KR102689971B1 - Plasma lighting device - Google Patents

Abstract

One embodiment relates to a plasma lighting device, comprising: an RF signal generator that generates an RF (Radio Frequency) signal of a set frequency; A resonator that receives and radiates the RF signal; A plasma bulb that emits light by ionizing the gas enclosed therein by the RF signal emitted from the resonator, and turning the inside into a plasma state by the ionized gas; and a shielding unit coupled to the resonator and configured to shield electromagnetic waves emitted to the outside from within the resonator.

Description

Plasma lighting device {PLASMA LIGHTING DEVICE}

The present invention relates to a plasma lighting device, and more specifically, to a plasma lighting device using radio frequency signals.

Due to various advantages such as relatively excellent energy efficiency, long lifespan, and stability, the use of LED (Light Emitting Diode) lighting is gradually increasing. However, lighting systems using LEDs inevitably suffer from flickering due to the use of LED driving drivers, can only implement specific light wavelengths according to RGB combinations, and are prone to eye fatigue due to flickering, high-speed cameras, etc. There is a problem that it turns off when using . In addition, lighting systems using LEDs have the possibility of partial defects depending on the array of LED elements, the brightness is too strong, which puts a strain on the eyes, and in the case of high-output products, there is a problem of severe deterioration due to heat generation problems.

Plasma lighting devices are being developed to solve these problems. Plasma lighting devices use the principle of emitting bright light of a specific spectrum when materials in a plasma state return to a stable state. The plasma lighting device has an emission spectrum similar to that of sunlight, but the supply of energy is different from that of sunlight. For example, the plasma bulb contains an inert gas and a metal, and by emitting radio waves to the plasma bulb, atoms in the gas mixture are ionized to form a plasma state. The plasma lighting device may further include a resonator to effectively transmit radio waves to the plasma bulb.

Meanwhile, the plasma bulb is an insulator when first turned on and gradually changes into a conductor while generating plasma, which may cause the resonant frequency of the resonator to change rapidly. Additionally, the resonant frequency may vary depending on various factors such as the surrounding environment, resonator error, and plasma bulb error. In this way, when radio waves with a fixed frequency are radiated to the plasma bulb while the resonance frequency is changed, there is a problem in which electric energy is not efficiently transmitted to the plasma bulb.

Additionally, when a plasma bulb is emitted using an RF signal, negative effects may occur due to electromagnetic waves being emitted. In addition, there is a disadvantage that separate circuits for impedance matching must be added in order to effectively transmit the generated RF signal to the resonator.

Against this background, the purpose of this embodiment is to provide a plasma lighting device that changes the frequency of the RF signal by tracking the resonant frequency that changes in real time as the lighting state of the plasma bulb changes.

Additionally, the purpose of this embodiment is to provide a plasma lighting device for shielding electromagnetic waves emitted to the outside from a resonator in the plasma lighting device and maintaining a stable plasma state.

Additionally, the purpose of this embodiment is to provide a plasma lighting device that matches impedance by adjusting the length of an RF cable that transmits an RF signal from the plasma lighting device to the resonator.

In order to achieve the above-described object, a plasma lighting device according to an embodiment includes: an RF signal generator that generates an RF (Radio Frequency) signal of a set frequency; A resonator that receives and radiates the RF signal; A plasma bulb that emits light by ionizing the gas enclosed therein by the RF signal emitted from the resonator, and turning the inside into a plasma state by the ionized gas; and a shielding unit coupled to the resonator and configured to shield electromagnetic waves emitted to the outside from within the resonator.

According to one embodiment, the shielding part forms a honeycomb mesh structure and may surround the outside of the plasma bulb.

According to one embodiment, a motor; and a shaft connected between the motor and the plasma bulb and rotating the plasma bulb according to rotation of the motor.

According to one embodiment, an RF cable transmitting an RF signal generated from the RF signal generator; and an RF connector disposed on one external side of the resonator and inputting the RF signal transmitted through the RF cable into the resonator.

According to one embodiment, the length of the RF cable may be set considering impedance matching of the RF signal.

According to one embodiment, it may include a control unit that controls the RF signal generator to change the frequency of the RF signal according to the lighting stage of the plasma bulb.

According to one embodiment, the controller may determine the resonance frequency by controlling the RF signal generator to scan a set frequency band after power is supplied to the RF signal generator and before the plasma bulb is turned on.

According to one embodiment, the control unit may determine the changed resonance frequency by controlling the RF signal generator to scan a set frequency band in response to the plasma bulb starting to light.

According to one embodiment, the control unit may control the RF signal generator to track a changing resonant frequency after the plasma bulb starts lighting until it is fully lit.

According to one embodiment, the control unit may control the RF signal generator to track the changing resonant frequency after the plasma bulb is fully turned on.

As described above, according to this embodiment, electrical energy can be efficiently transmitted to the plasma bulb by tracking the resonant frequency that changes in real time as the lighting state of the plasma bulb changes.

In addition, according to this embodiment, high frequency accuracy and fast frequency switching speed can be provided by generating an RF signal for radiation to the plasma bulb by a DDS (Direct Digital Synthesizer)-based PLL (Phase-Locked Loop), A variety of frequency and phase control functions can be provided. Accordingly, the stability of plasma lighting can be increased by effectively maintaining the plasma state even if the frequency characteristics of the resonator change depending on the lighting state of the plasma bulb or the frequency characteristics of the plasma resonator change depending on the environment (e.g. temperature or humidity). there is.

Additionally, according to this embodiment, electromagnetic waves emitted to the outside from the resonator can be shielded through the shielding part in the plasma lighting device, and a stable plasma state can be maintained.

Additionally, according to this embodiment, the impedance can be matched without a separate impedance matching circuit by adjusting the length of the RF cable that transmits the RF signal from the plasma lighting device to the resonator.

Figure 1 is a block diagram showing the detailed configuration of a plasma lighting device according to an embodiment.
Figure 2 is a block diagram showing the detailed configuration of an RF signal generator according to an embodiment.
Figure 3 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.
Figure 4 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.
Figure 5 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.
Figure 6 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.
Figure 7 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.
Figure 8 is a perspective view of a plasma lighting device according to an embodiment.
Figure 9 is a cross-sectional view of a plasma lighting device according to an embodiment.

Hereinafter, some embodiments of the present invention will be described in detail through illustrative drawings. When adding reference numerals to components in each drawing, it should be noted that identical components are given the same reference numerals as much as possible even if they are shown in different drawings. Additionally, in describing the present invention, if it is determined that a detailed description of a related known configuration or function may obscure the gist of the present invention, the detailed description will be omitted.

Additionally, when describing the components of the present invention, terms such as first, second, A, B, (a), and (b) may be used. These terms are only used to distinguish the component from other components, and the nature, sequence, or order of the component is not limited by the term. When a component is described as being “connected,” “coupled,” or “connected” to another component, that component may be directly connected or connected to that other component, but there is another component between each component. It will be understood that elements may be “connected,” “combined,” or “connected.”

Figure 1 is a block diagram showing the detailed configuration of a plasma lighting device according to an embodiment.

Referring to FIG. 1, the plasma lighting device 100 includes a control unit 110, a radio frequency (RF) signal generator 120, a power supply unit 130, an RF signal amplifier 140, a resonator 150, and a plasma It may include a light bulb 170 (or bulb). The plasma lighting device 100 may further include a motor 160.

According to one embodiment, the power supply unit 130 may supply power (eg, direct current power) to the control unit 110, the RF signal generator 120, or the RF signal amplifier 140. For example, the power supply unit 130 may be a Switching Mode Power Supply (SMPS). Additionally, the power supply unit 120 can obtain a desired direct current voltage/current using a normal commercial alternating current voltage (for example, AC 110V to 220V) or a normal direct current battery pack. Accordingly, the plasma lighting device 100 according to one embodiment can be easily installed and used not only outdoors, in vehicles and ships, but also in general homes.

According to one embodiment, the RF signal generator 120 may generate radio waves (eg, RF signals) to be radiated to the plasma bulb 170. For example, the RF signal generator 120 may receive a control signal from the controller 110 and generate an RF signal with a frequency corresponding to the control signal. The frequency of the RF signal generated by the RF signal generator 120 may be any one of the ISM (Industrial Scientific and Medical) bands of 433 MHz, 915 MHz, 2450 MHz, and 5800 MHz, but is not limited thereto. The RF signal generator 120 may generate an RF signal for radiating to the plasma bulb 170 using a Direct Digital Synthesizer (DDS)-based Phase-Locked Loop (PLL). In this way, the RF signal generator 120 can provide relatively high frequency accuracy and fast frequency switching speed by generating an RF signal by a DDS-based PLL, and can provide various frequency and phase control functions. . Accordingly, the stability of the plasma lighting device can be increased by effectively maintaining the plasma state within the plasma bulb even if the frequency characteristics of the plasma resonator change depending on the environment, such as the lighting state or temperature and humidity.

According to one embodiment, the RF signal amplifier 140 may receive an RF signal from the RF signal generator 120 and amplify it. According to one embodiment, the RF signal amplifier 140 may be implemented with an LDMOS transistor (Laterally Diffused Metal Oxide Semiconductor Field Effect Transistor), GaN transistor, GaAs transistor, InP transistor, or TWT/TWTa transistor, but is limited thereto. It doesn't work. For example, the RF signal amplifier 140 includes Monolithic Microwave Integrated Circuits (MMIC) 141, a first transistor 142 (e.g., a drive transistor, a second transistor 143, and an isolator 144). According to another embodiment, the isolator 144 of the RF signal amplifier 140 may be replaced with a coupler or a circulator. A coupler or circulator may be further added to the isolator 144. The isolator 144, a coupler, or circulator may be used to generate an incident wave of the RF signal transmitted from the RF signal amplifier 140 to the resonator 150. Alternatively, the isolator 144, coupler, or circulator may perform a function of sensing a reflected wave (eg, voltage or current of an incident wave or reflected wave) and transmitting it to the control unit 110. However, the isolator 144 may be replaced with other parts or components that can sense RF signals in addition to the isolator 144, coupler, or circulator. For convenience, the incident wave transmitted from the RF signal amplifier 144 to the resonator 150 will be referred to as a FWD (forward) signal, and the reflected wave reflected from the resonator 150 will be referred to as an RVS (reverse) signal. For example, the circulator may optimize impedance matching between the RF signal generator 120 (or RF signal amplifier 140) and the resonator 150, and the coupler may provide a protection function against reflected waves. A function for sensing an incident wave and/or a reflected wave of the RF signal may be provided.

According to one embodiment, the RF signal amplifier 140 may receive an RF signal from the RF signal generator 120, amplify it, and output it to the resonator 150. For example, the RF signal amplifier 140 may output an RF signal having a power of 30 watts to 2000 watts. The power level of the RF signal output from the RF signal amplifier 140 may be adjusted by a control signal from the control unit 110. For example, the RF signal amplifier 140 can amplify and output the input RF signal with powers of 30W, 50W, 250W, 600W, 1kW, and 1.8kW.

According to one embodiment, the RF signal output from the RF signal amplifier 140 may be transmitted through the RF cable 152. For example, one end of the RF cable 152 may be connected to the RF signal amplifier 140, and the other end may be connected to the RF connector 151. The RF signal input to the RF connector 151 may be transmitted to the resonator 150. The resonator 150 may receive the RF signal through the RF connector 151 and directly radiate the RF signal to the plasma bulb 170. The inside of the plasma bulb 170 may be in a plasma state as an RF signal is emitted from the resonator 150. Accordingly, the plasma bulb 170 may emit light. The resonator 150 may include a ceramic body that approximately surrounds the plasma bulb 170 and an antenna installed inside the ceramic body.

According to one embodiment, the plasma bulb 170 may include, but is not limited to, a quartz bulb, an inert gas, and a metal halide. The quartz bulb can be manufactured in a long oval shape, and inert gas and metal halide can be sealed inside. The inert gas may include, but is not limited to, at least one selected from the group consisting of sodium-thallium-indium-based, scandium-sodium, dysprosium-thallium-based, and tin-based. According to one embodiment, the plasma lighting device 100 directs light generated from the quartz bulb to the rear area coupled to the inside of the resonator 150 among the quartz bulbs to the front area to improve the light efficiency of the plasma bulb 170. A reflector may be further included so that everything is reflected. The plasma bulb 170 (eg, a quartz bulb) is an electrodeless system in which no electrodes exist inside the plasma bulb 170 (eg, a quartz bulb), and thus can provide a relatively long lifespan.

According to one embodiment, the control unit 110 controls the RF signal generator 120 and/or the RF signal amplifier 140 by a control signal, controlling the output frequency and/or output power of the RF signal. can do. According to one embodiment, the control unit 110 may control the RF signal generator 120 and/or the RF signal amplifier 140 to dim (adjust brightness) the plasma bulb 170.

According to one embodiment, the control unit 110 may receive a signal (eg, a reflected wave) returned from the resonator 150 through the isolator 144 (or a coupler or circulator). For example, the control unit 110 may control the RF signal amplifier 140 to output an RF signal having a frequency that minimizes the power of the RF signal returned through the resonator 150.

Meanwhile, the plasma bulb 170 is initially turned on from an insulator to a conductor while generating plasma, so the resonance frequency of the resonator 150 may change rapidly. Additionally, the resonant frequency may vary depending on various factors such as the surrounding environment, error of the resonator 150, and error of the plasma bulb 170. In this way, when the resonator 150 radiates radio waves (e.g., RF signals) with a fixed frequency to the plasma bulb 170 while the resonant frequency is changed, electrical energy is not efficiently transmitted to the plasma bulb 170. It may not be possible.

More specifically, the plasma bulb 170 may be in a state of insulators (materials with high electrical resistance) such as glass (e.g., quartz) when turned on, and applies electrical energy by emitting an RF signal (or radio wave) to A gas mixture can be converted into a plasma state. In the above process, within the plasma bulb 170, electrons in gas molecules are ionized by absorbing energy, and plasma composed of ionized particles and free electrons can be generated. At this time, since the plasma is a conductor, the electrically neutral plasma bulb 170 may become a dipole electrically separated into an anode and a cathode. Electrical energy applied to the dipole causes current to flow, heating the inside of the plasma bulb 170, and light generated from the plasma is emitted, thereby functioning as a lighting device.

As described above, according to one embodiment, the plasma bulb 170 at the initial stage of lighting changes from an insulator to a conductor while generating plasma, so that the resonant frequency of the resonator 150 may change rapidly. Additionally, it may be difficult to specify the resonant frequency due to the surrounding environment, the error range of the resonator 150, and the error range of the plasma bulb 170. In various embodiments described later, the electrical energy generated in the RF signal amplifier 140 can be efficiently transmitted into the plasma bulb 170 by tracking the rapidly changing resonance frequency at a high speed. As such, according to one embodiment, plasma generation within the plasma bulb 170 can be stably completed by applying appropriate electrical energy to the plasma bulb 170 at an appropriate time. The specific control method of the plasma lighting device 100 will be described in detail later in the description of FIGS. 3 to 7.

According to one embodiment, the motor 160 (eg, DC motor) may perform the function of rotating the plasma bulb 170. More specifically, plasma can be created by ionizing atoms in a gas mixture. In this way, when plasma is generated, ionized particles are affected by an electric field and can move by receiving force due to interaction with each other. Due to the above interaction, plasma can operate as a type of fluid. However, the plasma may be tilted to one side due to gas flow and electron transport phenomena. This may cause local heating within the plasma bulb 170 in the plasma lighting device 100, which may shorten the lifespan of the plasma bulb 170. In addition, the brightness in the direction where the plasma is focused appears relatively stronger, and the brightness becomes weaker in the opposite direction, which may affect the uniformity of the lighting and cause a decrease in the quality of the lighting. The motor 160 may serve to uniformly apply an electric field and a flow of ionized plasma within the plasma bulb 170 by rotating the plasma bulb 170 .

Figure 2 is a block diagram showing the detailed configuration of an RF signal generator according to an embodiment.

Referring to FIG. 2, the RF signal generator 120 may include a frequency generator 210 and a frequency synthesizer 220. The frequency synthesizer 220 may include a Direct Digital Synthesizer (DDS) 221 and a Phase-Locked Loop (PLL) 222. As described above, the RF signal generator 120 may generate an RF signal for radiating to the plasma bulb 170 using a Direct Digital Synthesizer (DDS)-based PLL (Phase-Locked Loop).

According to one embodiment, the frequency generator 210 may generate a reference frequency signal (f _REF ). The DDS 221 receives a reference frequency signal from the frequency generator 210 and, based on the control signal received from the control unit 110, generates a first RF signal (f _DDS ) having a frequency corresponding to the control signal. can be created. The PLL 222 may receive the output of the DDS 221 as a reference frequency and generate a second RF signal f _OUT whose phase is controlled. The second RF signal output from the PLL 222 may be transmitted to the RF signal amplifier 140.

According to one embodiment, the DDS 221 of the frequency synthesizer 220 may receive a reference frequency from the frequency generator 210, which is a reference frequency source, and output a digitally synthesized frequency. The PLL 222 can use the output of the DDS 221 as its reference frequency input. As described above, the RF signal generator 120 can provide relatively high frequency accuracy and fast frequency switching speed by generating an RF signal by a DDS-based PLL, and can provide various frequency and phase control functions. You can. Accordingly, the stability of the plasma lighting device can be increased by effectively maintaining the plasma state within the plasma bulb 170 even if the frequency characteristics of the resonator 150 change depending on the environment, such as the lighting state or temperature and humidity.

Hereinafter, with reference to FIGS. 3 to 7, the control unit 110 controls the DDS 221 and/or the PLL 222 of the RF signal generator 120 according to the lighting stage of the plasma bulb 170. By doing so, various embodiments of adjusting the frequency of the RF signal will be described.

Figure 3 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.

According to one embodiment, the plasma lighting device 100 may check the resonant frequency that changes depending on the lighting stage of the plasma bulb 170 and adjust the radio frequency signal in response to the changed resonant frequency.

According to one embodiment, the lighting stage of the plasma bulb 170 may be divided into a plurality of sections. For example, the lighting stage may be divided into a section in an unlit state after the power is turned on, a section where lighting starts, a section from when lighting starts to before lighting is completed, and a section after lighting is completed, but is not limited to this.

As described above, according to one embodiment, the plasma bulb 170 at the initial stage of lighting changes from an insulator to a conductor while generating plasma, so that the resonant frequency of the resonator 150 may change rapidly. Additionally, the resonance frequency may change in real time depending on the surrounding environment (eg, temperature or humidity, etc.). Therefore, according to various embodiments, the rapidly changing resonance frequency is tracked at a high speed by the RF signal generator 120, so that the electrical energy generated in the RF signal amplifier 140 is efficiently transmitted within the plasma bulb 170. It can be done as much as possible.

Referring to FIG. 3, when the plasma lighting device 100 is turned on, power may be supplied to the control unit 110, the RF signal generation unit 120, and the RF signal amplification unit 140. At this time, the plasma bulb 170 may be in an unlit state that has not yet been lit. As described above, the resonant frequency of the resonator may vary depending on the environment (eg, temperature or humidity) or individual errors of the resonator. Therefore, even if the plasma lighting devices 100 are manufactured with the same resonance frequency (eg, 2450 MHz), the resonance frequencies in the unlit state may be different. Accordingly, as the power is turned on, the control unit 110 can determine or confirm the resonance frequency by scanning the set frequency band (referred to as 'first scan' for convenience) (step 310). For example, a plasma lighting device. When the frequency of the RF signal for operating (100) is set to 2450 MHz, the resonance frequency can be confirmed through a frequency sweep within a frequency band (e.g., 2440 MHz to 2460 MHz) set around the frequency.

As a more specific implementation example, the control unit 110 changes the frequency generated by the RF signal generator 120 at a certain frequency interval (e.g., 100 KHz) within the set frequency band (e.g., 2440 MHz to 2460 MHz) and outputs it. The RF signal generator 120 can be controlled. That is, when the control unit 110 confirms that the power is turned on and the plasma bulb 170 is not lit, it sends a control signal (e.g., the first control signal and the second control signal of FIG. 2) to the RF signal generator ( 120). The RF signal generator 120 may change the frequency of the RF signal at regular frequency intervals within the set frequency band and output it based on the control signal. According to one embodiment, the control unit 110 may determine the frequency at which the power of the reflected wave reflected from the resonator 150 is lowest among a plurality of frequencies within the set frequency band as the resonant frequency. According to another embodiment, the control unit 110 selects a frequency at which the power of the reflected wave reflected from the resonator 150 satisfies a set condition among a plurality of frequencies within the set frequency band (e.g., a frequency at which the power of the reflected wave is less than a threshold value). can be judged as the resonance frequency.

Next, when the plasma bulb 170 is turned on over time, the resonant frequency may change according to changes in the state within the plasma bulb 170, as described above. Accordingly, as the plasma bulb 170 turns on, the control unit 110 can determine or confirm the changed resonance frequency by scanning the set frequency band (referred to as 'second scan' for convenience) (step 320). ) For example, when the control unit 110 confirms that the plasma bulb 170 is turned on, it can transmit a control signal (e.g., the first control signal and the second control signal in FIG. 2) to the RF signal generator 120. . The RF signal generator 120 may change the frequency of the RF signal at regular frequency intervals within the set frequency band and output it based on the control signal. According to one embodiment, the control unit 110 may determine the frequency at which the power of the reflected wave reflected from the resonator 150 is lowest among a plurality of frequencies within the set frequency band as the resonant frequency. According to another embodiment, the control unit 110 selects a frequency at which the power of the reflected wave reflected from the resonator 150 satisfies a set condition among a plurality of frequencies within the set frequency band (e.g., a frequency at which the power of the reflected wave is less than a threshold value). can be judged as the resonance frequency.

Next, after the plasma bulb 170 is turned on, until it is fully turned on (or fully turned on) (for convenience of explanation, it will be referred to as an 'intermediate turn on state') depending on the state change within the plasma bulb 170. The resonant frequency can be changed. For example, as described above, the plasma bulb 170 at the initial stage of lighting changes from an insulator to a conductor while generating plasma, so the resonance frequency of the resonator 150 may change rapidly. Accordingly, the control unit 110 can track (or track) the resonant frequency that changes in real time as the plasma bulb 170 progresses from initial lighting to full lighting (step 330). For example, the control unit 110 ) can track the resonance frequency in real time by repeatedly performing the above-described frequency sweep operation at regular time intervals while the intermediate lighting state is maintained.

Next, when it is confirmed that the plasma bulb 170 is fully lit (or fully lit), the resonant frequency can be monitored and adjusted (step 340). For example, as described above, the resonant frequency is determined by the environment (e.g., temperature). or humidity), so even if the plasma bulb 170 is fully turned on and in a stabilized state, the resonance frequency can be monitored and adjusted at set time intervals.

Hereinafter, with reference to FIGS. 4 to 7, specific embodiments of each of the above-described steps will be described.

Figure 4 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.

Referring to FIG. 4, the control unit 110 of the plasma lighting device 100 controls the RF signal generator 120 and the RF signal amplifier 140 while the plasma bulb 170 is not lit to generate the first power. It can be controlled to output an RF signal of a level (e.g., 50 Watt) (step 410). At this time, the control unit 110 changes the frequency of the RF signal at regular frequency intervals within the frequency band section set as described above and outputs it. The RF signal generator 120 can be controlled to do so.

According to one embodiment, the control unit 110 may scan reflected waves for a plurality of frequencies within the set frequency band (step 420). Next, the control unit 110 turns on the light based on the power of the scanned reflected wave. The resonance frequency for can be determined, and the corresponding frequency can be set as the first resonance frequency (step 430). For example, the control unit 110 sets the frequency at which the power of the reflected wave reflected from the resonator 150 is lowest as the first resonance frequency. It can be judged by frequency.

Figure 5 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.

Referring to FIG. 5, when the first resonant frequency for lighting is set as shown in FIG. 4 described above, the control unit 110 of the plasma lighting device 100 controls the plasma bulb 170 based on the set first resonant frequency. can be turned on. At this time, the control unit 110 controls the RF signal generator 120 and the RF signal amplifier 140 in a state in which the plasma bulb 170 is not lit to generate RF at a second power level (e.g., 100 Watt) for lighting. It can be controlled to output a signal. (Step 510) At this time, the control unit 110 can detect whether the plasma bulb 170 (e.g., bulb) starts lighting. (Step 520) For example, , the control unit 110 may determine that the plasma bulb 170 has started lighting when the power of the reflected wave reflected from the resonator 150 is below a set value.

According to one embodiment, when the control unit 110 detects or determines that the plasma bulb 170 has started lighting, it may scan the changed resonance frequency after turning on (step 530). For example, the control unit 110 scans the changed resonance frequency. Based on the power of the reflected wave, the resonant frequency changed after lighting can be determined and the corresponding frequency can be set as the second resonant frequency (step 540). For example, the control unit 110 may control the power of the reflected wave reflected from the resonator 150. This lowest frequency can be determined as the second resonance frequency.

Figure 6 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.

Referring to FIG. 6, when the second resonant frequency is set as shown in FIG. 5 described above, the control unit 110 of the plasma lighting device 100 fully lights the plasma bulb 170 based on the set second resonant frequency. You can do it. At this time, the control unit 110 controls the RF signal generator 120 and the RF signal amplifier 140 in a state in which the plasma bulb 170 starts lighting to set the third power level (e.g., 250 Watt) for complete lighting. It can be controlled to output an RF signal (step 610). At this time, the control unit 110 can track the resonant frequency that changes as the plasma bulb 170 (eg, bulb) gradually turns on. (620 steps)

According to one embodiment, when it is confirmed that the plasma bulb 170 is fully lit (or fully lit), the control unit 110 may track the rapidly changing resonance frequency (step 630). For example, the control unit 110 ) can determine the changed resonance frequency after complete lighting based on the power of the scanned reflected wave and set that frequency as the resonance frequency.

Figure 7 is a flowchart showing a control procedure of a plasma lighting device according to an embodiment.

Referring to FIG. 7, the control unit 110 of the plasma lighting device 100 can check whether the resonance frequency is stabilized when fully illuminated as shown in FIG. 6 (step 710). For example, in FIG. As a result of the resonance frequency tracking in Figure 6, if the resonance frequency does not change anymore, it can be judged to be in a stabilized state. In this way, when it is determined that the resonance frequency is stabilized in the fully lit state, control can be made to output an RF signal at a fourth power level (e.g., 550 Watt) to maintain the fully lit state (step 720).

According to one embodiment, the control unit 110 may track the resonant frequency that is slightly changed according to changes in the environment (eg, temperature or humidity) after the resonant frequency is stabilized in a fully lit state. At this time, the control unit 110 can adjust the scanning period for the resonance frequency to be longer since the resonance frequency is stabilized. Additionally, the frequency band for tracking the resonance frequency can be set to a relatively narrow band.

As described above, according to the present embodiment, the resonant frequency, which changes as the lighting state of the plasma bulb 170 changes, is tracked in real time according to the control signal of the controller 110, thereby transmitting electrical energy to the plasma bulb 170. It can be delivered efficiently.

In addition, according to this embodiment, an RF signal for radiating to the plasma bulb 170 is generated by the DDS 221 and the PLL 222 included in the RF signal generator 120, thereby achieving high frequency accuracy and fast frequency switching. It can provide speed. That is, the resonant frequency that changes in real time during the plasma lighting stage can be quickly tracked by the DDS 221 and PLL 222. Accordingly, the stability of plasma lighting is achieved by effectively maintaining the plasma state even if the frequency characteristics of the resonator change depending on the lighting state of the plasma bulb 170 or the frequency characteristics of the plasma resonator change depending on the environment (e.g., temperature or humidity). can increase.

FIG. 8 is a perspective view of a plasma lighting device according to an embodiment, and FIG. 9 is a cross-sectional view of a plasma lighting device according to an embodiment.

Referring to FIGS. 8 and 9 , a plasma lighting device according to an embodiment may include a resonator 150 and a shield 180. The resonator 150 and the shield 180 can be combined with each other to form a housing (or body) of a plasma lighting device. As shown in FIG. 9, a plasma bulb 170 may be placed inside the housing.

According to one embodiment, an RF connector 151 may be placed on one external side of the resonator 150. The RF connector 151 may be connected to the RF signal generator 120 or the RF signal amplifier 140 and the RF cable 152. For example, as described above, the RF signal output from the RF signal amplifier 140 is input to the RF connector 151 through the RF cable 152, and is transmitted to the resonator 150 through the RF connector 151. It can be. The resonator 150 may receive an RF signal transmitted from the RF signal amplifier 140 through the RF connector 151 and directly radiate the received RF signal to the plasma bulb 170. The inside of the plasma bulb 170 may be in a plasma state as an RF signal is emitted from the resonator 150. Accordingly, the plasma bulb 170 may emit light. The length of the RF cable 152 may be set considering impedance matching of the RF signal. For example, the RF cable 152 and the RF connector 151 may be designed considering 50Ω impedance matching. Accordingly, the plasma lighting device does not need to add a separate circuit for impedance matching.

According to one embodiment, the shield 180 is combined with the resonator 150 and can shield electromagnetic waves emitted to the outside within the resonator 150. For example, the shielding unit 180 may form a honeycomb mesh structure as shown in FIG. 8, but is not limited to this form. The shielding portion 180 forming the honeycomb mesh structure may surround the outside of the plasma bulb and form a housing together with the resonator 150.

According to one embodiment, as shown in FIG. 8, a motor 160 may be fastened to the top of the resonator 150. The motor 160 may be connected to the plasma bulb 170 through a shaft 171. Accordingly, when the motor 160 rotates, the shaft 171 connected to the motor 160 rotates and the plasma bulb 170 may rotate together. For example, as described above, plasma may be tilted to one side due to gas flow and electron transport phenomena. This may cause local heating within the plasma bulb 170, which may shorten the lifespan of the plasma bulb 170. In addition, the brightness in the direction where the plasma is focused appears relatively stronger, and the brightness becomes weaker in the opposite direction, which may affect the uniformity of the lighting and cause a decrease in the quality of the lighting. Accordingly, the motor 160 may rotate the plasma bulb 170 so that the electric field and the flow of ionized plasma are uniformly applied within the plasma bulb 170.

As described above, according to this embodiment, electromagnetic waves emitted to the outside from the resonator can be shielded through the shielding part in the plasma lighting device, and a stable plasma state can be maintained. Additionally, according to this embodiment, the impedance can be matched without a separate impedance matching circuit by adjusting the length of the RF cable that transmits the RF signal from the plasma lighting device to the resonator.

Terms such as “include,” “comprise,” or “have,” as used above, mean that the corresponding component may be included, unless specifically stated to the contrary, and do not exclude other components. It should be interpreted that it may further include other components. All terms, including technical or scientific terms, unless otherwise defined, have the same meaning as generally understood by a person of ordinary skill in the technical field to which the present invention pertains. Commonly used terms, such as terms defined in a dictionary, should be interpreted as consistent with the meaning in the context of the related technology, and should not be interpreted in an idealized or overly formal sense unless explicitly defined in the present invention.

The above description is merely an illustrative explanation of the technical idea of the present invention, and those skilled in the art will be able to make various modifications and variations without departing from the essential characteristics of the present invention. Accordingly, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention, but are for illustrative purposes, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be interpreted in accordance with the claims below, and all technical ideas within the equivalent scope should be construed as being included in the scope of rights of the present invention.

100: plasma lighting device 110: control unit
120: RF signal generator 130: Power supply unit
140: RF signal amplifier 150: resonator
160: motor 170: plasma bulb
180: shielding part

Claims (10)

An RF signal generator that generates an RF (Radio Frequency) signal of a set frequency;
A resonator that receives and radiates the RF signal;
A plasma bulb that emits light by ionizing the gas enclosed therein by the RF signal emitted from the resonator, and turning the inside into a plasma state by the ionized gas;
A shielding unit coupled to the resonator and configured to shield electromagnetic waves emitted to the outside from within the resonator;
an RF cable transmitting the RF signal generated from the RF signal generator;
an RF connector disposed on one external side of the resonator and inputting the RF signal transmitted through the RF cable into the resonator; and
A control unit that controls the RF signal generator to change the frequency of the RF signal according to the lighting stage of the plasma bulb,
The length of the RF cable is set considering impedance matching of the RF signal,
The control unit,
A plasma lighting device that determines a resonance frequency by controlling the RF signal generator to scan a set frequency band after power is supplied to the RF signal generator and before the plasma bulb is turned on. The method of claim 1, wherein the shielding unit,
A plasma lighting device that forms a honeycomb mesh structure and surrounds the outside of the plasma bulb. According to paragraph 1,
motor; and
A plasma lighting device further comprising a shaft connected between the motor and the plasma bulb and rotating the plasma bulb according to rotation of the motor. delete delete delete delete An RF signal generator that generates an RF (Radio Frequency) signal of a set frequency;
A resonator that receives and radiates the RF signal;
A plasma bulb that emits light by ionizing the gas enclosed therein by the RF signal emitted from the resonator, and turning the inside into a plasma state by the ionized gas;
A shielding unit coupled to the resonator and configured to shield electromagnetic waves emitted to the outside from within the resonator;
an RF cable transmitting the RF signal generated from the RF signal generator;
an RF connector disposed on one external side of the resonator and inputting the RF signal transmitted through the RF cable into the resonator; and
A control unit that controls the RF signal generator to change the frequency of the RF signal according to the lighting stage of the plasma bulb,
The length of the RF cable is set considering impedance matching of the RF signal,
The control unit,
A plasma lighting device that determines a changed resonance frequency by controlling the RF signal generator to scan a set frequency band in response to the plasma bulb starting to light. An RF signal generator that generates an RF (Radio Frequency) signal of a set frequency;
A resonator that receives and radiates the RF signal;
A plasma bulb that emits light by ionizing the gas enclosed therein by the RF signal emitted from the resonator, and turning the inside into a plasma state by the ionized gas;
A shielding unit coupled to the resonator and configured to shield electromagnetic waves emitted to the outside from within the resonator;
an RF cable transmitting the RF signal generated from the RF signal generator;
an RF connector disposed on one external side of the resonator and inputting the RF signal transmitted through the RF cable into the resonator; and
A control unit that controls the RF signal generator to change the frequency of the RF signal according to the lighting stage of the plasma bulb,
The length of the RF cable is set considering impedance matching of the RF signal,
The control unit,
A plasma lighting device that controls the RF signal generator to track a resonant frequency that changes after the plasma bulb starts lighting until it is fully lit. An RF signal generator that generates an RF (Radio Frequency) signal of a set frequency;
A resonator that receives and radiates the RF signal;
A plasma bulb that emits light by ionizing the gas enclosed therein by the RF signal emitted from the resonator, and turning the inside into a plasma state by the ionized gas;
A shielding unit coupled to the resonator and configured to shield electromagnetic waves emitted to the outside from within the resonator;
an RF cable transmitting the RF signal generated from the RF signal generator;
an RF connector disposed on one external side of the resonator and inputting the RF signal transmitted through the RF cable into the resonator; and
A control unit that controls the RF signal generator to change the frequency of the RF signal according to the lighting stage of the plasma bulb,
The length of the RF cable is set considering impedance matching of the RF signal,
The control unit,
A plasma lighting device that controls the RF signal generator to track a changing resonance frequency after the plasma bulb is fully illuminated.