Patent Application
20250142027
This application claims the priority benefit of China application serial no. 202311388330.8 filed on Oct. 25, 2023. The entirety of the above-mentioned patent application is hereby incorporated by reference herein and made a part of this specification.
The disclosure relates to a display device, and particularly, to a projection device and a light source system thereof.
Generally, the projector includes three drive circuits to respectively drive a red (R) light source, a green (G) light source, and a blue (B) light source in a light source module. When additional light source modules are added to increase brightness, it will be required to correspondingly add drive circuits. For example, one light source module including three light sources such as a red light source, a green light source, and a blue light source requires three drive circuits for driving. If the quantity of light source modules is increased to two, then six drive circuits are required for driving. This will increase the area of the circuit board or the volume of the product, complicate the circuit, and also increase the manufacturing cost of the product.
The information disclosed in this Background section is only for enhancement of understanding of the background of the described technology and therefore it may contain information that does not form the prior art that is already known to a person of ordinary skill in the art. Further, the information disclosed in the Background section does not mean that one or more problems to be resolved by one or more embodiments of the disclosure were acknowledged by a person of ordinary skill in the art.
A light source system of a projection device according to the disclosure is configured to provide an illumination beam. The light source system includes a light source module, a driver, and a control circuit. The light source module includes a first light source, a second light source, and a third light source. The first light source, the second light source, and the third light source are respectively configured to provide a first beam, a second beam, and a third beam. The first beam, the second beam, and the third beam have wavelength ranges different from each other. The driver is coupled to the light source module and is configured to drive the light source module. The control circuit is coupled to the driver and outputs a pulse width modulation signal to the driver according to a selection signal. The pulse width modulation signal is one of a first pulse width modulation signal, a second pulse width modulation signal, and a third pulse width modulation signal received by the control circuit. The driver drives one of the first light source, the second light source, and the third light source that corresponds to the selection signal with the pulse width modulation signal. The illumination beam includes one of the first beam, the second beam, and the third beam.
A projection device according to the disclosure includes a light source system, at least one light valve, and a projection lens. The light source system is configured to provide an illumination beam. The light valve is arranged on a transmission path of the illumination beam from the light source system and is configured to convert the illumination beam into an image beam. The projection lens is arranged on a transmission path of the image beam and is configured to project the image beam out of the projection device. The light source system includes a light source module, a driver, and a control circuit. The light source module includes a first light source, a second light source, and a third light source. The first light source, the second light source, and the third light source are respectively configured to provide a first beam, a second beam, and a third beam. The first beam, the second beam, and the third beam have wavelength ranges different from each other. The driver is coupled to the light source module and is configured to drive the light source module. The control circuit is coupled to the driver and outputs a pulse width modulation signal to the driver according to a selection signal. The pulse width modulation signal is one of a first pulse width modulation signal, a second pulse width modulation signal, and a third pulse width modulation signal received by the control circuit. The driver drives one of the first light source, the second light source, and the third light source that corresponds to the selection signal with the pulse width modulation signal. The illumination beam includes one of the first beam, the second beam, and the third beam.
Other objectives, features and advantages of the disclosure will be further understood from the further technological features disclosed by the embodiments of the disclosure wherein there are shown and described preferred embodiments of the disclosure, simply by way of illustration of modes best suited to carry out the disclosure.
It is to be understood that other embodiments may be utilized and structural changes may be made without departing from the scope of the disclosure. Also, it is to be understood that the phraseology and terminology used herein are for the purpose of description and should not be regarded as limiting. The use of “including,” “comprising,” or “having” and variations thereof herein is meant to encompass the items listed thereafter and equivalents thereof as well as additional items. Unless limited otherwise, the terms “connected,” “coupled,” and “mounted,” and variations thereof herein are used broadly and encompass direct and indirect connections, couplings, and mountings.
The disclosure provides a projection device and a light source system thereof capable of effectively avoiding an increase in the area of a circuit board or the volume of a product, simplifying the circuit, and thus reducing the manufacturing cost of the product. Other objectives and advantages of the disclosure may be further learned from the technical features disclosed herein.
Further, as shown in
The driver 204 is configured to drive the light source module 206. According to a selection signal SL1, the control circuit 202 may select one of a first pulse width modulation signal PWMR, a second pulse width modulation signal PWMG, and a third pulse width modulation signal PWMB as a pulse width modulation signal PWM to be outputted to the driver 204. The selection signal SL1 may be provided by a processor of the projection device 100 such as a DLP data processor (DDP), but the disclosure is not limited thereto. The driver 204 may drive the light source corresponding to the selection signal SL1 (i.e., one of the first light source 208, the second light source 210, and the third light source 212) with the pulse width modulation signal PWM from the control circuit 202. For example, if the pulse width modulation signal and the light source corresponding to the selection signal SL1 are respectively the second pulse width modulation signal PWMG and the second light source 210, according to the selection signal SL1, the control circuit 202 may select to output the second pulse width modulation signal PWMG as the pulse width modulation signal PWM, and the driver 204 may drive the second light source 210 with the pulse width modulation signal PWM.
In this manner, with the control circuit 202 and the driver 204 switching the light source to be driven according to the selection signal SL1, it is possible to respectively drive the first light source 208, the second light source 210, and the third light source 212 in the light source module 206 by using one driver 204 coupled to the light source module 206. Thus, it is possible to reduce the quantity of drivers or drive circuits used, effectively avoid an increase in the area of the circuit board or the volume of the product, simplify the circuit, and thus reduce the manufacturing cost of the product.
Specifically, an implementation of the light source system 102 may be as shown in
The logic circuit 304 is configured to receive the selection signal SL1 and generate a first enable signal ENR, a second enable signal ENG, and a third enable signal ENB according to the selection signal SL1. The multiplexer 302 is coupled to the logic circuit 304 and may select one of the first pulse width modulation signal PWMR, the second pulse width modulation signal PWMG, and the third pulse width modulation signal PWMB as the pulse width modulation signal PWM according to the first enable signal ENR, the second enable signal ENG, and the third enable signal ENB, and output the pulse width modulation signal PWM to the drive circuit 306 of the driver 204. The selection signal SL1 may be sent by the processor of the projection device and may be, for example, a two-bit control signal. In this embodiment, the signals may be, for example, as shown in Table 1 and Table 2 below, but the disclosure is not limited thereto.
Table 1 is a table showing voltage levels of the first enable signal ENR, the second enable signal ENG, and the third enable signal ENB corresponding to the selection signal SL1.
Table 2 is a table showing voltage levels of the first enable signal ENR, the second enable signal ENG, and the third enable signal ENB corresponding to the pulse width modulation signal PWM.
When the selection signal SL1 is “0” and “0”, the logic circuit 304 may correspondingly output the first enable signal ENR, the second enable signal ENG, and the third enable signal ENB at the low voltage level, and at this time, the multiplexer 302 does not output the pulse width modulation signal PWM. When the selection signal SL1 is “0” and “1”, the logic circuit 304 may correspondingly output the first enable signal ENR at the high voltage level and the second enable signal ENG and the third enable signal ENB at the low voltage level. The multiplexer 302 may then select the first pulse width modulation signal PWMR as the pulse width modulation signal PWM according to the first enable signal ENR at the high voltage level. Similarly, when the selection signal SL1 is “1” and “0” and when the selection signal SL1 is “1” and “1”, the logic circuit 304 may respectively correspondingly output the second enable signal ENG and the third enable signal ENB at the high voltage level. The multiplexer 302 may select the second pulse width modulation signal PWMG and the third pulse width modulation signal PWMB as the pulse width modulation signal PWM respectively according to the second enable signal ENG and the third enable signal ENB at the high voltage level.
The drive circuit 306 may receive the pulse width modulation signal PWM provided by the multiplexer 302 of the control circuit 202, and drive the red light source R1, the green light source G1, or the blue light source B1 in the light source module 206 with the pulse width modulation signal PWM. Furthermore, the switching circuit 308 is coupled to the drive circuit 306 and the logic circuit 304, and may switch the connection of the drive circuit 306 to one of the first light source 208 (i.e., the red light source R1), the second light source 210 (i.e., the green light source G1), and the third light source 212 (i.e., the blue light source B1) according to the first enable signal ENR, the second enable signal ENG, and the third enable signal ENB from the logic circuit 304, to thus cause the drive circuit 306 to output the pulse width modulation signal PWM to one of the first light source 208 (i.e., the red light source R1), the second light source 210 (i.e., the green light source G1), and the third light source 212 (i.e., the blue light source B1) that corresponds to the selection signal SL1 to perform driving. In addition, one terminal of the smoothing circuit 310 is coupled to the switching circuit 308 and the light source module 206 to smooth the voltage outputted by the switching circuit 308 and stabilize emission of light of the first light source 208 (i.e., the red light source R1), the second light source 210 (i.e., the green light source G1), and the third light source 212 (i.e., the blue light source B1). In some embodiments, it is also possible that the driver 204 does not include the smoothing circuit 310.
Furthermore, the switching circuit 308 may include, for example, a first switch MR1, a second switch MG1, and a third switch MB1. The first switch MR1 is coupled between the drive circuit 306 and the first light source 208 (i.e., the red light source R1), the second switch MG1 is coupled between the drive circuit 306 and the second light source 210 (i.e., the green light source G1), and the third switch MB1 is coupled between the drive circuit 306 and the third light source 212 (i.e., the blue light source B1). The conducting states of the first switch MR1, the second switch MG1, and the third switch MB1 are respectively controlled by the first enable signal ENR, the second enable signal ENG, and the third enable signal ENB outputted by the logic circuit 304. By conducting one of the first switch MR1, the second switch MG1, and the third switch MB1, the connection of the drive circuit 306 is switched to one of the first light source 208 (i.e., the red light source R1), the second light source 210 (i.e., the green light source G1), and the third light source 212 (i.e., the blue light source B1). For example, when the first enable signal ENR is at the high voltage level, the first switch MR1 is controlled by the first enable signal ENR and is turned to conducting state, and the second switch MG1 and the third switch MB1 remain in non-conducting state, so the connection of the drive circuit 306 can be switched to the first light source 208 (i.e., the red light source R1). At this time, by switching the conduction in this manner, the pulse width modulation signal PWM provided by the multiplexer 302 to the drive circuit 306 can be further outputted to the first light source 208 (i.e., the red light source R1) to perform driving and light up the red solid-state lighting electronic components in the light source module 206.
In addition, the smoothing circuit 310 may include a first capacitor CR1, a second capacitor CG1, and a third capacitor CB1. The first capacitor CR1 is coupled between the first switch MR1 and the ground voltage, the second capacitor CG1 is coupled between the second switch MG1 and the ground voltage, and the third capacitor CB1 is coupled between the third switch MB1 and the ground voltage. The first capacitor CR1, the second capacitor CG1, and the third capacitor CB1 may be respectively configured to smooth the voltages provided by the first switch MR1, the second switch MG1, and the third switch MB1. Specifically, the first capacitor CR1, the second capacitor CG1, and the third capacitor CB1 mainly serve to reduce a current ripple. Meanwhile, when any one of the first switch MR1, the second switch MG1, and the third switch MB1 is in non-conducting state, if there is still current in the corresponding circuit that has not been completely discharged, the corresponding light source (e.g., one of the first light source 208, the second light source 210, and the third light source 212) may emit light while it should be off. Considering the above, the corresponding capacitance values may be designed respectively according to the quantities of solid-state lighting electronic components used in the first light source 208, the second light source 210, and the third light source 212. In this embodiment, the first light source 208 includes four red laser diodes, the second light source 210 includes two blue laser diodes, and the third light source 212 includes three green laser diodes. The capacitance value of the first capacitor CR1 may be 5 μF to 8 μF, the capacitance value of the second capacitor CG1 may be 3 μF to 6 μF, and the capacitance value of the third capacitor CB1 may be 8 μF to 11 μF.
In other embodiments, the control circuit 202 may further include an OR gate and a non-inverting amplifier. For example, in the embodiment shown in
The OR gate 402 may enable the multiplexer 302 according to the first enable signal ENR, the second enable signal ENG, and the third enable signal ENB. For example, when any one of the first enable signal ENR, the second enable signal ENG, and the third enable signal ENB is at the high voltage level, the OR gate 402 outputs, via the output terminal Y, the enable signal at the high voltage level to the enable input terminal EN of the multiplexer 302 to enable the multiplexer 302. According to the first enable signal ENR and the second enable signal ENG respectively received by the selection input terminals A0 and A1, the multiplexer 302 may select one of the first pulse width modulation signal PWMR, the second pulse width modulation signal PWMG, and the third pulse width modulation signal PWMB as the pulse width modulation signal PWM to be outputted. For example, when the first enable signal ENR and the second enable signal ENG respectively received by the selection input terminals A0 and A1 of the multiplexer 302 are both at the low voltage level, the third pulse width modulation signal PWMB is outputted. When the first enable signal ENR received by the selection input terminal A0 of the multiplexer 302 is at the high voltage level and the second enable signal ENG received by the selection input terminal A1 is at the low voltage level, the first pulse width modulation signal PWMR is outputted. When the first enable signal ENR received by the selection input terminal A0 of the multiplexer 302 is at the low voltage level and the second enable signal ENG received by the selection input terminal A1 is at the high voltage level, the second pulse width modulation signal PWMG is outputted. However, the disclosure is not limited thereto. The function of the non-inverting amplifier 404 is to isolate the circuit to prevent resistances of the front-end circuit and the back-end circuit from affecting each other and thus affecting the voltage value accuracy of the pulse width modulation signal PWM and to reduce noise at the same time. The non-inverting amplifier 404 may amplify the pulse width modulation signal PWM provided by the multiplexer 302 and provide to the drive circuit 306 of the driver 204.
The above embodiment has been described with the light source system including one light source module as an example. However, in other embodiments, the light source system may also include a plurality of light source modules. For example, as shown in
In summary of the above, the control circuit of the disclosure selects to output one of the first pulse width modulation signal, the second pulse width modulation signal, and the third pulse width modulation signal according to the selection signal, and the driver drives the light source corresponding to the selection signal with the pulse width modulation signal provided by the control circuit. In this manner, with the control circuit and the driver switching the light source to be driven according to the selection signal, it is possible to effectively avoid an increase in the area of the circuit board or the volume of the product, simplify the circuit, and thus reduce the manufacturing cost of the product.
The foregoing description of the exemplary embodiments of the disclosure has been presented for purposes of illustration and description. It is not intended to be exhaustive or to limit the disclosure to the precise form or to exemplary embodiments disclosed. Accordingly, the foregoing description should be regarded as illustrative rather than restrictive. Obviously, many modifications and variations will be apparent to practitioners skilled in this art. The embodiments are chosen and described in order to best explain the principles of the disclosure and its best mode practical application, thereby to enable persons skilled in the art to understand the disclosure for various embodiments and with various modifications as are suited to the particular use or implementation contemplated. It is intended that the scope of the disclosure be defined by the claims appended hereto and their equivalents in which all terms are meant in their broadest reasonable sense unless otherwise indicated. Therefore, the term “the disclosure”, “the present invention” or the like does not necessarily limit the claim scope to a specific embodiment, and the reference to particularly preferred exemplary embodiments of the disclosure does not imply a limitation on the disclosure, and no such limitation is to be inferred. The disclosure is limited only by the spirit and scope of the appended claims. Moreover, these claims may refer to use “first”, “second”, etc. following with noun or element. Such terms should be understood as a nomenclature and should not be construed as giving the limitation on the number of the elements modified by such nomenclature unless specific number has been given. The abstract of the disclosure is provided to comply with the rules requiring an abstract, which will allow a searcher to quickly ascertain the subject matter of the technical disclosure of any patent issued from the disclosure. It is submitted with the understanding that it will not be used to interpret or limit the scope or meaning of the claims. Any advantages and benefits described may not apply to all embodiments of the disclosure. It should be appreciated that variations may be made in the embodiments described by persons skilled in the art without departing from the scope of the disclosure as defined by the following claims. Moreover, no element and component in the present disclosure is intended to be dedicated to the public regardless of whether the element or component is explicitly recited in the following claims.
| Number | Date | Country | Kind |
|---|---|---|---|
| 202311388330.8 | Oct 2023 | CN | national |
