

The heat dissipator2160may include an internal heat dissipation unit2161and an external heat dissipation unit2162. The internal heat dissipation unit2161may be connected to the light source2140and/or the power supply2150, and may provide a conduit through which heat may be transferred to the external heat dissipation unit2162.

The light source2140may receive power from the power supply2150and emit light. The light source2140may include one or more light emitting devices C or one or more light emitting device packages2141, and a circuit substrate2142.

The optic unit2170may be disposed on the light source2140. The optic unit2170may uniformly diffuse light emitted from the light source2140to lateral and rear directions so that the lighting apparatus2100may emit light to the top and bottom to prevent eyes from being dazzled. The optic unit2170may be a reflective plate, a lens, or the like.

The cover2180is mounted on the light source2140and the optic unit2170to protect the light source2140and the optic unit2170from the outside. A diffusion material may be coated or charged in an inner surface of the cover2180so that the light emitted from the light source2140may well diffuse through the cover2180. The cover2180may be formed of a transparent plastic material, a glass material, or a translucent plastic material based on polycarbonate (PC), polymethyl methacrytlate (PMMA), acrylic, or the like, and combination of the diffusion material and these transparent materials. The cover2180may be formed of a combination of a phosphor and transparent materials so that a color conversion of light emitted from the light source2140may be facilitated.

The communication interface2110may be mounted on the optic unit2170in a module form and may be used to perform network communication. For example, the communication interface2110is a wireless communication module using a ZigBee protocol and may control an in-house lighting apparatus such as turning the lamp on/off, adjusting of brightness thereof, or the like by using a smart phone or a wireless lighting controller.

The non-contact sensor2120may be mounted on the optic unit2170or the communication interface2110. If a user approaches a magnetic substance near the non-contact sensor2120, the non-contact sensor2120may generate a reset signal and provide the reset signal to the communication interface2110. The communication interface2110may then disconnect the lighting apparatus2100from a network in response to the reset signal, search for a new network, and connect the lighting apparatus2100to the new network as part of a network reset operation.

A non-contact signal such as a magnetic signal and an electromagnetic wave used in wireless communication may easily transmit through the cover2180formed of a plastic material. Thus, the non-contact sensor2120and the communication interface2110may be disposed on the optic unit2170or in a front portion of the light source2140as shown inFIG. 9such that the non-contact signal can be easily detected and the communication interface2110can readily communicate wirelessly with an external apparatus. However, the inventive concept is not limited thereto. The non-contact sensor2120and the communication interface2110may be disposed inside the internal hear dissipation unit2161. The non-contact sensor2120and the communication interface2110may be disposed on the circuit substrate2140of the light source unit2140.

Meanwhile, the light emitting device packages2141included in the light source2140may be similar devices that generate light having the same wavelength. Alternatively, the light emitting device packages2141may be dissimilar devices that generate light having different wavelengths from light generated by other ones of the light emitting device packages2141. For example, the light emitting device packages2141may include at least one of a light-emitting device that is combination of a blue-light light emitting device and a phosphor having a color of yellow, green, red, or orange and that emits white light, and a light-emitting device that emits a purple color, a blue color, a green color, a red color, or infrared light. In this case, the lighting apparatus2100may adjust a Color Rendering Index (CRI) of a solar level in sodium (Na) and also may generate a variety of white light having color temperatures ranging from 1500° K to 20000° K, and when required, the lighting apparatus may adjust a lighting color according to the ambient atmosphere or mood by generating visible light having a color of purple, blue, green, red, or orange, or infrared light. Also, the lighting apparatus may2100generate light having a special wavelength capable of promoting a growth of plants.

White light that corresponds to a combination of the blue-light light emitting device and the yellow, green, and red phosphors and/or green and red light-emitting devices may have at least two peak wavelengths and may be positioned at a line segment connecting (x, y) coordinates (0.4476, 0.4074), (0.3484, 0.3516), (0.3101, 0.3162), (0.3128, 0.3292), and (0.3333, 0.3333) of a CIE 1931 coordinate system ofFIG. 10. Alternatively, the white light may be positioned in a region that is surrounded by the line segment and a blackbody radiation spectrum. A color temperature of the white light may be between 2000° K through 20000° K.

Phosphors that are used in a light emitting device may have general formulas and colors as below.

FIG. 11is a lateral cross sectional view of a light emitting device chip1500that may be used in a light emitting device C ofFIG. 9according to an embodiment of the inventive concept. As shown inFIG. 11, the light emitting device chip1500includes a light emitting stack S formed on a substrate1501. The light emitting structure S includes a first conductive semiconductor layer1504, an active layer1505, and a second conductive semiconductor layer1506.

The light emitting device chip1500includes an ohmic electrode layer1508formed on the second conductive semiconductor layer1506. First and second electrodes1509aand1509bare formed on top surfaces of the first conductive semiconductor layer1504and the ohmic electrode layer1508respectively.

Throughout the specification, terms such as ‘upper’, ‘top surface’, ‘lower’, ‘bottom surface’, ‘side surface’, or the like are based on drawings; thus, they may be changed according to a direction in which a device is actually disposed.

Main elements of the light emitting device chip1500will now be described in detail below.

An insulating, conductive, or semiconductor substrate may be used as the substrate1501according to necessity. For example, the substrate1501may be sapphire, SiC, Si, MgAl2O4, MgO, LiAlO2, LiGaO2, or GaN. A sapphire substrate, silicon carbide (SiC) substrate, or the like may be mainly used as a heterogeneous substrate. When the heterogeneous substrate is used, a defect such as dislocation may increase due to a difference in a lattice constant between a substrate material and a thin film material. Due to a difference between thermal expansion coefficients of the substrate material and the thin film material, the substrate1501may be bent when a temperature is changed, and the bend causes a crack of a thin film. The problem may be decreased by using a buffer layer1502between the substrate1501and the light emitting stack S that includes a GaN material.

The buffer layer1502may be formed of AlxInyGa1-x-yN (0≦x≦1, 0≦y≦1), in particular, GaN, AlN, AlGaN, InGaN, or InGaNAlN, and when required, the buffer layer1502may be formed of ZrB2, HfB2, ZrN, HfN, TiN, or the like. Also, the buffer layer1502may be formed by combining a plurality of layers or by gradually varying composition of one of the materials.

Each of the first and second conductive semiconductor layers1504and1506may have a single-layer structure. However, when required, each of the first and second conductive semiconductor layers1504and1506may have a multi-layer structure including a plurality of layers having different compositions or thicknesses. For example, each of the first and second conductive semiconductor layers1504and1506may have a carrier injection layer capable of improving an efficiency of electron and hole injection, and may also have a superlattice structure having various forms.

The first conductive semiconductor layer1504may further include a current diffusion layer (not shown) that is adjacent to the active layer1505. The current diffusion layer may have a structure in which a plurality of InxAlyGa(1-x-y)N layers having different compositions or different impurity ratios are repeatedly stacked, or may be partially formed of an insulation material layer.

The second conductive semiconductor layer1506may further include an electron block layer (not shown) that is adjacent to the active layer1505. The electron block layer may have a structure in which a plurality of InxAlyGa(1-x-y)N layers having different compositions are stacked or may have at least one layer formed of AlyGa(1-y)N. Since the electron block layer has a bandgap larger than that of the active layer1505, the electron block layer prevents electron from entering to the second conductive semiconductor layer1506(that is a p-type).

The light emitting stack S is formed by using an metal-organic chemical vapor deposition (MOCVD) apparatus. In more detail, the light emitting device stack S is formed in a manner in which a reaction gas such as an organic metal compound gas (e.g., trimethyl gallium (TMG), trimethyl aluminum (TMA), or the like) and a nitrogen containing gas (e.g. ammonia (NH3), or the like) are injected into a reaction container in which the substrate1501is arranged and the substrate1501is maintained at a high temperature of about 900 through 1100 degrees, while a gallium-based compound semiconductor is grown on the substrate1501, if required, an impurity gas is injected, so that the gallium-based compound semiconductor is stacked as an undoped-type, an n-type, or a p-type. Si is well known as n-type impurity. Zn, Cd, Be, Mg, Ca, Ba, or the like, in particular, Mg and Zn, may be used as p-type impurity.

The active layer1505that is disposed between the first and second conductive semiconductor layers1504and1506may have a multi-quantum well (MQW) structure in which a quantum well layer and a quantum barrier layer are alternately stacked. For example, in a case of a nitride semiconductor, the active layer1505may have a GaN/InGaN structure. However, in another embodiment, the active layer1505may have a single-quantum well (SQW) structure.

The ohmic electrode layer1508may decrease an ohmic contact resistance by relatively increasing an impurity density, so that the ohmic electrode layer1508may decrease an operating voltage and may improve a device characteristic. The ohmic electrode layer1508may be formed of GaN, InGaN, ZnO, or a graphene layer.

While the light emitting device chip1500shown inFIG. 11has a structure in which the first electrode1509a, the second electrode1509b, and a light extraction surface face the same side, the LED chip1500may have various structures such as a flip-chip structure in which the first electrode1509aand the second electrode1509bface the opposite side of the light extraction surface, a vertical structure in which the first electrode1509aand the second electrode1509bare formed on opposite surfaces, a vertical and horizontal structure employing an electrode structure in which a plurality of vias are formed in a chip so as to increase an efficiency of current distribution and heat dissipation.

FIG. 12is a lateral cross sectional view of a light emitting device chip1600that may be used in the light emitting device C ofFIG. 9according to another embodiment of the inventive concept. The light emitting device chip1600ofFIG. 12may be used as a structure useful for increasing an efficiency of current distribution and heat dissipation, when a large area light-emitting device chip for a high output lighting apparatus is manufactured.

Referring toFIG. 12, the light emitting device chip1600includes a first conductive semiconductor layer1604, an active layer1605, a second conductive semiconductor layer1606, a second electrode layer1607, an insulating layer1602, a first electrode layer1608, and a substrate1601that are sequentially stacked. In this regard, in order to be electrically connected to the first conductive semiconductor layer1604, the first electrode layer1608includes one or more contact holes H that are electrically insulated from the second conductive semiconductor layer1606and the active layer1605and that extend from a surface of the first electrode layer1608to a portion of the first conductive semiconductor layer1604. In the present embodiment, the first electrode layer1608is not an essential element.

The contact hole H extends from an interface of the first electrode layer1608to an inner surface of the first conductive semiconductor layer1604via the second conductive semiconductor layer1606and the active layer1605. The contact hole H extends to an interface between the active layer1605and the first conductive semiconductor layer1604, and more preferably, the contact hole H extends to the portion of the first conductive semiconductor layer1604. Since the contact hole H functions to perform electrical connection and current distribution of the first conductive semiconductor layer1604, the contact hole H achieves its purpose when the contact hole H contacts the first conductive semiconductor layer1604, thus, it is not required for the contact hole to extend to an outer surface of the first conductive semiconductor layer1604.

The second electrode layer1607that is formed on the second conductive semiconductor layer1606may be formed of a material selected from the group consisting of Ag, Ni, Al, Rh, Pd, Ir, Ru, Mg, Zn, Pt, and Au, in consideration of a light reflection function and an ohmic contact with the second conductive semiconductor layer1606, and may be formed via a sputtering process or a deposition process.

The contact hole H has a shape that penetrates through the second electrode layer1607, the second conductive semiconductor layer1606, and the active layer1605so as to be connected with the first conductive semiconductor layer1604. The contact hole H may be formed via an etching process using ICP-RIE or the like.

The insulating layer1602is formed to cover side walls of the contact hole H and a top surface of the second conductive semiconductor layer1606. In this case, a portion of the first conductive semiconductor layer1604that corresponds to a bottom surface of the contact hole H may be exposed. The insulating layer1602may be formed by depositing an insulation material such as SiO2, SiOxNy, SixNy, or the like. The insulating layer1602may be deposited at a thickness range from about 0.01˜about 3 μm at 500° C. or below through a CVD process.

The second electrode layer1607that includes a conductive via formed by filling a conductive material is formed in the contact hole H. A plurality of vias may be formed in one light emitting device region. The number of the vias and contact areas may be adjusted only when an area of the vias on a plane of a region in which the vias and the first conductive semiconductor layer1604contact each other is within a range from about 1%˜5% of an area of the light emitting device. A radius of the vias on the plane of the region in which the vias and the first conductive semiconductor layer1604contact each other may have a range, for example, from about 5 μm˜about 50 μm. The number of the vias may have a range from about 1˜about 50 for each light emitting device region according to a size of the light emitting device region. Although the vias vary according to the size of the light emitting device region, the number of the vias may be 3 or more. Distances between the vias may have a matrix structure having rows and columns in a range from about 100 μm and about 500 μm, and may be in a range from about 150 μm and about 450 μm. If the distances between the vias are smaller than 100 μm, the number of the vias increases, and a light emitting area relatively decreases, whereas if the distances between the vias are greater than 100 μm, a current diffusion becomes difficult, which reduces emission efficiency. A depth of the via may vary according to thicknesses of the active layer1605and the second conductive semiconductor layer1606and may be a range from about 0.5 μm˜about 5.0 μm.

Thereafter, the substrate1601is formed on the first electrode layer1608. In this structure, the substrate1601may be electrically connected to the first conductive semiconductor layer1604via the conductive via that contacts the first conductive semiconductor layer1604.

The substrate1601may be formed of, but is not limited to, a material selected from the group consisting of Au, Ni, Al, Cu, W, Si, Se, GaAs, SiAl, Ge, SiC, AlN, Al2O3, GaN, and AlGaN, via a plating process, a sputtering process, a deposition process, or an adhesion process.

In order to decrease a contact resistance of the contact hole H, a total number of the contact holes H, a shape of the contact hole H, a pitch of the contact hole H, a contact area of the contact hole H with respect to the first and second conductive semiconductor layers1604and1606, or the like may be appropriately adjusted, and since the contact holes H are arrayed in various forms along lines and columns, a current flow may be improved.

It is preferable to apply a light emitting device chip having a small calorific value to the lighting apparatus, in consideration of a total heat dissipation performance. An example of the light emitting device chip having a small calorific value may be an light emitting device chip having a nano structure (hereinafter, referred to as a “nano light emitting device chip”).

An example of the nano light emitting device chip includes a core-shell type nano light emitting device chip that has recently been developed. The core-shell type nano light emitting device chip generates a relatively small amount of heat due to its small combined density, and increases its light emitting area by using the nano structure so as to increase emission efficiency. Also, the core-shell type nano light emitting device chip may obtain a non-polar active layer, thereby preventing efficiency deterioration due to polarization, so that a drop characteristic may be improved.

FIG. 13is a lateral cross sectional view of a nano light emitting device chip1700that may be used in the light emitting device C ofFIG. 9according to another embodiment of the inventive concept. As shown inFIG. 13, the nano light emitting device chip1700includes a plurality of nano emission structures (not shown) that are formed on a substrate1701. In the present embodiment, the nano emission structure N has a rod structure as a core-shell structure, but in another embodiment, the nano light emitting structure N may have a different structure such as a pyramid structure.

The nano light emitting device chip1700includes a base layer1702formed on the substrate1701. The base layer1702may be a layer to provide a growth surface for the nano emission structures N and may be formed of a first conductive semiconductor. A mask layer1703having open areas for a growth of the nano light emitting structures N (in particular, a core) may be formed on the base layer1702. The mask layer1703may be formed of a dielectric material such as SiO2or SiNx.

In the nano light emitting structure N, a first conductive nano core1704is formed by selectively growing the first conductive semiconductor by using the mask layer1703having open areas, and an active layer1705and a second conductive semiconductor layer1706are formed as a shell layer on a surface of the first conductive nano core1704. By doing so, the nano emission structure N may have a core-shell structure in which the first conductive semiconductor is a nano core, and the active layer1705and the second conductive semiconductor layer1706that surround the nano core are the shell layer.

In the present embodiment, the nano light emitting device chip1700includes a filling material1707that fills gaps between the nano light emitting structures N. The filling material1707may structurally stabilize the nano light emitting structures N. The filling material1707may include, but is not limited to, a transparent material such as SiO2. An ohmic contact layer1708may be formed on the nano light emitting structure N so as to contact the second conductive semiconductor layer1706. The nano light emitting device chip1700includes first and second electrodes1709aand1709bthat contact the base layer1702, which is formed of the first conductive semiconductor, and the ohmic contact layer1708, respectively.

By varying a diameter, a component, or a doping density of the nano light emitting structure N, light having at least two different wavelengths may be emitted from one device. By appropriately adjusting the light having the different wavelengths, white light may be realized in the one device without using a phosphor. In addition, by combining the one device with another light emitting chip or combining the one device with a wavelength conversion material such as a phosphor, light having desired various colors or white light having different color temperatures may be realized.

FIG. 14is a lateral cross sectional view of a semiconductor light emitting device1800including a light emitting device chip that is mounted on a mounting substrate and may be used in the light emitting device C ofFIG. 9according to an embodiment of the inventive concept. The semiconductor light emitting device1800ofFIG. 14includes the mounting substrate1820and the light emitting device chip1810that is mounted on the mounting substrate1820. The light emitting device chip1810is different from the light emitting device chips in the aforementioned embodiments.

The light emitting device chip1810includes an emission stack S that is disposed on a surface of the substrate1801, and first and second electrodes1808aand1808bthat are disposed on a surface of the emission stack S opposite to the substrate1801. Also, the light emitting device chip1810includes an insulation unit1803to cover the first and second electrodes1808aand1808b.

The first and second electrodes1808aand1808bmay include first and second electrode pads1819aand1819bvia first and second electric power connection units1809aand1809b.

The emission stack S may include a first conductive semiconductor layer1804, an active layer1805, and a second conductive semiconductor layer1806that are sequentially disposed on the substrate1801. The first electrode1808amay be provided as a conductive via that contacts the first conductive semiconductor layer1804by penetrating through the second conductive semiconductor layer1806and the active layer1805. The second electrode1808bmay contact the second conductive semiconductor layer1806. A plurality of vias may be formed in one light emitting device region. The number of the vias and contact areas may be adjusted only when an area of the vias on a plane of a region in which the vias and the first conductive semiconductor layer1804contact each other is within a range from about 1%˜5% of an area of the light emitting device. A radius of the vias on the plane of the region in which the vias and the first conductive semiconductor layer1804contact each other may have a range, for example, from about 5 μm˜about 50 μm. The number of the vias may have a range from about 1˜about 50 for each light emitting device region according to a size of the light emitting device region. Although the vias vary according to the size of the light emitting device region, the number of the vias may be 3 or more. Distances between the vias may have a matrix structure having rows and columns in a range from about 100 μm and about 500 μm, and may be in a range from about 150 μm and about 450 μm. If the distances between the vias are smaller than 100 μm, the number of the vias increases, and a light emitting area relatively decreases, whereas if the distances between the vias are greater than 100 μm, a current diffusion becomes difficult, which reduces emission efficiency. A depth of the via may vary according to thicknesses of the active layer1605and the second conductive semiconductor layer1606and may be a range from about 0.5 μm˜about 5.0 μm.

The first and second electrodes1808aand1808bmay be formed by depositing a conductive ohmic material on the emission stack S. The first and second electrodes1808aand1808bmay be electrodes including at least one of Ag, Al, Ni, Cr, Cu, Au, Pd, Pt, Sn, Ti, W, Rh, Ir, Ru, Mg, Zn or an alloy including these materials. For example, the second electrode1808bis formed by depositing an ohmic electrode of an Ag layer with respect to the second conductive semiconductor layer1806. The Ag ohmic electrode acts as a light reflective layer. Single layers of Ni, Ti, Pt, and W or an alloy layer of these layers may be selectively deposited alternately on the Ag layer. In more detail, a Ni/Ti layer, a Ti/Pt layer, or a Ti/W layer may be deposited or these layers may be alternately disposed below the Ag layer.

The first electrode1808ais formed by depositing a Cr layer with respect to the first conductive semiconductor layer1804, sequentially stacking Au/Pt/Ti layers on the Cr layer or depositing an Al layer with respect to the second conductive semiconductor layer1806and sequentially stacking Ti/Ni/Au layers on the Al layer.

The first and second electrodes1808aand1808bmay apply various materials or stack structures so as to increase an ohmic or reflection characteristic in addition to the embodiment.

The insulation unit1803may have an open area to expose a portion of the first and second electrodes1808aand1808b, and the first and second electrode pads1819aand1819bmay contact the first and second electrodes1808aand1808b. The insulating layer1803may be deposited at a thickness range from about 0.01˜about 3 μm at 500° C. or below through a SiO2 and/or SiN CVD process.

The first and second electrodes1808aand1808bmay be disposed in the same direction, and as will be described later, the first and second electrodes1808aand1808bmay be mounted in the form of a flip-chip in a lead frame. In this case, the first and second electrodes1808aand1808bmay be disposed to face in the same direction.

In particular, a first electric power connection unit1809amay be formed by the first electrode1808a, namely, by the conductive via that penetrates through the active layer1805and the second conductive semiconductor layer1806and then is connected to the first conductive semiconductor layer1804in the emission stack S.

In order to decrease a contact resistance between the conductive via and the first electric power connection unit1809a, a total number, shapes, pitches, a contact area with the first conductive semiconductor layer1804, or the like of the conductive via and the first electric power connection unit1809amay be appropriately adjusted, and since the conductive via and the first electric power connection unit1809aare arrayed in rows and columns, a current flow may be improved.

An electrode structure of the other side of the semiconductor light-emitting device1800may include the second electrode1808bthat is directly formed on the second conductive semiconductor layer1806, and the second electric power connection unit1809bthat is formed on the second electrode1808b. The second electrode1808bmay function to form an electrical ohmic connection with the second electric power connection unit1809band may be formed of a light reflection material, so that, when the light emitting device chip1810is mounted as a flip-chip structure as illustrated inFIG. 14, the second electrode1808bmay efficiently discharge light, which is emitted from the active layer1805, toward the substrate1801. Obviously, according to a major light emission direction, the second electrode1808bmay be formed of a light-transmitting conductive material such as transparent conductive oxide.

The aforementioned two electrode structures may be electrically separated from each other by using the insulation unit1803. Any material or any object having an electrical insulation property may be used as the insulation unit1803, but it is preferable to use a material having a low light-absorption property. For example, silicon oxide or silicon nitride such as SiO2, SiOxNy, SixNy or the like may be used. When required, the insulation unit1803may have a light reflection structure in which a light reflective filler is distributed throughout a light transmitting material.

The first and second electrode pads1819aand1819bmay be connected to the first and second electric power connection units1809aand1809b, respectively, and thus may function as external terminals of the light emitting device chip1810. For example, the first and second electrode pads1819aand1819bmay be formed of Au, Ag, Al, Ti, W, Cu, Sn, Ni, Pt, Cr, NiSn, TiW, AuSn, or a eutectic alloy thereof. In this case, when the first and second electrode pads1819aand1819bare mounted on the mounting substrate1820, the first and second electrode pads1819aand1819bmay be bonded to mounting substrate1820by using eutectic metal, so that a separate solder bump that is generally used in flip-chip bonding may not be used. Compared to a case of using the solder bump, the mounting method using the eutectic metal may achieve a more excellent heat dissipation effect. In this case, in order to obtain the excellent heat dissipation effect, the first and second electrode pads1819aand1819bmay be formed while having large areas.

The substrate1801and the emission stack S may be understood by referring to the description with reference toFIG. 11, unless contrary description is provided. Also, although not particularly illustrated inFIG. 14, a buffer layer (not shown) may be formed between the light emitting stack S and the substrate1801, and in this regard, the buffer layer may be formed as a undoped semiconductor layer including nitride or the like, so that the buffer layer may decrease a lattice defect of an emission structure that is grown on the buffer layer.

The substrate1801may have first and second primary surfaces that face each other, and in this regard, a convex-concave structure may be formed on at least one of the first and second primary surfaces. The convex-concave structure that is arranged on one surface of the substrate1801may be formed of the same material as the substrate1801since a portion of the substrate1801is etched, or may be formed of a different material from the substrate1801.

As in the present embodiment, since the convex-concave structure is formed at an interface between the substrate1801and the first conductive semiconductor layer1804, a path of light emitted from the active layer1805may vary, such that a rate of light that is absorbed in the semiconductor layer may be decreased and a light-scattering rate may be increased; thus, the light extraction efficiency may be increased.

In more detail, the convex-concave structure may have a regular shape or an irregular shape. Heterogeneous materials that form the convex-concave structure may include a transparent conductor, a transparent insulator, or a material having excellent reflectivity, and in this regard, the transparent insulator may include, but is not limited to, SiO2, SiNx, Al2O3, HfO, TiO2or ZrO, the transparent conductor may include, but is not limited to, TCO such as indium oxide containing ZnO or an additive including Mg, Ag, Zn, Sc, Hf, Zr, Te, Se, Ta, W, Nb, Cu, Si, Ni, Co, Mo, Cr, or Sn, and the reflective material may include, but is not limited to, Ag, Al, or DBR that is formed of a plurality of layers having different refractive indexes.

The substrate1801may be removed from the first conductive semiconductor layer1804. In order to remove the substrate1801, a laser lift off (LLO) process using a laser, an etching process, or a grinding process may be performed. After the substrate1801is removed, the convex-concave structure may be formed on a top surface of the first conductive semiconductor layer1804.

As illustrated inFIG. 14, the light emitting device chip1810is mounted on the mounting substrate1820. The mounting substrate1820has a structure in which upper and lower electrode layers1812band1812aare formed on a top surface and a bottom surface of a substrate body1811, respectively, and a via1813penetrates through the substrate body1811so as to connect the upper and lower electrode layers1812band1812a. The substrate body1811may be formed of resin, ceramic, or metal, and the upper and lower electrode layers1812band1812amay be metal layers including Au, Cu, Ag, Al, or the like.

Obviously, an example of a substrate on which the light emitting device chip1810is mounted is not limited to the mounting substrate1820ofFIG. 14, and thus any substrate having a wiring structure to drive the light emitting device chip1810may be used. For example, it is possible to provide a package structure in which the light emitting device chip1810is mounted in a package body having a pair of lead frames.

A light emitting device chip having one of various structures may be used, other than the light emitting device chips. For example, it is possible to use a light emitting device chip having a light extraction efficiency that is significantly improved by interacting a quantum well exciton and surface-plasmon polaritons (SPP) formed at an interface between metal and dielectric layers of the light emitting device chip.

The various light emitting device chips may be mounted as bare chips on a circuit board and then may be used in the lighting apparatus. However, unlike this, the light emitting device chips may be also alternatively used in various package structures that are mounted in a package body having a pair of electrodes.

A package including the light emitting device chip (hereinafter, referred to as an light emitting device package) may have not only an external terminal structure that is easily connected to an external circuit but also may have a heat dissipation structure for improvement of a heat dissipation characteristic of the light emitting device chip and various optical structures for improvement of a light characteristic of the light emitting device chip. For example, the various optical structures may include a wavelength conversion unit that converts light emitted from the light emitting device chip into light having a different wavelength, or may include a lens structure for improvement of a light distribution characteristic of the light emitting device chip.

The example of the light emitting device package that may be used in the lighting apparatus may include a light emitting device chip package having a CSP structure.

The CSP may reduce a size of the light emitting device chip package, may simplify the manufacturing procedure, and may be appropriate for mass production. In addition, a light emitting device chip, wavelength conversion materials such as phosphors, and an optical structure such as a lens may be integrally manufactured, so that the CSP may be designed as appropriate for the lighting apparatus.

FIG. 15is a lateral cross sectional view of a light emitting device package that may be used in a light source ofFIG. 9according to an embodiment of the inventive concept.FIG. 15illustrates an example of a CSP that has a package structure in which an electrode is formed via a bottom surface of a light emitting device1910that is in an opposite direction of a primary light extraction surface, and a phosphor layer1907and a lens1920are integrally formed, according to an embodiment of the inventive concept.

A CSP1900shown inFIG. 15includes a light emitting device stack S disposed on a mounting substrate1911, first and second terminals Ta and Tb, the phosphor layer1907, and the lens1920.

The light emitting device stack S has a stack structure including first and second semiconductor layers1904and1906, and an active layer1905disposed between the first and second semiconductor layers1904and1906. In the present embodiment, the first and second semiconductor layers1904and1906may be p-type and n-type semiconductor layers, respectively, and may be formed of a nitride semiconductor such as AlxInyGa(1-x-y)N(0≦x≦1, 0≦y≦1, 0≦x+y≦1). Alternatively, the first and second semiconductor layers1904and1906may be formed of a GaAs-based semiconductor or a GaP-based semiconductor, other than the nitride semiconductor.

The active layer1905that is disposed between the first and second semiconductor layers1904and1906may emit light that has a predetermined energy due to recombination of electrons and holes and may have a MQW structure in which a quantum well layer and a quantum barrier layer are alternately stacked. The MQW structure may include an InGaN/GaN structure or a AlGaN/GaN structure.

The first and second semiconductor layers1904and1906, and the active layer1905may be formed via a semiconductor layer growing procedure such as MOCVD, MBE, HVPE, or the like that is well known in the art.

In the light emitting device1910shown inFIG. 15, a growth substrate is already removed, and a concave-convex structure P may be formed on a surface of the light emitting device1910from which the growth substrate is removed. Also, the phosphor layer1907is formed as a light conversion layer on the surface whereon the concave-convex structure P is formed.

The light emitting device1910has first and second electrodes1909aand1909bthat contact the first and second semiconductor layers1904and1906, respectively. The first electrode1909ahas a conductive via1908that contacts the first semiconductor layer1904by penetrating through the second semiconductor layer1906and the active layer1905. The conductive via1908has an insulating layer1903formed between the active layer1905and the second semiconductor layer1906, thereby preventing a short.

Referring toFIG. 15, one conductive via1908is arranged, but in another embodiment, at least two conductive vias1908may be arranged for improved current distribution and may be arrayed in various forms.

The mounting substrate1911is a supporting substrate such as a silicon substrate to be easily applied to a semiconductor procedure, but examples of the mounting substrate1911may vary. The mounting substrate1911and the light emitting device1910may be bonded to each other via bonding layers1902and1912. The bonding layers1902and1912may be formed of an electrical insulation material or an electrical conduction material, and in this regard, examples of the electrical insulation material may include oxide such as SiO2, SiN, or the like, or resin materials including a silicon resin, an epoxy resin, or the like, and examples of the electrical conduction material may include Ag, Al, Ti, W, Cu, Sn, Ni, Pt, Cr, NiSn, TiW, AuSn, or a eutectic metal thereof. The bonding process may be performed in a manner in which the bonding layers1902and1912are arranged on bonding surfaces of the light emitting device1910and the mounting substrate1911and then are bonded together.

A via that penetrates through the mounting substrate1911is formed at a bottom surface of the mounting substrate1911so as to contact the first and second electrodes1909aand1909bof the bonded light emitting device1910. Then, an insulator1913may be formed on a side surface of the via and the bottom surface of the mounting substrate1911. When the mounting substrate1911is formed as a silicon substrate, the insulator1913may be arranged as a silicon oxide layer that is formed via a thermal oxidation procedure. By filling the via with a conductive material, the first and second terminals Ta and Tb are formed to be connected to the first and second electrodes1909aand1909b. The first and second terminals Ta and Tb may include seed layers1918aand1918b, and plating charging units1919aand1919bthat are formed by using the seed layers1918aand1918bvia a plating procedure.

FIG. 16is an exploded perspective view of an L tubular lighting apparatus3000according to the embodiment of the inventive concept. Referring toFIG. 16, the L tubular lighting apparatus3000includes a heat dissipator3100, a cover3200, a light emitting module3300, a first socket3400, a second socket3500, a power supply3600, a communication interface3700, and a non-contact sensor3800.

The L tubular lighting apparatus3000is an LED lighting apparatus that replaces an existing fluorescent lamp and may have the same size as that of the existing fluorescent lamp.

A plurality of heat dissipation pins3110may be formed in a concave-convex structure on inner and/or outer surfaces of the heat dissipation member3100, and in this regard, it is possible to design the heat dissipation pins3100to have various shapes and intervals.

A diffusion material may be coated or charged in an inner surface of the cover3200so that light emitted from the light emitting module3300may well diffuse. The cover3200may be formed of a transparent plastic material, a glass material, or a translucent plastic material.

The light emitting module3300may include a PCB3310and a light emitting device array3320. The PCB33101may include circuit wirings to operate the light emitting device array3320. Configuration elements to operate the light emitting device array3320may be included in the PCB3310.

The first and second sockets3400and3500are a pair of sockets and are combined with ends of the cylindrical cover unit that is formed of the heat dissipation member3100and the cover3200.

For example, the first socket3400may include an electrode terminal3410and the power supply unit3600. A dummy terminal3510may be disposed at the second socket3500.

The power supply unit3600receives AC power (of from about 100V˜about 240V) and supplies AC or DC power suitable for a LED light source. The power supply unit3600may be integrated with the PCB3310or may be separated from another circuit substrate.

The communication interface3700and the non-contact sensor3800may be embedded in the second socket3500. The L tubular lighting apparatus3000may be connected to an external network via the communication interface3700to communicate with an external apparatus. The L tubular lighting apparatus3000may be controlled via wireless or wired communication. A user may apply an external signal such as a magnetic signal to the non-contact sensor3800such that the network may be reset.

FIG. 17is a schematic view of a flat panel lighting apparatus4000according to the embodiment of the inventive concept. The flat lighting apparatus4000may include a light source4100, a power supply4200, a housing4300, a communication interface4400, and a non-contact sensor4500.

The light source4100may form generally a planar shape as shown inFIG. 17. The power supply4200may be configured to supply power to the light source4100.

The flat panel lighting apparatus4000may be connected to a network via the communication interface4400and may be controlled via wireless or wired communication. When the network is necessarily reset, a user may apply a magnetic signal to the non-contact sensor4500. Thus, the non-contact sensor4500may generate a reset signal, and then the communication interface4400may reset the network in response to the reset signal.

The housing4300may be formed to have a space for accommodating the light source4100, the power supply4200, the communication interface4400, and the non-contact sensor4500, and may have an open hexahedral shape but is not limited thereto. The light source4100may be disposed to emit light in one open side surface of the housing4300. The non-contact sensor4500is accommodated in the housing4300in the present embodiment but is not limited thereto. The non-contact sensor4500may be mounted outside the housing4300.

FIG. 18illustrates a home network to which a lamp is applied according to an embodiment of the inventive concept. The home network provides the ability to connect electric home appliances via a wired or wireless network and mutually control the home appliances via the network, the Internet, and data sharing. Electric home appliances capable of wireless communication such as a wireless lighting apparatus5100, a TV5200, a wireless door lock5300, a home appliance5400, a smart phone5500, a home wireless router5600, a wall switch5700, or the like are connected to a gateway6000to form a network and mutually control the electric home appliances. As in-house wireless communication protocols, ZigBee, WiFi, Bluetooth, or the like may be used. Brightness of the wireless lighting apparatus5100may be automatically adjusted according to operating statuses of a sensor located on a porch, the wall switch5700, a home appliance, or the like, and ambient environments/situations.

For example, the brightness of the wireless lighting apparatus5100may be automatically adjusted according to a type of a program broadcasted on the TV5200or brightness of a screen of the TV5200. When a cozy atmosphere is required due to broadcasting of human drama, brightness may be adjusted to have a color temperature equal to or less than 12000° K according to the cozy atmosphere. When a light atmosphere is required due to broadcasting of a comedy program, brightness may be adjusted to have a color temperature equal to or greater than 12000° K and may have a blue-based white color.