The control method of optical projection system and cooling unit thereof
Technical field
The present invention is meant a kind of control method of cooling unit of optical projection system especially about a kind of control method of optical projection system.
Background technology
Flourish along with the projection display technique application market, its development trend just strides forward towards targets such as miniaturization, high brightness and low noises, wherein, is main main points on it is used to present bright image again.In order to present bright image, optical projection system must be used high-intensity light source.Be applied to the bulb of the light source of optical projection system at present, be mainly high-intensity gas discharge lamp (HID, High-intensityDischarge Lamp), for example: metal halide lamp (MHL, Metal Halide Lamp), ultrahigh pressure mercury lamp (UHP, Ultra High Pressure Mercury Lamp) and xenon arc lamp (XenonArc Lamp) etc.
The aforementioned various bulb that is applied to projection light source all has high operating temperature.With the ultrahigh pressure mercury lamp is example, has 200 atmospheric internal pressures when it is lighted approximately, and has the operating temperature of 1000 degree Celsius.Heat dissipation design that hence one can see that is to the importance of optical projection system.Therefore, when optical projection system operates, must be simultaneously by cooling units such as fans, take away the heat that each element produced that inside comprises bulb, beginning can make the optical projection system inner sustain at a certain temperature, and then makes each element be able to operate as normal, keeps the usefulness of optical projection system.
At this operating characteristic of these projection light sources is discussed further.With the ultrahigh pressure mercury lamp is example, at first produces plasma arc between two electrodes, and makes the liquid mercury evaporation in this bulb and emit forceful rays, so that required brightness to be provided.It should be noted that because steam mercury is not effective conductive media this bulb must be cooled to below the boiling point (450 degree approximately Celsius) of mercury, that is waits for when the steam mercury condensation becomes liquid, just may form electric arc to light bulb between two electrodes.Therefore, being lighted and arrive operating temperature (being generally 1000 degree Celsius) when mercury lamp when afterwards being shut down, can't be lighted at once.Must the " wait " light temperature be cooled to below the uniform temperature, the beginning can light once more.
At present general optical projection system is often kept cooling unit continuous running one such as fan fixing cool time after being turned off, the heat that produces when taking away the optical projection system running, and then cool off bulb.The purpose of this program when also starting optical projection system once more in order to ensure the user simultaneously, can be lighted bulb except preventing the bulb explosion smoothly.Yet the heat dissipation of optical projection system is provided with environment with it closely bound up, and for instance, suspention is sealed in the optical projection system of ceiling, and its heat dissipation certainly will be inferior to the optical projection system that is in open environment.Therefore, in the not good environment of heat dissipation, optical projection system light a lamp the failure situation always be difficult to avoid.
So this case inventor proposes the present invention in view of the shortcoming of above-mentioned known technology.The present invention is by detecting the situation of lighting a lamp of optical projection system, automatically the correction cooling unit is for the cool time of optical projection system, therefore, can be at its actual environment that is provided with, dynamically adjust best cool time,, and then prolong bulb life with the lifting success ratio of lighting a lamp, simultaneously, also can reduce the stand-by period that the user pays because of the failure of lighting a lamp.
Summary of the invention
The situation that fundamental purpose of the present invention avoids optical projection system to light a lamp and fail with the prolongation bulb life, and reduces the stand-by period that the user pays because of the failure of lighting a lamp.
The present invention discloses a kind of control method of cooling unit of optical projection system.After the luminescence unit of optical projection system was finished using and it is extinguished, cooling unit carried out the cooling of a schedule time to optical projection system.Subsequently, when optical projection system is started once more, detect luminescence unit and whether lighted.When luminescence unit is lighted failure, promptly prolong this schedule time.
According to this cooling means, the present invention also provides a kind of optical projection system.This optical projection system has a luminescence unit, a cooling unit and a control module.Wherein, cooling unit is in order to cool off this optical projection system, especially luminescence unit.Whether control module is connected to luminescence unit, exports a drive luminescence unit, and receive the response of selfluminous cell successfully to be lighted to detect luminescence unit.In addition, control module also is connected to cooling unit, and output one cooling control signal control cooling unit is to the cool time of optical projection system.
About of the present invention, can be further understood by following detailed description and accompanying drawings.
Description of drawings
Fig. 1 is the block schematic diagram of optical projection system one preferred embodiment of the present invention;
Fig. 2 is the control method that the present invention is directed to the cooling unit of optical projection system, the process flow diagram of a preferred embodiment;
Fig. 3 is the control method that the present invention is directed to the cooling unit of optical projection system, the process flow diagram of another preferred embodiment;
Fig. 4 is the control method that the present invention is directed to the cooling unit of optical projection system, the process flow diagram of another preferred embodiment;
Fig. 5 is the synoptic diagram of cooling unit one preferred embodiment of the present invention;
Fig. 6 is the synoptic diagram of control module one preferred embodiment of the present invention; And
Fig. 7 is the synoptic diagram of another preferred embodiment of control module of the present invention.
The main element symbol description
Optical projection system 10
Luminescence unit 12
Cooling unit 14
Control module 16
Fan 142
Fan drive circuit 144
Optical sensor 162
Voltage or current detector 164
Drive signal D
Response signal R
Cooling control signal C
Embodiment
Please refer to shown in Figure 1ly, be the block schematic diagram of optical projection system 10 1 preferred embodiments of the present invention.As shown in FIG., this optical projection system 10 has a luminescence unit 12, a cooling unit 14 and a control module 16.This optical projection system 10 can be a digital image projector or a lcd projection tv.This luminescence unit 12 can be a metal halide lamp (Metal Halide Lamp), a ultrahigh pressure mercury lamp (Ultra HighPressure Mercury Lamp) or an xenon arc lamp (Xenon Arc Lamp).Wherein, the luminescence unit 12 of cooling unit 14 in order to cool off this optical projection system 10, especially high temperature.Whether control module 16 is connected to luminescence unit 12, exports a drive signal D driven for emitting lights unit 12, and receives the response signal R of selfluminous cell 12, successfully lighted to detect luminescence unit 12.In addition, control module 16 also is connected to cooling unit 14, the cool time of 14 pairs of optical projection systems 10 of output one cooling control signal C control cooling unit.It should be noted that when optical projection system 10 and finish using, and after will luminescence unit 12 wherein extinguishing that control module 16 promptly utilizes this cooling control signal C to control 14 pairs of these optical projection systems 10 of cooling unit to carry out the cooling of a schedule time T.
Please refer to shown in Figure 2ly simultaneously, be used for the control method of the cooling unit of Fig. 1, the process flow diagram of a preferred embodiment.After the user starts optical projection system 10 (step 100), shown in step 105, light luminescence unit 12 immediately.Whether next, shown in step 110, control module 16 is used to the response signal R of selfluminous cell 12, detect luminescence unit 12 and lighted.When luminescence unit 12 was lighted successfully, shown in step 140, it was schedule time T that control module 16 is promptly kept cool time.Subsequently, after optical projection system 10 was finished using and extinguished luminescence unit 12, cooling unit 14 promptly cooled off luminescence unit 12 with this schedule time T.When luminescence unit 12 is lighted failure, shown in step 120, control module 16 promptly prolongs aforementioned cool time (T extends to T ' by the schedule time), cooling unit 14 promptly with this cool time T ' to luminescence unit 12 cooling, repeat to light this luminescence unit 12 (step 105) again.If light step through this, luminescence unit 12 is successfully lighted, and control module 16 is promptly kept the T ' cool time after this prolongation.In other words, when starting optical projection system 10, extend to T ' by T default cool time next time.
Basically, be set with a cool time and time expand interval t in this control module 16.Step 120 is not successfully lighted when control module 16 detects luminescence unit 12 as described above, and control module can be according to time expand t at interval, with cool time by schedule time T be extended for T ' (T '=T+t).Again, hence one can see that, if luminescence unit 12 experience secondaries are lighted failure, then then can be extended to T '=T+2t the cool time that sets in the control module 16.
In addition, slowly can't light, cause unconfined prolongation cool time, and cause the waste of running time, even influence the life-span of luminescence unit 12 for fear of luminescence unit 12.As shown in Figure 3, in step 120, after the step that promptly prolongs cool time (extended to T ' by T cool time), shown in step 160, judge whether the T ' cool time after this prolongation surpasses a upper limit T
LShown in step 170, the T ' cool time after prolonging does not surpass this upper limit T
LThe time, cooling unit 14 promptly can be after optical projection system be finished using, and T ' cools off luminescence unit 12 with cool time.And when starting optical projection system 10, be extended for T ' default cool times in the control module 16 next time.And shown in step 180, T cool time after prolonging " above this upper limit T
LThe time, then no longer continue cool time to prolong, and keep one cool time T '.In this case, cooling unit 14 promptly can be after optical projection system be finished using, and T ' cools off luminescence unit 12 with cool time.And when starting optical projection system 10, be maintained T ' default cool times in the control module 16 next time.
Utilizing the postboost time cooling of the optical projection system luminescence unit except aforementioned, as shown in Figure 4, in another embodiment of control method of the present invention, then is the time cooling luminescence unit that utilizes after optical projection system is started shooting.As shown in FIG., accept the step 110 of Fig. 1, shown in step 220,, promptly in control module 16, start a function, with the cooling step after the control cooling unit startup 14 next time optical projection system 10 when luminescence unit 12 is lighted failure.By this, when optical projection system 10 was restarted, C were to cooling unit 14 for control module 16 output cooling earlier control signal, and in advance optical projection system 10 being cooled off, and then output drive signal D lights luminescence unit 12.Control method that it should be noted that the embodiment of the control method of this embodiment and Fig. 1 can't be mutually exclusive, and can be suitable for simultaneously.
Please refer to shown in Figure 5ly, be the synoptic diagram of cooling unit one preferred embodiment of the present invention, as shown in FIG., this cooling unit 14 has a fan 142 and a fan drive circuit 144.Wherein, fan drive circuit 144 is in order to the cooling control signal C of reception from control module 16, and then drive fan 142 runnings.
As previously mentioned, whether control module 16 is successfully lighted to detect luminescence unit 12 by receiving the response signal R of selfluminous cell 12.In order to carry out this testing process, as shown in Figure 6, this control module 16 can have an optical sensor 162.Utilize this optical sensor 162 to detect luminescence unit 12 whether luminous (luminescence unit 12 not luminous, can be considered a kind of response signal that expression luminescence unit 12 is not successfully lighted), to judge whether luminescence unit 12 is successfully lighted.
In addition, as shown in Figure 7, this control module 16 can also use a typical voltage or a current detector 164, the pressure reduction of two electrodes by detecting luminescence unit 12 changes (when luminescence unit 12 is lighted, the pressure reduction of two electrodes can descend), or detect whether current flowing is arranged between two electrodes (when luminescence unit 12 is lighted, current flowing being arranged promptly between two electrodes), whether successfully lighted to detect luminescence unit 12.
Though the present invention with preferred embodiment openly as above; right its is not that any those skilled in the art are under the situation that does not break away from the spirit and scope of the present invention in order to qualification the present invention; can change and modification, so protection scope of the present invention is as the criterion with the claim institute restricted portion that is proposed.